Chainstay Dimpling Tool?
 

Hey!

I’ve dimpled a few chainstays for extra clearance and 650b conversions using some diy tools, but I’d like to get something a little nicer. Anyone have a dimpling tool they would sell? Would someone be interested in making one?

Seems like the c-clamp version would work best.

Thanks!
Tim

Best, if you can make it fit, is one that attaches to one jaw of a bench vise, with the "half pipe" attached to the other jaw. Attached as in bolted in where the vise jaws attach. Most vises are too bulky for this to fit into narrower stays, especially close to the BB shell. But further from the shell and/or bikes that already have more space there, it can be nice to have the rigidity of the vise. The indenter will always point directly at the center of the half pipe, so you have fewer moving parts you need to hold in alignment while squishing. This style is the clear winner for doing individual stays before building the frame.

Another decent option I've seen is indenter welded to one jaw of a vise-grip pliers, half-pipe welded to the other jaw. Been meaning to make one of those but haven't had a need for one yet.
https://cimg5.ibsrv.net/gimg/bikefor...a0b3034676.jpg

I made mine with a C-clamp, but I should have used a stronger and better-quality C-clamp. I used a generic Chinese clamp, and the threads are already feeling kinda grindy after just a few uses.

Andrew R Stewart is a regular here; he'll probably show you the one he made, which is godlike. More steel than you might want to use, but it is strong and rigid, and the design holds it in alignment while squishing.
EDIT: Ah yes here it is, scroll down to post #20

Mark B in Seattle

Wow! I’d be happy with anything really since I probably won’t end up using it all that often.

Mark, I’ll buy your old one as an incentive for you to make yourself a better one! :) Shipping to Portland would likely be affordable or maybe I can make a trip up to Seattle.

I just have such a small work space and limited tools, otherwise I’d try making my own.

Cheers,
Tim

OK, I'll sell you my old one as soon as I make a new one, some time in the next 10 years or so.

Crimping 753 chainstays - Bike Forums this is a link to a past thread that I posted my various crimping tools in. The wood block is perhaps the easiest to make with minimal tools and material costs. but it's a pain to keep the stay, the block and the form aligned while also winding down the vise jaws (in my case I already had made the block as a stay ovalizer so only had to make the steel crimping form). The solid and machined block was one of the first tools I made on my, then, new to me mill. What I thought was the final say isn't if the stays are already brazed in place, clearances for the tool's bulk are lacking. The 3 plate tool is my most recent version and the most flexible in how it is set up. I can crimp already made frames and loose stays easily. It needed no special tools to make but a saw, drill and careful laying out of dimensions. I went to a local steel house and bought the plate stock out of their scraps bin. All thread and common hardware didn't cost much too. Not shown is my attempt to make a pliers based crimper (not yet tried a C clamp one). I found a very large slip joint pliers requires too much effort to squeeze. perhaps a vise grip based one would work better.

A note about tool making- Early on I didn't have machine tools (lathe, mill) and so my self made tools were all about picking the best pre formed materials (channels, angles, strips) and dimensional adjustability (slots, large holes and would spend the time once the tool was assembled to get all it's aspects aligned WRT each other, then tighten down the fasteners to trap the alignment. This process is one I have used for a number of braze on tools, having a mill only makes the more current versions look better as the basic braze on holding aspects are much the same.

Tooling | Flickr This is a link to my Flicker album of many of my tools over the years. You'll see what I mean about non precision fabrication of the tools. Andy

The chain stay crimper I made came from an aluminum kickstand. I cut and shaped it to mimic the crimps on a Miyata 1000. When I need to use it I silicone it to one jaw in a vise. Cure for 24 hours and then crimp the stays. Have not tried it on a built frame, only unbrazed tubes. It works very well and people comment that the crimps look production. The Vise is a Wilton 4" bullet vise, about 40 or 50 years old.
Tried using a vise grip, but my hands cannot manage the leverage.

Here’s what I made with my father in law who has all the tools.
 

https://cimg9.ibsrv.net/gimg/bikefor...d8fc09c5a.jpeg
Comes with two swappable maple blocks for different tube sizes

I got a cheap small arbor press from harbor freight that I dedicated to dimpling stays. Bottom dies I made from hard wood to hold the diameter of tube I’m using and on the ram I made dies from .250” cold rolled strap and shaped and polished them till I got the desired dimple shape. This option works great but unless you do some modifications, it only works if the stay isn’t attached to the front triangle.

Welcome to the forum. Seems like it would be hard to modify an arbor press to work on an existing frame.

I had to straighten some metal stampings at work, and I superglued my dies to the arbor press. Apparently, nobody cared because it was on there for a month. It was easy enough to take off when I was done.