# Grizzly G0678 8x30: Repair, Scraping and Alignment



## AndySomogyi

Bought this Grizzly mill used about a year ago, big mistake, buying used.

I’m not a machinist, and didn’t realize the idiot I bought it from removed the way wipers to install a DRO. Ha ha, guess that makes me an idiot also for not checkin.

Huge mistake buying used, not doing that again.

Of course the ways were all gouged up, and took it apart, just planning on stoneing it, and cleaning it out.

But from the factory, OMFG what a disaster! The ways literally look like they were cut with an AXE!

Factory ways were massively gouged, and  iout of flat by about 0.015”! Yeah, the big dips here are almost fifteen thousands deep.

After some scraping, with angle die grinder, got it from 0.015 dips down to basically flat and 0.001 taper. 

Still needs some work but getting there 

Before ways looked like they were literally cut with an axe, so big improvement

The mill doesn’t need to be perfect, just needs to work well enough to make some parts.

I have some other most posts on this, but figured I’d put them together in one thread Incase anyone wants info on these machines.


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## AndySomogyi

Argh!!!!

Freaking Grizzly!

I got the saddle scraped essentially flat, I go to test it on the knee and it ROCKS back and forth.

Triple check the saddle on the surface plate and it’s dead on.

So I measure the knee ways, put a test indicator on the spindle. The right side way is dead on, out of square by 0.0005 over 10”.

But the left side is FREAKING SIX THOUSANDS HIGH in the front. No wonder the saddle rocks and this is why I couldn’t Machine a square part.

So I guess I need to scrape 6 thousands off the front corner


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## AndySomogyi

My renegade level, Starrett 099 with a 199 vial confirms the ways are twisted badly.

Interesting thing is the that top surface is parallel with the flats, so it was ground all screwed up.


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## AndySomogyi

Ha ha, sweet, I can use the saddle upside down and rotated 90° as a straight edge to verify the knee .

The top of the saddle is pretty decent, basically needs about an hour or so of scraping to get it nice, but it’s flat now, just needs a touch up.


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## AndySomogyi

Started with about 6 thousands twist in the knee ways. It was ground that way from the factory, IDK, maybe clamped it weird? 

Anyways, that explains why I couldn’t make a square part. 

After a few hours hand scraping, twist is zero, and continuing flattening them. Made sure they are square with the spindle. 

I don’t have a straightedge, but I found flipping the saddle upside down makes a perfect standard to scrape to. Yes, I trued the top is the saddle up on the surface plate first.


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## markba633csi

Now you've done it- you've made it so good you won't want to sell it.    
-Mark


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## Larry$

Any idea how old the machine is?
Was it used as a production machine?
I've had both good and bad luck buying used. Some of my best production equipment was bought used.


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## mattthemuppet2

I'll be following along. I have a smaller version of this mill (6x26) and I need to take the knee off to clear out an oil passage. No other obvious issues but you never know what you might find!


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## AndySomogyi

Larry$ said:


> Any idea how old the machine is?
> Was it used as a production machine?
> I've had both good and bad luck buying used. Some of my best production equipment was bought used.



Looked it up, and I think it was made in 2010, and was used by a home gunsmith guy, was never used in production. 

There's no real true wear on it, all the issues with it are a combination of horrendously bad work at the factory, like with the saddle ways cut with an axe, and knee ways ground with a 0.006 twist., and stupid things by the previous owner like removing the way wipers to install a DRO. 

So, a combination of no way wipers, bad and twisted ways allowed chips to get lodged between the ways, and this just destroyed them.


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## AndySomogyi

mattthemuppet2 said:


> I'll be following along. I have a smaller version of this mill (6x26) and I need to take the knee off to clear out an oil passage. No other obvious issues but you never know what you might find!



Jim has a write up on your exact machine here:






						Benchtest.Com - Workshop - Rebuilding the Grizzly G3103 Part 2
					






					www.benchtest.com
				




I think if yours is anything like mine, you’ll me appalled at the “quality” of factory work.

Some tricks I’ve found are:

Have to make sure knee ways are perpendicular to spindle. In theory they should be perpendicular to column also, but since these machines don’t have a nod adjust on the head, the spindle is most important.

I don’t have a large precision square, so what I did was use a test indicate in the spindle and measure 4 points on the ways. This confirmed why the freshly scraped saddle was rocking.

I also don’t have a big straight edge, but turns out that the saddle flipped upside down and rotated 90° works perfectly and is even better because it lets to do both the ways as the same time and makes sure that both ways are in the same plane. 

Other thing is if you measure / work the knee, MAKE SURE it’s loaded, I.e.  z screw has compression and is holding. The knee will rock about 2 thousands / 12” when you go from loaded to unloaded. 

I was working until about 4 AM last night on this, just inking the saddle and scraping the ways. I just tested it this morning and wow, got them both parallel and square to the spindle to within 0.0005 over 12”.


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## mattthemuppet2

to be honest so far I've been pretty impressed - the nod was out by a touch, so I sorted that out with a piece of 7-up can between the knuckle and the base, which put it within 0.01mm over the width of the table. All the sliding surfaces are in good condition, no gouges or ugly machining marks, just the usual Chinese way cutter marks on the flats. Backlash is minimal and there's little (0.01mm or so) movement in any of the axes between locked and unlocked. The gibs are different on mine though - they're adjustable from the ends, not the sides, if that makes any difference. I guess it's just the luck of the draw.


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## AndySomogyi

Someone just shoot me in the freaking head 

Got the knee nice and flat against the saddle and square in the y direction against the column, and I assumed the ground flat on the top of the knee was a reference.

The freaking knee is tilted against the column in the X direction BY FREAKING 15 THOUSANDS OVER 8 INCHES !!!!!

My choices are 

(1) pull the knee off somehow and scrape the knee dovetail 

(2) hack 15 thousands off the right knee to saddle way 

(3) simplest is make the saddle not parallel and hack 0.015 off the right saddle way to compensate for the misaligned knee. 

Damn these CRAP machines!!!!


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## Larry$

mattthemuppet2 said:


> to be honest so far I've been pretty impressed - the nod was out by a touch, so I sorted that out with a piece of 7-up can between the knuckle and the base, which put it within 0.01mm over the width of the table. All the sliding surfaces are in good condition, no gouges or ugly machining marks, just the usual Chinese way cutter marks on the flats. Backlash is minimal and there's little (0.01mm or so) movement in any of the axes between locked and unlocked. The gibs are different on mine though - they're adjustable from the ends, not the sides, if that makes any difference. I guess it's just the luck of the draw.


