Jonneh

I want to glue the washers on my WI Eno hub to my frame. The replaceable derailleur hanger closes off the dropout less than its closure on the non-drive side, resulting in the washer eating into the dropout on the drive side, and inserting ever more wonkily. I've tried extra washers (wide ones), but that means that too few threads of the bolts contact with the hub, and they started to strip. I flip the wheel or remove it fairly often for one reason or another and I'm worried about damaging the frame irreparably, so bonding the washers to the frame is probably a lesser evil. In doing so, I can set the alignment to compensate for the more open drive-side dropout.

Which epoxy should I use for such a fix? I've got some J-B Weld 'J-B Weld' on its way. Will that do the job?

EDIT: The frame is 7075 T6 aluminium

berner

I would poke around this website linking to more specific websites for detailed info. Bonding to metal is a big topic.

easyupbug 

I have had good luck with JB with clean aluminum and other metals. Use acetone or lacquer thinner or at least soap and water. They don't recommend alcohol or anything that can leave a petroleum residue.

rumrunn6

Jonneh

Good to see. Looks like I bought the right one then, albeit not by coincidence (recommended by DaveSSS on here).

Great, I'm going to go for it, making sure to prepare the surfaces well (roughing up the surface of the washer). I hope to be able to stick it on without much volume of epoxy in the axis of the hub axle. Otherwise I'll end up with the stripping problem I started to experience with an additional flat washer (which is just a very disheartening problem to have, and I wouldn't wish it on anyone).

Andrew R Stewart 

The comment about cleanliness is golden. But remember there's dirt/grime/oils cleaning and there's corrosion cleaning. Both are needed to be done. One of the challenges to working with Al is that it will create a skin of corrosion within minutes of being cleaned to pure AL (alloy), as in being sanded or filed to shinny metal. So just cleaning off the grime/oils will leave behind that corrosion coating (which BTW is what anodizing is, a specifically done corrosive coating) won't end up with the surfaces being best ready. Scratching/sanding the contact area is strongly suggested, and being ready to paint on the epoxy right away to prevent the quick recoating of Al2O3.

When attaching the washer to the drop out with epoxy between them don't reef down on the clamping pressures right away. There was a debate around here recently about how thin a layer of epoxy, during the curing process, is best for the bonding task. Many of us feel that a mild initial clamping pressure followed by a complete tightening (whatever ultimate pressure is attained, likely less then many will think).

It's my opinion that this fix will not be a long term one. As well as a motivation to consider a better drop out material with the next bike. Andy

PS- As for the washer material SS can be pretty hard. Not a problem in breaking but can be for axle retention. A hard surface won't like being "bit into" by the axle end. Thus any possibility of axle slippage, everything else remaining the same, will increase with a hard drop out contact surface. Mix this with the crappy exposed cam with plastic pressure "washer" and a horizontal slot and you have about the worst case WRT axle slippage. I know this isn't exactly the OP's situation but mentioned for reference. I would suggest considering a mild steel washer. Still far stronger and long lasting then the AL drop out and soft enough for the axle's securing method to readily bite.

WizardOfBoz

All of what Andrew said, above, is important. I like a glue with some flex, and so use an industrial glue called G/Flex, by West Systems.

The point about mild steel washers is important as well. Super high quality washers are hardened, temperted, and ground. Probably best to use steel washers from the "Manchego Cheese" bin at Home Depot.

On edit: temperted? Sheesh.

Jonneh

Thanks for the comments Andrew (and Wizard). I didn't see them in time for the bonding session, and although I did clean the surfaces well (sanding followed by acetone), I didn't apply the epoxy to the aluminium immediately after its cleaning.

Sure enough, the fix wasn't a long term one. The washers came off today. I'm actually quietly pleased, first because the alignment wasn't perfect, and second because I just acquired a wheel with a cassette on it for conversion of the bike to a geared one for exceptional rides. An extra-long quick release would have been a solution even with the washers glued, but I'm glad they came off, all things considered.

I think this is going to be the best solution. As it stands, with the high quality super-hard White Industries washers, I have to tighten the bolts to such an extent that I fear for the health of the bolt threads in the hub. Some soft steel washers should help here, in addition to being easier on the dropouts (heat-treated 7075 as they may be).

WizardOfBoz

Forged and heat-treated 7075 is probably not gonna get squashed by a QR or a bolt. But if the point is to get grip, you could just use a serrated washer - this might work better.