Rebuilding a Schaublin 102 compound slide - Part 1

[Music] hey welcome back today we have a Shaolin 102 compound slide on the healing bench this is the compound slide of a relatively well made I should say brilliantly well made mid-sized instrument make of leaf Sharleen Swiss company of course still around still making small instrument make of leaves and CNC lathes and this doesn't belong to me obviously because I do not own a Shaolin this is a customer part or piece so why this here it's worn and it has another issue that I will go into problem with most slices is that they wear uneven in this case as you can see I can crank it nicely along it's almost a bit too loose but when I get to to the other end of the travel here it binds up that means that the dovetail down here on this end is worn it's narrower than over here and we will measure that of course so what this series of videos will be about this will be a complete rebuild of this compound slide starting by taking measurements deciding where to scrape do the scraping fit the new gear this is a tapered tip newly supplied from chablis but it's not matched you have to match it yourself so we'll do that too and we'll get everything done and do the check final check after we're done too have no I I hope this will be a very comprehensive series of videos on this topic so first we have to take this guy apart of course because otherwise we can not do very much [Music] over here we have a screw which seems okay this holds the bushing the end pushing for the spindle this is actually a very nice design this is a Acme screw in here and it's it has a main bearing over here with as far as I can tell two angular contact bearings over here and it's also a bushing over here so the spindle is nice and rigid in there we do not want to miss the screw up so we will look for a screw driver that's a very good fit otherwise it will shatter up the screw that's not an option of a customer part people don't like if you ruin their screws same F if you have to pry or level something use brass or copper now for example a small brass pry bar that I can use to get stuff like this and bushing out I'm not sure yet how all this comes apart these screws for sure hold the nut in place okay now we should be able to pull out the give and with the get out of the way we can take off the lower part of the compound here yes that's actually where a common design for a tapered give a gesture a screw with a with a ground collar and there is a slot in the tapered give virtus or the color of the screw engages there's a very tight fit there is no axial movement off to give on the screw and now you can also see that that one off to two Gibbs a little bit longer cause this one has a broken end and we can pull off this lower slide first glance it doesn't look too bad but I can see somewhere here this side there comes the spindle assembly now I just have to unscrew the nut never have it all apart I'm not going to mess with the but the bearing setup here I think this is good good adds it is I will check it when I get it all back together but for now I guess we don't have to do anything to it also this nut feels very tight still apart from that a little bit of axial plane then that doesn't kill anybody your work in an approach direction anyway on the leaf so backlash is not a terrible issue and Trust in fact not this cast iron being a Swiss machine I would have guessed that this would be bronze okay there we go that's the one shoveling one or two slide taken apart so now it's time to look at the individual parts this is the lower side of the compound which bolts to the cross slide off the shovel life yeah these two holes I guess with bolts and the t-slot and I marked the area I took mine I took some stems and I very carefully cleaned and stilled the whole surface and as you can see around this mounting hole we have two highly polished areas that's very the mounting bolt at once this cross light pulled some materials through while it's mounted on the lathe that's not a problem because it's riding in this circular t-slot and around the scrool there is clearance of course but when we get to a surface plate now we want these high spots to be stoned off flat to the rest of the surface otherwise this will mess up our measurements because it's like having a pivot point where it can tip over all so we have to stone to really clean and stone these very careful before the dosa surface we can't do any actual real measurements or cleanable of alcohol those precision long stone and we can really go we cannot go too far with these stones because it just stopped cutting not the beauty of the precision ground stones with enormous stones you would have the ultra careful not to alter the surface as you can see there are no scratches from the stoning there are still the original grinding it looks like Blanchard ground with a couple wheel ok I put it on the surface plate and I took a one hundredths of a millimeter point a one millimeter that s indicator and I mapped out the parallelism of these surfaces these are the flat part of the bath tale this is worthy the compound slide rides on and as you can see we have I just I just take one area as zero like here this is my zero and for from there out I mapped the remaining surface out plus or minus obviously to the end of the travel or to the end of the surface it's worn it's minus 2 minus 3 minus 2 minus 1 so it's actually the surface has is like this it has a hill in the