The gibs that adjust from the ends are tapered and I think can be a better solution. Assuming well done.


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## AndySomogyi

Larry$ said:


> The gibs that adjust from the ends are tapered and I think can be a better solution. Assuming well done.



Not sure I follow you. The knee is currently cocked at an angle about the y axis relative to the column. On the knee to column dovetails, the right side is fixed and left side had a tapered gib that provides a tension, but it’s the fixed dovetail on the right that mostly sets the angle.


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## mattthemuppet2

I don't think that he's talking about your alignment issue, more that tapered gibs can be better than straight gibs.

For your knee, from what little I know/ have read about scraping in knee mills I thought that the column dovetail had to be scraped in first, then the knee to column dovetail, then the knee to saddle dovetail (square to column in both horizontal and vertical planes). Otherwise there's the risk of chasing your tail. That's all just book and forum learning though, you'd be well off to seek some advice from the pros.


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## AndySomogyi

mattthemuppet2 said:


> I don't think that he's talking about your alignment issue, more that tapered gibs can be better than straight gibs.
> 
> For your knee, from what little I know/ have read about scraping in knee mills I thought that the column dovetail had to be scraped in first, then the knee to column dovetail, then the knee to saddle dovetail (square to column in both horizontal and vertical planes). Otherwise there's the risk of chasing your tail. That's all just book and forum learning though, you'd be well off to seek some advice from the pros.



I really want to do as little as possible to this mill, all I care is that I can make a square part.

My original plan was to just pull the saddle off and clean up the ways, put it back together. I had no idea I’d find such massive alignment issues.

So what I’m going to do now is pull the knee off and get that scraped square with itself. I just ordered one of these frame squares off eBay, and use that to scrape the knee in.

I’ve got the saddle pretty close to being parallel with itself. 

But I’m totally going to leave the column dovetails alone, they look decent and I’m not going to bother with it. 


Sent from my iPhone using Tapatalk Pro


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## mattthemuppet2

that's a lot of work for sure!


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## AndySomogyi

Knee’s out, its a lot lighter than I thought it would be, it’s only about 75 lbs, I could have lifted it out by hand easy. But I did make a little plate to hold it and lifted it with engine hoist.

Well, apart from the gib being stuck. 

The lead screw to bearing fit wasn’t exactly a slip fit, so had to hold the knee and back the screw downward by hand to pull it from the bearing. 

After you pull the knee up most of the way, you can pull the gib out and tilt the knee forward and it clears the head just fine.


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## AndySomogyi

Not a good sign then the factory bondos over screws. Not cool Grizzly, not cool.


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## AndySomogyi

Here’s what I mean about the knee dovetails.


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## AndySomogyi

Made a variation of Nick Mueller’s dovetail alignment jig, all with hand tools (because my mill is broken and need this to fix it).

Confirmed my previous measurements of the knee on the mill. 

This is a weird mill, because the surface ground parts are really pretty nice, but looks like the knee shifted when they were grinding the top ways, and the dovetails look like they were cut with an axe.

Now confirming how bad the dovetails are, I guess it’s a good thing I pulled the knee. 

Got some work to do, but at least can confirm how much I need to cut off the dovetails.


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## AndySomogyi

Bought a no-name box level off eBay (hey, it’s what I can afford) 

Inspected it and it’s dead nuts parallel, but way off in squareness, basically it’s a parallelogram.

Argh!@$!@& can’t anything go right with these POS tools I have ?!?!

Anyways, my options are (a) send it back and hope they send me another one that’s in-spec, or (b) try to get a partial refund, and scrape it square.

I’m sick of wasting time on this stupid mill, I just want to get back to making parts. 

Note, by rules of geometry, squares are self-proving with a test indicator.

This one is about 0.006” out of square.


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## Richard King 2

Andy,  If you setting the dovetail device on top on the clearance surface is the clearance surface co-planar to the scraped flats?  If I were checking it I would set the device on the flats with the dowel pin pressed against the dove tail and reaching over the clearance surfaces and indicating the opposite dovetail.


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## AndySomogyi

Richard King 2 said:


> Andy,  If you setting the dovetail device on top on the clearance surface is the clearance surface co-planar to the scraped flats?  If I were checking it I would set the device on the flats with the dowel pin pressed against the dove tail and reaching over the clearance surfaces and indicating the opposite dovetail.



Thanks for the info. As you point out, what matters is the alignment between the dovetails and the bearing flats, the top clearance surface doesn’t make contact with anything.

On the top flats, it’s easy because you just put a dowel pin between the dovetail and flats. On the back flats or column flats (sorry, I forget the correct term), you again need to measure dovetails relative to flats. That’s why I made the alignment jig, to position the dowel pin a fixed length relative to the bearing flats.

So I was using the jig on the back flats, indicating against a try square on a surface plate. I made sure the knee top flats and surface plate were co-planar and level. I built my workbench with an adjustable cast iron surf plate, and the entire thing is welded 2” box tube. 

I also plan to flip it upside down, and set the top flats on 123 blocks on my granite surface plate and re-measure. 

Then I plan to align the top dovetails by resting the knee on the back flats on the surface plate and measuring the top dovetails.

Just want to check, I’m making all these measurements with the knee on the bench, in a static, unloaded configuration. Basically making sure the knee itself is square and true by itself. Is that the right approach? 

The back flats, you said they should be scraped so the front of the knee tips up about 0.0005, so I’ll try to shoot for that figure.


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## Richard King 2

You say it is taking so long.  " reason in my opinion" You are re-inventing the wheel.  Making things so complicated.  I can scrape a bridgeport that is in terrible shape in 40 hours.  Column, back of knee, top of knee, bottom of saddle, match fit all the gibs.  I get the table ground and then match fit that to the saddle.   I have re-scraped over 50 Bridgeport's and have been trying to advise you on "how to do it"  I  have taught thousands of people to not only rebuild machines, but have taught Bridgeport employee's, dozens of new machine building companies around the world.   You have scraped 1 or 2 machines?   Nick Muller is also self taught and also does not scrape as a professional, he is and electronics engineer.    I am here to help and I recommended Hobby Machinist to you when you started to write on another forum.   You came looking for help I thought, not show how your doing it with little to no experience, guessing as you go, reading the Connelly book helps, but it also was organized by Connelly, he was not a machine builder or rebuilder.  Look at the front of the book where he acknowledges other people who wrote chapters in the book.  I Never check the back of the knee like your showing.  You need to scrape and check it on the column.  I have to go teach another class today and I can write some more tonight.   I hope this does not hurt your feelings, but how many hours do you have in the rebuild?  100 +?   I hate to say it, but I am sure even the way it was off a mike, I could have the machine scraped in 30 hours.  It's a mini Bridgeport.


