[dohcfiend]

i was thinking that too. $100+!?!. didn't get a whole estimate but for now based on some other numbers above i will say around $250-$300 would be a closer ballpark. it is high for my taste for the moment, but at least there is something available if i feel the urge.

but.... now that i have something to go off of for a comparison, i can perhaps talk to some larger companies and see what their estimates are vs d.o.h.c.'s estimate.

unfortunately, i have some other projects going on for the moment, so this will have to wait until something get's completed.

things usually do cost more for a 1st time R&D run. i know for certain that i could probably beat that price but the would the amount i save be worth my time spent finding it?

that leaves me with my last question for the moment. if i do pay for a single run for myself, do i get the cad files and stuff needed to cnc the bushings?

[CNCguy]

Poly bushings are usually made in a molding process. The issue is, someone has to invest in having a mold made. Over time you have to recover the cost of the mold. The cost of poly bushings can be pretty cheap depending on the mold. The more cavities that a mold has, the cheaper the production costs are. I have some poly bushings made in a four cavity compression mold and my cost is $8 per bushing. The same part from a single cavity mold would probably cost around $20 each. A molding machine with a single cavity mold has to be cycled four times to get the same production as one with a four cavity mold. Of course, the price of the mold increases as you add more cavities.

Poly bushings also need to be greased regularly. Poly is a step up from rubber but materials like teflon impregnated nylon offer less flex. Nylon has its drawbacks as it requires a perfect axis of rotation or it will bind. Heim joints are the ultimate connection as they provide almost zero flex and can rotate easily on a misaligned axis.

Chassis Engineering by Herb Adams offers some good info on this and many other topics.

[Juglenaut]

Can the right CNC machine cut poly?

[CNCguy]

Originally Posted by Juglenaut

Can the right CNC machine cut poly?

You can machine harder (80+ durometer) poly with extremely sharp cutting tools. Softer materials need to be frozen first using something like liquid nitrogen.

[dohcfiend]

oh, it's molded? well damn.

[d.o.h.c]

[d.o.h.c]

[d.o.h.c]

Lowering price to 40 shipped.