Framebuildin' part 3

I’d say ISO but I haven’t done any disc bikes. Easy to make your own mounts out of plate and wouldn’t be that hard to make a little jig to go on a dummy axle if you have machine tool access.

Paragon sells iso mounts for like $4

The Paragon mounts are hard to beat.

I like the paragon lowrider drops. They cost a lot more than tabs but they are neat.

This one is still glassy in the photos. I think I’ll soak/ brush it and run it as is (unfiled/ "maker’s mark).

Done a little Google, but wondering if any of you guys have an easy way to fixture ISO dick brake tabs. Should I consider making something out of aluminum to act as a heat sink? I’d prefer to make something from steel plate because free.

I used the paragon lowrider mounts because it was cheaper than worrying about tabs and a fixture.

The Anvil tab tools are pretty sweet and not a ton of money. If you’ve got more time than scratch you can definitely make something. Look up with Shimano specs and replicate. If you go the dummy axle route, be sure to not just index off of one drop out- go ahead for a full length axle. If you are not using an integrated tab you might as well make sure both drop outs are aligned before adding the tab.

I just cut a little boomerang out of 3/16" steel sheet, drilled a hole in one end the size for a threaded axle, and two other holes in the right place for mounting bolts. I have two spacers that space the mount out to the right location relative the axle locknut. Doesn’t take much.

If you just need to do one, you could use a parts bin disc hub and an old mechanical disk brake to clamp the mount in about the right place.

[quote=drwelby]

If you just need to do one, you could use a parts bin disc hub and an old mechanical disk brake to clamp the mount in about the right place.[/quote]

I have all of those things.

i had an idea for fender mounting

fender can be r/r without taking the wheel out, fender line can be baked in at end of build allowing for variance in tube bending

Talk me into or out of 3d printing dropouts ( with this stuff: https://www.shapeways.com/materials/steel )

I like that. Pair with some carbon fenders.

It also looks like you could thread a normal u-shaped stay through that. Maybe some rubber grommets in there to keep things tight.

Whats the logic behind the offset hole? Seems like it would make drilling a pain and give an uneven surface for mounting.

Design direction seems valid. I note this in the material description: “This material is 3D printed 420 Stainless Steel infused with bronze, and has a final composition of approximately 60% steel and 40% bronze” - not sure if this applies to all their ‘steel’ material, ie if it’s not actually stainless that might have implications for how it’s brazed or welded to a frame.

yeah the lateral asymmetry of the fender rivets is kindof a pain, and then the rack boss side being offset too

check out gopro mounts for a standardized way of doing this

[quote=crowding]fender can be r/r without taking the wheel out, fender line can be baked in at end of build allowing for variance in tube bending

[/quote]

Not attaching the fender directly to the fork crown makes a lot of things way easier

My setup has tangent bosses on the rack at 11 & 1 o’clock with no daruma, making it much easier to remove or pivot out of the way of a wheel tray. It also let me make the fork longer without worrying about the fenderline, so my rack platform could attach to the crown without bending down to meet it.

When my fender flexes it does stack up into the fork crown a little so I see the benefit of having your boss behind the crown on the reacharound, but the rack sandwich at the crown seems kinda absurd

those mounts look similar to the MAP/soma light mount

The flat mating surface is on the bike centerplane, which should make a good setup reference. The rivets are placed symetrically on a diagonal around the bolt hole. That might have come from watching skateboard youtube and noticing how how they put trucks on with 2 diagonal bolts. My thought was that it would better damp both lateral and vertical vibration modes. A gopro style interface might be more visually parseable + better at resisting unscrewing though

Fork crown sandwich is my continuing fetishization of transmitting steering torque to the rack from the fork crown, but not using side-of-crown bosses as there will never be standard placement for those. It does look a bit overkill.

edit: the rest of the bike in silico

compared to Homer v1.0 it’s a size smaller, 30mm shorter chainstays, moar front center, slacker angles and 13mm lower BB. Targeted 584x57 tires but will run 622x42 until I build some 584 wheels

I’m contemplating doing printed faux-loop-stay styled plug dropouts in back with a straight blade unicrown fork in front, would be more unified aesthetically


map/soma/tanaka

It doesn’t list it’s actual strength. Part of me says make it pretty thick and you’ll be fine.
but how would it take brazzage?
will it just crack and fall apart?

edit: regarding 3d printed dropouts