Kearney & Trecker Model 2H Horizontal Mill Rapid Traverse Clutch Repair

hello Keith Rucker here at finish machinery org so last week if you watch my odds and ends video you probably already got a little heads-up of what these projects about but last week when I was in the shop I decided that it was time to do some maintenance on the Kerner Trek II 2h horizontal milling machine something's been aggravating me for quite some time now has been the rapid traverse there's a slip clutch in the machine that on the rapid Traverse or if you were to hit something or coming into some resistance instead of it just keep on plowing through until it breaks something there's a slip clutch in there that will actually slip to keep that from happening and on my machine this slip clutch was just slipping all the time it was really just about any time you engaged in any of the three accesses even when everything's loose I could crank it by hand no problem at all no tension no resistance you know you the feeds work just fine but when you put it in rapid Traverse it was just you just hear this noise of it clicking and you know I've been kind of living with it for a while and I got tired of it and said now it's time to fix it so I started tearing into the mill and basically had to take all these parts off plus a whole bunch of other stuff and today we're going to put it all back together so I'm gonna zoom you in on this little slip clutch and kind of let you see what I was involved with it and tell you about some of the problems that we found and what we're going to do to hopefully hopefully resolve those problems so first off let's kind of give you a little orientation of what we're dealing with here so this pulley right here is basically the main drivers bells to go down to the motor and there's two bevel gears on this and these two bevel gears depending on one of them is going to turn all the time so it's directly keyed to this pulley so anytime the motors on it's constantly turning the other one on here only turns when the clutch is engaged it basically engages the spindle on the machine so and the reason there's two years here is one is for the rapid Traverse which can be used anytime the machine is on so anytime the machine is turning this is going to be turning and it will basically allow the rapid Traverse to run the second one powers the feed on the machine and it only is engaged when the spindle is engaged so just like you know anytime you're you would only want the table to be moving be feeding when the when the spindle is turned on and this whole assembly goes through this a big block that's laying down flat basically this spindle here is going to come up in these two gears here will engage these two gears and these two years here in turn basically what they're doing is there is in this or they're transferring the motion from horizontal to vertical so the horizontal here and then these two shafts are going to go down and we'll basically 90 degrees down and then it feeds into another set of gears actually these gears here that then go into the knee of the mill that actually powers everything so again you know one of these gears here is going to turn one of these spindles and the other one is going firm together one of them is always on which is the rapid traverse the other one is only on when the mill is engaged so I know this is kind of complicated and maybe you'll make a little more sense we start putting them back together but this is a slip clutch mechanism and it actually sits down right here and this gear here is going to mesh with this gear and again the idea is is that this thing gets going to bind that this gear will just slip but it's going to have enough torque in it or it's going to be pre-loaded enough that under normal operating conditions it's going to turn it just fine but if it gets in a bind it will slip so that's a look and see how that works so let's look at these parts of the slip clutch all taken apart so first off you got this up piece here and basically a plate it's got a bunch of little holes in the bottom they're actually radius to a 5/16 inch radius and there's a little ball bearing that fits down in each one of these little holes and a couple of comments here when I took this apart there's a we're marking here where these balls have been slipping and that's what they're designed to do there under spring pressure and basically that the spring pressure pushing down on this will allow it to to hold in those detents but when the pressure gets too much there's a spring above this that spring will push up and it will slide around over time we've got a little wear mark that's gone from one groove to the other and you know that really shouldn't be in there it's not that bad I was real concerned about it at first but after looking at a little bit closer and studying it I don't think that's the big issue and I will say that we found a couple of issues as we were taking this thing apart now it was very obvious to me as I was taking apart that someone had been into this machine before me and that you know you could you can see where you know screwdrivers had you know messed up screw heads and things like that where they really weren't doing a very careful job to fight honestly so when we got inside of this I noticed that the springs that were in here these are not the original these are replacements but they were about three different kinds of Springs that were in there some of them you could tell quite obvious were original to the machine some of them you could tell just were replacements the replacement Springs we're not near as strong as originals which was one problem and because it wasn't pushing enough pressure down on that ball bearing and it wasn't basically giving you the amount of is that there was it would require too little torque for this thing to slip I also got doing some measuring and I was measuring these ball bearings to see what size they were and I was kind of surprised that it was an oddball measurement it wasn't a nominal size and you know this machine that I'm working on I think was made in 1942 and you know us a machine made in 1942 really should not have any metric parts in it and I knew from the catalog that these were supposed to be 5/16 of an inch based on the parts manual and again I measured them that was a the size was didn't come out to a nominal size I was using