Need help with drill spindle!

DH930

DH930

Member
PeterT said:
In this picture, would the assembly go like:
- install left bearing
- install pipe sleeve
- install right bearing
- install spindle driver part over this assembly

- is the sleeve an actual part or something you are wanting to adapt?
- does the end of sleeve rest on the inner bearing rings but basically slides on arbor shaft?
- what bearing number is the 'new' bearing you were referring to? 5/8" = 0.625" maybe? And that comes in 35mm OD?

- any chance you could go to a 17mm ID x 35mm OD bearing? Turning a ring with ~ .025" wall thickness (.620" ID x 0.669" OD x bearing width) is more do-able. Still a bit delicate but I think do-able.

- the brass shim stock kit I have is 0.001, 0.0015, 0.002, 0.003, 0.004...
So 0.002" would be likely thickness. It might work but it also might be a flaky solution.
Click to expand...

The assembly order is as follow:
- install left bearing
- install pipe sleeve
- install spindle driver
- install right bearing

Q: is the sleeve an actual part or something you are wanting to adapt?
A: the sleeve is an actual part of the assembly and nothing is needed for this part. I was referring to if the spindle was to be replicated.
Q: does the end of sleeve rest on the inner bearing rings but basically slides on arbor shaft?
A: Yes, it does.
Q: what bearing number is the 'new' bearing you were referring to? 5/8" = 0.625" maybe? And that comes in 35mm OD?
A: The replacement bearing is 202SZZ3 with OD 35mm or 1.378", ID .625"

The bearings capped the driver so that the inner ring of the bearings fit tightly on the spindle while the outer ring of the bearings fit tightly on the driver's opening. The tail end of the driver has threaded opening and that is where you tighten up to hold the bearings/driver onto the spindle. There are other parts that attached to the tail end of the spindle where the pulley wheel integrate with the spindle and the drill head.
 
DH930

DH930

Member
PeterT said:
I think I understand now. The bulge is at the end of the taper section that fits the mating chuck seat taper? Do you think the majority of surface (green arrow) is in good shape, it has the proper taper etc? The gouges are not pretty but wont affect fit as long as green area OD is still true (circular & correct taper). If the spindle was held in lathe & the red area was carefully taken down to conform to green area, but not removing any green area, you stand a better chance of fitting the chuck taper ID. Right now the enlarged red area is interfering with the taper so it probably bottoms out & the chuck can hinge on some angle.

Now if the spindle was hammered laterally so the taper section is bent off-axis, that's not easy to 'un-do'.
Click to expand...

Thank you for that little illustration showing the bulge part. You are correct in regards to carefully shaving that off without touching the green part. The angle is correct and the chuck I have is brand new (NOS) of the correct chuck for this drill. The angle of the spindle and the ID of the chuck do matched perfectly. I don't believe that the spindle was hammered laterally because I put a straight edge to it and if looks perfect. This will all be confirmed once the spindle is on the lathe.
 
DH930

DH930

Member
I just looked at the parts diagram that Rudy (RobinHood) posted and noticed that I've used the wrong description for the quill. The spindle driver which I used in all my previous posts is referring to the quill parts #27.
 
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PeterT

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Premium Member
Reason I was asking about the sleeve is if you could go with a 17x35 bearing, then it would be much easier to turn a metal spacer ring on the lathe sized to fill the annular gap between bearing ID and shaft OD. (Like the shim business but thicker). It would be nominally .025" wall thickness which is quite thin but worth a shot IMO because it would solve all your issues. But the inner race of 17mm ID bearing will be a slightly different thickness than 15mm ID bearing & that might mean the end of the sleeve might interfere with the seal. But that would be relatively simple to turn down the end of the sleeve OD slightly to accommodate that.
 