middle and it's dropping on the ends which is very common very common of where you will not relax we will basically never see the short part of a dovetail slide being worn in the center of it it's basically not happening and this side over here actually is a little bit higher this is plus two does plus three compared to this but it's also dropping to the end of the surface so just been looking at this this is easy these two surfaces we can just surface grind perfectly parallel to the bottom surface and then just scrape it for bearing we do not have to do any geometry straightening on these two surfaces which is nice because it's fast okay the other part of the slide this is the longer part so now surface the first thing I check is if it hinges properly that will tell me if it's rocking on the surface plate or doing anything stupid that messes with my measurements the hinging is simple you just take one end and you try to spin it and you you try to identify the point around which it rotates or hinges and if it's about 1/3 of the total length to the inside it can be pretty sure that the part is relatively flat same on this side yeah this looks good I will later blew this up but it it feels very good you can also take a plastic hammer and listen if it makes a rattling noise when you hit it you know that I'm sitting hollow somewhere but this sounds very solid okay I checked the wear on this one too and out here on the end it's it's zero there is also the original grinding marks off of Chablis to be seen so I can take this as my cero and this can see it goes down on this side minus two and then back up to zero that means it's exactly the opposite of the further part it's born in the middle and our channel on the ends which is also a common mode of where for the longer part same on this side this is heavier warm Sarah zero minus four minus six and it goes back to three this is also hollow in the center and a little bit low on this end but basically both sides born in the center mostly so already we know a little bit of about the part and this helps us to decide what we're going to do I already know what to do well the dovetail slide it makes sense first to scrape the flat part flat and parallel to whatever you wanted to be parallel in this case you drop your pen and then you scrape it to the top side of the slide because when you move your slug you do not want to have this this surface here change its height because it's not changed the center height of the tool you have put on it like that turning to that would be quite annoying then we scrape the the dovetail parallel that means we scrape one side parallel for example to one of the T slots worked outside I have to check which is accurate then we script the second side parallel to the first one and we take the lower part we scrape the flat part or this case with a surface find a flat part and just scrape it for bearing and match fit one side of the dovetail to the put a longer slide we use this as a master for this and then we have to fit the give into it okay I just blew the straight edge I'm going to use for the for the compound slide up at this a few days ago and I just wanted to see if it moved because this is just continuous cast cast iron just like durable and it has not stress relief by having you send out to a heat treat or that to be a bit careful and watch and monitor it if it moves but I rang it a few times hanging up and did it with a mallet during straightening and it didn't move very much I guess or hope that it's relatively stable I measured the width of the dovetail by using tins and the micrometer to check the width over the world over a length and it's about 0.15 millimeters of wear from end to end which is quite substantial I would not have suspected that much wear but it is like this we have to deal with it but the measurement of the width of the dovetail is not reliable until these surfaces here are flat otherwise you introduce two errors at one time so first thing we're going to do this we're scraping the flat part of the long slide of the long part of the slide these surfaces on both sides flat parallel to the top and preferable to the same height it's not absolutely critical that these two surfaces are at the same height to the top surface but it makes life a bit easier at least in my mind what to do the scraping it's hard to do this with the by overpower scraper because you always hit the end of the dovetail with the scraper but I have to do this by hand and I meet it cut me a second set of wooden v blocks on bandsaw I was just threaded wood and this allows me to rest the slide earth securely and clamp it with the large wooden clamp here so this is a very stable setup the only thing that's going to move this the table on I'm working on and now I can rough up the surface here and I already can can use my numbers here for very rough roughing I will scuff up the whole surface or break up the whole set so I can take a bluing but I will hit the ends I will hit this end here and this end here heavier or at least twice as often as the center the center is the lowest point minus 6 and minus 5 and there are point O 5 millimeters height difference between the end and here so we already can bring this down without very much measurement we also have to be very careful down here is a ridge it's borne up to here and behind it there is unborn surface because that's very tapered Gipp slides and the tapered tip only touches the angled part of the