# A Vertical Slide For A 9x20 Lathe



## savarin

My first vertical slide was a bit small in what it could hold so I have decided to build a larger one.
It should look something like this (but not in these colours)


I faced and edged a chunk of hot rolled scrap for the front plate.
I will drill and thread a matrix of holes in this for a variety of mountings.


All four edges were also faced off in a similar manner and ended up within 0.001" of square on all sides and faces. It took a couple of attempts to get it this good.


the next job was to soak the 12mm plates for the angle and swivel plate in vinegar to remove the mill scale, 48 hours and it was cooked to perfection, a bit safer than hydrochloric acid.


The first mistake was to bore the plate for the swivel shaft too large, Doh! never mind, I just knurled the shaft to make it a tight fit. You can just see it there.
The worst part was how I managed to make it too large.
The shaft is 20mm, I turned down one end to 15mm which is where I wanted to fit the shaft.
I used the calipers to measure the shaft then checked that against some imperial drills, the first one I tried was larger than the set caliper gap so I said to myself - " no worries I can bore it out that little extra bit."
I have absolutely no idea why I thought this, definitely a senior moment.
I cut a large counter sink for extra weld holding. This side will eventually be faced flat.


First side welded but forgot to take a photo. 
Second side to be deep welded.


I cut the corners off the circle with the angle grinder first to make it easier to turn round.


I decided to turn it between centres to ensure the disk had parallel sides.
and that the shaft was at right angles.


I have decided to add a degree scale on the outside. I have no idea if this is worthwhile but it will look good.
To this end I have printed a degree scale onto a sheet of paper and stuck it to some stainless plate.
I will use this in the end of the main spindle to index the wheel.


This is printed at two degree intervals as I think one degree intervals will be a bit too close.
This site is an excellent source for printed scales
http://www.cgtk.co.uk/metalwork/reference/divider
I've run out of thin cutting disks so have to wait a bit before I can cut it out and lacquer it.
It is the same size as the face plate so I hope to be able to actually turn the what will be a rough cut edge smooth.


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## savarin

The stainless sheet is an unknown freebie.
Its 1.9mm thick and damned hard.
I had to resort to the "Bench" shears


I made a quick mandrel to chuck it up to skim the edge'


A complete waste of time, nothing would touch it. I had to resort to a file and hope.
Eventually it was done and I could mount it on the lathe using an expanding mandrel
Made a pointer, used a "G" clamp and steel chunk as a saddle stop (removed here) and worked my way around the disk,
re-adjusted the stop and went round again to extend the whole numbers.
Each division is 2 degrees.
It was pretty quick considering, about 30 mins total.
BUT..... What a dork! in my rush to get this done I marked the wrong edge, guess I will have to make a pointer instead of the mark I was going to use.


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## Mark_f

I have made that same mistake of marking the wrong edge. I just remachine  the edge and mark it correctly if you can have it about .015" undersized.


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## savarin

My brain must be turning to mush I cant believe I never thought of that 
thanks Mark.


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## savarin

Started to face the angle plate with the large fly cutter



Took 3 passes to get this far 


The top right corner didnt get touched but that will be cut off any way and the bottom right corner will be filed flat. Again it doesnt matter as its only cosmetic (but it still hurts)
I bored out the centre using a drill in the lathe spindle then had to mount a milling cutter very slightly off set in the 4 jaw to get the hole exactly to size.



The shaft the other side still has to be threaded for an 18mm nut to clamp the degree disk to the angle plate, then I can cut the shaft off this side.
The blue part has to be trimmed down to the graduated disk.
The shaft protruding from the disk will be removed next.


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## Eddyde

Looks good! Perhaps you can add a vernier scale to get divisions below the 2 degree marks?


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## savarin

I must be honest Eddy I dont really know if the degrees are worth while but thought it would look good.
I hadnt thought about a vernier scale, I will have to read up on how to do it and even more - how to read one.


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## savarin

A wee bit more done today.
Milled the curve in the angle plate to match the degree wheel.
I made a temp mandrel to hold the angle plate on the and turned it by hand.



I cut most of the excess off with an angle grinder, milled it then resorted to the file to finish. Still needs a bit more smoothing.


You will notice Mark that I didnt re cut the scale (lazy sod) I will make a little brass pointer to also hide some of the rough marks.


