What's new
What's new

Van Norman 1R3 bogs down then shuts down at higher RPM gears?

kd1yt

Cast Iron
Joined
Dec 6, 2013
Location
Vermont, USA
After some sidetracks of other parts of life, I finished putting a new cord on the Van Norman 1R3 that I acquired a month and a half ago (had brittle insulation in the old cord that was on it), and hooked it up to my 7.5 hp RPC.

The machine is generally all original and very clean. It has tags showing that it was a US gov't machine and then a vo-tech school machine. Doesn't look like it had hard treatment in either.

Runs nicely except for the following strange behavior- in the highest RPM gearbox settings, the spindle turns in a slow and labored way (instead of at the expected high speed) and then in a short bit (I didn't watch time but I would say under 10 seconds) the protectors snap off and it shuts down. This happens all of the time in D-4 (1325 RPM) and D-3 (2000 RPM), and some of the time in C-3 (1150 RPM). All speeds/ gears below that seem to run normally. I noticed also that it seems like the "N" between "C" and "D" is an "un-find-able neutral"- the neutral spot/ locator hole/ marking is there but there is no apparent way to actually get the gearing in neutral- if turned gently by hand while shifting, as soon as it's out of C it is engaged in D, with no neutral/slack in between).

When I bought the 1R3, the seller started it up for me; he mentioned that it did not seem to be able to attain full RPM in the highest gears, which he attributed to trying to start/run the 3hp 1R3 on his 2hp RPC [which seemed credible, and I believe that he was sincere). Since I am running a 7.5hp RPC I don't think my RPC is a bottleneck. I am running things through a 10AWG drop to my shop, which I know is not ideal for large loads, but then again, the shop lights do not dim or flicker when starting the VN, which makes me think that voltage sag is not part of what is going on.

Since bringing it home I replaced the side timing belt drive belts- the ones on the machine had not failed but had signs of deterioration. The drive motor spun freely. The gearbox seems to spin freely without any binding or clashing that I can detect.

The lube in the sight window in the ram is moderately cloudy, and when the machine is run, it gets very foamy, and then even after the machine is stopped, looks sort of milky. I should and will drain and put in fresh lube (first order of business). I am debating whether to do some kind of intermediary 'flush' following the drain out of the old lube and the addition of the new lube and appreciate any suggestions on whether the flush is or is not a good idea, and if it is a good idea, suggestions on what to use to perform the flush. Wishful thinking is that fresh lube could make it run normally, but I don't want to pin my hopes on that- seems implausible that even crummy oil could create that much drag at higher RPMs.

This is my first Van Norman, and I welcome any suggestions from other more experienced VN owners whether there are any known phenomenon in the ram's gear train that could be causing this, or, even if you don't know of any known phenomena that could cause this, any suggestions on systematic ways to begin to troubleshoot & solve/ mitigate. The 1R3 has what I'd call 'clockface' shifting arms, whereas the older machines seem to have different shifting arms, but I would think that VN probably didn't change the core of the gear train a whole lot.

Thanks in advance; I am extremely impressed with everything about this 1R3 and am eager to get it running well at all speeds.
 
Sounds like maybe the wrong weight oils in the gearbox and/or cutterhead. Another possibility is that it the motors are wired for 440 and running on 220. Mine comes up to speed at 2000rpm so quickly that it is frightening, and that's on a 5hp phase converter.
 
Runs nicely except for the following strange behavior- in the highest RPM gearbox settings, the spindle turns in a slow and labored way (instead of at the expected high speed) and then in a short bit (I didn't watch time but I would say under 10 seconds) the protectors snap off and it shuts down. This happens all of the time in D-4 (1325 RPM) and D-3 (2000 RPM), and some of the time in C-3 (1150 RPM). All speeds/ gears below that seem to run normally. I noticed also that it seems like the "N" between "C" and "D" is an "un-find-able neutral"- the neutral spot/ locator hole/ marking is there but there is no apparent way to actually get the gearing in neutral- if turned gently by hand while shifting, as soon as it's out of C it is engaged in D, with no neutral/slack in between).

