BIKEPGH MESSAGE BOARD ARCHIVE

@erok The one in the photo looks like something any decent machine shop could make. But what about something like this: http://www.mcmaster.com/#metal-structural-tube-clamps/=oqdvc9

If that product isn't available commercially, take a look at an outside diameter tube clamp from Ballistic Fabrication; maybe you could buy a kickstand and have it grafted onto one of them. http://www.ballisticfabrication.com/Tube-Clamps_c_219.html Also, try Googling "roll cage clamps;" that will bring up some other products that you may be able to adapt.

thanks for the tips. i was considering looking into prefab things meant for industrial uses, but didn't really know where to start.

also, the clamp has to come apart, like the handlebar clamp on a stem, because it can't slip onto the tube.

You could always sign up for some CNC classes at the techshop@BakerySQ and make your own. ;)

Oooh! I need one of these as well!

You don't need CNC. Take two blocks of aluminum, clamp together, bore a hole a little smaller than your tube. Then drill and tap four holes for the screws and whatever you need to attach the kickstand.

If you drill the hole a little undersized, as Jon suggests above, I believe you would end up pinching the tube - either upon installation or over time - and compromising (to one degree or another) the tube's structural integrity. Assuming you want to spend $60 on tools and materials to make a crude version of something you can buy over in race car world for $35 and adapt to this use, you would be better off drilling an oversized hole and carefully shimming it down to whatever fits the O.D. on the bike's tube.

Drewbacca wrote:

You could always sign up for some CNC classes at the techshop@BakerySQ and make your own. ;)

I'd suggest that the basic metal shop (covers bandsaw and drill press, among other things) class would be a better investment, but otherwise yeah. :-) Manual milling machine would make the job pretty painless, but bandsaw and drill press would work fine. If you wanna go low-tech, then hacksaw and (corded!)hand drill as Jon suggested would work, but it'll take a good bit longer. If drilling, you'll need an oversized drill bit or three, and you'll probably want to use a technique called "step drilling", wherein you start with a narrow hole and use progressively larger bits to reach the final bore diameter you're seeking. [Edited to add:] Also, unless you already have suitable bits, I'd suggest checking out prices on Silver & Deming bits and bit sets, before you get too excited about the drilling option...they're _not_ cheap.

it did occur to me that this person might have machined this themselves, was hoping that they'd see this and be like, oh yeah, found that part here and all you gotta do is do this to make it work.

If you're worried about damaging the tube there are poly pipe hangers. I'm not sure how much flex they would have, but they would be easy to drill to the proper OD size. http://www.stauffsanitary.com/block-style-hangers/anchor-base-plate-mount-hangers/polypropylene Edit: Or wheelchair parts http://www.berghspecialproducts.com/fasteners/mounting-clamps-(stauff)/mounting-clamps-(stauff)-samac/mounting-clamps-samac-no-welding-plate edit #2: Single Tube Clamp $35.00 each mid way down the page looks perfect. http://www.exhibitanddisplaytruss.com/trade_show_truss_accessories.html

See also stage lighting clamps http://www.spectrumaudio.com/global-truss-pro-clamp.html (ok I'm done)

If you don't find anything you like, you should be able to drill and through-bolt at the point I show on the sketch without affecting strength. There's almost nothing going on structurally at that location anyway. At most you would need to work up a transition piece to go from the round tube to the flat of the kickstand mount.

That's a really good point. i considered drilling thru there, but wanted to explore clamping options before puncturing the frame. also it needs to be extended toward the ground some for the most common ones to reach

sooo, funny update to this. as luck would have it, i was riding down the alley behind my house, and lo and behold, there's the bike, with the owner loading it up, a mere half block from my house. I stopped and asked her where she got that nifty piece, and said that she brought the bike and the kickstand to a machine shop (in some other city that i can't remember) who fabricated it for her. mystery solved, and there is no off the shelf help that i can find.

It was Iowa City! Good luck getting your Kona a center kickstand.

i know a few machinists who might be interested in a quick project like this.

I've got one of the root beer-generation Utes and I'd love the center stand as well. If anybody local manages to get one installed, I'd love to know where!

Somebody ought to forward this thread to Kona, perhaps there's a decent amount of people who would be interested in buying a stand for their older frames