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## savarin

In my usual clumsy manner I broke a tap in the main block.
This required re winding the eroder coil.
Done that and have commenced to burn the broken tap out.
This pic shows the burner in operation but I've lowered the flushing oil (kero) to show up.


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## savarin

Burnt the tap out, took a bit of work to chip out the remaining threads but ended up with the original threaded hole un damaged. Just had to run the tap through to clean it up.
Whilst the eroder was burning I milled the flats on the nut.
Many thanks to Tony for kicking me in the butt, I re-assembled the small vertical slide as its accurate enough for this job.



the nut in place, worth $20 of any ones money.



Then I went on to mill out the slot in the slide block.
Phew, this chattered like mad but worked.


This is half way through so now I have to flip it to finish the other side.


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## savarin

Back from holiday for a week before I could scrounge some shed time.
Still it was worth it as I got a fair bit done today.
Finished all the milling and tapping in that damned block. I broke 2 more 4mm taps so I re drilled and tapped them all for 5 mm instead of 4 mm.
The eroder worked overtime and I found that it actually constricted the centre of the coil causing it to slow from friction. I turned down the armature to get more freedom and the speed virtually doubled and the coil didnt get as hot.
A win win situation, just trying to find a bright spot from all the broken taps

Here is the finished block bolted to the pivot plate with all those cursed threaded holes.



As I needed a plate for the slide to er slide on I had to cut some 10mm plate down so I faced one edge for a datum line


Then I could cut the excess off with the angle grinder and use this flat edge butted to the chuck to finish the cut side parallel. (which turned out to be the case)


Next it was the ends turn, hmm a fair bit of overhang but slow and gently and I ended up with the ends at exact (as best as I could measure) right angles.


Then of course it had to be faced off. Simple


I used a bolt turned to a point to make registration marks, drilled and bolted one, adjusted and marked and drilled a second diametrically opposite and bolted up before marking all the others.
It worked and they all lined up


Holes drilled and bolted onto the degree wheel and block.
Now I really have to decide upon whether to keep it as a gingery style gib or cut the 60' angles for a dovetail.
Dovetails will require the assistance of a mates mill that in this case I cant avoid as there is insufficient cross slide travel to cut them in my lathe.
It will end up with a fair bit of overhang that I'm hoping can be improved with the use of a machinists jack.


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## savarin

Finished drilling and tapping 33 holes in the main plate for a variety of fittings.
The 8mm sets of three holes are for the jaws, the 6mm holes along each edge are for clamps to hold a small engineers vice


Just for a grin I went back and faced it with a shearing bit. Thats a lot of fine swarf.


It left a better finish that I started with but the centre was a bit smeared.
The bottom jaw is drilled and sized, the top jaw for the vice is tomorrows job.


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## Randall Marx

Looking good. I've been enjoying reading through your progress and seeing how you overcome what might be considered to be a lack of equipment. Thank you for sharing your journey with us!


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## savarin

Thanks for the kind words Randall. much appreciated.


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## jocat54

Savarin, You always amaze me with what you can do with lathe.
Great work!


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## Silverbullet

You have a great can do knack  , your work with just a small hobby lathe shows the talent you have as a machinist. Good job


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## savarin

Thanks guys, most appreciated.
BUT! I am only an old chef who definitely can not be called a machinist, I would call it "Seat of the pants fabricating"
Not having been shown how to do the right thing I just plough ahead and give it a try, doesnt always work though.


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## savarin

Just spent three days adjusting the tail stock to get as perfect as I could straight cut over a 250mm length.
This will be for the lead screw.
I managed to get it down to 0.00017" difference from one end to the other (Translated from my mm micrometer)
I though this was as good as it gets, but, the middle was about 0.0008" fatter.
I did all this between centres turning some 20mm dia unknown steel down to 10mm (it was bright and shiny on the outside)
Turning this unknownium was a real ***** as it kept tearing and producing a very rough surface, worse than hot rolled mild steel, so I experimented with differing grinds, speeds and feeds till I ended up cutting almost at the slowest the lathe would turn and a very very slow feed. This produced an acceptable finish.
In an attempt to remove the fatter central section I tried a travelling steady.
What a pita these are, but it sort of improved it slightly (guess I need a lot more practice here)
Now its cutting nicely I reduced the bar to its final dia of 10mm and proceeded to single point the 1mm thread.
ARGH, I set the gear box to 6 instead of 7, good job it was just the scratch cut, reset to the correct number and started cutting (with the travelling steady set)
I ended up with the most horrendous thread I have ever seen or cut myself.
There were nice sections, fat sections, sections with torn thread crests and every other stuffup you can imagine in that 200mm length of thread.
I'm sure this is the same steel I used for the indexing wheel above and that thread was single point cut and is excellent.
Back to square one on this.