When I bought the 1R3, the seller started it up for me; he mentioned that it did not seem to be able to attain full RPM in the highest gears, which he attributed to trying to start/run the 3hp 1R3 on his 2hp RPC [which seemed credible, and I believe that he was sincere). Since I am running a 7.5hp RPC I don't think my RPC is a bottleneck. I am running things through a 10AWG drop to my shop, which I know is not ideal for large loads, but then again, the shop lights do not dim or flicker when starting the VN, which makes me think that voltage sag is not part of what is going on.

I'd say Mike put forth the most likely cause, a motor wired for 460v but running on 230v. But, I'll list my experience in this area even though I don't think it's the cause of your high-speed startup difficulties. Hopefully it may help you figure out how to fix the neutral position.

When going over my 1R3 I noticed that position 'D' worked, but the selector didn't physically move far enough to engage the locking pin in the hole. I suspiciously noted :scratchchin: that the selector moved far past the 'A' position. Reviewing the parts diagrams (attached below), I familiarized myself with the way the selectors work and theorized the selector arm was off by one or two gear teeth. Turns out I was right, and even worse than not locking into position 'D', the offset meant that for all other positions, the gears were not fully engaged (only half width or so). I was able to fix it by loosening the setscrew and sliding the gears out of mesh, rotating and sliding them back into mesh. It sounds easy but I messed up and managed to get BOTH selector arms out of mesh and out of position! :crazy: I was able to put it right by sliding the moving gears all the way to one side, positioning the selector appropriately and putting the gears back into mesh. Once it's done, double check your work by making sure the selector arms move the same amount past each end position, and also put it into gear where the gears can be seen from the top and make certain the gears have full width engagement.

1R3 Ram Transmission.jpg
1R3 Ram Transmission Shifter.jpg

Since bringing it home I replaced the side timing belt drive belts- the ones on the machine had not failed but had signs of deterioration.

Interesting - I see the timing belt drive in the parts diagrams, but mine has four vee belts. The belts which came on the machine look very old, and they're somewhat loose - they are link belts, each link riveted together.

0707172342_HDR.jpg

Problem is, there are no idler pulleys and the wrap on the motor pulley could be better for such a small pulley. I was having strange problems with the machine bogging down (as heard by ear) under moderate load, and once I put a tach on it (I have a cheap laser tach - highly recommended and worth every cent!), I was able to see the machine wasn't even getting up to speed in the top gears! Using the tach, I was able to find that the motor was fully up to speed but the belts were slipping at high RPM even under no load. So, replacement belts are in order and I may need to add idlers or even replace the pulleys and go to a poly-vee style belt if I have any trouble with the replacements.

The lube in the sight window in the ram is moderately cloudy, and when the machine is run, it gets very foamy, and then even after the machine is stopped, looks sort of milky. I should and will drain and put in fresh lube (first order of business). I am debating whether to do some kind of intermediary 'flush' following the drain out of the old lube and the addition of the new lube and appreciate any suggestions on whether the flush is or is not a good idea, and if it is a good idea, suggestions on what to use to perform the flush. Wishful thinking is that fresh lube could make it run normally, but I don't want to pin my hopes on that- seems implausible that even crummy oil could create that much drag at higher RPMs.

I highly recommend changing all the fluids before you run it much more. Oil is cheap - after mis-remembering the recommended viscosity and mail ordering a $97 (incl. shipping) 5 gallon pail of Mobil DTE 26 (ISO 68), I gave up on expensive, not-locally-available Mobil products and went with ISO32AW hydraulic oil from my local Advance Auto, which cost less than $50 for 5 gallons.