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## AndySomogyi

Richard King 2 said:


> You say it is taking so long.  " reason in my opinion" You are re-inventing the wheel.  Making things so complicated.  I can scrape a bridgeport that is in terrible shape in 40 hours.  Column, back of knee, top of knee, bottom of saddle, match fit all the gibs.  I get the table ground and then match fit that to the saddle.   I have re-scraped over 50 Bridgeport's and have been trying to advise you on "how to do it"  I  have taught thousands of people to not only rebuild machines, but have taught Bridgeport employee's, dozens of new machine building companies around the world.   You have scraped 1 or 2 machines?   Nick Muller is also self taught and also does not scrape as a professional, he is and electronics engineer.    I am here to help and I recommended Hobby Machinist to you when you started to write on another forum.   You came looking for help I thought, not show how your doing it with little to no experience, guessing as you go, reading the Connelly book helps, but it also was organized by Connelly, he was not a machine builder or rebuilder.  Look at the front of the book where he acknowledges other people who wrote chapters in the book.  I Never check the back of the knee like your showing.  You need to scrape and check it on the column.  I have to go teach another class today and I can write some more tonight.   I hope this does not hurt your feelings, but how many hours do you have in the rebuild?  100 +?   I hate to say it, but I am sure even the way it was off a mike, I could have the machine scraped in 30 hours.  It's a mini Bridgeport.



Thanks Richard, I do appreciate your insight.

I’ll move it over to the column and try to measure it there also.

I fully admit, I have no idea what I’m doing here. At my day job, I’m a staff scientist, not a machinist. As such, I don’t have the experience in rebuilding to know what the right ‘feels’ or the generally accepted procedures, aside from the Connelly book. 

I also don’t have all the fancy tools rebuilders have, and my salary is crap so I can’t afford top shelf tools. Got to make do.

One thing I do know from science is you need multiple different experiments to confirm something, you can’t trust just one. That’s why I’m using different measurement approaches to measure the same thing, so that they confirm each other. Because I know I don’t have any experience here, I’m trying to be careful with my measures, as I can’t be sure I’m doing it right. 

I have no idea how many hours I have in this, have a day job so only spend maybe 2-3 hours an day, so maybe 50 hours? And a lot of that was making things like a brazed scraper and jig.


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## AndySomogyi

I’m a total noob at scraping these kind of instruments (I’ve scraped babbitt bearings in engines and lathe saddle, about it), but I’ve got the sides flat and parallel to under a tenth and squareness to couple tenths. Using the method from Moore’s “Foundations of Mechanical Accuracy” pages 33 and 34 (attached).

Started with this cheap ass square almost 0.010 out of square. First got it close with a belt sander then switched to the hand scrapers (made both of them).

Going to tweak the squareness a bit more, see how good I can get it.

BTW, eBay seller is allegedly going to get me a refund.


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## Richard King 2

I purchased the Moore Book 40 or so years ago, the Connelly book 50 years ago. I always teach "Never assume anything, prove it"   I understand your a scientist and need to prove things to.  What I am afraid of and why I wrote what I wrote is because some rookie who has never scraped a machine reads your info and does it your way.  I have offered you help and you read but still do it your way.  You quote books, show you tube or quote them and not listen to me.   Your making something so simple so complicated.   Good Luck


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## Rex Walters

Hi, Richard. I suspect that, like me, Andy didn't "do it his way" because he disagreed with you or intentionally ignored what you wrote. I think he simply didn't understand (or misunderstood) what you were trying to say.



Richard King 2 said:


> If you setting the dovetail device on top on the clearance surface is the clearance surface co-planar to the scraped flats? If I were checking it I would set the device on the flats with the dowel pin pressed against the dove tail and reaching over the clearance surfaces and indicating the opposite dovetail.



There's a lot to unpack there. It took me several reads to understand what you meant. Like almost everything I've learned from you about scraping and rebuilding, it's hard to understand in written words. It'd be simple enough to understand in person with our hands on a real machine and real tools, but it's hard to visualize in words. Sadly, it's not always feasible for you to provide photos or videos for every point, much less show things in person (which is why your classes are so valuable). So we have to struggle and communicate with written words.

Please try not to get so frustrated when we don't understand. It *usually* takes more than one attempt to get something across in words.

Andy: Unrelated to the mill, but one point about checking squareness. This photo shows you laying the dowel pin on its side:




I believe the better technique is to place the pin *on end, *registering in a vee at the front of the indicator base. You then sweep the indicator, looking for max deflection with base, pin, and square all remaining in contact while rotating the base. You can also use a steel ball in a vee, or simply attach a semicircular bearing plate to the front of the base. In other words, *point* contact is better than *line* contact. I'd also draw a line parallel to one edge of the square with a sharpie and ensure the dowel pin and indicator tip are both touching the same line. The surface of the square is a plane that can be tipped on *two* different axes. You want to use your indicator as squareness comparator of a single *line *on that surface. Think: *points* to establish a *line* that sits on the *plane*. The pin-on-end registering in a vee gives you three-point contact at the base of the line you're verifying, and the indicator tip establishes the point at the other end of that line.

I'm sure you fully understand, but for completeness: The process I'd use to check a precision square is to first verify that two opposing faces are truly parallel (checking all four corners and the center of the top face with the indicator referencing from the same plate, as you've done). Then I'd draw a line a fixed distance from the edge of an orthogonal face (one of the faces you're testing for squareness). I'd then adjust the indicator so the dowel pin and indicator tip both touch the same line, sweep to find max deviation, and zero the indicator. Finally, I'd turn the square upside down, reference points on the same line, and sweep for max deviation. Any non-zero measurement indicates double the error.

I doubt you'll measure very different results if it's out several thou (which is shocking, tbh) but it does matter when you are checking something that's gage quality (tenths).


