Repairing fork thread

[bobafett]

Got an old set of ashtabula forks and the thread is a little chewed up 

Nut spins on fine but then hits the chewed part and 

I know you can re-thread with a die set but buying a set is expensive and i don't want to hire unless i'm definitely getting the right thing 

I'm also woried about TPI of the forks Vs TPI of the die set etc.

Anyone done this before ? Help 

[MartyC]

Try a good local bike shop, they should have the tap and dies already to clean them up.  If they are worn away you could get a welder to build up the thread area with weld and then have the thread re-cut  .

[bobafett]

Try a good local bike shop, they should have the tap and dies already to clean them up

You know I never even gave a LBS a thought - something about always wanting to do things myself i guess 
Right, yellow pages it is then - nice one marty

[Peter J]

Where are you based ? I might have a die to do it ?

[bobafett]

North West mate - bit far from you i think 

If you'd be willing to post it (just the die) i'd pay for postage both ways 

I understand if you don't want to though 

[Peter J]

My brother in law runs an engineering company so if you were on the door step I could have got it done for you.....he also has (a few) cnc lathes that do thread cutting

Just a thought bud 

[bobafett]

Never mind matey - thanks for trying though, if i was closer i'd have deffo taken you up on that 

[currio]

Mr. Fett, the solution to this problem does not always require the purchase, or hire of specialist tooling. i.e thread die.
If you know a decent Engineer who is local, there may be another solution to your current predicament.
It is possible to repair damaged threads using appropriate hand tools, specifically in the case of threads, a knife edged needle file.
I may know someone who would up to the job.
Let me know,
Shaun

[bobafett]

 

OK, OK -  piss taken (private joke folks)

I'll give yer a call shaun

Mr.Fett - tut tut 

[fouronethreeoh!]

You can also get thread files    unf/unc for fork threads 24tpi i think. Just depends how damaged the thread is.
http://uk.rs-online.com/web/search/searchBrowseAction.html'method=getProduct&R=5423408

or park tools, listed at £225 at wiggle, ouch  
http://www.parktool.com/products/detail.asp?cat=49&item=FTS-1

[bobafett]

Thanks fouronethreeoh! i might look into that if i'm not locked up for killing currio with his needle file 

[currio]

Right, pi$$ taking aside, the thread for 1" BMX forks is either (I am still not sure)  1" x 24, or 26 TPI (threads per inch) BSC. (British Standard Cycle)
A BSC thread has 60° thread angles, as does the UNC, or UNF version.
There are still differences between these thread types, but this would only matter if we were talking new for new.
The bottom line is, in this instance, clearing the debris from the bottom of the thread (root diameter), and damage to the thread flanks.
Hence my suggestion to use a needle file.
The thing to remember here is that its relatively easy to remove metal, but care must be taken, as its not so easy to replace it.