For what it's worth, the VN manuals recommend flushing with kerosene, which I've also read is standard practice for other machine tools. The oils in my 1R3 looked clear and in good shape so I just did a drain and refill (though sometimes twice now as I've gone back to work on various gearboxes). With your oil being milky or cloudy, it may be contaminated with water or something else; I'd say a kerosene flush is a good idea.

Ben
 
Thank you both VERY much. I'll have to check about the motor wiring: the seller had used it and I wouldn't have assumed that it would run acceptably at all if the motor was running on 1/2 voltage- but I suppose that the odds are that the prior owner wasn't really working at the envelope of what the machine would be capable of at full steam. In doing some basic inspections I have previously opened the side door, and also opened the motor cover on the left side of the ram; I wasn't specifically looking for windings connections for voltage changes, but also don't recall, so now I will look with that in mind. I will definitely be giving the machine new fluids.

Ben- can you please tell me how you arrived at the ISO32 viscosity? The only reference I can find in the manual says "300 S.U.V. at 100F" which from some information I have found, looks like the lower edge of ISO68 Viscosity Charts - Bob is the Oil Guy I am not aiming to be disagreeable, just want to know your reasoning. I have unheated workspace in a northern climate so maybe I should just aim for ISO46.

Also- Ben, thank you for describing your findings and corrective actions on the gearing and shifters- were you able to access the setscrews, and observe the gears, through opening the uppermost thin sheet metal plate cover, or did you have to lift off the upper housing that the shifters are housed in?

Thanks!
 
In doing some basic inspections I have previously opened the side door, and also opened the motor cover on the left side of the ram; I wasn't specifically looking for windings connections for voltage changes, but also don't recall, so now I will look with that in mind.

The motor winding to line power connections are made in the electrical box closest to the motor pulley. Not the one on top - that's just used to connect or disconnect the pendant control - but the one towards the back corner of the machine.

Ben- can you please tell me how you arrived at the ISO32 viscosity? The only reference I can find in the manual says "300 S.U.V. at 100F" which from some information I have found, looks like the lower edge of ISO68 Viscosity Charts - Bob is the Oil Guy I am not aiming to be disagreeable, just want to know your reasoning. I have unheated workspace in a northern climate so maybe I should just aim for ISO46.

You're correct about the equivalent viscosity of 300 S.U.V @ 100*F - it seems our manuals are different! Mine recommends 150 S.U.V @ 100*F oil; you can see it posted here: http://www.practicalmachinist.com/v...n-1r3-1rq3-manual-parts-list-diagrams-339773/

Can you scan and post your manual, in the highest quality you can manage? I'm curious to know if there are any other differences.

Also- Ben, thank you for describing your findings and corrective actions on the gearing and shifters- were you able to access the setscrews, and observe the gears, through opening the uppermost thin sheet metal plate cover, or did you have to lift off the upper housing that the shifters are housed in?

Thanks!

Welcome, glad I can help. I only took off the uppermost thin cover; you can get at the setscrew that way, and though observing the gear mesh is a bit challenging, it can be done. Judging from the parts diagram, if you remove the larger (and really thick) top cover, you'll be removing the entire shifter mechanism! It may be easier to work on it that way, but I think you'd run into difficulties getting it back on with all the gears in the right positions.

Ben
 
Many thanks Ben! On the lubricant, I am scratching my head as to how we are coming up with different references, because I am going by the info I found in the high quality scan that you posted in your recent thread, and that has the 'RPI' mark on the bottom of the front cover. I am looking at page 9, top upper left, second paragraph, where it seems to reference the 300 S.U.V.- and so I am curious what other place in the manual references the different/thinner viscosity?

By the way, as to your funky belt arrangement, what is interesting to me is that even though the manual (page 27) shows an arrangement where a poly-vee belt is tensioned by a pair of upper/lower idlers, on my machine the toothed timing belts are tensioned by nothing other than the precise fit of the belt to the big and small pulleys. It's beginning to look like the belt drive had at least three variants. I'll have to look at the serial# on my machine and cross the # to the date charts. Interesting that such a limited production machine seemingly had all of its especially complex and robust main assemblies remain the same, but then something as simple as the belt went through at least 3 variations!
 
