New forum - Frame Builders

@coldharbour @danstuff @hoops @Skant @Hulsroy Could you guys help me identify the tubing above? Any help would be appreciated.

Edit: it’s Oria GM 0.0

Replied on another thread but looks like the Oria Tubing on my Moser.

Is there a more appropriate thread for a recommendation for frame alterations in the Midlands?

thread dredge, but yes BikeCad is astonishing value..... around 300 Canadian Dollars for eternal support, or until the guy dies or something..... Really worth it for a builder or fitter to take the time to learn to use it, very useful to be able to "mess with " the dimensions and see what it does to the fit, also a great tool for explaining why some bike JUST WON'T fit some riders.....what I do is draw the rider's current set up onto a given bike, and show the 140mm 45' stem required to get the bars to the right position, or imaginary 45mm layback seatpost etc etc

Pretty sure we had some tange tube

Anyone on 'ere that can either extend threads of a fork steerer or cut down and rebraze the steerer so its shorter? Got an argos aero fork I want to finally sort out in the near future.

Had that very job done at sbc cycles for a very reasonable price

How much is reasonable?

Was some time ago but was £15-20 iirc..

Not quite sure the place is the right one to ask, but i'll try my luck.
I have a frameset that have a clamp of the seatpost that probably not the most robust design:

There is a screw at the end of the top tube that lock the seatpost in place.
A closer look:

I was afraid to overtighten it, and at the end of a ride it slipped and the seatpost went down the seat tube (hopefully, it was at the end of the ride near my place). I re-set the height and tighten the screw quite a bit more, and it hasn't moved since (but I've not rode it much).

Is there any solution to this? I have a framebuilding company not far, so I'll probably ask them but as it is on appointment only and with a 45mn drive, I reckoned it was interesting to ask on here before.

What would be the potential solutions to have a better seatpost holding solution?
Change the complete seat tube (but would be a pain I believe since it go through the top tube)?
Manufacture a seatpost with an expander (like a stem)?
Buy a steel seatpost (if that's even a thing), tighten the screw hard and not worry about it?

Thanks in advance for any ideas!

That's such a cool frame! Ive not seen a clamp like that before. Does the screw tighten directly onto the seat post?

Yes indeed, that is why I was a bit worried as the screw is "pinching" (not sure the term is correct, I think it would be a grub screw in english) directly the seatpost, I didn't want to destroy the seatpost (it leaves quite some marks as the seatpost is in aluminium and the screw in steel). Therefore the idea would be to have a less destructive design haha
This clamp design was vastly used here in France on MBK frames ; the one I have was a specific paintjob for a pro team back in the 90's (MBK Vetta or Chazal, can't remember exactly and I'm no expert) I've just changed the fork for a straight one
EDIT: base model name for this design was "MBK Mirage", and it has funny aspects like the top tube that changes shape towards seat tube.
With OG fork it kind of looked like that (in less better conditions)

wow thats strange, that would really mangle a seatpost. I guess you could get your framebuilder to slot the st/tt thing, then braze a threaded post in there then it would basically just be like a normal frame. But that would damage the paint

I guess the only other thing i can think of is use a smaller seat post, and make a shim that supports it in the seat tube and has some relieved panel that the bolt can put pressure on.

like this

1 Attachment

Yes that is a completely stupid design IMO as it is "destructive" but it is like it is.
Hmm interesting idea, post is 26.0 so maybe with a 25.4 seatpost, that leaves room for a shim of 0.3mm thickness.
Maybe even a stem shim (as 25.4 to 26 is quite common for stem/bars) could work to reinforce? Since the shim is already split in two parts that plays the role of the relief panel maybe?

Obviously having the frame modified would be much neater and much more robust (despite the paint destroy), I would prefer that, but I can't see how the framebuilder could slot the seattube and add a thread clamp thing considering the low amount of seat tube protruding of the top tube, Or maybe by adding a sleeve within that protrude higher and then do the slot/clamp thing?

You could put the punch bolt below the toptube. There were some bmx frames (and probably road and mountain frames too) like this.

I’ll see if I can find a pic.

Not quite the one I was thinking of but same concept

The one I was thinking of had the slot/binder on the front of the seattube. That’d be how I’d choose to do it if I was doing it as it’d keep the crud out.

Nate Zukas does this

https://www.instagram.com/p/Bz9XQzrlI0g/?igshid=1ecmvqmx2egrh

Hmmm I see didn't think of that one, that could be quite neat and that's a great idea! I'll see if I can propose to framebuilding company or see what they suggest. Thanks!

Thought I'd ask here if this wizardry actually works?
https://www.yocartgo.com/products/solution-welding-flux-cored-rods?variant=31684605444186

It probably does the thing they say it does, but im not sure it massively sturdy. Its not a very clear site, what are they selling?
Theres a photo of a guy welding, as well as a soldered copper pipe joint and they talk about aluminium so idk.

As I understand it (there was a video ad on Instagram...), it's somekind of flux that with very little heat is supposed to or more less work like metal glue. I think my real question is if something that has a very low melting point can have a high tensile strength?

https://www.youtube.com/watch?v=WMxBaq13UO4

inside waltly ti, "cheap" ti straight from china. might be interesting to some

Hello,

Can anyone send me a 3d model of a pinion gearbox?

Kind Regards,

jim

Proper argy bargy on mtbr framebuilding thread. PVD pile on. He had it coming. Get the popcorn out and give it a read