dovetail not a flat part of the dovetail brought the camera in a little bit closer I hope you can see this rich back here about here there should be a shadow line of visible on camera I just realized when I move the camera or hunt the way I look at it it's easier for you to see here is the edge behind here its unborn and here it's all war I have to take this knife edge stone and grind a heavy chamfer on the edge here so it doesn't bind up the relief - yes just pretty handing it against the bottom wheel okay now I'm loosening up the clamp so this part sits freely in there and it's not distorted by the clamping pressure then I take my blue dub straightedge place it in the dovetail making the lower edge of the triangle hit first and then tipping it in like this then I move it back and forth to rub the surface so still what I expect it's hitting the heart down here hitting hard here hitting relatively hard here and here Center is relatively clear we still have a little bit of contact here on the ridge so we will heavily rough down all these areas this this this this and center here is or nothing to touch this we will take this home pass before we get carried away with goes to a surface plate and take a few measurements so we do not do anything stupid there and as you can see I take really heavy cups retinol I'm making real chips not dust and now we hit the rich down there again because it's still a little bit high and cleaning it using some alcohol because I have alder the scribbling of mine over there okay I took another bluing after the last scraping past in itself and we get somewhat of a contact over the whole length but now we have to check so just the scenario surface here does not get tipped in or out like this it's not super critical because we will match fit the other part to this one but there's easier if it's parallel in my mind it's easier to keep stuff parallel and flat and rectangular than to match fit everything makes it easier to measure of truth it's easier to measure twist in this part or the surface when it's parallel on an angle I think it's really hard I mapped the surface out with dial indicator I'll test indicator on the gauge block the gauge block is there to spend the holes of my scraping especially as the scrapings right now super super rough if you're running indicator along it you get you get seasick for each position I have two numbers this one is always out to the edge and the upper number is inside here at the inner end of the dovetail so we start over here at 0 and we drop by five hundreds of a millimeter down which is okay it's not terrible bad especially as it's a very even drop they're not going up and down like crazy it's already kind of straight so little steps great bit kind of step straight but we'll hit we'll divide it into a few like this one time two times three four and I was here five times just without measurement in between just to drop it down okay step scraping Brooks this way we start out here and square that one time scrape will scrape the whole surface then we will start over in this square leave this one on touch scrape everything then we start here three times scrap everything start here scrape everything and then scrape the last one a fifth time that way we will bring the whole surface progressively down tipping it down we will imagine this light line here acting like a hinge we just move down the whole surface [Laughter] [Music] okay now we flip directions and go that way starting in the second square second square down now we change to the third one and change direction again change direction again and one last time for their last square there we go now we clean it donut and see what we have generally step scraping is a good way to remove all bunch of material relatively short time and the chances of messing up are relatively low okay we've only this one scraping pass we'll get it down to from zero to minus three hundreds so it's almost double as good as four which is good what we also can do we can compare it to this side now and this side this roughly yeah mr. fumble finger [Music] three hundreds of a millimeter higher than over here in this war an area on the end it's more yeah it's five hundreds of them only over here so the surface is in general lower than this which is good because we can just move this down later okay added some more work to the surface and as you can see or hopefully can see in the camera I'm Way beyond the roughing face this is almost going into finishing scraping I got a bearing over the whole surface maybe ten to fifty points per square inch and it's also parallel very parallel to top surface so for now I will leave the surface alone and that will draw my attention to this side and it'll bring it down to be level with this side then burr on a very good road once we have those two surfaces we can measure the parallelism with the pins okay I measured the first site that I scraped then that's zero to zero from end to end and it's about five microns tilted to the inside so it's I can fix that during finished scraping but it wouldn't matter too much because it's five five six microns really not that much but right now I'm measuring the other side that needs to be scraped now and it's 0.072 0.08 millimeters higher than this side which is good because I can take it down now and we will have a problem if the surface was lower because then we would have to scrape this flat and then we would have to bring the surface that we already