Many thanks Ben! On the lubricant, I am scratching my head as to how we are coming up with different references, because I am going by the info I found in the high quality scan that you posted in your recent thread, and that has the 'RPI' mark on the bottom of the front cover. I am looking at page 9, top upper left, second paragraph, where it seems to reference the 300 S.U.V.- and so I am curious what other place in the manual references the different/thinner viscosity

No worries, it's easy to miss. On the bottom of page 9, there are lubricant charts for the different variants which for the 1R3 specify 150 S.U.V @ 100*F for items marked 'B' (feed and ram transmissions), 'C' (various manual oiling points) and 'G' (cutterhead gears). The text you reference at the top of the page has the vague warning "unless otherwise specified" - you'd think they could have made a reference to the lubrication chart! :)

I made the same mistake, which is how I ended up with $100 of Mobil 26 I couldn't use :)

By the way, as to your funky belt arrangement, what is interesting to me is that even though the manual (page 27) shows an arrangement where a poly-vee belt is tensioned by a pair of upper/lower idlers, on my machine the toothed timing belts are tensioned by nothing other than the precise fit of the belt to the big and small pulleys. It's beginning to look like the belt drive had at least three variants. I'll have to look at the serial# on my machine and cross the # to the date charts. Interesting that such a limited production machine seemingly had all of its especially complex and robust main assemblies remain the same, but then something as simple as the belt went through at least 3 variations!

Tomorrow I'll pull my serial number and we can compare when our machines were produced. I agree it is odd...3HP just isn't much power to transmit, I wonder why the multiple revisions.
 
The serial number on mine is 6103-363, which seems to indicate it was built in late 1963. Pretty early in the run - perhaps the 93rd of 452 machines built.
 
...
I highly recommend changing all the fluids before you run it much more. Oil is cheap - after mis-remembering the recommended viscosity and mail ordering a $97 (incl. shipping) 5 gallon pail of Mobil DTE 26 (ISO 68), I gave up on expensive, not-locally-available Mobil products and went with ISO32AW hydraulic oil from my local Advance Auto, which cost less than $50 for 5 gallons.
...
And I highly recommend that you DO NOT use hydraulic oil, such as Mobile DTE 26, in your gearbox. You wouldn't put hydraulic oil in the transmission of your truck, would you? McMaster-Carr has the correct oil, Mobile DTE Heavy-Medium (ISO 68), in 1 gallon jugs for $27.15 plus shipping: https://www.mcmaster.com/#2158K15

The reason that OP has milky, foamy oil is probably because the existing oil does not have a good anti-foaming additive.

Cal
 
Thanks Ben- it took me enlarging the diagram of lubrication points to be able to see that it had a "B" for the S.U.V. 150 pointing to the top cover of the ram- and then only after even more study to see that the "G" pointing to the cutterhead also specifies the 150. Thank you, were it not for you I would have missed this. I am left wondering what - if anything - the default of 300 S.U.V. in the text at the top of Page 9 actually applies to? Hope to open the cover on the motor wiring connection box and at least take a first look later this evening. Thanks again to all for all of the excellent input.
VN 1R3 lube chart.jpg
 
There is a possibility the machine was originally wired for 480V. The machine was switched at a later date to 240V, but the heaters in the magnetic starter weren't changed. The heaters (overloads) need to be changed when the motor voltage is changed. The heaters don't care what voltage they see, they trip at rated amperage whether operating on 120 or 600v.
 
Yes, improperly matched heaters and motor voltage are going to produce pretty much the same issue. If the motor has been rewired for low voltage and the heaters haven't been changed, they will see the double amp draw and shut down very quickly, but I'd expect that, even running at low speeds.

