How loose is too loose - headset cups

[ishaw]

Access to a press?
Try squashing the race, aluminium parts aren't to hard to enlarge. or press something through it. Obviously try it on a cheap old headset first.

Sadly not :cry:

 

[matt24777]

I'm planning on using loctite 638 on my loose headset cups it's a bearing retaining compound

 

[lumos2000]

i have the same problem with my Airbourne, also using a chris king :?

 

[We_are_Stevo]

I'm planning on using loctite 638 on my loose headset cups it's a bearing retaining compound

'NOTE: We do not recommend using Loc-Tite and/or similar products to make up for a loose fit as the load forces tend to exceed their holding power causing them to disintegrate and allow movement. While they may seem to work at first, they will usually fail in less than a year.'

I think they probably know what they're talking about...

 

[integerspin]

I'm planning on using loctite 638 on my loose headset cups it's a bearing retaining compound

'NOTE: We do not recommend using Loc-Tite and/or similar products to make up for a loose fit as the load forces tend to exceed their holding power causing them to disintegrate and allow movement. While they may seem to work at first, they will usually fail in less than a year.'

I think they probably know what they're talking about...

I have seen motor bike head races glued in with bearing fit and they loosened and made the hole bigger, but I know several people who have glued them in and they have been fine. I can't see you have anything to loose by trying it.

If your really in trouble with them I could possibly make an over sized cup to take a cartridge bearing. I was going to buy an Explosif with a damaged head tube, I bought a stronglight headset intending on making an oversized bottom cup.

 

[matt24777]

matt24777 wrote:
I'm planning on using loctite 638 on my loose headset cups it's a bearing retaining compound


'NOTE: We do not recommend using Loc-Tite and/or similar products to make up for a loose fit as the load forces tend to exceed their holding power causing them to disintegrate and allow movement. While they may seem to work at first, they will usually fail in less than a year.'

I think they probably know what they're talking about...

well loctite do have a range of potentially suitable products but i thought I'd try this one based on the following from their spec sheet:

"638™ is designed for the bonding of cylindrical
fitting parts, particularly where bond gaps can approach 0.25
mm and where maximum strength at room temperature is
required. The product cures when confined in the absence of
air between close fitting metal surfaces and prevents loosening
and leakage from shock and vibration. Typical applications
include locking bushings and sleeves into housings and on
shafts."

And also:

"For Press Fitted Assemblies, apply adhesive thoroughly
to both bond surfaces and assemble at high press on
rates."

It kind of depends how big the gap is, If they are "slipping" in but with no "slop" I can't see this being a great problem.

Mine has "slop" on the bottom cup of about 0.2mm (0.1 per side but not all the way round) :? so I'm hoping this stuff that is good for up to 0.25mm will do the trick.

Sounds like it's spec'd for stuff that takes far higher/frequent loading than my headset will. (I Hope)

for various loctites see http://www.loctite.co.uk/cps/rde/xchg/henkel_uke/hs.xsl/fullproduct-list-loctite-4995.htm

 

[ishaw]

Right, loctite has come up and the jury seems to be out. I'm not sure my problem is severe enough to allow but I may try a thin shim. If this works would it hold up better than loctite?

 

[unkleGsif]

Maybe a combo of both?
Loctite the shim in placen then insert the cups


G

 

[ishaw]

Maybe a combo of both?
Loctite the shim in placen then insert the cups


G

I was contemplating that, though I may not be able to fit a shim in as there is no play, it's just not tight.