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## AndySomogyi

Rex Walters said:


> Hi, Richard. I suspect that, like me, Andy didn't "do it his way" because he disagreed with you or intentionally ignored what you wrote. I think he simply didn't understand (or misunderstood) what you were trying to say.
> 
> 
> 
> There's a lot to unpack there. It took me several reads to understand what you meant. Like almost everything I've learned from you about scraping and rebuilding, it's hard to understand in written words. It'd be simple enough to understand in person with our hands on a real machine and real tools, but it's hard to visualize in words. Sadly, it's not always feasible for you to provide photos or videos for every point, much less show things in person (which is why your classes are so valuable). So we have to struggle and communicate with written words.
> 
> Please try not to get so frustrated when we don't understand. It *usually* takes more than one attempt to get something across in words.
> 
> Andy: Unrelated to the mill, but one point about checking squareness. This photo shows you laying the dowel pin on its side:
> 
> View attachment 341258
> 
> 
> I believe the better technique is to place the pin *on end, *registering in a vee at the front of the indicator base. You then sweep the indicator, looking for max deflection with base, pin, and square all remaining in contact while rotating the base. You can also use a steel ball in a vee, or simply attach a semicircular bearing plate to the front of the base. In other words, *point* contact is better than *line* contact. I'd also draw a line parallel to one edge of the square with a sharpie and ensure the dowel pin and indicator tip are both touching the same line. The surface of the square is a plane that can be tipped on *two* different axes. You want to use your indicator as squareness comparator of a single *line *on that surface. Think: *points* to establish a *line* that sits on the *plane*. The pin-on-end registering in a vee gives you three-point contact at the base of the line you're verifying, and the indicator tip establishes the point at the other end of that line.
> 
> I'm sure you fully understand, but for completeness: The process I'd use to check a precision square is to first verify that two opposing faces are truly parallel (checking all four corners and the center of the top face with the indicator referencing from the same plate, as you've done). Then I'd draw a line a fixed distance from the edge of an orthogonal face (one of the faces you're testing for squareness). I'd then adjust the indicator so the dowel pin and indicator tip both touch the same line, sweep to find max deviation, and zero the indicator. Finally, I'd turn the square upside down, reference points on the same line, and sweep for max deviation. Any non-zero measurement indicates double the error.
> 
> I doubt you'll measure very different results if it's out several thou (which is shocking, tbh) but it does matter when you are checking something that's gage quality (tenths).




Thanks Rex

I think my pic was a bit misleading. Basically what I did was lay the dowel flat, but sweep using the ball end of the indicator, and look for maximum height. First scraped one opposite pair of sides parallel, then scraped the remaining sides perpendicular to them.

I like your idea of a bearing as a measuring probe, I’ll try that also.

I used the ball end as a sort of squareness comparator. The reason I used the dowel is this is a scraped surface, so the ball end of the surface gauge would bounce around too much (using an tenths indicator), used the dowel to get a line contact of the bearing surface.

And on the top, I used a lapped carbide insert to get a measure of the top bearing surface (tenths indicator bounces too much).

I just called up the instruments guys at work and they said I can come in and use the clean room instruments to measure it, so we’ll see how good my work is. My tenths indicator shows about 2 tenths when inverting the part, which is 1 tenth out of square. And yes, tested all 4 faces. Ha ha, when I started, the sides were all bowed by about 0.0005, and out of square by about 0.010, yes, about then thousands out of square. It was so bad, I did the rough work with a belt sander .

Note: interesting thing is now this scraped square is more flat than my surface plate, as I can test different spots on my surface plate, and hinging the square feels slightly different in different spots. Basically using the square as a sphereometer.


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## Richard King 2

Yes I thought of you while I was writing that,


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## Rex Walters

AndySomogyi said:


> Basically what I did was lay the dowel flat, but sweep using the ball end of the indicator [against the dowel], and look for maximum height.



Ah. I see. 

Yes, for a scraped surface you want something to average out the scraped points. I think a gage block or parallel might work better, though, and is more commonly used for the purpose. I'd rather have the ball against a plane than against a cylinder. Any vertical discrepancy will translate to a horizontal discrepancy with the latter. The carbide blade you used at top is probably flat and parallel (but I'd still check it!).

I've tried using the ball at the end of the indicator stand rod to test squareness, but without much success. Rich told me that's indeed it's intended purpose, but it's so small that it's tricky to get an accurate reading. I slotted the front of my indicator base to hold a small plate with a curved front and use that for the purpose (the curve doesn't even need to be terribly accurate — belt sanding or filing a fair curve suffices). That or a large steel ball held in a vee works better for me.

I think you should get your plate re-ground and calibrated if you don't trust it, though. You're almost certainly fooling yourself if you think you've made something more accurate than the plate by scraping it in relative to the plate! If the part hinges well on one part of the plate but differently on another (and you've ensured everything is spotlessly clean) then there is no way to know which area is truly flat (probably neither).


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## AndySomogyi

Rex Walters said:


> Ah. I see.
> 
> Yes, for a scraped surface you want something to average out the scraped points. I think a gage block or parallel might work better, though, and is more commonly used for the purpose. I'd rather have the ball against a plane than against a cylinder. Any vertical discrepancy will translate to a horizontal discrepancy with the latter. The carbide blade you used at top is probably flat and parallel (but I'd still check it!).
> 
> I've tried using the ball at the end of the indicator stand rod to test squareness, but without much success. Rich told me that's indeed it's intended purpose, but it's so small that it's tricky to get an accurate reading. I slotted the front of my indicator base to hold a small plate with a curved front and use that for the purpose (the curve doesn't even need to be terribly accurate — belt sanding or filing a fair curve suffices). That or a large steel ball held in a vee works better for me.
> 
> I think you should get your plate re-ground and calibrated if you don't trust it, though. You're almost certainly fooling yourself if you think you've made something more accurate than the plate by scraping it in relative to the plate! If the part hinges well on one part of the plate but differently on another (and you've ensured everything is spotlessly clean) then there is no way to know which area is truly flat (probably neither).



It is a little tricky using the ball end and lining up the indicator so the apex of the ark is close to perpendicular, def takes some time to line them up right.

I did measure the carbide, it’s dead nuts flat. I considered my gauge blocks, but didn’t want to chance scratching up the faces. I used both a dowel and parallel. We’ll see what the metrology lab at work has, the guy that runs it wants to take a look at this square.

I did some basic tests of flatness of my surf plate, used my Starett 199 on a 6” between centers and didn’t record any true dips, and sweeping with my tenths indicator didn’t show any clear patterns of dips. There does seem to be a slight dip in the front middle, from doing the spherometer test, but it seems to be too low to register on a tenths indicator.

My surf plate is a 18x24 black Starrett, and I  do wonder what it might cost to get the surf plate lapped. In my experience, at least here in Indiana, shops only want to deal with commercial customers, and quote egregious prices to individuals. Like I tried to get some parts ground, and places I talked to wanted me to set up a commercial account, pay for all sorts of consulting fees and had something like $5,000 minimum order. Might be cheaper to buy a new one from Shars.

