FT: Frame (Twin) Grade of Stainless Steel

[stu spalding]

Hi Herman, you should take note of the difference between ET154 and ET154/1, with apologies if I'm teaching granny to suck eggs. Cheers, Stu.

 

[vibrac]

I looked at that bolt (eg: F47/3 on M030 ) the one off my single racer is in steel not stainless its wasted in the middle to depth of thread the threaded ends are counter bored to the length of the locknut and the lock nuts were in alloy I have it loose because it was changed for a similar one with one end longer to take a bracket that carried the steering damper. Non Stainless steel is OK nothing goes rusty on a racer drinking R

 

[Herman-Handlebars]

I may be wrong but I don't think the 3/8 stud takes the loading and stress. It's the sleeve nuts ET154 that act like a dowel and engages with the headlug and head bracket that takes the load. All the 3/8 stud does is hold the sleeve nuts in place and stops them sliding out of the & head bracket & headlug.

Thanks vin998, I agree. The spares sell 2 different lengths of the ET154, but not sure as to why. But as you say the dowel section of the nut would support the stress of holding the engine to the UFM, and the stud bolt would just hold the two ends together.

 

[Herman-Handlebars]

Herman,

I think that you may have the wrong parts. You could just exchange the F47/4 for the correct F47/3. You have an early FT1/1 or 2 steering head, which needs the longer F47/3. The FT1/4, which is the later steering head is is fit to the FT3/2 that has a slot in it, so the bolt is a bit narrower. This narrow set-up uses the F47/4. I am not certain about the depth of the ET154 spigot, but I believe that ET154/1 is the long one, but I am not certain that it pairs with the long spindle.

SS is a black art in terms of selecting the proper alloy. When building racers I spend a lot of time trying to find steel parts, particularly wheel axles Regarding the spindle that is too short, for the racers, I have used a solid 1/2" grade 8 AN bolts, but you have to ream the FT3 to get the bolt through the middle.

David

Thanks David,
Yes I agree, I've asked Steve at Maughan's if there are other sizes. In my spares book it doesn't show the differences to compare so have gotten a bit lost
I naively bought them over the last 7 years not thinking if steel was the best option until now, its certainly a steep learning curve recently and I'm only just getting started with it all.
The bottom stud and nuts that I have found that I didn't buy but were from a lot of spares given to me, have slimmer nuts even though dowel part is the same length. Maybe just different from different sources
Thanks for you advice

 

[Herman-Handlebars]

It may sound like a silly question but why would you want to make this item in stainless steel in the first place?

Hi Ed, as I gave bought the parts over around 7 years, I didn't have a preference until now realizing that steel is more suitable. Would you recommend a suitable steel grade to use?
Thanks

 

[Herman-Handlebars]

Hi Herman, you should take note of the difference between ET154 and ET154/1, with apologies if I'm teaching granny to suck eggs. Cheers, Stu.

Hi Stu, no not at all. I'm very much a novice with no experience of Vincents. I've never ridden one, but just slowly trying to build one I appreciate any help I can get So far I haven't found the reason for the difference, but am working my way through my books atm

 

[Herman-Handlebars]

I looked at that bolt (eg: F47/3 on M030 ) the one off my single racer is in steel not stainless its wasted in the middle to depth of thread the threaded ends are counter bored to the length of the locknut and the lock nuts were in alloy I have it loose because it was changed for a similar one with one end longer to take a bracket that carried the steering damper. Non Stainless steel is OK nothing goes rusty on a racer drinking R

Thanks Vibrac, although I am too going to be possibly chasing Ben around on your twin (maybe being lapped is more appropriate!). I'm very much a novice, so am just wanting to get the bike the fit together nicely before looking at lightning the parts.
Some of the parts I seen whilst searching through the archives are very impressive, along with your recent sprocket carrier. I would like to do the same at some point as there seems to be a lot of benefits to it.
As you can see I have a long way to go..
Cheers

 

[Bill Thomas]

I think the longer dowel nuts are for the later head stock, Late "C" and "D" ,
Where the head stock goes inside Bracket ?.

 

[Herman-Handlebars]

I think the longer dowel nuts are for the later head stock, Late "C" and "D" ,
Where the head stock goes inside Bracket ?.

Thanks Bill, in that case mine looks like type 2 with the squares ends. As David have said, it looks like I have bought the wrong fittings for my head stock, so now I can head I the right direction. Thanks again for your advice
Cheers

 

[timetraveller]

Herman, I see you have my carb adaptors. If you are really going to race then I suggest that you go for one of the JE steering head mods as well.