Post Re-Chroming: Stem Diameter Problem! Solutions?

[Cheesedisease]

I just got a GB KROMO Spearpoint stem re-chromed and unfortunately it has come back with it's diameter somewhat below 22.2mm.
Think it now measures around 22.02 mm with digital calipers. Anyway, so much reduced that it won't tighten in the fork steerer adequately.

This is my first experience of getting anything chromed. Anyone any experience of this happening?
It went to a place with experience of bike parts, via a fantastically helpful and reputable bike shop I've used before as they have very good experience of vintage parts, so a bit of a surprise.

Any solutions?
Could the stem shaft be further chromed to widen the diameter?
I imagine no one would shim a stem!? Don't think steering is something I want to mess with.

Many thanks for the help.

Daniel

ps. if anyone is interested in a beautiful steel stem that would probably now fit an old French sized fork steerer, feel free to get in touch!
Seriously, other wise it's sadly going to end it's days as nothing more than a fancy paperweight.

 

[willhouse]

A friend just had a minor issue with a downtube shifter bolt re-chromed which came back shrunk and tapered... not sure why it did it, but I think some things plate better than others.

 

[pigman]

I'd shim it with coke-can material and use no grease etc.. Remember when youre riding, youre not really stressing or heavy levering the steering, youre just guiding the bike.

 

[roadking]

If the chromer is not a specialist (i.e in delicate parts-bicycle, motorcycle, small car parts) this problem will certainly occur.

The object to be chromed has to be dechromed, then polished to effect a good surface to begin the replating process...in the old days the polished metal was plated with another metal before the chrome was added.

All these processes reduce then add to the item being plated.

If the polisher gets carried away and removes too much metal then that means you item gets smaller. Like everything the skill and time goes into the preparation.

Personally I've never had this issue - I always interview my platers if using a new firm!

Roadking.

 

[Cheesedisease]

Many thanks for the replies.

Pigman - it would really be okay to shim? There's an awful lot of fore-aft movent. Feels similar to a slack headset. I know the shim would take up that slack, but is there really not enough stress on the steering for it to come loose in anyway, even under hard braking?

I'd figured it was in the cleaning and then prepping the steel it occured.

I'm surprised as it is a place that does deal with bike parts regularly. I deliberately chose as it was sent it via a bike shop that frequently deals with restoring a lot of vintage parts for people and for himself. I did this as I knew there would be risks, so went there to hopefully avoid them! I'd even put a note in to say that I'd rather accept any pitting that would need too much preparation polishing to get rid off.

Guess I'll chalk it down to experience. I hope the crankset I had done is okay. It looks lovely, but I'm now worried it might be structurally suspect in some way? Hope not! I've heard of rechromed stuff snapping?

Roadking - So as you say I figure, it's been 'over prepared'! I guess chroming againg won't help then. Can you recommend anyone to do re-chroming for future projects?

Many thanks, very much appreciated.

 

[pigman]

sorry, cant give you scientific reassurance, but I would shim it. The hardest stresses I reckon are out of the saddle climbing. I'd shim it enough to take the rocking feeling away and so that it doesnt spin in the steerer. Make sure the shim is deep enough (area wise) so that the whole inserted portion is shimmed.
youse listen to me, youse takes ya chances ...

 

[Aqua]

If this were mine I would take it back and show them the problem. A reputable ,competent firm would replate it for you back to the correct size.The term "triple plated " is/was used to describe quality chrome plating,this does not mean three coats of chrome but, first copper,then nickel,then finally chrome. This process has many advantages. the copper provides a good key to the steel,offers a good rust protection,and can be applied in different thicknesses to restore an item to its correct size or fill imperfections such as rust pits. the nickel is used as a bond for the chrome I think.
I have learned all this the hard way with classic car parts.Most platers don't seem to understand restoration work and just put it in with their main jobs.

 

[Cheesedisease]

youse listen to me, youse takes ya chances ...

Don't worry, if I try it and anything goes horribly wrong I'll probably not still be around to sue!!!

Reckon I'll give it a go, at least as a 'prop' to help finish the build once I get the wheels done.

I'm deciding between a Titan Maes Kint stem & bar and a GB KROMO / GB Maitland bar set up. I can at least see what I prefer if I shim the stem, as the two bars are both very contrasting bends. If need be, I can track down another GB steel stem if that's what I do prefer to go for. I'd also worry about it seizing if I shim it permanently with no grease, and never be able to remove it?

Taking me ages to get this bike done due to changes of mind, redundancies and unplanned family visits anyway. So I should just take my time and get it done right. My bikes are never ready for the summer as planned, always end up taking at least until things turn autumnal!

Or I might try to sell it or swap it with the necessary clear caveat.
Someone might want a luxury paperweight, have a French fork steerer, or just to be a greater daredevil than me and not think twice about happily shimming it!

Thanks again,

Daniel

 

[Cheesedisease]

Aqua...

Pretty sure it was triple plated, as they offer nikel plating, which I realise is the metal plating stage before the chrome.

I fully agree on taking it back, it's just a bit too far away. I did contact the bike shop where it was sent from. They've been super helpful through this restoration, with lots of advice, and already happily paid the carriage costs to correct a misshap when the lug lining was missed by the painters. Been in touch with them so they'll get back to me. I just hate when someone is always helpful and you feel like you are becoming a pest!