Anyways, I don't find it surprising that you can scrape something that's more accurate than the surface plate used as a master if the sampling distribution is uniform. The *law of large numbers*, in probability and statistics, states that as a sample size grows, its mean gets closer to the average of the whole population. So, when I'm working on improving the pattern, I make sure to sample from different areas of the surface plate, and avoid inking in the same direction / pattern. This way, I sample a larger distribution of the surface plate, and get closer to the mean flatness. Also, when I get to finish scraping, I don't scrape every high spot, instead, I do a random sampling, and only look to improve the statistical distribution of spots.  Basically similar idea to when you're painting a car, and doing many light dusting coats. 

One of the projects I do want to make is an autocolimator, might make one and lap my plate when I get all this other junk finished. I really do need to get back to making car parts, so I need to get my stupid mill fixed.


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## AndySomogyi

Got some more work done on this. Got both sides of the saddle scraped in, and both sides are parallel to about 2 tenths over 10”.

I know the bottom of the saddle isn’t perfect, there’s a 1/2” spot towards the outside where the ink density is pretty low, but I’m not too bothered about it. 

Not sure, but I’m thinking this ink pattern is good enough for mill ways.

In any case, it’s multiple orders of magnitude better than what it was before. Before, both the top and bottom looked like they were cut with an axe, and had like almost 20 thousands dips and way way out of parallel.
Now going to use the saddle as a master to ink the knee. 

The weird thing is that this is actually a really nice casting. The iron is very even, no casting voids or bubbles at all, very nice uniform grain structure and scrapes very nicely. It’s definitely a better quality casting than my 1950’s Clausing. It’s just the factory finishing thats horrible.


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## AndySomogyi

Got the box square scraped in. Been swamped with day job stuff so haven't had a chance to work on this. 

Took the square in to our instrumentation lab at work, and measured it in the clean room, it's flat and parallel to 50 millionths, and square to just under a tenth.

I'd say that's decent for a first time at this.


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## AndySomogyi

Getting back to this project, been swamped at work for a while.

Finally got around to scraping in the ghetto straightedge I made from an old sewer grate, now using it the scrape in and align the knee ways.

Knee ways originally started out with about 15 thousands of twist, now down to a few tenths, still doing a rough scrape on the knee.

Note, the twist wasn’t from wear, that’s how the surface was ground at the factory. I’m guessing the casting must have slipped during the grind operation, or maybe they they had to re-position to grind the left and right ways and didn’t align it properly, don’t know. All I know is it was pretty sorry shape when I started and that clearly explains why I could not mill a square surface. 

To ensure the knee top flats are co-planar, I first scraped the saddle in on the surf plate, and I alternate between printing with the saddle and with the straight edge. You need the straightedge to ensure the length of the ways is flat, and the saddle to ensure both flats are co-planar. I also regularly check for twist to make sure nothing is getting wonky. 

With the straightedge, when I get around to it, I might scrape a few more PPI in the straight edge, but figure this is good enough for now.


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## mattthemuppet2

fantastic work, that'll be a cracking mill by the time you're done. Any plans on doing the head/ knuckle junction? I remember reading about someone else scraping in a small knee mill like this and that was another area that benefited from some work. How long did it take you to machine your straight edge to rough shape? Looks like a decent sized lump of CI!


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## AndySomogyi

mattthemuppet2 said:


> fantastic work, that'll be a cracking mill by the time you're done. Any plans on doing the head/ knuckle junction? I remember reading about someone else scraping in a small knee mill like this and that was another area that benefited from some work. How long did it take you to machine your straight edge to rough shape? Looks like a decent sized lump of CI!


Thanks man, it's getting there, very slowly though. Have a day job and don't have a lot of time to work on this. 

For the time being, I'm just going to leave the head / knuckle junction alone, I just want to get the mill back together, got a lot of projects I need to get done with it. But I'll definitely re-visit the head/knuckle when I get some time. 

I'm planning on making a vertical shaper attachment that would bolt up where the motor currently sits, and re-locate the motor flipped 180 degrees vertically, closer to the head. 

That straight edge, I think it took maybe an couple hours with a sawz-all first, then probably 3-4 hours of milling time. This isn't the most rigid mill, so it was limited to about 0.030 depth of cuts with a face mill.


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## Larry$

How does one know when a piece of metal is fully "relaxed" and not subject to movement as time goes by? If there are stresses in the metal and part of it is removed then the stresses will cause the metal to change shape. I've seen this in cast iron.


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## AndySomogyi

Larry$ said:


> How does one know when a piece of metal is fully "relaxed" and not subject to movement as time goes by? If there are stresses in the metal and part of it is removed then the stresses will cause the metal to change shape. I've seen this in cast iron.


If you want to get fancy about it, you send it out to get thermally stress relieved. In a home shop, you can shot peen it , or hand peen it with a hammer. That would cause many stressed lattice dislocations that are susceptible to move to move. Or you can leave it outside for a while. 

Basically the idea is you want to encourage any movement that will happen, to happen before the final finishing operations.


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## Larry$

Andy, Yes there are multiple ways of "stress relieving" but how do you know when it is fully relaxed. Traditionally casting were thrown out back to "rest." Some are now put through a high frequency shaking. FULLY??? If you are measuring to tenths , FULLY would seem to be a requirement.


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## AndySomogyi

Larry$ said:


> Andy, Yes there are multiple ways of "stress relieving" but how do you know when it is fully relaxed. Traditionally casting were thrown out back to "rest." Some are now put through a high frequency shaking. FULLY??? If you are measuring to tenths , FULLY would seem to be a requirement.


Published empirical measurements show that thermal stress relief eliminates virtually all stresses with about a 5 hour bake, I don’t have the reports in front of me, so don’t quote me on the exact number. Conventional and mechanical aging do the same.

The castings on this mill are about 20 years old, and have been through countless vibration cycles.

Judging by the amount of rust I took off, I’d estimate the straight edge to be about 50 years old. Furthermore, I mechanically stress relieved it, and let it sit outside for about a year after I machined it.

I’d have to look up the papers that report on these methods and the exact published numbers, but I tried to follow published mechanical stress relieving procedures. 

So I’m reasonably confident these are stable. Furthermore, I use many different measures for the same thing, i.e. three separate metrics to ensure ways are co-planar. Geometrically, the possible way the metrics all agree are if the planes are co-planar.


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## Larry$

Sounds like you have it under control. A lot of work. You must enjoy a challenge.


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## AndySomogyi

Larry$ said:


> Sounds like you have it under control. A lot of work. You must enjoy a challenge.


I'm getting there. 

A challenge, I don't know... When I bought this mill, I didn't realize how bad these were, and I figure, once you buy something, you're stuck with it. So, just trying to make the best of what I've got to work with.


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## AndySomogyi

Got a few hours of work in on thisUsing my version of Nick Müler’s dovetail alignment tool to line up the squareness of the knee. 