scraped bring it down to so doubled of Arc so be careful where we start to scrape and that's before just using gauge block my interrupted test indicator to compare the side-to-side what I'm going to do is I'm again step scraping I'm going to hit the center here two times one time this time this direction one and this direction just stuff it up and these other areas here three or four times I think four times not to that's that's okay because we have to remove a lot of material anyway seven hundredths of a millimeter we can go pretty crazy on this but while roughing you have to be a bit careful not to knock the surface completely out of alignment otherwise you create a lot of extra work and who likes that too extrovert that's not necessary me me not well I'm going to hit the hole so face two times now then the ends two times extra okay a lot happened since the last scene I completely completely I scraped these two surfaces here the parallel surfaces I semi finished them they they still need work they have they have even bearing but it's not very nice and they are within tolerance all within way less than one hundredth of a millimeter and yeah I considered those reference surfaces now for for a moment and I took the base which was worn on the ends and high in the middle and a surface from the top just to get the major of material and it's indicating now zero zero zero zero because my grinder grinds pretty straight since I recreate the table and yeah that's already a major hurdle because I just have to scrape this for bearing now but that flater I just grunted to have it off the table and now it's time to do the dovetail I will start with one of the duffed hills and align it with the side with one of the sides of the of this cross slide across that I already checked it it's nice and parallel ground and the T slots are also perfectly lined with the outer dimensions of this of the top slide so I can use I very carefully still decide here which has a lot of big marks somebody used obviously something like a Chuck key or or something else hard to knock it into alignment for adjusting you see that Austin an old used lace some people are a bit I hope it's not the Johanna that is using the machine now that happened that who did that please don't you steal on cast iron to get stuff aligned yeah so now the task is to font to take one off to two dovetails and scrape it parallel through everything else and to measure that just take a I'll pick Bella pants are a bit dangerous almost they're generally not perfectly round and not perfectly straight so I had cut me some carbide ROM stock although in mill shanks down and I use those just for just for peace of mind so and the trick now is there is no trick we just drop the pin in the dovetail we find top dead center by sweeping the indicator across the pin like this this is top that Center almost and I really like to interact with indicator it's it's incredible sensitive forum for 1/100 of a millimeter indicator not a problem to see $5,000 million on this guy and then we indicate the other side and it's 500 700 me the low so minus 5 all my numbers at the moment are in one hundredths of a millimeter increments 0.01 so the money said there are no fractions in metric and of course they are you have 1/10 of a minute you have one hundredth of moving it and you have one thousandth of a millimeter and so on and so on but they are all based ten ten hundred thousand and so long not sixteen thirty seconds 64 so there are fractions so yeah that's minus five here - so I'm mapping out the the where of this one dovetail now it's minus four minus four this is the front end so it's more worn on this side than on this side and here we are already at minus two and here it's zero and out here is also zero so we go from zero to minus five hundredths of a moment that's not too bad I probably can step scrape doesn't one or two passes pretty close okay I already did some scraping to the left tail surfaces to the angle surfaces and there are two ways how you can measure there are more ways obviously but I have two ways of measuring I can either take this thing drop everything yeah that was carbide okay once you have dropped everything successfully you can take two pins in this case again the car back pins and just Mike over it and look for the largest spy mention takes a bit of practice and a bit of feel how are you manipulate the micrometer and find the high spot to get the rights drag when you sweep over the pin but it works very good but there is another way which I probably like more you need an angle plate or box parallel a bunch of parallels normal size and two additional pins preferable ones that you do not draw all the time and you but the pins into the angle dovetail let the pins rest on the parallel parallel sits obviously on the surface plate and the part itself backed up against the box parallel here so it's nice and square to the world and now we can just drop in a pin and we can very easily sweep top that center of the pin of the diameter of the pin with the indicator in the surface gauge and map the dovetail that way which I find it's a bit more setup but it's I think it's it's more precise [Music]

Channel: Stefan Gotteswinter

Views: 62,450

Rating: 4.953064 out of 5

Keywords: scraping, handscraping, biax, renz, schaben, flachschaben, handschaber, rebuilding, magnetic chuck, schaublin, schaublin 102

Id: -BYt3GHBuNk

Length: 39min 2sec (2342 seconds)

Published: Sun Jan 28 2018