Sometimes things do not behave as expected…!

 A while ago, I was preparing a prototype for a new project, it required manufacturing of several components through laser sintering , which i subcontracted to a rapid prototype service.

I designed some splined pulleys for a timing belt , the key components of the entire project, and we all know laser sintered prototypes are accurate enough to make such a thing work right?...WRONG!!!

 Timing belts require very accurate pulleys with perfectly formed teeth, so when i tried to match the belt with the pulley i realized that the mechanism simply did not turn!

 A rapid evaluation of the situation told me that i was on the edge of a total failure, the customer had to present the prototype at a trade fair the next week, there was no time left for making new pulleys.

I really do not know how this idea came out, but I had no choice but trying…

I cut a die on the wire edm with the same profile of a working pulley and used it for extruding the prototyped pieces.

 wire edm cut emergency die

It worked better than expected.

the prototype was delivered in time and behaved very well.

A lesson learned?

you bet!!!

extruding the splined pulley!!!