Restoration of my Schaublin SV52 toolroom milling machine

Jan,

Looking good! As you checked the column and it was reading so good, I think it was riding on the unworn oil groove area. Remember I teach "remove all ridges first". How deep are your scrape marks? Look like chicken scratches to me. :thinking:

Be sure to always put the adjusted level to the same end of your alignment bar. I like to mark it with a marker. Just in case you get tired and forget. All in all It looks excellent. Have to thank Tommy again for letting us use his shop. That was one of the memorial classes I have had. Rich
 
Richard King said:
Jan,

Looking good! As you checked the column and it was reading so good, I think it was riding on the unworn oil groove area. Remember I teach "remove all ridges first". How deep are your scrape marks? Look like chicken scratches to me. :thinking:

Be sure to always put the adjusted level to the same end of your alignment bar. I like to mark it with a marker. Just in case you get tired and forget. All in all It looks excellent. Have to thank Tommy again for letting us use his shop. That was one of the memorial classes I have had. Rich[/QUOTE

Hi Rich,

will dig in and try to avoid "chicken scratchin" , can also mike the depth
thought i give my new/old biax a try on the column ways, i can run this with a variac and tune the rpms to match my skill level

I had a fantastic week down there, and i will remember and miss it.
if i have the chance i may come again

that also goes for another class, if i can get things going workwise and afford it
Click to expand...
 
Figured I had no more excuses for not starting to scrape, I hit it..

After 3 passes each way with the old Biax, rpms down, but trying to dig in (still needs to practice sharpening the blades and honing the flats, and have a better setup), roughing technique, ie. circles, I start getting coverage from top to bottom, but still nothing at the worn area on the left way

Just because I was curious, I checked the parallelism also (before turning in at night).. the total error was down to less than 1 line (as compared with 2,5-3 before)! Wow! Actually for all but the lowermost reading it was within half a line on the level. If my math is correct this should be less than 2 tenths (or around 1 if you don’t count the very lowest area)

My scrapes with the Biax are in average 2-3/1000 mm, ie. a little shy for a roughing cut.
PS! The blades I have used are with a larger than optimal radius for a beginner skill level.. The plan is to purchase a set of Dapra holders with integral blades, but at the moment I must make do with what I have
Seems to be OK anyway.

Next day..
Thought I show you after some more passes, and some scraping- and blueing action with results
I know I put my head on the block so to speak (like standing up in class and answering to the teacher..), but feel free to comment on my technique (or lack of it), improvements/errors seen etc.

PS! The amount of blue shown in the end (last video) is somewhat excessive (at least compared with previous pics), but since I’m still roughing, I guess OK.
The white polka dots on the rear side of the blueing bar (was part of a Johanson CMM) are felt pads I used for 3 point contact when the bar is stored away
I was also brushing the chips/scrape-offs to the middle.. evidence that some material has come off
Yes.. the hearless head always blocking the shot belongs to yours truly..

http://www.youtube.com/watch?v=gQNOBaBh1C0&feature=youtu.be
http://www.youtube.com/watch?v=Il1fsbg8Wjw&feature=youtu.be

The mill column is actually at a convenient height to hip-scrape with a manual scraper, but for power scraping I found it necessary to either sit down or be at my knees. I tried to remember to keep the Biax tucked in well, horizontal and move it sideways with hip action.

I also made another parallelism test with the sled and level, and now the error is 2-3 lines (again), ie. apprx. within 4 tenths for the whole 33 inch length (I guess most 3 tenhts per foot), so still OK

I must also do the X-check both ways, as well as comparing against the spindle/dummy spindle. After some thought, this may require the whole spindle-column inserted again, using the spindle with an indicator on a test bar. However, to rotate the spindle in this vertical placement, it will have to rest against some dead-flat and rigid surface (when in normal use, the weight is not an issue, and I reckon the spindle is not rotated while milling, only in between as part of an angular setup, either freely rotating it to any setting or in the 15 degrees steps with lock), then locking down the whole spindle-column. This issue may lead me to make a setup, say a square test bar (adequately flat) that can ride on the lip just inside the big bore and the indicator on the end moved sideways.. I am not sure.

PS! For the observant viewer, I made a blunder with the last (for the camera action) scraping cycle.. doing it the same direction/angle as the former. Well, I guess it evens out, but the point with the marking with a pen was just that, to avoid those mistakes..

The vids are non-edited, but I suppose I ought to cut down lengthy sequences and put comments in..
 
jshaugjord said:
Figured I had no more excuses for not starting to scrape, I hit it..

