[Closed] Surely there is a cost effective way to fix this lovely frame....

Don't weld a plate in, just bob a couple of blobs of weld in place then machine to the correct dia

This does totally ignore any heat treatment issues

I'd look at sleeveing the headtube. Machine/grind out the headtube, Bond the some sleeves in and voila. If you can get the sleeve machined to just undersized of 1" 1/8 then you'll be able to ensure its square when you do I final ream through.

Coke can shims.

Blobs of weld:

Hmm, that's a good idea mate. Tbh I have had LOADS of DH frames welded and never had a problem if done correctly. I have a friend who works in a facility where welding to Nuclear standards is done so it is done to a very high level.

My mate also only 'poodles' along, never leaves the ground and barely gets over a jogging pace!

Sleeving: probably the best fix but could go wrong! I reckon this is the one to try though.

Can shims: done it before but this is far too far gone. I'd need a cans worth of alloy at each end!

See if you can get the headset cups knurled at a machine shop, has worked for me in the past.

Heres my idea..........

Try to measure the inside of the head tube to work out how much over size it is.
Then get a head set and get some press on over size sleeves made and press these onto the head set. You could make these from the head tube of a damaged (more damaged) frame. Cut off the length you need press them onto head set cups then hold cup in lathe and gently, carefully turn them down, (watch they dont fly off tho!) till just over size compared to your wonky frame. Heat wonky frame up with a hot air gun to get it to expand a bit then press your headset with sleeves into the head tube. Would probably get some loctite 648 onto the sleeves too!

betd

It's that far gone mate there is no chance knurling would work to be honest!

Not sure I'd ride that based on what you've said. How badly may they have damaged the main tubes? Anyway chris king will make you one if you have accurate measurements apparently perhaps Hope would too? Or loctite 270

I can't see getting a sleeve machined being cheap which is why I thought building it up with weld would be better

I'd suggest a good epoxy glue, worked on my old enduro with a badly flared headtube. After that Id look to modify the headset and not the frame.... I have also found some headsets shrink on fitting so dont cope well with reuse. Measure the headtube first.

Why not add material to the headset cups rather than the frame, they would be much easier to work on & it sounds as if you have the means to do it, that new deep headset you have bought sounds an ideal starting point.

Worth a go as it's the most disposable part.

Cheers.

How much does it rattle by?

Measure the headset and the tube, if the difference is less than 0.5mm (I'd be surprised if they managed to remove more than that by blasting) then just use this to retain it

http://www.ebay.co.uk/itm/LOCTITE-660-50ml-Quick-metal-Retaining-Compound-/221143631742?pt=LH_DefaultDomain_3&hash=item337d30077e

Good ideas all round. There's no problem with the safety of the frame, it's literally just the loss of 'friction' to hold the cups in, no other issues.

I think I have got the best idea yet from a mash up of some of the above... Cheers 2unfit2ride!

The deep headset we have is stainless...and about a 2" insertion at each end. I'm gonna get the cups' insertion parts welded over all the way round then turn them down to the correct size to be tight in the frame. Saves working on alloy for a start and will essentially be exactly the same as it should be, just a slightly larger headset!

There's a Germa company that machine headset cups for this situation, but I'm struggling to remember wh they are though at this point in time, they make really nice high end hubs as well it's not Tune though.

As a last chance saloon option, glue them in with Araldite

need a deep insertion cup headset.

if you're feeling bling

http://chrisking.com/headsets/hds_steelset

[img] [/img]

if you're feeling cheap

both are steel and once inserted arn't going anywhere.

I changed the forks on my dh bike a few years ago undoing to lower crown resulted in the the lower cup just falling out with it.

I fitted the syncros fr1 above and had another 3 years out of the bike

doh!!! re read the post

Aha yes

RESET-RACING.DE "http://www.reset-racing.de/presse/images/koehn_at_dirtmag_0807.pdf"

Thats' the fella the moment I posted it came to me.

Acros I believe.

It should probably go in the bin. Buy where' the fun in that...

My suggestion would be to bond in some headset cups using Devcon aluminium or titanium loaded epoxy putty or similar.

Failing that sleeve it or try getting some oversized cups turned but I'd avoid taking a welder to it or machining more material away...

GREEBLE: as in the first post pal, I already have a 2" insertion stainless steel headset. It doesn't even do anything over the standard hope one due to the configuration inside the frame. Thanks anyway.

Thanks everyone else, I think we'll try the over sizing of the steel headset we have. If that doesn't work the custom cups is the best option.

Thanks

try a fsa pig pro headset. there about £25 and the cups are made of steel. a simple headset but are a little heavy than most headsets but are good tight fit even in worn head tubes. iv used them in the past on jump frames

Use some Loctite bearing retaining compound...

[url= http://www.loctite.co.uk/cps/rde/xchg/henkel_uke/hs.xsl/retaining-4479.htm ]loctite site[/url]

Can't remember which number I used (660 I think), but I fitted an FSA Orbit headset to a steel frame as the headset was ovalised with the same symptoms as your, should fill in gaps up to 0.5mm. It's pretty much a permanent fitting, doubt you could remove the headset without damaging the frame.

fsa pig is what i was going to recommend

I would try an epoxy. Not sure which one is best though. But have you actually tried fitting the forks and a stem? Is there enoughmovement to lead to damage, or would the star nut hold everything together?

