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Cheers guys, PM on the way! Excuse me if the question is stupid, but how does one work out the angles of the brake mount holes in respect to the dropout from the above drawings? Was hoping a simple unique jig for front and rear is possible (like this http://forums.mtbr.com/frame-building/kickstarter-project-iso-disc-tab-mounting-fixtures-950617.html).
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You dont really need the angles. If you draw a triangle (axle <-> first bolt hole <-> second bolt hole) where the sides are the right length it will fit.
Probably cryptic explanation: (look at front drawing)
For the front:
First draw 2 circles with the same center: radius 87,32mm and radius 49,74mm
then pick any spot on inner circle (= first bolt hole) to use as center and draw a circle with radius 51mm.
Where this crosses the outer circle = second bolt hole
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You can use a disc brake caliper and mount it on the tab you want to weld to the frame.
Make sure you have the right clearance on the rotor. Then tighten the lever and use tape or similar to keep pressure on the rotor. Then you tag the disc tab onto the frame, remove the wheel and brake caliper and finish welding everything. That would be the cowboy method.. -
@svendhöek got it, thanks! @Hulsroy, was thinking that the cowboy method has to be possible as well and then saw other people mentioning it online, so was thinking of doing that as well, it would just mean that I need to buy the wheels and brakes before I have the tabs in place (sucks if the projects turns to sh**!). I guess most of the tabs will need some adjustments (cutting, filing) before being welded in place?
svenhöek
Hulsroy-
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ISO Disc brake jig measurements
Posted by
@FredyCro
I am planning on getting ISO disc brake tabs welded/brazed on my daily commuter (rigid MTB) and if this proves doable converting a steel road frame to disc brakes as well. I thought of ordering 808N and V4 disc brake mounts from framebuilding.com (http://www.framebuilding.com/what.htm) and getting them professionaly TIG welded or brazed back home in Croatia where the whole thing wouldn't cost much.
Does anyone know where I can find exact measurements for placing of the front and rear tab? Or alternatively has a jig drawing and is willing to share it, @Hulsroy maybe? My girlfriend, who studied architecture could draw a jig and hopefully a friend of mine could machine in it the uni.