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## HBilly1022

It absolutely AMAZES me what you do with an "Asian 9x20, some rusty files and a hammer". I've had my Asian 10 x 20 lathe for about a year now and I think I'm just starting to figure out how much I need to learn. Then I see your posts and I know there is hope. However I never expect to get to your level. You produce some incredible work and I don't see how it would turn out any better using an expensive lathe.

I know what you mean about turning the same piece of steel with different results. Just when you think you have it figured out and your getting a nice finish, _something_ changes and it all goes for a ****. This is the one thing I struggle with the most. It keeps things interesting and frustrating but we will overcome.

EDIT, I just thought of something. If you are cutting _threads_ and using the following steady, could that cause distortion because the steady is riding on the threads and pushing the work piece back and forth (up and down) as it rides on the threads? I guess it depends on the contact surface area. If the contact is pointed then it would follow the threads, if it was over a longer length, it would follow the surface (tops) of the threads.

I'm not experienced so I could be out in left field on this.


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## savarin

HBilly1022 said:


> If you are cutting _threads_ and using the following steady, could that cause distortion because the steady is riding on the threads and pushing the work piece back and forth (up and down) as it rides on the threads? I guess it depends on the contact surface area. If the contact is pointed then it would follow the threads, if it was over a longer length, it would follow the surface (tops) of the threads.


Yep, I assumed it would ride over the crests and prevent the thread from being pushed away from the bit.
I hated using it as it seems like a bit of a cludge and the fingers definitely wore away a tad.
I used a file to remove any sharp bits that may have been left after every cut in the hope that would have helped.


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## savarin

Had a better day today.
I cleaned up the horrible thread with a small triangular file till it fit, its still horrible with torn bits but it does work and as the section it screws into has a long thread its actually quite smooth in action much to my surprise.
At least I now have real measurements to make a new one from. (gotta look on the bright side.



All screwed up, the top aluminium section with the bearings will bolt to the top of the plate with all the mounting holes.


The small top hat section clamps to the centre of the top roller bearing and will have a round dial marked in 1/10's with a friction sliding fit so if I need to be accurate with the slides movement I can.
The handle (when I can decide upon a shape) will be pinned to the top of the top hat and held with the dome nut.
Now back to the gibbs.


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## savarin

Next to set out the holes for the top bracket.
I set all the parts up and used c/sunk screws to hold the slide plate in the correct position as the gibbs are not ready yet.
The centre bolt was turned to a point and the top bracket lowered via the lead screw, aligned and a mark made.
Drill, remove the point and move to the next hole, use the bolt to align and repeat till all three are done




The top hat shape then had a couple of grooves added for "O" rings to add a tight  friction fit to the knurled scale.
Each division is 1/10 of a millimetre movement.


The movement is nice and smooth and the scale turns with the screw but can be manually set to the number.
Those three bolts pass down into the main slide block.









Hopefully if I'm allowed some shed time its the handle tomorrow.
I'm a tad concerned about the amount of metal hanging out from the cross slide so I may have to add some extra support once in place but am unsure how at this moment in time.


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## savarin

or some reason this post disappeared into the aether so I try again.
I was going to pin the top hat section to the shaft when I suddenly realised that the scale ring would prevent that DOH!
So I made a small cutter to broach out a keyway.


Flipped the broach over to key the shaft


I suppose I could have continued the keyway along the threaded portion to key the handle as well but decided to use three pins instead.
The handle is a rescue from another old project and as the ball end wouldn't unscrew I had to keep the length so I could grip it in the chuck as I didnt want to mar the shiny ball.
The disk was again a scrap that I drilled out five holes and knurled the edge. The small brass key was cut from a sheet and filed to size.



All back together and works very smoothly with the c/sunk screws instead of gibb strips. Almost to the point of just using those, but I wont.



Now I just need some time to arrange the friends mill to finish the gibbs.


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## savarin

Gibbs and dovetail milled, assembled with "G" clamps and it works.
Only had an hour free so that was all I managed to do today.


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## rwm

That's amazing. Awesome fabricating.
Robert


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## savarin

As the side without the adjusting screws had room to access the 6mm through threaded holes I used them to fix that dovetail.
A bit over the top maybe but no threading to do. 