It’s important that the square is aligned with the top flats so side motion of the block doesn’t throw off reading.

Here’s first print of the column,  LOL, THREE points of contact. Not 3PPI, but three points of contact total.


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## AndySomogyi

Roughing in the back ways, they’re a freaking disaster from the factory. Started out with about 20-25 thousands of wallow.

Still can’t understand how could the factory  have produced something this bad. Like I said, the machine ground surfaces aren’t bad, it the hand finished ones that are a disaster.

Tried an angle grinder and wasn’t having much luck, but your mileage will vary. If I tried to just dust the high spots, grinder wasn’t really moving more material than heavy scraper push. And I was afraid to push the grinder for fear of digging in. I’m going to try a big file as some have suggested. But down to about 10 thousands now, its contacting evenly, just still have that big dip by the oil grove that I want to get rid of.


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## AndySomogyi

After 20-25 some odd thousands, finally getting viable prints. Checking the squareness on the surface plate relative to the top flats every other print

At least getting a good workout lifting this 100 lbs knee around


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## AndySomogyi

using the box square as a master to scrape the knee square. I’m both inking the square, and indicating against it with a DTI, both confirm that I still need to twist the knee up a few tenths.

Yes, I realize that the usual method is to complete disassemble the mill, rotate the column horizontal and use that as a master, however I simply don’t have a way to move the column solo . One man shop with no forklifts, or anything, only my own muscle, and whilst I’m strong, I simply can’t move a column on my own.


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## AndySomogyi

Back flats are square to the top flats within 0.0002 / 10” with the front end tilting up by that amount.

Thinking this is good enough for a Grizzly ha ha, so calling it a day.


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## AndySomogyi

Put the knee back on the column and checking alignment. Reassuringly, the alignment about the X axis was dead, within 0.0003 over 8", which is what the surface plate showed. But twist about the Y axis is a disaster, this is what started me down this rabbit hole.

So, next steps is scraping the dovetails.


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## AndySomogyi

Made some progress rough scraping in the dovetails. Started with between 15-20 thousands of twist over 8", down to about 0.002.

Technique I used was the dovetail alignment jig, sliding on the column dovetails. Did this because I don't have a way to rotate the column horizontally, have to do it in the vertical direction, and needed to tap the gib in to make sure the guild dovetail is firmly seated against the column dovetail.

The gib also obviously needed A LOT material removing, roughed it in with the belt sander.

Yes, I fully realize there is some possible cosine error indicating on the column, that's why I'm only using this to rough it in. I needed to know how much space I'll need to fill, to order the right shim stock to build up the gib. When I get the gib fitted, I'll ink up the column, fix the indicator to the column, and use the vertical screw to move the knee up and down to get a reading to do the final scraping.

The knee is now very very perpendicular to the column, measured in 5 different spots, and it's a 2-3 tenths out of perpendicular.

Verified the parallelism of the top flats that I scraped, and they are dead flat and co-planar to within about a tenth.


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## AndySomogyi

Started scraping in the knee dovetails.

when I started, they were out of parallel by 0.004, now down to a few tenths.

next step is scrape the pocket for the gib and guide way on the saddle to match the knee dovetails, at least that’s what I think Connelly said, and makes sense.


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## AndySomogyi

Finishing up scraping the knee dovetails. These were a real pain because it’s really awkward to balance my straight edge on it. My strait edge is a 45° and dovetails are 60°.

I’m pretty sure I didn’t get the angles on the left and right exactly the same, hope that doesn’t ruin it. 

These numbers here are in ten thousands. Still not entirely happy with the pattern, for a few more passes to go, but getting there.


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## AndySomogyi

Roughing in the guiding way here on the bottom side of the saddle, ensuring it’s square to the top table ways. I’ve tested this square and it’s close, about 0.0004 out of square, I’ll switch to my precision box level for the final scrape. But got about 0.020 to scrape before that ha ha.

The guide way on both sides of the table were a disaster to start with. They were made with an angle grinder and have about 0.020 deep wallows in them.

I verified that the ground surface on the front and back of the saddle are pretty flat, and I scraped the guide way parallel to this surface.

I already scraped the dovetails on the knee straight and parallel to about 0.0001, and the guide way on the table is parallel to the face by about 0.0002.

This is finally the last guide way to scrape.


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## AndySomogyi

The gib locking screws on these low-end mills are a really poor design, just to cut costs. Main problem is only the corner of the screw touched the back of the gib and that wedged it in, and also applied a torque that pulled the gib in a direction.

So I did a slight improvement where I milled slots on the back of the gib using my friends drill press and dog-pointed the screws so the screw pushes straight in on the gib. I had to do this because I faced the back of the gibs with brass to have enough thickness. 

Yeah, it’s not as good as a Bridgeport design, but it’s what I could accomplish with a drill press.

Was sketchy AF making the slots with a drill press (because of course I don’t have access to another mill or any other machine tools). So went over to my friend’s house and used his drill press with a 1/8” end mill to cut these slots.

Made a little jig to secure the gibs as good as possible in the vise.

Then basically lightly clamped the table on the column and rotated it around by hand. Did this all with a whole bunch of plunge cuts to ensure all the load was in the axial direction so the drill Chuck wouldn’t come out.

Massively inaccurate, but hey it worked. And it ain’t wrong if it works.


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## rabler

Andy,
I think it is a credit to you for coming up with ways to make things work with what you have.  You've done some impressive work figuring out how to rebuilding that mill.


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## AndySomogyi

rabler said:


> Andy,
> I think it is a credit to you for coming up with ways to make things work with what you have.  You've done some impressive work figuring out how to rebuilding that mill.


Thanks man!

It’s definitely a challenge when you have to make do with what you have, and don’t have access to fancy luxury tools.


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## AndySomogyi

Here’s the method I cam up with to align both of the ways on the saddle, to ensure they are square with each other — to ensure the saddle is perpendicular with itself.

One of the challenges here is that the back ground face of the saddle isn’t exactly flat, but I’m trying to use this as a reference surface. It’s concave with about a 0.001 dip in the middle, but luckily it’s uniformly convex, so I can just indicate off the outer edges.

First I scraped the table dovetail as close to parallel with this surface. Basically I placed the test indicator on the bench and used the mill table as a master, and indicated on the saddle.

I verified this by placing the saddle on the surface plate, and using the dovetail alignment tool to check distance to the surface plate. This was within about 3 tenths over 15”.

Now the real challenge was how to check squareness of the knee way.

I first tried to clamp a square to the back reference surface, but this proved wildly inaccurate.