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DH930

DH930

Member
PeterT said:
Reason I was asking about the sleeve is if you could go with a 17x35 bearing, then it would be much easier to turn a metal spacer ring on the lathe sized to fill the annular gap between bearing ID and shaft OD. (Like the shim business but thicker). It would be nominally .025" wall thickness which is quite thin but worth a shot IMO because it would solve all your issues. But the inner race of 17mm ID bearing will be a slightly different thickness than 15mm ID bearing & that might mean the end of the sleeve might interfere with the seal. But that would be relatively simple to turn down the end of the sleeve OD slightly to accommodate that.
Click to expand...
I guess using 17mm ID bearings could work just as long as the annular spacer ring is made out of steel and it is perfectly fit to make the bearings snugly fits on the spindle. The height should also matched with the bearins. You might onto something here.
 
RobinHood

RobinHood

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Premium Member
just went through your post again and saw the WT-33 service bulletin. From it, it appears someone has messed with the spindle before. The bearing seat is supposed to be 0.625 as per the document with a special SKF bearing with a 0.624” bore for a press fit. You state the actual bearing seat measurement is 0.620.

81E52931-2BB2-4E72-B685-03ABAB855672.jpeg

if the 0.620 bearing seat runs true to the spindle and is cylindrical for its length, I would use what Peter has suggested: 0.005” shim stock and a 6202/16-2RS (16x35x11) like this

https://www.qualitybearingsonline.c...bearings?_bc_fsnf=1&Inside+Diameter+(mm)=16mm

so your stack up will be 0.620+0.005 shim all the way around => 0.630”. 16mm is 0.6299”. That will give you a very light interference. Maybe put a bit of medium strength locktite for peace of mind. You can use all the original components and it should be at least equal to new.
 
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PeterT

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Rudy, what do you make of that primer verbiage? Do they mean to build up the shaft OD? Or, as in Loctite surface primer (a catalyst actually) to activate the retaining compound? I wouldn't think regular paint primer could be counted on for a bearing surface, but what do I know.

The thing that kind of bugs me about the shim stock is getting the bearing over it. I was thinking like 0.0005: slip fit so you have some wiggle room & then the Loctite will make up the gap however it self aligns. But where best to apply the Loctite - between shim & shaft or between shim & bearing? If it was stuck on the shaft then a new bearing could go over without much fuss.

I'm going to check the shop again. Seems I have some aluminum adhesive tape. If that is right thickness, then it could be applied to shaft without initially fussing with bearing. Push bearing on, then trim excess with exacto knife. I just don't have a sense for how much lateral load the shim has to take. I mean even a steel bearing 'floating' in a Loctite filled annular gap to steel or CI hole isn't metal to metal for the entire diameter even though it may have a point contact somewhere around the rim.
 
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PeterT

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Yes I think they mean build up the surface with primer. But notice its in 2 stages - mask, spray, cure, install bearing. Then repeat again for other bearing. I don't know much about powder coating but if it was done in 1 application (2 patches) then the lower bearing would have to get past the upper surface without scraping it. Otherwise it would need 2 separate applications like the primer bsiness & therefore individual oven cures. Seems like a lot of effort & maybe expense. I've never heard of these 'paint' type buildups but I am certainly no expert either. Shim stock seems kind of flaky too but whatever works & is easiest.

I checked & have 2 kinds of adhesive metal tape, 0.0025" and 0.002" thickness. I'm not sure what the industrial application is. I'm pretty sure they are both aluminum. The 0.002" is 2" wide roll, kind of reminds me of heat proof ducting tape. I rolled it on some 5/8 stock & if you burnish it down it seems relatively flat & consistent. But I think the bearing would have to be a slide fit over it, either by design or warmed up, otherwise I think the race will basically just scrape the tape off. You are welcome to try some.

I could machine a test collar for 17mm bearing idea just to see if it could be done (.025" wall thickness without distortion). If it works that would provide another option. A press fit would probably be the norm with steel bearing on steel shaft but with these 'sleeve' ideas, I'd be tempted to see if Loctite slip fit would allow you to get it in position & hold. 609 has a max gap fill of 0.005" (3000 psi strength). 680 is 0.015" (4000 psi).
 
DH930

DH930

Member
Wow. Peter, you are amazing. You really taking this to task. I really appreciate you putting a lot of thought into this. It is a bit challenging since there is no perfect replacement bearings. Is there any places where you can send to have old bearings refinish like replacing ball bearings? I wonder how much would cost if such a service existed?
Rudy, the .624" in the document is referring to the dimension required for .625" bearings that I'm using. The primer suggestion is to build up the spindle shaft up to make up the .004" gap. The reason that it is in two stages is because you have to install the first bearing then the inner sleeve, then the quill, and then the second bearing. The bearings are tightly pressed into both side of the quill.
 