I'm not so lucky on the other side with the brass gibb strip as it occludes part of the existing holes.
You can see the six screws at the top of the unit.
The photo makes the dovetail that the brass is against look vertical but its actually cut at 30 degrees.
I will drill and tap new fixing holes between the existing holes but only halfway through the block at 5mm.
I guess this is what happens when the main drawings are just carried in your head.


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## Downunder Bob

Nice job Savarin, you do some nice work, hard to believe your not formally trained. How long have you been self learning. It's quite amazing what you can make with just a lathe and a lot of ingenuity. you also have the advantage of not having been taught what can't or shouldn't be done, something I've had to unlearn when faced with that impossible job, learning to think outside the box is very useful at times.

Bob


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## savarin

bobshobby said:


> Nice job Savarin, you do some nice work, hard to believe your not formally trained. How long have you been self learning. It's quite amazing what you can make with just a lathe and a lot of ingenuity. you also have the advantage of not having been taught what can't or shouldn't be done, something I've had to unlearn when faced with that impossible job, learning to think outside the box is very useful at times.
> 
> Bob


Thanks Bob, Ive been making "stuff" all my life from a very early age with mecanno and other construction sets. I can visualise most things in 3d  I just needed some basic tools to fabricate what I wanted.
This is my first lathe  so I now have three years of basic machining experience that includes some monumental stuff ups but thats what learning is all about.
I used to tell my students that they can do anything, they just have to think first then have a go.
It didnt matter if it didnt work as they would still learn heaps. I try to live by this mantra.


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## Downunder Bob

savarin said:


> My first vertical slide was a bit small in what it could hold so I have decided to build a larger one.
> It should look something like this (but not in these colours)
> View attachment 134262
> 
> I faced and edged a chunk of hot rolled scrap for the front plate.
> I will drill and thread a matrix of holes in this for a variety of mountings.
> View attachment 134260
> 
> All four edges were also faced off in a similar manner and ended up within 0.001" of square on all sides and faces. It took a couple of attempts to get it this good.
> View attachment 134257
> 
> 
> Interesting, one of the first things we were taught at trade school was to face a hunk of steel on all sides and edges, keeping it square and flat. I see you've learned the process well. We eventually finished up with an engineer's "C" clamp, making all the parts by various processes.
> 
> the next job was to soak the 12mm plates for the angle and swivel plate in vinegar to remove the mill scale, 48 hours and it was cooked to perfection, a bit safer than hydrochloric acid.
> View attachment 134263
> 
> The first mistake was to bore the plate for the swivel shaft too large, Doh! never mind, I just knurled the shaft to make it a tight fit. You can just see it there.
> The worst part was how I managed to make it too large.
> The shaft is 20mm, I turned down one end to 15mm which is where I wanted to fit the shaft.
> I used the calipers to measure the shaft then checked that against some imperial drills, the first one I tried was larger than the set caliper gap so I said to myself - " no worries I can bore it out that little extra bit."
> I have absolutely no idea why I thought this, definitely a senior moment.
> I cut a large counter sink for extra weld holding. This side will eventually be faced flat.
> View attachment 134261
> 
> First side welded but forgot to take a photo.
> Second side to be deep welded.
> View attachment 134264
> 
> I cut the corners off the circle with the angle grinder first to make it easier to turn round.
> 
> About time you got a bandsaw, that poor angle grinder does way too much cutting work. I recently got a Hafco Metalmaster BS-5V Bandsaw, Widely available in Aus. very happy with it, they have  a range of models around that size.
> 
> 
> View attachment 134258
> 
> I decided to turn it between centres to ensure the disk had parallel sides.
> and that the shaft was at right angles.
> View attachment 134259
> 
> I have decided to add a degree scale on the outside. I have no idea if this is worthwhile but it will look good.
> 
> 
> To this end I have printed a degree scale onto a sheet of paper and stuck it to some stainless plate.
> I will use this in the end of the main spindle to index the wheel.
> View attachment 134256
> 
> This is printed at two degree intervals as I think one degree intervals will be a bit too close.
> This site is an excellent source for printed scales
> http://www.cgtk.co.uk/metalwork/reference/divider
> I've run out of thin cutting disks so have to wait a bit before I can cut it out and lacquer it.
> It is the same size as the face plate so I hope to be able to actually turn the what will be a rough cut edge smooth.


