The Right Adhesive

[rws]

I tried to glue a small ball bearing assembly into a delrin sleeve. I used JB Weld and it didn't hold. I assume there is too much flex in the delrin? I tried that gooey yellow weatherstripping stuff, and that didn't hold either. We're not talking a lot of stress here, just basically holding it in place. Suggestions?

[davidh]

This to That (Glue Advice)

https://www.thistothat.com/

[ikdor]

Delrin doesn't want to be glued very much by most normal glues. There are exotic variants that will do it, but they will be hard to source and expensive.

For a moderate hold I'd try to rough it with sandpaper and try a few cheap epoxies to see if one of them holds enough. Two weeks ago it worked for me on PE, which also isn't supposed to work but does.

Igor

[Ian B]

Could you machine some fine rings in the bore in the delrin, something like tiny circlip grooves? This would give the JB weld / epoxy something to lodge against, and as long as the bond to the bearing is good, it should stay in place. Cutting a fine keyway along the axis would help to resist rotation too.

Ian

[johnd]

I stumbled into several tubes of Loctite 515 "Gasket Eliminator" years ago and use it for everything from thread sealer / locker to slightly loose bearings like you describe. There are other Loctite formulas maybe better suited but I think anything you try would work best if you can rough up the bore a little. Maybe just scratch it up with the corner of a file or something.

[TGTool]

I just purchased some CA adhesives from Tech-Bond Solutions and the kit includes a bottle of stuff called Poly Prep that allows a bond with polyethylene and other plastics that don't normally adhere. It's applied and allowed to dry so it must modify the surface somehow. This probably isn't the only source, so knowing that there's a chemical out there for that application you might use this outfit or another to get a bond with Delrin.

[firbikrhd1]

Not a glue suggestion and I don't have an accurate picture of your situation in mind, however I'll toss this out there; would it be possible to heat the ball bearing and press it into the Delrin causing it to be a sort of "press fit"? Perhaps the reverse would work too, warm the Delrin and press the bearing into it. Just a thought.....

[chipmaker4130]

Two suggestions:
1- If extra flex is ok, try the 'SuperBlue' silicone by Permatex.
2- If a stiffer but flexible set is required, try 'E-6000' from Ace Hardware, etc.

The yellow stuff which we used to call 'camel snot' is no good if you need to slide the parts together. Doing that will just peel/roll the adhesive off one or both surfaces.

[Fasttrack]

Why not press fit the bearing into place?