a pair of digital calipers and I clicked the millimeter button and lo and behold they were 8 millimeter the ball bearings were which is about 20 thousandths of an inch larger than 5/16 so we had to thin she's going on number one these balls were not properly seating down inside of these they were a little bit large so they were not going quite as deep into that hole and second we didn't have the proper tension on each of the ball bearings so I took and and actually purchased some brand-new 5/16 inch ball bearings which were here I also took a 5/16 inch ball end mil and I just kind of cleaned up each of these holes so you know there was a overtime particularly those larger bearings that were in there you can tell that you know there was wear at the top of the holder wasn't he we're at the bottom the hole I didn't really make them any deeper but I did go around them and just kind of Peck them on just a little bit kind of clean them up and hopefully get some good sharp edges all the way around that and that might also help compensate a little bit for this little where this in here so we're going to go ahead and put the ball bearings in and show you how the rest of this goes together all right the next part goes on is the actual gear and if you look this gear has all these holes in here there's 18 ball bearings in here there's 18 holes drilled in here and it is gives enough clearance for those ball bearings and what happens is that ball bearing is actually riding inside of these holes so some people were asking me in some comments and stuff about how it tracks from one hole to the other where the ball bearing never actually leaves this chamber it's in there all the time so this is what's guiding it around and keeping it in that circle there is a little bronze bushing this in here and this is kind of tight going across the top once it gets on there it drops right down and this is the trickiest part of the whole thing is getting this bit in without knocking my ball bearings all over the place alright alright so now you can see this thing here turns around and those ball bearings are captured inside of these holes so let me all right that's down the next part here are the springs and again using the springs that were original to the machine and I could tell you could tell just by the age of the spring the quality of the spring you could tell which one's original so I took measurements of those original Springs as far as the diameter the inside diameter the gauge of the wire and the length and I was able to source some new Springs that had the same specs and actually was able to find them in the mcmaster-carr catalog online which worked out real well this is just a little of I don't think this is actually a dye spring here but it's very similar to a dye spring I think each one of these Springs according to the catalog gives about was it 16 17 pounds of pressure pushing down on it all right so again that's going to push that spring down these Springs will be compressed you know they're they're up a little bit high right now but they will be compressed and be under pressure the next thing that goes on is this piece here which is just simply a piece of clutch material and on top of that will go this metal disc and again this is going to give some more friction so again you know this this top metal piece is going to be it's keyed to this little stub axle but this clutch plate will actually slide up underneath this so as it's spinning this is a clutch material and it will hold it in place alright so the next challenge we've got is we've got to be able to press all this back together stuff taking the springs out temporarily here just to fit this on here and as you can see this little ring here is going to press down compress all the Rings and there's a retaining ring that will slip up underneath this little groove and again what I've got to do is I've got to get it all pressed down I got to get this retaining ring in now we've got this little champ for right around the edge of that and you let the retaining ring fits right around that chamfer so what I'm going to do is I'm going to go over on the lathe I'm gonna make a little tool to press this on and what I will do is I will machine a hole just big enough to slide around this outside ring and what it will do is they'll sit on top of this we'll take it on the press and we'll press down on top of this retaining ring and then that will then press everything down through here and the pressure will actually once the retaining ring gets on that groove it should snap right back down into it that's the plan so I'm going to make a little fixture over on the lathe now to press all this back together so we will start by just facing both sides of this and we'll punch an inch and three-eighths inch hole into one side it should slide right up over that Arbor down deeper than the rooves be good alright let's reassemble this one more time that goes on but this goes on the retaining ring will go on top of that and then you look we can push that down for the press and Al all snap in place let's see if we having luck all right we're over here the press now see what happens see I heard it click let's see if it snapped in now I don't think my wing is lined up just right looks like your trial and error all right Stan all the way I've been around here with my light looking at it and I think it's in the group so I'm going to carefully leave the tension on this see what happens it's not springing back up that's a good sign all right we're in the we got the ring on there that looks good all right guys looks like the clutch pack is all back together again and ready to go back on the machine so hopefully that will do the trick so let's go ahead and get this free assembled back on the part it came off of and try to put this machine back together all right so this gear is going to fit right down on a spinner right here there's a key way in there as a would repeat I pulled out the original Woodruff key and this thing is it's kind of chewed up it's been in there a while that's it's got some wear in it so I went and got my assortment of Woodruff keys and I've got a brand new Woodruff key ring up put in here and she was to go right on we got this all put back together now looks good last thing we need to do is as you can see this gear here is pretty much it's turning through here through this