I have started fabricating a custom frame to house the STi Group N hydraulic handbrake cylinder. I have used some 50 × 50 × 3mm steel box tube. I chose this heavy steel because I want it strong. (and if i went any thinner, id blow holes with the welder)
I have welded it into an 'L' shape. Boxed in the ends. Then cut access slots and weight saving slots into the frame. Im really happy with it so far. And my welding is getting better all the time. I actually managed to weld up the ends with 100% water tight seams. Not bad for no formal training and using a super cheap stick welder.
I have ordered some new Ultra High Performance rod ends from McGill motorsport in the UK. (These are the same high quality bearings i used on my custom swaybar links.) I am going to replace both cylinder rod ends, and also use double spherical metal bearings on the main lever pivot. All the moving parts of this mechanism will be steel sperical jointed. Because i want it smooth, tight and with NO slop, and i want it tough, unlike the old twin cylinder frame.
I tried to replicate the lever ratio and handle throw as best i could from the original STi handle mechanism I got with the kit from Nauli / Steve. A bit hard though as i never got to see or feel it when it was plumbed in. But even if I am out with my calculations. I have built multiple adjustments into the design. Once built, I can easily adjust the lever ratio, handle angle, cylinder mounting length/depth. So i am sure it can be set up easy enough. The adjustments come by way of the threaded rod ends i am using and multiple pivot mounting points etc. Too hard to explain, you'll just have to wait untill the parts are here to see it.
Unfortuantly, I dont think I will be able to use the lever Russ made me. But I may have a family friend contact who has a laser cutting buisness in Henderson. So Im hoping I can negotiate a custom lever for the mechanism. I will make it still interchangeable with the APS twin style of handle mount. So that way when my custom CNCd handle is ready, it will bolt straight on.
The main lever pivot bearings will be housed inside the small end of the 'L' The end of the cylinder will be mounted against the end section of the long part of the 'L' The lever will connect to the cylinder in the corner of the 'L'
Heres some progress pics.