If the motor is wired for high voltage, but running on low voltage, the motor power will be about 1/4 what it should be. It will have very little torque, so it may start and run at lower speeds, but will certainly kick out the heaters at higher speeds when the torque can't get over the hump to get the geartrain sped up and it starts drawing very high amps.
 
So, this evening I pulled off the cover of the motor junction box to look at how my 1R3's motor is wired up. I find nine motor terminal wires, numbered 1-9, and of course the three lines for the 3ph power- connected in a pattern that seems to match up with a parallel (low voltage) wye:
T1-T7-L1
T8-T2-L2
T3-T9-L3
(same apparent pattern as is shown at about 13 minutes, 45 seconds here: Motor Connection Diagrams (Full Lecture) - YouTube ).

I took an extra look in the box hoping that I would find a set of 10-11-12 wire leads (for a 12 wire motor capable of being connected up as either wye or delta), and that maybe someone had connected the motor up as a wye when it might have been designed to run as a delta... which (a delta-designed motor wired up as a wye) would definitely lead to an under-powered situation (putting out only about 1/3 of the HP of a delta-designed motor running connected as delta). But: no 10-11-12 wires - only the 1-9 - which seems to suggest that my machine has a motor set up only to be wired up as a wye. And from what I (think I) understand, if a motor was originally designed to run 240 wye, it'll put out under full power when connected up in a 240 wye configuration.

So the puzzle continues... I was hoping that I'd find it wired up for HV which would explain it not running right.

Ben or Mike or others- do you know if the motors in your 1R3s seem to be connected up as wye- or do you mind taking a look to see how they are connected up?

Thanks
 
Now check your starter heaters. They will have a number on them. If you just google the brand name and number, plus the words overload heaters, it will give you some pages with a chart that shows the amperage those heaters are set to cover. If they are rated for high voltage, the amp rating will be about half the motor placard rating.
 
Late this afternoon after helping family with some stuff, I decided to spend some time with the VN, and decided to see what the lubricants were really like before chasing too much more with the electrical gremlins. The stuff that drained out of the ram :ack2: was thicker than honey and was a mix of opaque sickly grey tan and dark black, sort of in different strata that didn't blend much while draining into the pan- sort of stayed as separate streaks. Stank much like hypoid axle gear oil. A black goopy chunk came out with the lube. Unfortunately, when further-exploring what the goopy chunk consisted of, once the goop was pared away, it looks concerningly like a single roller from a taper roller bearing. The lube in the cutterhead- unfortunately was even thicker than the fluid in the ram, although it was amber and vaguely translucent rather than the opaque like came out of the ram. To get it to drain well I had to stick a wire up the drain hole and in addition to the thick fluid, grease-like stuff clung to the wire. Before I realized that the chunk contained a bearing roller, I filled the ram and cutterhead to appropriate levels with #2 offroad diesel (similar to but a bit thicker and more lubricating than kerosene) and took the mill through the various gears. With the glop of doom out of the ram and cutterhead, the 1R3 can start and run in any ratio without tripping off, so it seems that my problem was not necessarily electrical. Seeing what came out, I am now unsurprised that it was tripping off. I've left the #2 OR diesel in it for now to let it continue to try to dissolve any more pockets that may not have come loose already. I should probably also tilt the cutterhead vertical to loosen up anything that didn't already get worked loose with the diesel in the horizontal position.

