Custom brackets, need outside help

[D94r]

This thread is geard more towards Gadget since I know he has a functional CNC plasma table. But I'm making this public as I'll take all advice/help from anyone.


What I need is custom brackets made that will adapt a Mustang Cobra caliper onto the Ford Ranger spindle. It's a very simple bracket and design with no depth offsets for any of the holes. This bracket allows us Ranger guys to go from the measly 10.5"/11.28" rotor to the massive 13" Cobra rotors up front for improved braking.

Soooo, what I'm wondering is, if I can get the dimensions of these brackets along with creating a dimensional file of them for whatever software is used, can I get someone to cut me out a couple for mock-up on my truck (Gadget ? )?

These brackets are produced by a "company" in Canada, but their prices have gone through the roof since they started makeing them and have almost doubled in price, which is outrageous for what they are.

Of course I'd pay for the metal stock and your time (to a point, trying to keep this cheaper than the "company") for the one-off's for R&D. Then, if the test fitment is good cut you (whoever is willing) in on the production of these brackets.

I come on here asking you hobbiest in the hopes of finding a cheaper initial solution to getting some one-off's made instead for R&D instead of a local shop charging full shop rates (and there are no hobbiest local that I can find).

Since these are a uniform thickness (which I'd have to measure and determine) I don't know if it would be easier for a CNC mill or CNC plasma to cut out (I guess thickness and plasma cutter capability would be the key determining factor). The other company makes them of aluminum, but I would think steel could be substituted without any problems since the factory spindles are cast (iron or steel I'm not sure of though), so strength shouldn't be a problem.

Anyhow, to give you guys an idea of what needs to be made and the end goal for these brackets here are some pics.

If anyone is indeed interested in helping out, more finite details can be hashed out in PM.




Brackets themselves. The inner milled out material is not neccesary, its an aesthetic point to the brackets.



Bracket mounted to the Ranger spindle.






Bracket mounted to Ranger spindle, with Cobra caliper bracket mounted to bracket.



What we start with and what we end with for a comparison of final goal.

[BearNPum]

It is going to take a pretty decent plasma cutter (as in amps) to cut steel that thick cleanly. I don't think the plasma cut is going to come out very clean in comparison. Would be worth a try though if someone wants to attempt it. Wish I had a CNC machining center to help you out.

[D94r]

Yah, that's my worry too. I'd have to mock up a few things to get a measurement, but I'm guessing the bracket is around 5/8" thick. I have a buddy across the country who has a laser cutter at work who I've contacted about possibly helping out as well.

Push come to shove I can use the 4" grinder to cut out the rough shape of these brackets, then round out the corners carefully. But good lord that would take a lot of patience and make a hell of a mess.

[Hamstn]

A lot of the cost in making those as pictured is for the "bling" factor. For doing that on the cheap I would go with a piece of 1/4" steel. Cut it out with plasma or O/A , smooth out, tap the holes (hard to see if they are or not), then if needed at the caliper bracket cut spacers or add washers to get your 5/8" spacing. Maybe better yet but a bit harder is 1/2" steel which would be near enough to 5/8" for your spacing. Steel would be stronger then the AL but much heavier.

Another idea would be to use AL but cut it out with a jig saw and drill holes with a press. Take some time and not be as pretty, but?

[D94r]

Yah, I totally realize that a lot of the cost is for the "bling". The guy needs to make a profit, but he's gone astronomical on the prices (these brackets are part of a kit, but still for what you get in the kit it's way overpriced).

The one hole is tapped, the rest are pass through.

I'm not too keen on the washer as a spacer idea, but I have tossed around the idea of making steel standoffs and welding to the bracket to get the proper width. Ideally though I'd rather this be one solid piece.

I have plenty of time to formulate a solution, so we'll see what goes down.