key but in the case where it slips this inner shaft will turn whereas or I guess this outer shaft will turn but the inner shaft will just slip so these there's a clip that goes in here to just keep those two shafts together and there we go that's that's good so this is all pretty much back together so again there's two gears that come out of the back off the main drive this one here is a turning the rapid Traverse gearing any time the machine is running this shaft will be turning whereas this gear here only turns when you engage the clutch on it on the machine so to two separate gear trains and then once for rapid Traverse and one is for the feed on the machine one other thing I'll note and I've already got a fix now but when I got in here this gear here was actually flipped over upside down which made it where it didn't align properly with the years coming off of the main drive this this gear here was engaging the other gear but only about an eighth of an inch of these two years for meshing so I realized that that was a problem and in the process of putting this back together I went ahead and flip that over so these gears should mesh up like they should now so this is ready to go back on the middle machine so let's uh let's get going all right guys I'm working in real tight corners over here so I'm not sure how well you guys are going to build to see everything going back together but I wanted to before I put this in here to kind of show you where it goes so that whole housing I'm going to use a pointer here because there's just kind of rooting for you get in here the whole housing that I'm working on kind of bolts in right here and this shaft through here will be where the main driver zone be belted up and down here and the gears will come in here and this is where they will all mesh together and then you'll have those two down rods that will come down through this mechanism here and these gears then go into the knees so basically we're transferring power you know from going in this direction to going down and then going across we're making to 90 degrees making it go from horizontal we're going 90 degrees down and then we're going 90 degrees off of that again perpendicular to this shaft and that's the basically the whole purpose of that whole a gear train that we're working on and again these drive the the two shafts here drive one drives the top one here drives the rapid traverse the bottom one drives the feed going into the knee alright we got it started so we've got the gear box all back in now next step is is a right here where these bevel gears are the power the horizontal power take-off we need to seal all those back up I've taken some time I've cleaned this I got a good and washed out with mineral spirits you know I want to make sure we got plenty of oil running in here so I'm going to take a minute here and just leave these up real good before we seal them up it looks like there's some probably some hole that's pumping in from the from the saddle part of the knee over here just lubricate these that still I'm going to get them to the loo while we while we're in here all right this block here now come in just like so and I'm just really holding it together all right so now we will put the big drive pulley back home and it goes in like such I want to lubricate these gears before I go in there that should be good they're going to mesh up on those gears on the backside there and before I get too deep into this I need to get this lined up all right it goes on there something like that I had to figure out which vaults go in here but see if here so there's five five bolts that put this on there we'll start smoking those up before I get too far in this something's not right all right so that's turning and that's turning my gear that will drive the rapid traverse if I were to turn this inner peace yep that's turning my feed so that's all good I don't know why that was seizing up let's try this again Oh what's going on I think it's hitting that bulb back there that's what it was it was just hitting when his bolts are sticking out too far and it was hitting in the back but that's turning great and that one's turning as well I'm tighten these down now all right so we've got the the main pulley back on here now is turning and as you can see when this pulley is turning all the time it's also turning a this drive shaft here which is the one that powers the rapid Traverse now there's also an inner hub that goes through there's another gear back there and this is what will power the actual spindle as well as the feed when it's engaged and this only engaged port from you when you physically engage the machine and to do that there's a little clutch mechanism in here so we got a little machined off surface here and a clutch pad fits on that and basically we're transferring to transfer from this gear right here to the clutch which will then have everything going throughout the machine so the first step will actually I've already got it sitting in here as a gear we need to bolt this in place I've got just kind of sitting up there right now that's not line let's get these uh six screws in here tightened in place all right next piece to go on is this inner gear and again it meshes with the outside there and there's a clutch lining on both sides of this that's going to pressure there's a you've got the inside pressure plate here and an outside pressure plate that will compress this in and I tighten this up from friction so this just fits right in there there we go it's like such and then we've got the outer pressure plate here and it needs to go next let me wipe this down so this clutch has an outer pressure plate here as you see and there are little holes in the back here that line up with these springs and there's two pins in here need to make sure this goes on so that all that is properly lined up and it's just a matter of feeling it and getting those springs and pins to all fit down in those little grooves just like such this little spider piece here is going to fit up a little bell shaped piece here in a minute that when you engage it it's going to basically cause these fingers to move out and when that happens it pushes the clutch plate up against this creates friction between all this and then drives the inner hub along with the outer hub it's all keyed together so you can adjust the tightness of this there's