I am very concerned about finding the bearing roller (I assume that's what it is, it's about 0.28" at the thinner end and about 0.30 at the wider end). I found that (roller) part way while running it through the gears with the fuel in the gearbozes. I decided that I am unlikely to do tremendous damage in a few minutes that did not already occur over the course of who knows how long. Looking in from the small cover that comes off the top of the shifter casting, of the gear teeth that I can see which are clearly not all of the teeth) nothing looks in bad shape at all. There is a sort of rhythmic bearing rumble as the machine is running. I pulled the belt cover off and removed the belts; the motor bearings are a slight bit noisy, and when the gearing (unhooked from the motor) is spun by hand, there is some noise but nothing extreme- some of it is what I would expect from straight cut gears, but some of it- the rythmic rumble- seems bearing related. If I had not found the roller, I probably wouldn't give much thought or concern to the bearing rumbles, etc., figuring that it just goes with old machine territory- but it seems like something fairly extreme would have to happen to dislodge an individual roller from a bearing cage. The thought of disemboweling the geartrain (and then getting the shifters' racks re-timed when putting it all back together) is _not_ inviting, but then again, I hate to knowingly run the thing if I know that there's damage and that, without knowing the location or the seriousness, it could get worse. I'm not really a restorer- more of a user-preserver - but I do see these machines as having historic and heritage aspects in addition to their functional usefulness.

I'll probably try to strain the removed oil through some coarse screen or fine hardware cloth to see if there are any other 'chunks o' concern' in the oil.

I welcome thoughts and suggestions on practical approaches to appropriately addressing- but not over-reacting- to the roller in the oil. Right now it looks like the distinction between "official oil" vs "hydraulic oil" is looking a bit moot- anything I put in this is going to be immeasurably better than what just came out.

Thanks for the continued shared knowledge and encouragement.
 
When I took the ram gearbox on my No. 16 apart I found a bunch of bearing rollers in the bottom. Apparently, when they replaced the bearings in the machine (with truck axle grade bearings), they didn't think it was necessary to deal with the shims that control the pre-load on the bearings. They apparently ran the poor old girl until she would run no more:
IMG_7023.jpg
Surprisingly, there's no obvious damage to anything in the gearbox. I'll know more when I finally have time to put the new bearings in.

You definitely do not want to run your machine any more until you pull the ram gearbox apart, inspect everything and replace the bad bearing(s).

Cal
 
I know how you feel - I'm no machine restorer, either. I bought my machine having tested it under power and making cuts, so I figured it was good to go. That said, every single thing I've taken apart had minor (or major) issues that would have become larger problems down the road, so I feel like it was the right choice to go over the machine and make sure it's 100% rather than using it and hoping it holds together. Unfortunately I don't think anyone can tell you in good faith to run it with the bearings in such poor shape - losing a roller automatically puts a bearing in "poor shape" category ;) - and also with the ever-present danger of having loose parts (either in there already, or, uh, newly generated) sucked up into the gear train which would surely ruin the gears involved in such an incident. You can run it as-is, but ruining several gears in the gearbox may be a "scrapping event" for the machine - replacements can't be had, so you either make them or commission them. Making large internally splined gears requires you to have, at least, a set of gear cutters, a dividing head, a rotary table, and a vertical shaper/slotter attachment, and another functioning mill. I don't have real knowledge of what it would cost to have them custom made, but I wouldn't be surprised to see 2-3 gears run into four figures.

It's really not too hard to time the shifter mechanism - don't let the thought of that stop you. As I mentioned, I messed up the timing of both my shifter arms but once I figured out how to set it right, it couldn't have taken me more than 45-60 minutes to set and verify everything. For better or worse, you'll be doing much harder things if you tackle the gear train :)

Last thing - be sure to open up the plate on the side of the cutter head and really clean that out in there. You mentioned you found something like grease in the oil; it's possible someone forced too much grease into the bearings and it pushed past the oil seals. Regardless, it's very easy to open up and that way you can see what's going on and really clean it out. While you have it open, you may want to check the bearing end play and if that's good, check the gear lash as you'd be able to adjust it while it's opened up.
 