On further research into these brackets, it turns out they are 3/4" thick. That is going to take one hell of a plasma to cleanly cut that. I know my LP50 is rated for 3/4", I just dont have a steady enough hand for perfect perpendicular cuts through the metal, nor a CNC table.

[BearNPum]

If you didn't mind it being a bit rough, and could drill the holes yourself, I think a CNC like Gadget's would have a shot at getting a rough blank that would be usable. Hamstn's idea of 2 thinner plates with spacers is a good plan as well.

Depending on how nutty they have gone with the price, you may be able to have a local machine shop do these for less money.

[Gadget]

I think the thickness is going to be critical since the bracket has to hang centered on the rotors so that can't change. 3/4" thick steel is thicker than anything I have cut on my CNC, 1/4" has been the max so far. I suspect you will get some beveling of the cut on a piece that thick. I certainly wouldn't try to cut the bolt holes with the plasma. You also won't want to pierce cut this piece either, 3/4" pierce is a lot to ask. You would have to start at the edge and cut into the piece from there.
And then we get to the biggest issue to me, that of liability for producing a part so critical to the safety of a vehicle. I probably could rough cut one but don't think I want to put myself at risk for the liability that might create. Part of the cost of the commercial units is for liability insurance I'm sure, and justifiably so.
As purely a hobbiest, I will have to pass on this the potential liability is too great for me.
Sorry,
Dan

[bhardy501]

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.

[D94r]

If you didn't mind it being a bit rough, and could drill the holes yourself, I think a CNC like Gadget's would have a shot at getting a rough blank that would be usable. Hamstn's idea of 2 thinner plates with spacers is a good plan as well.

Depending on how nutty they have gone with the price, you may be able to have a local machine shop do these for less money.

You know, I didn't read Hamstn's idea as "two thinner plates with spacers", but now that you put it that way, two 1/4" pieces sandwiching a 1/4 spacer, then all welded could indeed work.... my only concern would be welding of the inner side of the spacers to the plates. This could be done if the center of the bracket was cut out on atleast one of the brackets though.

I think the thickness is going to be critical since the bracket has to hang centered on the rotors so that can't change. 3/4" thick steel is thicker than anything I have cut on my CNC, 1/4" has been the max so far. I suspect you will get some beveling of the cut on a piece that thick. I certainly wouldn't try to cut the bolt holes with the plasma. You also won't want to pierce cut this piece either, 3/4" pierce is a lot to ask. You would have to start at the edge and cut into the piece from there.
And then we get to the biggest issue to me, that of liability for producing a part so critical to the safety of a vehicle. I probably could rough cut one but don't think I want to put myself at risk for the liability that might create. Part of the cost of the commercial units is for liability insurance I'm sure, and justifiably so.
As purely a hobbiest, I will have to pass on this the potential liability is too great for me.
Sorry,
Dan

Yes, I feared beveled cuts too for material this thick.

Holes would not need to be cut, just the outside edges of the bracket itself. Holes would be drilled by me in a press.

As for liability I totally understand. But really what I'm wanting right now is just a mock up piece that wouldn't be used for anything else. A final piece would be copied from that for actual road use. This would be purely for mock up to make sure all the critical dimensions are correct.

FWI, the guy produces these on the side, so liability insurance isn't a factor at all through him.

Besides, you'd only be cutting out a rough shape in metal. What someone uses that peice of metal for is their own business... right?


Anyhow, I might give the 1/4" plate + 1/4" spacer + 1/4" plate a try for the mockup piece. That would make it the appropriate thickness and I'd only have to use a peice of 1/4" stock.

My buddy said if I can get him a CAD drawing of the peice he can laser cut it too for the final product. I just need to make the initial bracket, then measure and draw it out in CAD.

[bhardy501]

Another idea would be to make 2 1/4 plates and a 3/4 in spacer. drill your plates out so the spacer would dropp all the way through. bevel the inside of the holes so you can weld them up from the out side and not have to worry about trying to weld on the inside. You would have to build a jig to hold them for welding.