After 3 passes each way with the old Biax, rpms down, but trying to dig in (still needs to practice sharpening the blades and honing the flats, and have a better setup), roughing technique, ie. circles, I start getting coverage from top to bottom, but still nothing at the worn area on the left way

Just because I was curious, I checked the parallelism also (before turning in at night).. the total error was down to less than 1 line (as compared with 2,5-3 before)! Wow! Actually for all but the lowermost reading it was within half a line on the level. If my math is correct this should be less than 2 tenths (or around 1 if you don’t count the very lowest area)

My scrapes with the Biax are in average 2-3/1000 mm, ie. a little shy for a roughing cut.
PS! The blades I have used are with a larger than optimal radius for a beginner skill level.. The plan is to purchase a set of Dapra holders with integral blades, but at the moment I must make do with what I have
Seems to be OK anyway.

Next day..
Thought I show you after some more passes, and some scraping- and blueing action with results
I know I put my head on the block so to speak (like standing up in class and answering to the teacher..), but feel free to comment on my technique (or lack of it), improvements/errors seen etc.

PS! The amount of blue shown in the end (last video) is somewhat excessive (at least compared with previous pics), but since I’m still roughing, I guess OK.
The white polka dots on the rear side of the blueing bar (was part of a Johanson CMM) are felt pads I used for 3 point contact when the bar is stored away
I was also brushing the chips/scrape-offs to the middle.. evidence that some material has come off
Yes.. the hearless head always blocking the shot belongs to yours truly..

http://www.youtube.com/watch?v=gQNOBaBh1C0&feature=youtu.be
http://www.youtube.com/watch?v=Il1fsbg8Wjw&feature=youtu.be

The mill column is actually at a convenient height to hip-scrape with a manual scraper, but for power scraping I found it necessary to either sit down or be at my knees. I tried to remember to keep the Biax tucked in well, horizontal and move it sideways with hip action.

I also made another parallelism test with the sled and level, and now the error is 2-3 lines (again), ie. apprx. within 4 tenths for the whole 33 inch length (I guess most 3 tenhts per foot), so still OK

I must also do the X-check both ways, as well as comparing against the spindle/dummy spindle. After some thought, this may require the whole spindle-column inserted again, using the spindle with an indicator on a test bar. However, to rotate the spindle in this vertical placement, it will have to rest against some dead-flat and rigid surface (when in normal use, the weight is not an issue, and I reckon the spindle is not rotated while milling, only in between as part of an angular setup, either freely rotating it to any setting or in the 15 degrees steps with lock), then locking down the whole spindle-column. This issue may lead me to make a setup, say a square test bar (adequately flat) that can ride on the lip just inside the big bore and the indicator on the end moved sideways.. I am not sure.

BTW! I did make some checks with the level (not the one I keep adjusting..) X and Y on the face of where the spindle column sits, so as I move along with the scraping I can use this as reference

PS! For the observant viewer, I made a blunder with the last (for the camera action) scraping cycle.. doing it the same direction/angle as the former. Well, I guess it evens out, but the point with the marking with a pen was just that, to avoid those mistakes..

The vids are non-edited, but I suppose I ought to cut down lengthy sequences and put comments in..
Click to expand...

Back to work..
 
Thanks for letting us follow along. It takes a lot of fortitude to handle something like this, especially the first time, but it looks like you are well on your way. You mention that you had your bluing kinda thick; I found that actually helped when roughing things out. On my first attempt I was applying it way too lightly, which caused me lots of problems.

As far as sharpening, I had pretty good luck with a small super-fine diamond hand lap. I would place it on the bench, then hold the scraper, handle up. Then I would draw the scraper toward me, following the arc of the blade.

I also recall seeing plans in one of the machinist magazines where the author build a rotary lap using a bench grinder, and machining a cast iron disk to fit in place of the grinding stone. The disk was then charged with diamond lapping compound.
 
DMS said:
Thanks for letting us follow along. It takes a lot of fortitude to handle something like this, especially the first time, but it looks like you are well on your way. You mention that you had your bluing kinda thick; I found that actually helped when roughing things out. On my first attempt I was applying it way too lightly, which caused me lots of problems

As far as sharpening, I had pretty good luck with a small super-fine diamond hand lap. I would place it on the bench, then hold the scraper, handle up. Then I would draw the scraper toward me, following the arc of the blade.

I also recall seeing plans in one of the machinist magazines where the author build a rotary lap using a bench grinder, and machining a cast iron disk to fit in place of the grinding stone. The disk was then charged with diamond lapping compound.
Click to expand...

Hi there, thanks for replying.
Yes, I knwo re. the blueing.. can be troublesome to see if using too little. I just thought I had applied somwhat more than I should have, spots becoming a little "smeared out". Looking closer, I can see they are not, so I was good.