Thank you Cal and thank you Ben. All that you say makes total sense to me (one roller amiss brings to mind shredded up cages poised to fail further, shafts going unsupported under load, and colliding irreplaceable pieces). My own tendency is to try to do things as best I know how/ am able to learn, and can manage to pull off, but I have also learned the hard way that with old machinery and buildings "while we're at it" can pave the way to utterly uncontrollable time, scope, and budget, and at moments brings on more trouble than if something had been left alone, so I try to moderate or at least reflect on my natural strong tendency to want to dive, and address, full depth. Hearing it from others helps me know that yes, this isn't just my own unmoderated inclination to dive in deeper. This machine seemed in strong running condition and all external indications are that it had a far less hard or rough life than average, and much of my goal in getting it was to get a horizontal-capable machine that was (as best I could tell) close to ready to go with no apparent need for major work. So it's an adjustment to realize that it's got these inner major issues.

I am left wondering what could have happened to a machine that seems not to have had a lot of use, or hard use, to have bearings coming apart. Though maybe that ultra-thick glop of doom that someone put in it as lube could even have created hydraulic drag (under high RPM start-off) within a bearing cage that led to distortion and failure. As I drained the glop and found the errant roller, I thought that maybe someone put in the glop to quiet bearing noise, but maybe it created bearing trouble. I guess the how and why is moot, it's now down to where I go from here, and it is such a unique machine that so well-fits what I want, that it's worth doing it right.

I should definitely pull the cutterhead side cover to verify that there hopefully isn't any major damage in there. I take tentative comfort that I didn't see any dark or shiny stuff coming out of the cutterhead's drained fluids.

Ben- since you have had the cutterhead thoroughly off and apart, what would you guess is the fully assembled weight of the whole cutterhead? Since I am going to have to pull the shafts in the main ram, I am wondering about dis-mounting the cutterhead as an assembled unit before disassembling it (and maybe after checking end play) if it is not too heavy (maybe if all is reasonably well in the cutterhead I won't even need to disassemble it).

Thanks again for the insight and encouragement.

I see an upcoming thread: "Journey to the Center of a VN 1R3"
 
By the way, in expecting that I will be bearing-shopping to some greater or lesser degreee. I realize that bearing precision matters a great deal in spindle bearings. It probably even matters a considerable amount in the shaft out of the ram gearbox that has the bevel gear that intersects the spindles's bevel gear. But on the two "earlier shafts" (closer to the motor) of the ram's gear train, I assume that bearing precision is not necessarily quite as crucial. I'll want to get the best bearings that I can reasonably find and afford (and I have sometimes in the past found some very high grade bearings in matched sets at very reasonable prices on ebay, just by keeping an eye out and eventually finding someone asking a pedestrian price for upper-echelon bearings) but I'm not going to be able to be sinking unlimited sums into bearings.... Thanks
 
I think you're making the right choice. At least, you can start with a fairly low commitment item: Pull the top of the transmission off - you will be able to really look at everything, be able to inspect each bearing and, using some aids like a small camera or boroscope probably even account for all the rollers. In doing so you've only created a little work to get the shifting mechanism back together. If you find the bad bearing, you may be able to replace it easily as you can access three of the six bearings externally from the right side of the machine.

Ben- since you have had the cutterhead thoroughly off and apart, what would you guess is the fully assembled weight of the whole cutterhead? Since I am going to have to pull the shafts in the main ram, I am wondering about dis-mounting the cutterhead as an assembled unit before disassembling it (and maybe after checking end play) if it is not too heavy (maybe if all is reasonably well in the cutterhead I won't even need to disassemble it).

I never had the cutterhead off while assembled - only the empty casting, with nothing inside. Still, it wasn't light - I would guess at least 75 pounds, with the spindle, bearings, locking rings and ring gear pushing it up closer to 100. This may be obvious but the cutterhead must be drained of oil before removal. The oil "seal" on the ram side is a damn-near-interference fit with a spud protruding from the ram beneath the transmission bevel gear. Using my cheap no-name boring head the other day to make a few holes to loose tolerances I'm marveling at the precision required to make these (and other) machine tools :eek:

I hate to say it but I am also glad I pulled the spindle and replaced the clay, er, grease that was left in my bearings. But you can do that any time and the ram requires fairly immediate attention.
 








 
Back
Top