Custom brackets, need outside help

[D94r]

I assume you mean making the spacer the same part where the bolts go through? This would require extra wide area's around the bolts for 100% encapsulation around the spacer with the bracket. Would make for too much material and run into interference issues with the spindle mount.

[Hamstn]

bhardy501 has a great idea and I was thinking of this as a way to build it but it is hard to put into words. The only hard part is the one spacer that would need to be tapped unless you got lucky to find one with the proper ID or had enough room for a nut on the outside. Maybe mill/drill the center out to fit in a grade 8 nut that has been rounded off and then welded inside the spacer.

Use the thickest walled pipe (I have some that is 1/4" walled not sure if it is called pipe), you can find, bolt to caliper, and then cut two 1/4 pieces of plate to fit both sides of the spacers, with spacers through the plate. You only would need to go around half way if clearance was a problem. weld outside and inside of each plate where it meets the spacers then grind down the outsides to fit flush with the caliper and spindle.

Now it wounds like you are looking just to built a mockup piece to use as a guild? Just use a piece of cardboard or sheet metal and then take your measurements to enter into PC?....just add the thickness to final measurments.

[D94r]

Now it wounds like you are looking just to built a mockup piece to use as a guild? Just use a piece of cardboard or sheet metal and then take your measurements to enter into PC?....just add the thickness to final measurments.

Well, I need it to be able to support the weight of the caliper and hold it the proper distance off the rotor so I can confirm dimensions of the holes. Call it the anal retentive engineer in me

[Gadget]

I would think that 3/8ths thick steel would be as strong as 3/4" aluminum so you could use that as a blank. Then get or make 3/4" thick bosses for the bolt holes. The holes in the blank would be large enough for the bosses to fit through. Center the blank on the bosses and weld both sides. Actually, if you are only doing a mock up, 1/4 inch blank would probably be thick enough to hold things and much easier to shape.

[frijoli]

How about a water jet machine, anyone near you have one that could price doing them. They could cut bunches out of a peice of 4x8 ft. how ever thick and leave a very nice workable finish.

This is the way to go if you want multiple copies. We have used water jet cut parts over 2" thick in aluminum. The outside finish looks like a light beadblast.

Clay

---------- Post added at 05:48 AM ---------- Previous post was at 05:44 AM ----------

I would think that 3/8ths thick steel would be as strong as 3/4" aluminum so you could use that as a blank. Then get or make 3/4" thick bosses for the bolt holes. The holes in the blank would be large enough for the bosses to fit through. Center the blank on the bosses and weld both sides. Actually, if you are only doing a mock up, 1/4 inch blank would probably be thick enough to hold things and much easier to shape.

Without actually doing an analysis, we always use the double it rule for mild steel and 6061-T6 aluminum. This typically save about 30% in weight. This is a rough estimate.
Keep in mind, stuctural strength in these material is different, and if there are any safety risks involved, DO THE MATH!

Clay

[bradler451]

Looks doable they used to have a water jet machine cut things like this bracket at the local tech school pretty neat

[D94r]

Well, me and a couple guys on the Ranger forums have been discussing this, and we may be taking another approach. With all the extra modifications needed to run the 13" Cobra brakes (I haven't told you about since for now I was only focusing on the bracket) it would be much easier to run the 12" newer Ranger rotor setup.

This would only require a bracket that is much easier to design. And since there's no extra mods required (because bearings, calipers, and such haven't changed since 1995) this would seems like the better and more feasable route to go.


Oddly, it also seems (without stop-pad proof) that the 12" setup will perform better since the Ranger calipers have the same number of pistons, yet they are bigger than the Cobra's. The brake pads have more surface area, and the radial difference between the two rotors is only .5", which I don't think would show any appreciable stopping difference if all things were equal.



We'll see. Maybe I'll still pursue the Cobra bracket though as a personal objective.

[Bikespot]

These brackets can be made on a cnc mill. Doesn't matter the thickness , unless you have some powerless cnc mill. Dont have one so cant help you out there. Plasma would be an option to rough out the part. Then take a file or a grinder to finish size. Holes can be drilled once you find the right location.

I took a look at what you wrote again , those parts arnt that hard to make. Sorry i dont read every single post on here , but if you have a plasma i would rough out the part with it then just file/grind the rest. For the holes mock it up to find where you need the holes , then drill them out. It wont look anywhere as good as those parts but it will work.

[Uncle Ed]

I wonder how much heat would be transferred through that piece. The pockets machined into those bought pieces may not be there only to safe weight and look snazzy. They may be providing more surface area and air turbulence for cooling the part.

[D94r]

I think for the time being we are going to go the 12" rotor route, much simpler, but not as "cool".

As for heat through the bracket. I'd assume not much actually. On a road truck that see's daily driving there wouldn't be much heat generated. Typically you can touch the caliper after hard stops and they are warm/hot, but not enough to burn you (the rotor is a different story). So after heat transfer from the pads through the caliper I'm betting the bracket itself isn't seeing much heat at all.

Now if the truck is doing autocross or road racing that's a different story and the heat transfer would indeed heat up the brackets a lot more. But, I'd assume if the pockets were designed for that reason, he would have machined fins into it for added cooling surface area.