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I suspect that as mentioned above, if you got accurate measurements and speak nicely to Hope they 'may' make you some cups to fit. Their cups have replaceable bearings so in the event of one wearing out then you can leave the new cups in place and just take the bearings out.
Ano process eats metal.
Taiwan have a "frame lightening" process where you just leave a frame in ano bath for a while to lose weight.
I found out about metal eating when I had some hubs anodised and the bearings could be " thrown in from Barnsley" rather than being a "big hammer fit".
It’s a pretty common repair problem in industrial engineering, and there are a few off the shelf solutions;
Ready made sleeves;
http://simplybearings.co.uk/shop/Engineering+Parts-Shaft+Repair+Sleeves-Metric+Shaft+Repair+Sleeves/c4713_4847_4849/index.html
Tolerance rings;
http://www.wixroyd.com/en/catalog/standard-parts/transfer-rollers-and-tolerance-rings/tolerance-rings
Or any of the suggestions above
I'd cut the head tube off and take it to frame builder and get a new one welded on -1 or 2 degrees. Then I'd polish it to few inches down the toptube and downtube. It'd look alright and it'd ride better.
As said above (a few times tbh) it's not the 'retards' who blasted it, the person who stripped paint from an the downtube without cutting it in half didn't then erode the inside of the headset through error or spite.
I would Epoxy it, it's a good solution, it's not like it can go anywhere if it does fail to hold together.
Get the headtube reamed to take the whole depth of the deep insert cups, that'll give you at least some engagement that's the proper fit to hold it central. Then add plenty of JB weld and press it in and leave it somewhere warm to set for a good long time. It'll be completely fine, I've fixed a badly ovalise headtube by JB welding the bottom cup in before and that was on a bike that used to get a lot of very hard use (big drops and jumps etc), it was fine, didn't even creak.
Fixed it today. Thanks for all the thoughts...it was as a result of sandblasting, the guy who did it said today. Basically they said there was old Powdercoat in the tube so he thought he'd 'clean it up' as a result he took quite a bit of material off of it. Not overly helpful but not done on purpose...he knows now.
My initial thought of 1mm was way to much, just seemed like it when I stuck the headset in. Infact it's .5 if that. I had the 'step' taken out so upper and lower 2" cups go all the way in and had some shims made to ensure the cups grip for their whole depth on the inside of the tube.. I also used some locktight 660 to hold it all permanently (hopefully!)
Thanks all, he's just happy he can ride (albeit a mile behind everyone else)
I have a brand new WTB headset that rattles in any headtube - bottom worse than top cup.
Have you double checked the headset?
(If anyone want's and undersized headset, yours for a beer voucher and postage...)
Yes I did. A used HOPE (that was in it) a new Syncros sealed one and finally the Nuke Proo SS (deep one) that's been used to fix it.
Just looking at how much metal you have in the headset, you could probably drill through and get a couple of bolts in there too. 🙂
Hello,
I am a little surprised that blasting operation has increased the internal diameter of the head. I am wondering if you can see some uneven abrasion marks on the inside?
To fix it I certainly would not do any welding to the frame. I also would avoid removing any further material.
I'm not sure what workshop equipment you have access to but I would do the following. (you need access to a lathe)
Take the headset cups that you have measure the OD and then the ID of the head tube. Then work out what the difference and what you need extra on the cup.
Put some bar in the lathe and make a hole in the centre so its a super tight fit on the cup (the part that goes in the head tube). Then part of the right amount. The heat it up and insert the cup into it. Once its cool, put it all in the lathe again this time holding the headset cup and machine down the added sleeve until you have the right OD. Then bingo!