Stainless steel

General purpose topics/chat goes in here
Member
Posts: 52
Joined: Wed Dec 16, 2015 1:50 am
Location: Valais-Switzerland

Stainless steel

Postby JDFS79 » Tue Jun 25, 2019 7:38 am

Hi , I was wondering if it's possible to use stainless steel tubes in order to make front fork inner tubes?
The reason I ask is because I work in a factory that fabricates stainless steel tubes ( 304 , 316L, 316Sl 904 , etc) all kinds of diameters and thickness, and I could get a couple of pairs to try to do the fork stanchions ( doesn't look to difficult to make) . I can get the tubes polished to a maximum grit of "1000 or scotchbrite". I didn't do this already because I don't know if it's a good material to use as a fork.
Appreciate all replies. Daniel

Member
User avatar
Posts: 304
Joined: Sun Mar 18, 2018 12:02 pm
Location: Bristol UK

Re: Stainless steel

Postby Martin.S » Tue Jun 25, 2019 8:23 am

Mmmmm - there's lots of people out there who shun using stainless for fasteners in the slightest of stress situation let alone in an area as important and highly stressed as the fork stanchions.
Stainless I understand is more susceptible to work hardening and fracturing under stress. I don't mind using stainless in a stressed area if I think the part is large enough to cope but fork stanchions that are designed to be able to flex - no I wouldn't myself.
Cheers

Member
Posts: 6095
Joined: Wed Sep 01, 2004 12:00 am
Location: WEST SUSSEX UK

Re: Stainless steel

Postby SPRIDDLER » Tue Jun 25, 2019 10:38 am

That's a very thoughtful initiative, Daniel, as I understand that the club spares scheme is constantly on the lookout for new suppliers as current ones retire or costs become prohibitive.
I'm not qualified to comment on the suitability of s/steel but I haven't found the current stanchion material to be particularly unsuitable, although there are certainly occasions when collision damage or corrosion due to water ingress necessitate replacement.
However, and I don't want to dismiss your suggestion, I think much of it comes down to cost in view of realtively low volumes. The club currently sells them at £80 a pair which at a wild guess probably means a purchase price of perhaps around £60 a pair, (delivered to Kettering).
Perhaps the spares scheme has an opportunity for other components?
I poke badgers with spoons.

Member
Posts: 52
Joined: Wed Dec 16, 2015 1:50 am
Location: Valais-Switzerland

Re: Stainless steel

Postby JDFS79 » Tue Jun 25, 2019 5:13 pm

Well I can get the material for free and cut to the correct length, and do the polishing, but for the thread in top of tube or the groove for the circlip in the bottom , I don't have the tools nor the skills for that . If someone could tell me that for example the 304 S. Steel material matches the specifications of the steel used to make the forks, I'm saying this because I made an order to a client last week with that quality ! The tube as 29mm exterior and 2.5 mm thickness (1.4401) similar to the 1 1/8 fork tubes, well a little bigger but I can grind it to near 28.5 mmm losing also some thickness naturally. I can also check shipping costs to the UK , and if someone could do the final job I will be glad to ship it .

Member
Posts: 434
Joined: Thu Mar 31, 2005 12:00 am
Location: BERKS UK

Re: Stainless steel

Postby Andy51 » Tue Jun 25, 2019 8:38 pm

I do not believe that the commonly available stainless steels are suitable for stressed parts. Axles, girder spindles, etc, are made from EN16 or 24. I understand there are stainless equivalents but they are very rare (and expensive!). Andrew Engineering used to sell 'hi spec' steel stanchions but I do not know what material they were made of. Remember the 1 1/4 stanchions were introduced as the 1 1/8 were marginal for the job as bikes got bigger and faster, so making these in anything of lesser spec than original would really be pushing it. Andy

Member
Posts: 6095
Joined: Wed Sep 01, 2004 12:00 am
Location: WEST SUSSEX UK

Re: Stainless steel

Postby SPRIDDLER » Wed Jun 26, 2019 8:30 am

JDFS79 wrote: .....if someone could do the final job I will be glad to ship it .

Nice idea, Daniel, and I can't speak for our spares people but I would think that getting them finished locally (assuming that using s/steel is necessary, suitable and cost-effective) is not a simple or practical option. In addition it would also put the club at risk of litigation in the event of failure (for whatever reason) of this safety critical item from two separate (arguing?) fabricators.
I poke badgers with spoons.

Member
Posts: 52
Joined: Wed Dec 16, 2015 1:50 am
Location: Valais-Switzerland

Re: Stainless steel

Postby JDFS79 » Wed Jun 26, 2019 10:21 am

I understand that Spriddler, I only suggest S/steel because I work with that material and I can get it for free . Mine stanchions on the G3ls are really bad and they are not easy to find at a good price.
"AJS/Matchless 1 1/8" Fork Stanchions
(Hi-Tensile)
1 1/8" -28.5mm
Length: 23 5/8" -596mm
1941-47 and 1951-54"
These are sold at British only Austria for 299€ !!!!!

Member
Posts: 2941
Joined: Sun Jan 01, 1995 12:00 am
Location: ESSEX UK

Re: Stainless steel

Postby G15 Roy » Wed Jun 26, 2019 2:50 pm

Just to keep you all updated i have emailed Daniel and we are going to get a pair sent to the Club to be checked out and see it they will be suitable.
Roy

Member
User avatar
Posts: 736
Joined: Mon May 01, 2017 6:32 pm
Location: Lancashire

Re: Stainless steel

Postby spookefoote1956 » Wed Jun 26, 2019 4:42 pm

Free stainless you say? Hmm.................................... Has anyone ever told you how handsome you are? :D
हरे कृष्ण हरे कृष्ण
Hail Joe Lucas ............ Prince of Darkness!
All my bikes are original........ to me!

Return to General Topics

Who is online

Users browsing this forum: No registered users and 17 guests