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## Downunder Bob

savarin said:


> Thanks Bob, Ive been making "stuff" all my life from a very early age with mecanno and other construction sets. I can visualise most things in 3d  I just needed some basic tools to fabricate what I wanted.
> This is my first lathe  so I now have three years of basic machining experience that includes some monumental stuff ups but thats what learning is all about.
> I used to tell my students that they can do anything, they just have to think first then have a go.
> It didnt matter if it didnt work as they would still learn heaps. I try to live by this mantra.



I can relate very well to that, I remember as a kid building quite a large crane with meccano, and the jib collapsed because it was not stiff enough, I learned a lot about mechanics from that and other projects.

I also find it easy to visualise in 3D, and even though tech drawing was my best subject in trade school I have always built most things from the image in my head, rarely ever bothering with a drawing.

You say your lathe is asian 9x20 does it have a brand, is it Chinese or Taiwanese?

I just got my first lathe 12 x 16 and am still setting it up. It's the first time I've been near a lathe or anything bigger than an angle grinder, for over 20 years, So I actually have a re-learning curve ahead of me. While I still remember much of what I knew, it's the fine touch of hands on the controls that I have to re-learn.

Stuff ups of any size is the core of learning, we always learn more from mistakes, than from successes. You are so very correct when you say just think of it first and give it a go,

What did you teach?


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## savarin

Professional cookery, food science, basic computing, food hygiene, HACCP for the catering industry.
The lathe is a generic Chinese purchased from Hare and Forbes. AL50, not sold any more.


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## Ulma Doctor

G'Day,
excellent work Sav!!!
your attention to detail and skill has rendered a wonderful tool
i admire your tenacity and imagination 
very well done


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## savarin

Thanks Mike, its finished, now I can finish the part I needed it for on the telescope.
I decided that a 4mm thread all the way through the gibb clamp was asking for trouble so I drilled all the way with the clearance drill for the thread then drilled a 4mm hole from the other side leaving only 6mm for the thread. The space being taken up with 4mm dia steel pins bearing onto the brass strip.
I then marked the brass strip and attempted to mill flat pockets for 4mm flat pins to sit in so the brass strip couldnt move in any direction. It worked, sort of, but the 4mm end mill did a horrible job and wobbled/flexed producing a larger hole than I anticipated. I went down this route as a test for when I try to improve the lathe cross slide as thats either too tight to move or too loose and lifts.



Here you can see how bad the pockets really are, but all the pins sit in them no problems.


It all bolted up and adjusted to produce a very smooth action with no discernible play.
The lead screw has approx 1/125thmm of backlash in the thread that I didnt even notice untill all the gibb screws were tightened to a very stiff action.
Considering how bad that thread was cut thats not badd. I will make another when I get some good steel.



The pivot plate bolted on


Its now ready to test hopefully this arvo.


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## savarin

Mounted on the lathe and checking it out for squareness.
Pressed up against the face plate its three thou out at the base of the slide.
Can anyone do the trig to calculate how thick a shim I would need under the front of the angle plate to bring it into square?
My math is not up to this.
the mounting plate is 6" long


Here I'm adjusting the angle of the slide to ensure it traverses  exactly horizontally so I can mark the "0"  point for the degree wheel.
Thats all I had time for today, not even a trial cut.


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## Downunder Bob

savarin said:


> Thanks Mike, its finished, now I can finish the part I needed it for on the telescope.
> I decided that a 4mm thread all the way through the gibb clamp was asking for trouble so I drilled all the way with the clearance drill for the thread then drilled a 4mm hole from the other side leaving only 6mm for the thread. The space being taken up with 4mm dia steel pins bearing onto the brass strip.
> I then marked the brass strip and attempted to mill flat pockets for 4mm flat pins to sit in so the brass strip couldnt move in any direction. It worked, sort of, but the 4mm end mill did a horrible job and wobbled/flexed producing a larger hole than I anticipated. I went down this route as a test for when I try to improve the lathe cross slide as thats either too tight to move or too loose and lifts.
> View attachment 139640
> 
> 
> Here you can see how bad the pockets really are, but all the pins sit in them no problems.
> View attachment 139643
> 
> It all bolted up and adjusted to produce a very smooth action with no discernible play.
> The lead screw has approx 1/125thmm of backlash in the thread that I didnt even notice untill all the gibb screws were tightened to a very stiff action.
> Considering how bad that thread was cut thats not badd. I will make another when I get some good steel.
> View attachment 139639
> 
> 
> The pivot plate bolted on
> View attachment 139641
> 
> Its now ready to test hopefully this arvo.