Thanks guys.

A replacement headset of ANY type (Pig etc) won't help, it's too worn, possibly by upto 1mm all the way round, not flared but eroded. It is still perfectly round.

I'm unsure if a retaining compound would do it due to the potentially high stress/ slight flex placement on the frame. I could try that.

In the state it's in now, even all done up it would be line running a headset with no bearings in it...clunky and loose!

Cheers all.

A bit of car body filler round the headset would take up the slack. Not as good as getting a headset machined to the right size, but it's cheap and cheerful.

Just going right back to the OP... It'd take a lot of effort to shotblast away that much metal and it wouldn't normally be that localised, or very even- it'd be bizarre for hte headtube to be eroded away that much and nothing else on the frame damaged...

What ever you end up doing I'd fit one of these to hold it all together.

http://www.bikepedia.com/pa/Item.aspx?itemid=371642#.UQhTmL8gGc0

TJ saved his tandem with loctite or similar.

Low cost, what's to lose?

There is a suitable Locktite bearing filler/ glue 660 (more like a liquid metal that sets) for this - we fit wheel bearings into race hubs which have over sized (as in racing with engines) with it, if I remember it will fill upto 0.7 mm (says .5 which is big gap but can go bigger just) it's expensive for a little bottle £30 but way cheaper than methods above. Main thing would be to get a good spread/ fill of it around whole surface of both cups, get them in and then before it sets fit the forks to centre every thing, then leave overnight to set.
I have also set very successfully rear triangle bearings on mtbs where the bearing housing has gone well oversize.
I would choose a headset where you can easily replace the bearings as once in the cups would be a major challenge to replace.
Link to spec
http://www.loctite.co.uk/cps/rde/xchg/henkel_uke/hs.xsl/fullproduct-list-loctite-4995.htm?countryCode=uke&BU=industrial&parentredDotUID=productfinder&redDotUID=1000000J02K

Northwind

Just going right back to the OP... It'd take a lot of effort to shotblast away that much metal and it wouldn't normally be that localised, or very even- it'd be bizarre for hte headtube to be eroded away that much and nothing else on the frame damaged...

The anodising process ,which involves acid ,can do some serious erosion if done wrong.
I have had parts anodised come back smaller than they went 🙁

Although other parts of the frame would be in a poor condition also.

It is Loctite 641 or Loctite 660,which is for bigger gaps, bearing fit you need but there is a limit to how much space it will take up.

HTH

Yeah, I wondered about that though should be even more indiscriminate.

O.p. - Maybe I'm reading this all wrong - but the solution seems to me to have been suggested a while back by 2unfit2ride. Get some 1mm aluminium sheet and make shims to fit around the flanges of your headset cups then press them in. In effect you are making the flanges "thicker" so they will now have the required interfence fit to hold them in. Plus you will have an even layer of material all around the flanges so they will be centralised in the head-tube, this would be very difficult to acheieve with epoxies or filler.

if it rattles glue it in

if they've blasted that much material away (or disolved in acid before anodising) would you not ne worried about how tin the tubes have got and how likely it is to snap?

Hmm - I cant see how a head-tube would "snap" - especially with that big brace either side. Might deform a bit more in use though if it geniunely has been made thinner. Still think shimming the flanges is the best option.

if that much material is missing from the inside of the headtube how much is missing from the down tube, seat tube etc (have you had a seat post or seat clamp in/on it yet?)

Sell the frame on gumtree ?

>if they've blasted that much material away (or disolved in acid before anodising) would you not ne worried about how tin the tubes have got and how likely it is to snap?<

This...

Doubt you could afford to lose a mil around the centre point of any of your tubes. ;-(

Can't see how shimming the cups will work - the bores are likely to be eccentric and they wont be concentric with each other. Best solution would be to have the HT machined then oversized cups made up / inserted. Or, bang the loctite in and align everything by nipping it up with the fork / stem.

As I say the HT might be the least of your worries - I wouldn't ride it myself if it's as bad as you say it is.

Good points from sssimon and theblackmount - is it [i]just[/i] the headtube thats affected or are [i]all[/i] the tubes thinner? (From the pic the cable mounts seem to be ok and all the welds look as normal) any excessive material removed should be obvious here I would have thought. Is there any play where the two halves of the frame join? As sssimon suggests have you tried a seat-tube/clamp yet?

How much does the frame weigh now?!

Can't see why anyone would shot blast the unpainted inside of a head tube that much without blowing holes in the thinner painted tubes. Could they have anodised the entire thing and then machined out the head tube?

How did they protect the threads in the BB - if a 1mm has gone from the headset, I'd expect them to have been destroyed?

[img] [/img]

+

[img] [/img]

Potentially stupid thought, but was the headset loose before? Did you remove it?

Ignoring all other issues regarding pivot bearing holes, BB thread, potential weakening and just dealing with the headset problem:

Do not shim it. If you end up slightly too thick/not round and force it you may split the head tube.

My immediate solution was the proper loctite for setting bearings. You may need it elsewhere anyway. It is designed exactly for taking out slop in bearings. Something like Loctite 660 (high strength repair retainer for up to 0.5mm) or failing that a decent epoxy.

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!