I then realize I could place the saddle on the surface plate, and use my square to indicate perpendicular to the back reference surface.

So I made another straight edge, and clamped it to the top of the saddle. The I can indicate on this plane. The straight edge must by definition be parallel to the knee guiding way, and perpendicular to the reference surface, which is parallel to the table guide way.

I also use the dovetail alignment tool to verify this measurement.

Yeah metrology in the HOME SHOP.


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## AndySomogyi

After scraping in the saddle dovetails, and the tapered gibs (which were a massive pain), I’m verifying the final alignment here by clamping the precision square to the table and sliding and locking the X and Y axis respectively.

Its SQUARE!

Verified that it’s within 0.0002 over 8”. Repeated the measure by rotating the square four times to ensure the measurements are correct and properly averages all errors.


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## AndySomogyi

Argh!!! The stupidity of this mill never ceases to amaze me.

Starting to put it back together, and realize it only had 1/2 of a one-shot oiler. There is no pressure feed to the bottom ways.

So I’m going to have to re-engineer this somehow.


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## Radials

They did you oil passages just a little differently on your mill than mine. 


On mine the feed groove connects all the way across to the supply holes for the Y-axis lubrication grooves below. Not that this is probably much better. I have contemplated reworking the oil supply lines on mine when I get around to taking the mill apart again to correct problems I am now noticing after using the machine fore quite some time. I have just resorted to manually applying oil in addition to the one shot to make sure everything is lubricated.

Also, the oil supply line on my knee going to the gib side for some reason delivers oil to the back side of the gib only. No oil actually makes it to the sliding surface of the gib as there are no passage ways thru the gib itself. I'm not sure how this is typically correctly done and is something else I would check on your machine. 

Maybe while you're at it add a lubrication supply to the leadscrew nuts? I have contemplated reworking mine with a small manifold with a couple valves to direct all the oil flow and pressure to specific locations on the mill. 

My X-axis dro is mounted to the front of the table as you mentioned you were considering. Things start to get tight with the scale but its doable. 


The gib locks don't work in my finding with the scale and cover in place. It was impossible to reset the handle tab positions. I purchased resettable handle locks from MC and they work great. https://www.mcmaster.com/6848K36/




With your saddle off the machine it would also be much easier to drill and tap the mounting holes for your Y-axis scale. I milled the casting flat where I wanted these hole located as it was pretty rough.


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## AndySomogyi

Radials said:


> They did you oil passages just a little differently on your mill than mine.
> View attachment 370287
> 
> On mine the feed groove connects all the way across to the supply holes for the Y-axis lubrication grooves below. Not that this is probably much better. I have contemplated reworking the oil supply lines on mine when I get around to taking the mill apart again to correct problems I am now noticing after using the machine fore quite some time. I have just resorted to manually applying oil in addition to the one shot to make sure everything is lubricated.
> 
> Also, the oil supply line on my knee going to the gib side for some reason delivers oil to the back side of the gib only. No oil actually makes it to the sliding surface of the gib as there are no passage ways thru the gib itself. I'm not sure how this is typically correctly done and is something else I would check on your machine.
> 
> Maybe while you're at it add a lubrication supply to the leadscrew nuts? I have contemplated reworking mine with a small manifold with a couple valves to direct all the oil flow and pressure to specific locations on the mill.
> 
> My X-axis dro is mounted to the front of the table as you mentioned you were considering. Things start to get tight with the scale but its doable.
> View attachment 370291
> 
> The gib locks don't work in my finding with the scale and cover in place. It was impossible to reset the handle tab positions. I purchased resettable handle locks from MC and they work great. https://www.mcmaster.com/6848K36/
> 
> View attachment 370292
> 
> 
> With your saddle off the machine it would also be much easier to drill and tap the mounting holes for your Y-axis scale. I milled the casting flat where I wanted these hole located as it was pretty rough.
> View attachment 370296


Thanks for the info.

My gib side way is the exact same way, with the oil going onto the backside of the gib. I’m going to drill a hole though the gib, to make a path for the oil to get to the face of it.

I’m trying to find out what size these tubing is, looks like a 4mm. I think what I’ll do is


Radials said:


> They did you oil passages just a little differently on your mill than mine.
> View attachment 370287
> 
> On mine the feed groove connects all the way across to the supply holes for the Y-axis lubrication grooves below. Not that this is probably much better. I have contemplated reworking the oil supply lines on mine when I get around to taking the mill apart again to correct problems I am now noticing after using the machine fore quite some time. I have just resorted to manually applying oil in addition to the one shot to make sure everything is lubricated.
> 
> Also, the oil supply line on my knee going to the gib side for some reason delivers oil to the back side of the gib only. No oil actually makes it to the sliding surface of the gib as there are no passage ways thru the gib itself. I'm not sure how this is typically correctly done and is something else I would check on your machine.
> 
> Maybe while you're at it add a lubrication supply to the leadscrew nuts? I have contemplated reworking mine with a small manifold with a couple valves to direct all the oil flow and pressure to specific locations on the mill.
> 
> My X-axis dro is mounted to the front of the table as you mentioned you were considering. Things start to get tight with the scale but its doable.
> View attachment 370291
> 
> The gib locks don't work in my finding with the scale and cover in place. It was impossible to reset the handle tab positions. I purchased resettable handle locks from MC and they work great. https://www.mcmaster.com/6848K36/
> 
> View attachment 370292
> 
> 
> With your saddle off the machine it would also be much easier to drill and tap the mounting holes for your Y-axis scale. I milled the casting flat where I wanted these hole located as it was pretty rough.
> View attachment 370296



Thanks for the info. My gib side column way is the exact same way, with oil going on the back side. What I’ll do is drill a hole though the gib to get oil to the face.

On the saddle, I’m currently trying to figure out what size these tubing is. Looks like the tubing is 4mm and compression fitting are M8x1.0. But the threaded elbow into knee are 1/8NPT.





I think what I’ll do is try to drill some holes on the inside of the saddle that’ll interest with the oil galleries, and feed pressurized oil to them with another one-shot T junction like this:


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## Radials

AndySomogyi said:


> I’m trying to find out what size these tubing is, looks like a 4mm.


Looking back at my MC orders it is 4mm. This is what I went with and it worked just fine.









						McMaster-Carr
					

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.




					www.mcmaster.com


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## AndySomogyi

Radials said:


> Looking back at my MC orders it is 4mm. This is what I went with and it worked just fine.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> McMaster-Carr
> 
> 
> McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
> 
> 
> 
> 
> www.mcmaster.com


Thanks, 

I think I've got an idea to get oil to the bottom, without drilling any additional holes. Basically it involves extending the upper troughs to connect with the existing drainage reservoir.  Going to do a bit of science, and calculate capillary length of an oil column for a given surface tension. I'll make a post when I've got the math worked out explaining it.