Quite an amazing build  Savarin, but I'm a little intrigued by the measurement of 1/125th mm. I've not previously heard of that as a dimension, nor seen anything calibrated that way, I'm familiar with 128th inch but as all your other dimensions are in mm I'm not thinking it's a typo. However, well done.


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## savarin

bobshobby said:


> Quite an amazing build  Savarin, but I'm a little intrigued by the measurement of 1/125th mm. I've not previously heard of that as a dimension, nor seen anything calibrated that way, I'm familiar with 128th inch but as all your other dimensions are in mm I'm not thinking it's a typo. However, well done.



Thanks Bob, that measurement was a best guess extrapolating from the scale at the handle.
Each division of the scale represents 0.1 mm of travel so as the screw moves approx 1 and a quarter divisions from one way to the other before it "bites" I took that as the best guess.
My brain worked it as one tenth of a mm plus a quarter of a tenth, weird I know but thats how it is.
One full revolution travels one mm.
Now you can see why I need someone else to work out the trig to get the tilt back for exact vertical else its back to t&e


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## hman

savarin said:


> Mounted on the lathe and checking it out for squareness.
> Pressed up against the face plate its three thou out at the base of the slide.
> Can anyone do the trig to calculate how thick a shim I would need under the front of the angle plate to bring it into square?
> My math is not up to this.
> the mounting plate is 6" long


OK, let's be sure I understand things.  You ran the carriage toward the head until the slide was against the face plate, and found that there was a .003" gap on the lower end ... ya?

If so, you don't need trig, just proportions.  You know that the slide and faceplate are out by .003" over the length of the slide.  Let's call it L.  The mounting plate is 6" long.  The proportions will be .003"/L = SHIM/6", where SHIM is the thickness of the shim you'll need between the mounting plate and what it's mounted to.  If the mounting plate is held against something that's less than 6" long, use that figure instead of the 6" in the above calculation.

Hope this makes sense.

<Quoting again>
Thanks Bob, that measurement was a best guess extrapolating from the scale at the handle.
Each division of the scale represents 0.1 mm of travel so as the screw moves approx 1 and a quarter divisions from one way to the other before it "bites" I took that as the best guess.
My brain worked it as one tenth of a mm plus a quarter of a tenth, weird I know but thats how it is.
One full revolution travels one mm. <end quote>

Your measurement would be 0.125mm (⅛ mm), not 1/125 mm.  


By the way, this has been a _*fantastic*_ build to watch, and kudos to you for your so far excellent results!


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## savarin

hman said:


> Let's call it L.  The mounting plate is 6" long.  The proportions will be .003"/L = SHIM/6", where SHIM is the thickness of the shim you'll need between the mounting plate and what it's mounted to.  If the mounting plate is held against something that's less than 6" long, use that figure instead of the 6" in the above calculation.
> 
> Hope this makes sense.



Err, if you mean 0.003/6 = 0.0005 and thats the thickness of the required shim then yes.
I think some experimenting is required to get a shim that thin.



> Your measurement would be 0.125mm (⅛ mm), not 1/125 mm.



DOH!  I cant believe I put that in print



> By the way, this has been a _*fantastic*_ build to watch, and kudos to you for your so far excellent results!



Thank you so very much John, that is much appreciated.
except for the shim to get the tilt corrected I got it squared up today and marked the zero degrees.
Cross drilled my long boring bar for a cutter midway ready to get back to the telescope build.


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## hman

I think you may have misunderstood what I was saying, or I misunderstood your terminology.  So I did a couple of quick 3D renderings of what I *think* is going on with your slide.  They're very "generic," as I don't know the exact construction details of your slide assembly.  But I hope they're understandable.

Both diagrams show the faceplate (grey object on left) and the face of the slide (tan object next to it), with the 0.003" gap (exaggerated) at the bottom.  The first diagram assumes that you'll want to put the shim between the base of your slide assembly and the plinth (most likely the cross slide of your lathe, shown as a pink object at the bottom).  The second assumes that you want to put the shim between a vertical support of your slide (blue object) and some other slide part. 

Both of the diagrams show the height of the slide face as having dimension "H".  Both of them show the contact area to be shimmed as having dimension "L".  On both diagrams, the location and thickness of the required shim is shown as "SHIM".

