Although I've made a few forks to date, they have all been straight blade jobbies, largely because I haven't had access to a fork blade bender. There are no locally made commercial units, so it seemed I was going to have to make one myself. So behold my hillbilly-fabulous bender.
The mandrel is an offcut from a length of redgum fencepost I found in the woodshed. I cut, sanded and planed it to a constant radius and then routed a groove down the middle. For those of you not familiar with it, redgum is a fantastically dense and hard eucalypt which proved to be just about idea for this.
The fork tip clamp was knocked up out of some steel offcuts in the scraps bin, and is anchored by a pair of M10 cap screws that are threaded into hexagonal threaded rod couplers. The wood block is grooved to match the fork tip. Note the pint-sized bottle of Little Creatures - perhaps the finest beer in my world.
At the other end of the lump of wood is the bending stop. This is another M10 bolt and rod coupler, and provides a repeatable way of raking fork blades to exactly the same point.
Doing the actual bending itself is this little doohickey. It's a short length of 25mm angle, with a bored out 1/2" nut brazed to it. The nut pivots on a 1/2" bolt that pierces the bending arm. It all looks kinda Soviet era agricultural, but damn me the thing works. Effortless, repeatable and consistent bends. Total cost was about $10 spent at the bolt shop. Everything else was already in the parts bin or was scrounged for free. I'm pretty happy with the results.
If the definition of "Simple Tools" is wide enough to encompass laser alignment, I guess my method of gauging braze penetration will be of interest. The instrument is a Nova 800 precision thickness gauge I bought second hand on Ebay. It's an echo - echo ultrasonic gauge with a facility to input the propagation velocity of the material in use. These were very expensive new but the latest Nova TG110 is now under $1000 and does everything you are likely to want. My unit was designed to work in inches but I have tweaked the display to show thickness in cm (all you have to do is multiply the propagation velocity by the appropriate factor). The transducer is quite happy with curves, I use it to measure wall thickness on tubes and stays.
The phots are of a test piece - two strips of approx 1.1 mm 316 stainless sheet silver brazed from one end. In phot 1 the transducer is over the brazed section so it shows a thickness of 2.35 mm; in phot 2 it's over the unbrazed section so it only shows the thickness of the top strip.
I'm gonna bump this hard; I'm sure there's more out there to share. The homemade fixtures are just the best.
I'd contribute if I had anything of real value to add (look! angle steel AND a three-way c-clamp!)
When it's time to change hole saw arbors for a long cut... I curse those little buggers. So I used some "strategery" and made this little lever arm. Threaded on one end to accept a knob, and a filed groove to locate into place at the hole:
My brake post jig. I have a collection of arms that are drilled for various post locations and make new ones as needed. For forks the Vee block thingie goes under the dummy axle, for posts on the rear end it goes above.image.jpg
I have noticed a lot of fatigue and cramping in my hands when filing fillets. A large part of this is the result of lousy handles. I needed something more ergonomic and ball shaped. I aquired some walnut and turned these.
This thing was meant to be a lug vice. I think I've used it once for that - I don't do much with lugs - but it's damn handy for other things, like pushing out this big dent in a head tube:
I made this little ditty today by welding some threaded bits concentric with each other in a v-block. Thread the DT shifter bosses until they snap onto the DT and the bent rod acts like a spring keeping everything where it should be. I was going to mill something out of scrap aluminum and reeled myself back by checking this thread. The simplest solution FTW.
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