RobinHood

RobinHood

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Premium Member
I believe the primer is to “build up“ the shaft so that there is some interference and thus no sliding. Never heard of that process - they must have tried it out, so obviously it works.

we know that the spindle is 0.620. Dai already has replacement bearings with 0.625 IDs. I think the best route is the use 0.0025 shim stock at each bearing and locktite, if needed. My idea of using a 6202/16-2RS was assuming no 0.0025“ stock is available for purchase; only 0.005” one was. Using shim stock could be done in-house and the DP made operational relatively quickly.

following the original “special bearing size” as W-T used it route, is more $$s and takes time. If I were going to do it, I would try it on an old 15mm ID bearing first to see if I can open it up to 0.620”. Probably need to make a special fixture to hold the bearing during grinding. And the bearing should not heat up; there should be no grinding dust going in; after grinding the bearings need cleaning and re-packing.
 
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PeterT

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Dai, you are welcome to try the shim stock method from materials I have. If we go with assumption 0.620 shaft and 0.625 bearing ID, the nominal thickness required would be 0.0025"
I have a brass shim kit contains 0.001, 0.0015, 0.002, 0.003, 0.004... So 0.002 might work with slide fit & Loctite just depending on a bunch of variables you will only know my trying the fit. Theoretically a 0.001 and 0.0015 could be added together but I suspect will be fiddly positioning these thin bands & bearing on top. The 0.003" thickness might work (interference) but the trick is to not crumple the brass by installing the bearing over it, its literally paper thickness. Possibly you could warm the bearing & slide it into position, but I have only done this on open bearings (no urethane coated dust covers or grease inside). I checked KBC & seems like these are the standard brass thicknesses available, at least that they carry & no better metric solution.
https://www.kbctools.ca/products/pg...=j&facet=[["catname","catname","Brass Shim"]]

Alternately there is the aluminum tape I have in 0.002 and 0.0025 thickness. It has adhesive so would stick OK. But the material seems kind of fragile compared to brass so same bearing push-on issue. For that matter adhesive (Loctite if you were certain) could be used on the brass to pre-position a band on the shaft.

Sorry I don't have any experience with precision grinding bearings but I think it would be quite involved to do it right. I have a bit of amateur lapping experience but its typically a zero to 0.002"removal/finishing method. Taking off 0.015" from your 15mm ID bearing is way outside the lapping range, especially being hardened material.
 
Johnwa

Johnwa

Ultra Member
I have .001 and .002 steel shim stock. I assume it’s a bit more rugged than brass. Perhaps .001 with Peters .0015 brass on the inside. You are welcome to a piece of either size.
loctime 641 is used for bearing fit ups but I haven’t found how much gap it will fill.

I’m surprised no one suggested building it up with spray welding.
 
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Tom O

Ultra Member
Johnwa said:
I have .001 and .002 steel shim stock. I assume it’s a bit more rugged than brass. Perhaps .001 with Peters .0015 brass on the inside. You are welcome to a piece of either size.
loctime 641 is used for bearing fit ups but I haven’t found how much gap it will fill.

I’m surprised no one suggested building it up with spray welding.
Click to expand...
I haven’t tried the spray welding kit out yet I’ll see if I can get my butt in gear on that.
 
DH930

DH930

Member
Holy smoke. That is much more complex than I could ever accomplice. I thought it was coming from a spray can. LOL
 
DH930

DH930

Member
Johnwa said:
I have .001 and .002 steel shim stock. I assume it’s a bit more rugged than brass. Perhaps .001 with Peters .0015 brass on the inside. You are welcome to a piece of either size.
loctime 641 is used for bearing fit ups but I haven’t found how much gap it will fill.

I’m surprised no one suggested building it up with spray welding.
Click to expand...
.002 steel shim stock might be the ticket here. I can locktite to the shim the bearing and then press fit onto the spindle.
 
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