I think the prices for Pettit's and Unobtanium's are just ridiculous. They seem very simple to make out of some polyurethane stock. Anyone ever done it at home? Is there some complexity i am missing?

There has to be soem reason peopel are paying $160 for two cylinderical pieces of plastic with metal centers.

 

i would like to know too!! i know jimlab makes them but only in group buy's and its never the right time for me!!

 

Probably because most people don't own a lathe or have the slightest idea how difficult it is to machine anything...

BTW, my differential bushings are and always have been $90/pair when available. Price the Mazdaspeed "40% stiffer" rubber differential bushings or Mazda OEM differential bushings and then get back to me on how ridiculously expensive mine are.

 

would making them out of aluminum be a bad idea. i have made aluminum moter mounts.

 

They'd just transfer even more noise. If you can live with that, aluminum would work just fine.

 

aluminum is extremely easy to machine. I agree most people don't have onebut a machine shop could probably make them extremely cheap since very little machine work is needed. I didn't know your's were priced at $90, is that only during group buys or on an individual basis?

 

You don't have any experience with machining parts, do you.

Only during group buys, since I don't carry any extras in "inventory" these days.

 

no milling experience but as far as turning aluminum on a lathe yes. I could turn true bushings in 9th grade metal shop!

I'm not ragging on your product, as I'll probably be getting some soon, I'm just trying to understand the extreme cost of the bushings. Your material costs cannot be that high and as far as the machine work goes... do you hand turn each piece or use a CNC machine? I understand R&R and S vs. D but come on.

I mean I'm glad soemone is doing it or we would be without, and if I'm being ignorant to some extra cost then please let me know.

 

Good. Do you remember how long it took you to make one?

Even something as simple as a bushing takes time to make, and the number of cuts and precision of the tolerances increase that time, especially if your machinery isn't computer controlled. Even if you have access to CNC machines, you still have to develop the G-code (or design the part in a CAD program and have it generate the code) to make the part and test it to make sure you got it right. Making multiple identical parts at the same time eliminates the setup required for each subsequent part, but they parts don't make themselves. Even with CNC, someone has to do the setup and load materials and remove finished parts from the machine, and they're likely charging at an hourly rate.

Multiply the hours it took to make a part by $50-60 (average shop rate) and by the number of parts, and you'll figure out that even taking your pre-designed part to a machine shop can add up quickly. On average, machining is 90% setup, 10% cutting. Materials are maybe a third or less of the cost. The rest is incurred by labor and setup.

You seem to be assuming that labor is free and that bushings almost fall off the lathe ready-made in under 10 minutes, but other than that...

 

these are not intricate pieces, the tolerances aren't even that tight

but hey, you could be charging Mazda prices I guess. I just wish there was more competition in our aftermarket (for certain pieces). I guess The Fast and the Furious only helped out the resale of the Supra!



BTW: why don't you make motor mounts, pretty open market there.

 

double post

 

Whatever. You're more than welcome to make your own.

 

I made a set. I used the housing as the mold. I used 94 shore urethane. I then drilled the center, used a brass center sleeve and installed them. I also placed a soft urethane liner around the center sleeve to soften the initial feel. I don't feel any extra vibration. The cost was under $40.00. I also stiffened a mount on my Riviera with the left over.

 

In materials, I assume. What do you value your time at and how much of it did you use?

 

where did you get your urethane if you don't mind me asking?