a little spring-loaded pin in here if you remember there was a little gear machine to the inside of that piece in there and basically what you can do is you can Index this around tightening it and loosing it into fitting this pin into any one of those pieces and that allows you to tighten this clutch up in operation so if you've got one of these Mills and you know the clutch is slipping it's a fairly easy fix you just come in here and tighten it up presto you're done so you can fine-tune this once you kind of get the machine in place I'm going to leave it a little bit loose right now because it gives me the ability to get the next piece on of a little bell shaped piece and they will tighten it up once it's on there but before we do there's another little washer that goes here and then there's a nut that's going to come in here and kind of tighten up against that you know this nut doesn't stay tight all the time because you do have a little bit of adjustment in there to tighten this clutch up but we want to go ahead and snug it up in place where it's at right now so let's get that going here but that tightened up and again this is a basically just to keep this from coming out too far because you still have some adjustment in here but this little Bell piece is what's actually going to tighten up the fingers and again I got it a little bit on the loose side right now because I've got to be able to get this on some going - there we go we've got that on there now and now I'm going to pull the pin out and we're going to tighten the clutch up a couple of washers going here and then there's this castle nut that has a cotter pin in it to keep it tight all right so let's show you how this works so again in normal operation just the outside wheels turning just the one shaft over there is turning now I'm going to engage the clutch which pushes this bailout tightens the clutch up now everything is turning but the Internet our staffs returning and if you look down here both the feed and the rapid Traverse rods are turning so this is working again we may have to fine-tune this clutch once we get it running but for now I need to put a cotter pin in here and put the belt back on and I think we're ready to test this thing out we got it up and running I've been messing around this thing for a few minutes I thought I'd give you guys an update as to where we are with this repair and whether the success/failure whatever you want to call it so just to back up and let you know where we were starting from when I got started on this mill the rapid traverse punch was slipping in all three accesses so you know my X my Y Emma's the up and down and coming here and playing with it you know on the table everything looks real good in now not a problem we do have a little bit of problem on the V axis and here we're still getting some slippin I can tell you guys that I've made a tremendous improvement in the machine but I'm really not 100 cent satisfied with it I was really wanting this z axis to work you know going down is no problem because we got gravity working in our favor but coming up just slipping like crazy so you know now I guess what am I going to do well for now we're going to just use the mill now that I've been into it and you know before I got started I really wasn't exactly sure what all that grinding noise was and I was really concerned that I had some gears that were stripping out now that I know that it's a slip clutch that's what it's designed to do and it's doing what it's designed to do although not as effectively as it should be I know I'm really not hurting the mill I'm not helping any but I'm not really not hurting it any and I can know that for lifting up on the z-axis you know you can always go back to the good old fashioned do it by hand method and that is probably what I'm going to do for now I will come in and say that when I was looking at options you know at first I was thinking of replacing that part to have a little defense that were worn in it and I'm still not 100% sure that that may not fix the problem but I did some inquiring and I found the company out in California actually has that particular part new old stock sitting on the shelf a problem he wants about $600 for it which is a lot more money than I really want to spend I think I've paid $800 for the whole milling machine and just think that much money into one part this makes me cringe I could make the part I don't know that that would fix the problem though you know maybe if I could find some heavier Springs I the springs that I put in there are from all I can tell very comfortable to the ones that were original to the machine but you know they're not a perfect match and I've got the strongest ones I could find in that size on the mcmaster-carr website so I may need to look and see if maybe I can find even some heavier Springs somewhere else now that I know how to tear in the machine it won't take me years long next time another option the same company out in California that has the replacement part also told me they've got a fixture set up where they can basically rebuild that clutch pack put new Springs in it for me and get it calibrated to the factory specifications which I'm not sure even sure what they were as far as toured they got a fixture that they can test it on they want to thank 450 dollars to do that again more than I really wanted to put into it but it's an option so for now we're just going to use the machine at some point in time we may try to see about doing something else to solve this problem I don't know yet we'll just have to see ultimately I think I'd really like a bigger milling machine anyway so I'm not sure I really want to think a lot more money into this one so anyway that's where we are we're going to call it a partial success may be mostly success I'm definitely better off than where I was but still not 100% satisfied with so thank you guys for watching we'll talk to you later you

Channel: Keith Rucker - VintageMachinery.org

Views: 145,911

Keywords: Machine Shop, Machinist, Horizontal Mill, Kearney & Trecker, Clutch, Restoration, Vintage Machinery, mrpete222, Mr. Pete, Tublican, Keith Fenner, Turn wright, Adam Booth, Abom79, Tom Lipton, Ox Tools, oxtoolco, myfordboy, Jody Collier, weldingtipsandtricks, Welding Tips and Tricks

Id: lT_g8lPi-Zs

Length: 43min 9sec (2589 seconds)

Published: Fri Jun 19 2015