Here are the diagrams:


OOPS!!! SHIM is shown at the wrong end of the plinth!  Should be at the end nearest the faceplate.





The thickness of the shim comes from proportions - 0.003"/H = SHIM/L
-or-
SHIM = 0.003" * H / L

Hope this is understandable!  Do ask for clarification if it isn't.


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## Downunder Bob

hman said:


> OK, let's be sure I understand things.  You ran the carriage toward the head until the slide was against the face plate, and found that there was a .003" gap on the lower end ... ya?
> 
> If so, you don't need trig, just proportions.  You know that the slide and faceplate are out by .003" over the length of the slide.  Let's call it L.  The mounting plate is 6" long.  The proportions will be .003"/L = SHIM/6", where SHIM is the thickness of the shim you'll need between the mounting plate and what it's mounted to.  If the mounting plate is held against something that's less than 6" long, use that figure instead of the 6" in the above calculation.
> 
> Hope this makes sense.
> 
> <Quoting again>
> Thanks Bob, that measurement was a best guess extrapolating from the scale at the handle.
> Each division of the scale represents 0.1 mm of travel so as the screw moves approx 1 and a quarter divisions from one way to the other before it "bites" I took that as the best guess.
> My brain worked it as one tenth of a mm plus a quarter of a tenth, weird I know but thats how it is.
> One full revolution travels one mm. <end quote>
> 
> Your measurement would be 0.125mm (⅛ mm), not 1/125 mm.
> 
> 
> By the way, this has been a _*fantastic*_ build to watch, and kudos to you for your so far excellent results!




That's more like it.


savarin said:


> Err, if you mean 0.003/6 = 0.0005 and thats the thickness of the required shim then yes.
> I think some experimenting is required to get a shim that thin.
> 
> Savarin, you might find a source of thin shims at the auto parts shop, or try some cheap feeler gauges just pull them apart to get .0005 put a .001 at one end and a.0015 at the other end, or other sizes to suit. A set of feelers probably cost less and is easier to find than a small sheet of shim.
> 
> 
> 
> DOH!  I cant believe I put that in print
> 
> 
> 
> Thank you so very much John, that is much appreciated.
> except for the shim to get the tilt corrected I got it squared up today and marked the zero degrees.
> Cross drilled my long boring bar for a cutter midway ready to get back to the telescope build.


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## rwm

Just a thought. Instead of shimming it could you re-cut the face to get it perfect? Also, could it be that your cross slide is off my 0.003?
Robert


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## savarin

I used the first example and went back to mm.
Re done the calcs and they come out to almost the seat of the pants one I did.
My guess went along the lines of if I tilt the plate by half the gap it should move the top out almost the same amount and bring it into alignment.
I guessed a .15mm would work whereas it came out to .141.
An achievable shim size.
Many thanks.


rwm said:


> Just a thought. Instead of shimming it could you re-cut the face to get it perfect? Also, could it be that your cross slide is off my 0.003?
> Robert


I will check the cross slide as that is a distinct possibility on this machine.
I really dont want to re cut the face at this time but definitely a future task.


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## savarin

The cross slide is spot on so no probs there.
Whoo hoo, the .14mm shim (.08+.06) worked perfectly, absolutely spot on.
First task was to drill my boring bar so I could add a cutter in the middle.
I've done the 6mm this is the 3.3mm for the 4mm grub screw to hold the cutter.



The second session was a test cut to profile a 10 mm thick aluminium section at a radius of 45mm.
Very smooth cut that fit onto a 90mm dia section of the telescope. 
Thats a lot of tool overhang.
Now I can cut the brackets to fit the scope.


The saga will continue here:-
http://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/page-4#post-409720


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## rwm

Amazing work. As you may remember I sold my Asian 9x20 for a larger lathe so it is very impressive to me to see all you can do with it! 
Robert


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## savarin

Thank you Robert.


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## Downunder Bob

savarin said:


> The cross slide is spot on so no probs there.
> Whoo hoo, the .14mm shim (.08+.06) worked perfectly, absolutely spot on.
> First task was to drill my boring bar so I could add a cutter in the middle.
> I've done the 6mm this is the 3.3mm for the 4mm grub screw to hold the cutter.
> View attachment 139773
> 
> 
> The second session was a test cut to profile a 10 mm thick aluminium section at a radius of 45mm.
> Very smooth cut that fit onto a 90mm dia section of the telescope.
> Thats a lot of tool overhang.
> Now I can cut the brackets to fit the scope.
> View attachment 139774
> 
> The saga will continue here:-
> http://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/page-4#post-409720



I'd like to see that cutter in  action.


