Need help with drill spindle!

[PeterT]

That's interesting. I'm not sure if I'm interpreting the sizing chart correctly but the ID/OD (d vs D) difference is nominally 1mm different. A bit thinner in the small diameter range, a bit bigger in the larger ones. So nominal 1mm = 0.039", so 1/2 thickness (=the annular gap) would be about 0.020". This drill application required only 0.001" shim.

So this system might require you to select a next bigger bearing maybe? We chatted about that early on in the post with the possibility of going up to 17mm bearing (0.669" ID) & machining a sleeve.

 

[PeterT]

The last thing I wanted to try was the same Loctite retainer on the carbon steel shim on my 1018 scrap. Same result, peeled off just as easily as the brass. You can see the green stripe within the red felt pen lines where its entirely cured but just no gription.

Then I tried medium viscosity CA glue (between the blue lines). It stuck better but not anything like what I would call a permanent bond. It would probably stay put if you were sliding a loose fit bearing over it but I'm not sure how much shear stress it would take before failing

Very strange. I don't know what to say about this anymore. I know CA like a bit of porosity. But makes me wonder how bearings can stay so firmly stuck to a shaft with normal Loctite retainer where you sometimes have to beat them or torch heat to remove. Maybe its purely better strength in shear (like pushing a bearing off along a shaft or machining a part bonded to an arbor face) vs tensile strength (peeling back a thin stock). Interestingly the 'glue' is always fully cured to the shaft but not to the shim stock, I need to talk to a Loctite engineer, this will follow me to my grave LOL!

 

[YYCHM]

I've never had any luck using Red Loctite. Gave up on it.

 

[PeterT]

I've used quite a few Loctite flavors, mostly on fasteners but also bearings & bushings. Never an issue. But this shim thing is just perplexing. I do know that it can loose its potency over time, i am guilty of that. So now I date the bottle with a marker.

 

[YYCHM]

I've used quite a few Loctite flavors, mostly on fasteners but also bearings & bushings. Never an issue. But this shim thing is just perplexing.

How do you know it's actually done something on a bearing or bushing unless you have tried to remove it?

I've used blue to keep screws from coming loose and that works, but red as a permanent solution no.

 

[PeterT]

The blue & red I typically use on fasteners for removable & 'more permanent' bond. For bearings I typically use retainers like 609, 680... depending on the annular gap & other variables. I've done some tests of certain parts & it required vise pressure to fail. I've also had main bearings stuck pretty firm to model engine crankshafts for example & the only recourse was heat or in a few extreme cases dremelling a slot through the race & laterally cracking it open with a screwdriver blade. best to consult the product literature, but its almost overwhelming.

 

[YYCHM]

609, 680 ? Never seen anything labeled that on a shelf. Where do you source that stuff from?

 

[PeterT]

retaining compound
https://www.kbctools.ca/products/search/loctite?v=j&facet=[["catname","catname","Retaining Compound"]]

https://www.amazon.ca/s?k=loctite+680&ref=nb_sb_noss_1

Loctite products general
https://www.kbctools.ca/products/search/loctite

 

[PeterT]

A few more pics to log. I tried regular JB Weld with both brass & steel. It seemed to hold a bit better than Loctite or CA. I was able to turn it down to basically nothing. So might be a cheesy but still viable method to 'build up' worn or mismatched shaft thickness to a bearing ID.

But again, once I lifted up an edge I could peel back the shim without a lot of effort. So I think the 'peeling back' action is putting very high equivalent tensile stress localized on a teeny pencil line thickness at the leading edge line of adhesive. Once it lifts (fails), it perpetuates along the joint with minimal effort. I don't think its related to the material itself at all, but purely to this effect. A rigid bearing or collar could never be peeled back like this which is why we don't see it in real life. It needs to be pushed off axially, therefore the entire bonded surface area is resisting and in shear mode vs tensile, which is more favorable to the adhesive. At least that's my armchair engineering notion.

 

[Tom O]

The only other choice would have been to undercut then build it up to machine Giving it the thickness needed.

 

[historicalarms]

Man, I used red Locktite on a combine wobble box tapered shaft joint one time that the original key way had hammered loose on. Goo'd'er up with "red", sucked it tight as we could and went for supper to let it cure before use... we used that combine 5 more years and the neighbor bought it from us and used it 8 more years before retiring it...and that wobble shaft never came loose

 

[YYCHM]

Where is this project at? Still waiting for the new chuck?

 

[PeterT]

Dai can chime in but he picked up the spindle back in Aug when I assembled spindle with the steel shim stock. We tested the nice chuck he got with the assembly mounted in mill vise. Unfortunately it wasn't quite as good as the taper runout itself (which is kind of the hit & miss experience I have had with chucks at the best of times). But hopefully it will still make for a nice, accurate restored machine. He had some more work to do to complete the assembly so I haven't heard myself.

 

[DH930]

Sorry guys, I have been working flat out because I got a new job. LOL

The project is almost done. I needed to mount the controller to the drill press and installing the speed reader to the spindle wheel. Peter did an outstanding job on the spindle. The new chuck shows similar run out on Peter lathe but I haven't done any measuring since installed to the drill body. I probably won't be working on it until Christmas break now because I am anticipating a very busy period at work.

 

[YYCHM]

I needed to mount the controller to the drill press and installing the speed reader to the spindle wheel.

??? So now you have to tell us what the ultimate plan is for this reconstruction??