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## AndySomogyi

Turns out these mills never had any way wipers on the column ways. Considering the original ways were cut with a freaking axe and had about 0.030 wallows on them, figure the designers must have thought it wouldn’t make any difference. 

So what I did was make a bracket here to bolt on the back of the knee, and attached it with some M6x1.0 cap screws. It was a real bear making sure the holes and tap are perpendicular when all you’ve got to work with is a hand drill.

So when I get the mill back together, I’m going to make a bridge bracket to bolt to this that will secure some way wipers for the column

I do have a good plan worked out for the one shot oiler, I’m going to make a video when I discuss the roles of surface tension and capillary length WRT holding a column of fluid, and how I’ve modified the saddle to deliver pressurized oil to both the top and bottom ways.


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## AndySomogyi

First coat of primer after bondo and sanding. I brushed this coat on because I wanted it thick to fill a few rough spots I didn’t bondo. Will sand down tomorrow, then spray a coat and final paint.


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## jwmay

AndySomogyi said:


> I’m not a machinist, and didn’t realize the idiot I bought it from removed the way wipers to install a DRO





AndySomogyi said:


> Turns out these mills never had any way wipers on the column ways.


Well I hope you called that guy and apologized for calling him an idiot. Haha!

While it's obvious this has been frustrating for you, it's been very interesting to me. Another person with a Grizzly mill that has never made a square part.  I assumed it was me. Maybe it's not?


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## Richard King 2

You know the old saying....."You get what you paid for" right.  It's to bad people don't ask about the machines on the forum before they invest money is these pits...lol  But they fill a knitch  ...sighhhhhhhhhhhh


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## Richard King 2

Andy you did a fine job after a lot of trial and error.  I am looking forward to your next project.   The first one is always the hardest.  Like my Dad used to say.  "You learn something everyday and when your done learning your dead" .  I say when you think you can't learn anymore your a fool as I learn everyday from people.   I recall when I was working on a Cincinnati Mill and I was under the knee installing a shaft.  My apprentice Gordy was helping me by handing me tools and helping support a shaft I was having issues with getting in.  I was under there what seemed an hour trying to get it in.   I had to go to the bathroom and got a cup of coffee, got up and and walked over and came back 5 minutes later and the shaft was in and Gordy was waiting.  I said how did your do that?  He said I slid it back and then it slid forward and bingo..  I shook his hand and we both had a big smile on our faces.   Thanks for showing the forum how to rebuild.    Rich


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## AndySomogyi

Got all the parts sanded and painted, working on the saddle oil system and assembly.

I had to re-design the oil system to address some design flaws, I’m putting together a video where I talk about the physics of fluid films and columns. I just make the occasional vid for fun, I don’t have a commercial account nor will I ever, so I don’t make a cent off this content. Anyways, some interesting physics in the oil system, but it’s pretty simple to explain, will try to get to that this week sometime.

painted all the parts using red oxide primer, and catalyzed Rustoleum that I mixed myself to match this color, used an HVLP gun. Very important to first shoot a light dust coat, let that flash off, then shoot the main color coat. The initial coat creates a sticky surface for the main coat to stick to and prevents runs and fisheye.

let the parts cure for a few days to harden, then verified dimensions. Checked and the knee is still square to within 0.0002, LOL, big improvement over the 0.0300 out of square that I started with.

But noticed the flange nut at the base didn’t line up correctly, and the lead screw was binding at the bottom, so enlarged the holes with a die grinder, and not it moves smooth.
The knee moved like butter using the lead screw. However there’s a bit of backlash in the gears that I don’t like. I’ll need to find some way to shave about 0.010 off that plate, but I don’t have a surface grinder so not sure how. I checked with the only local machine shop and they quoted me the usual “we don’t want your business price”, ha ha, the clowns wanted $1000 to slap a 6” plate on a surface grinder and shave a few thousands off it. I can buy a brand new benchtop surface grinder from China for just over $1000.


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## mattthemuppet2

nice work Andy!

I'd be interested in hearing about your replumbing of the oil lines. I want to add a couple of lines to oil the X and Y axis nut as well as putting in some check valves. Plus the RHS Z axis way doesn't get as much oil as the other points, so I want to take the knee off and figure out why. Then maybe add some DIY restrictors to some of the lines (eg. the X axis) that are getting too much oil.


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## AndySomogyi

mattthemuppet2 said:


> nice work Andy!
> 
> I'd be interested in hearing about your replumbing of the oil lines. I want to add a couple of lines to oil the X and Y axis nut as well as putting in some check valves. Plus the RHS Z axis way doesn't get as much oil as the other points, so I want to take the knee off and figure out why. Then maybe add some DIY restrictors to some of the lines (eg. the X axis) that are getting too much oil.


Thanks !

When you think about these oil systems, they’re a total loss oiler, and really the purpose of the pump is just to deliver oil as sort of an automated manual oiler. It’s really the surface tension between the oil and ways that holds the oil film in place, while your running it, the oil isn’t pressurized by the pump.

In a production env, sure it’s important to save oil, you wouldn’t want a bunch wasted each time you use the machine. But in a home machine, IMO, as long as the oil gets where it’s supposed to get, you’re fine, and I think it’s ok to have some excess spillage. Any excess oil will simply squeeze out of the ways and drop off.

On the BPs, I think the only restrictors they use are to the lead screw nuts, but I could be wrong.

In my case, I didn’t plumb the lead screw nuts, I think for now I’ll just keep them greased and eventually convert to ball screws and CNC.

Here’s what my oil lines look like now. The real trick was getting oil to the bottom Y ways, as the factory system never delivered any there.


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## AndySomogyi

Argh!!! More Grizzly stupidity that I had to repair !.

Got the new one-shot oiler all hooked up,  started testing it, and noticed oil gushing out from inside the knee.

I look inside and see two holes gushing oil, WTF 

Then I realize, the oil holes for the column ways ARE DRILLED ALL THE WAY THROUGH!

Take a look at the 4th pic here, that’s the back of the knee after scraping, notice the holes. Those are what I’m talking about .

Why???

How was this even working at all? I don’t know, was it always gushing oil? Did they have some bondo on the back that I knocked off cleaning it? Who knows? 

So I sure wasn’t going to take the knee off, so what I did was clean off the insides and JB Weld some plates there to cover the holes. After a few tries, seems to hold now.

But wow, that’s just insane drilling the holes through.


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