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## savarin

no video Bob but the results of four passes here.
http://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/page-4#post-436866
second from last post on that page.


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## Downunder Bob

savarin said:


> no video Bob but the results of four passes here.
> http://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/page-4#post-436866
> second from last post on that page.



Some more of your amazing quality work, the finish is amazing given the length of that tool bit and the distance from the chuck, did you get any springing in that setup?

I'm going to have to work hard to catch up to you, you continue to set a high standard.


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## savarin

bobshobby said:


> the finish is amazing given the length of that tool bit and the distance from the chuck, did you get any springing in that setup?


Not that I noticed or lets be honest - that I looked for.
I did this first on some parts for the central pier of the telescope, on brass and stainless. These didnt appear to cause any problems then.



> I'm going to have to work hard to catch up to you, you continue to set a high standard.


Thanks but it wont be that difficult, look at how long it takes me.


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## Downunder Bob

savarin said:


> Not that I noticed or lets be honest - that I looked for.
> I did this first on some parts for the central pier of the telescope, on brass and stainless. These didnt appear to cause any problems then.
> 
> 
> Thanks but it wont be that difficult, look at how long it takes me.



You still beat me I've done nothing for a week. I'm a bit distracted at the moment, my wife had a stroke last week, so I'm spending most of my time at the hospital.


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## hman

bobshobby said:


> You still beat me I've done nothing for a week. I'm a bit distracted at the moment, my wife had a stroke last week, so I'm spending most of my time at the hospital.


Best wishes to you both, and I hope she recovers fully!  My wife had a stroke in '12, and I know it can be a difficult time.


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## savarin

Really sorry to hear that Bob, my best wishes for a full recovery.


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## savarin

bobshobby said:


> I'd like to see that cutter in  action.


Ask and it shall be done




I'm a bit disappointed in that in the original clip you can see the lip move across as the cut progresses but cant on youtube.
This is just a chunk of hotrolled mild steel just to show before I removed the vertical slide.


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## Downunder Bob

savarin said:


> Ask and it shall be done
> 
> 
> 
> 
> I'm a bit disappointed in that in the original clip you can see the lip move across as the cut progresses but cant on youtube.
> This is just a chunk of hotrolled mild steel just to show before I removed the vertical slide.



Tried to play your video, but it's youtube and I don't have an account. never mind it's not important.


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## rwm

I think you need to change the permissions on that video to Public.
R


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## savarin

try now.


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## Downunder Bob

bobshobby said:


> Tried to play your video, but it's youtube and I don't have an account. never mind it's not important.



Thanks Savarin, you can just see the cut progressing if you go to full screen, very neat. What i like is that because you were never taught that you should not have so much tool overhang you just make it work. Whereas those of us with formal training would never even try it. Beginning to learn that our teachers didn't always get right. They were probably taught from someone even older who had learned on older machines that were probably less rigid that it won't work. I like your enthusiasm to get it done, often creates viable shortcuts, that we'd never think of. Keep it up.


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## savarin

Thanks Bob, as a typical example of what you are saying in my trade.
The classic Bechamel sauce (white sauce) is written in every recipe book as 100g flour, 100g butter to every 1l milk.
Yes it works but produces a sauce like concrete.
add more butter and cut down the flour to 80g and you get a smoother usable sauce.
But no apprentices were ever taught that.


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## Downunder Bob

savarin said:


> Thanks Bob, as a typical example of what you are saying in my trade.
> The classic Bechamel sauce (white sauce) is written in every recipe book as 100g flour, 100g butter to every 1l milk.
> Yes it works but produces a sauce like concrete.
> add more butter and cut down the flour to 80g and you get a smoother usable sauce.
> But no apprentices were ever taught that.



Exactly, I've long believed that a recipe is only a starting point, A good cook / chef should then experiment to perfect their own style. In the same way that you are not formally trained in machining, I'm not trained in cooking, but I do enjoy it. 

As a child I learned the basics from my mother, and have been experimenting ever since.


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## Ulma Doctor

great out of the box thinking Sav!!!

i have read this before. maybe it is apropos...

those who do not know what cannot be accomplished, are free to accomplish anything.


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