I also tried that technique, also with a diamond lap, but had less success than you and never really got the hang of it. I will however make myself a simple honer, using a small motor, driving a diamond wheel at a low speed. A friend of mine made a nice one where the motor sits on a piece of aluminium U-bracket, then a table (also alu bracket) hinged to the motor bracket so you could set the table at angles. Real simple, though I think I will make adapter with set angles instead..just cut-offs that can be bolted/slid in place in fron of the wheel
 
Hi again,

Just to explain more on the alignment of the ways in relation to the spindle on this type of mill.
(I know, I am an engineer and tend to over-analyse things..)
Before starting the scarping, I set up the level on the rim of the hole which the spindle-column normally occupies.
I reason that the best practise (text-book style) would be to have the spindle in-place, and attach an indicator to this and rotate the spindle so it sweeps a surface, but as explained earlier (at least in my freshmans eyes), couldn't see how this rotation was going to happen with certainty of keeping this column perfectly at the same "height". It is very heavy, and since this weight is normally not "carried" in the vertical axis, I thought I needed to come up with another arrangement. I could be mistaken, of course.. amateur mistakes etc. but thought that instead I'd mesure from the rim of the hole to the ways, using the rim surface as a sub-reference. This needed not be absolutely flate/levelled and if I just made a note of the deviation in X- and Y- from this surface to the column ways, I could use this as a relative reference while scraping, ensuring that I didn't move from the original plane. In reality, the column ways were not far off, so it might not have mattered. Also, the head can be swung in both planes, so if the in/out movement of the column is just for positioning, ie. not in use while milling, well..
NB! My assumption was that the top of ways (not being worn) could be used to make the comparative X- and Y- measurements, and also that the spindle column was in fact square with the ways.

I am however tempted to make up some contraption so I can reference directly to the spindle column..
 
Last post today, I promise.

I carried on where I left this morning. Made some progress.. I hope!
Swopped to a couple of series with manual hip-scraping (for the try)
http://www.youtube.com/watch?v=RwYmFAiMZwM
(I know.. should have started at the the farther end, to avoid scraping over the chips..)
The blueing now seemingly has good bearing all over, so I altered technique, shortening the stroke trying to focus more on points than area
After 3 passes, I see I have gained some points, but also lost a little area contact at the lowest end. I have less blue on now than I had, so it can also be I was in fact being hasty determining I was ready for goint for bearing.. we'll see
http://www.youtube.com/watch?v=fl40JyHlvjQ
(I know.. excessive deburring..)
http://www.youtube.com/watch?v=DApDSF3QcBU
http://www.youtube.com/watch?v=6H2bVpRlVFY

( I chose videos again, because I seem to have an issue with images.. I guess I have exceeded my account, so need to adress this first)
 
Jan, The bluing looks like it is higher on the inside of the column ways . Remember you need to make yourself scrape the further away area as you will unconsciously scrape harder near to you. Unless its a dovetail and flat, as its a pain to scrape at the bottom of the doevetail unless your relieve it with a thin cut off wheel or a beveled edge of a carbide blade.

The bearing looks good, but lay a combination square on the ways at 45 deg and draw some pencil lines to your checker board looks more uniform. Remember to not stone to hard or to many times, all you want to do is remove the burr at the front edge of the scrape mark. You may want to make some sort of back ground color high lighter like my Yellow or we use to use red lead power to dull the shining metal so you can see the blue color better.

If you have a surface plate that will cover both ways at once you will get a truer idea the ways are on the same plane. If you do not have a plate, then turn your staright edhe at right angles and see how the angle of both side are to each other or plane from side to side. It might be parallel with the level sled, but may be off i--------i_______i--------i. I hope you understand. Rich
 
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Hi again folks,

I took the mentors advice, and did the X-check as well as spotting the 2 way sides as one flat surface (I called this local cross check).. dumb me, I knew about these test, but had forgotten.. maybe I got carried away doing the vids etc. but anyway.
As I don't have a big enough movable plate that can do both ways at an adequate length (but coming up..re-scraping an old 16x20" cast iron plate first), I also did a cross checkwith a 4" wide blueing bar, ie. in 4" increments (could have used the same long bar just cross-wise as this is 6", but it is ackward to handle this way). This of course only indicates over 4" inches, ie. a local check, but at least shows the left vs. the right way if they are in the same plane.
Hopefully I got the warning in time to avoid straying to far off, it seems like the results are a little inconclusive (at least for my untrained eyes).
Let's just say that this seemingly revealed that I have more scraping to do.. will however wait until I have the bigger(movable) plate so I get a better mark-up and decision base for further scraping.
http://www.youtube.com/watch?v=jcloENm2Y2Q&feature=youtu.be
(If youwant to skip the lengthy intro, spool to 1:50)
http://www.youtube.com/watch?v=lMcrX8KTUvo
The lower end, inside left way and outside right way, are not touching.
The X-check using the long granite plate slim side showed a more consistent mark-up, but not perfect
Last vid is just a glimpse into my cramped workshop. As told in the video, I am taking down the wall between the rooms shown, so I will be better off later
http://www.youtube.com/watch?v=6Zru4BcnKbI&feature=youtu.be
So next on the agenda is test & scrape the plate I will use for doing tests on the 2 column ways as one surface
I have a large granite table which should do as the reference
 
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