John Rygg

on the original button I think the legs were there to flex .. but they are also so brittle that they break.
the new plastic they are printed from at shapeways has more flex in it so I think this design will work.

it is worth a try , if not I will reinforce the legs from the sides to allow more flex.

we will see ...

MrRoboto

I will wait for the updated design and defrost button before I place my order. Just to confirm, the button will no longer light up at night, correct?

John Rygg

Right now I have 2 type of buttons . one with a raised design that can be painted white this will not light up.
and the other one is a cut out design that will let the light pass through.

the updated design should be printed out and sent to me in about 1 1/2 weeks.
I will post it here once it has arrived.

Thanks for everyones help on this one .. hopefully we can have a very low cost fix for the button problem ... and I don't even have a 993

MrRoboto

I'd prefer the cut-out design. Can't wait to put my order in. BTW, you're awesome.

Grapeape

How about printing these little bastards. It looks as if it's laughing at me for resetting my odometer while moving, worked fine until I reset. Currently at $50 for the set, print away and sell at half the price.

John Rygg

That would be a good one to do .. I have a broken gear in my odometer also .. not sure if it is the same as the 993 one . If you want to send me your broken one , I can try and model them and print them in Nylon which would be much stronger.

Grapeape

My new gears are in the mail and I hope to have the speedo reassembled and back in service this week-end. If you want to give it a go PM your address and I will mail the old gears to you. If you can print successfully maybe future RL members that want to tackle this dyi will benefit by saving a few bucks. I'm not schooled in manufacturing costs but $50 for nylon gears about the size of a dime seems excessive which may be due to the fact that they're the only game in town.

John Rygg

PM sent

John Rygg

another interesting idea for the gear. I could print it in nylon which is very strong . or it could be sent off to shapeways for professionally printing in metal .. it would last much longer I would think

phoneyman

What infill % would you use with the nylon? I couldn't see much stress being on the gear, but maybe I have no idea. I print using PLA and you would need a big hammer to break any pieces printed correctly, not factoring in fatigue.

John Rygg

The gear is quite small, so I do not think infill % will make much of a difference . I usually print 3-4 solid outer and top/bottom layers. with a print this small it will be fairly solid anyway.
but I would print it with a high % of infill . it is small and limiting the infill would not save much.

the original gear fails quite often due to fatigue so I would want to make it as strong as possible.
PLA prints great and is very strong , but the high temps in the cabin during the summer can cause the PLA to warp. Nylon has a higher softening temp and would last longer.
what kind of printer do you have Phoneyman ?

phoneyman

That makes sense, I've never seen the gear in question before. I have a makerbot 2. Started off with a homemade prusa but I never got it to work correctly.

The only prints I've ever cycled were for my old job. I used PLA with 2 shell layers and 30% infill and printed artificial heart valves. The fixtures had about 2psi applied radially outward and were cycled up and down @ 20Hz in 99*F water for 100M cycles. Not much load but they held up great and maintained their shape in the heat to within 1%. Just fyi about that material.

I agree about making the gear as strong as possible. Which printer uses nylon? I haven't kept up on printers, I've only seen PLA and ABS. Thanks for this thread and your work, btw.

John Rygg

Sounds like you have done some good testing with your prints. I am impressed that you printed artificial heart valves. PLA has a glass transition temp (point of when it starts to soften) of 140 F.
you would not think it but the temp inside the car easily gets up to that. I am going to move to ABS (which has a higher temp) once I get a heated print bed.
You can print nylon on your makerbot 2. Big prints warp as they cool and really need a heated print bed. but smaller prints work just fine. the nylon is from a company call taulman and the 2 to use is 618 and 645..
http://taulman3d.com/645-features.html

phoneyman

Awesome, thank you for the info on nylon. Also did not know about the 140* mark, all good stuff to know.

The heated bed was the issue with my prusa. Really need to have a metal surface at least for me. The one I bought softened and warped. Planning to machine a heater plate and maybe build a chamber around it.

John Rygg

Thanks Grapeape I got the gear you sent me.

I have to say that is the smallest gear that I have ever seen !
My printer cannot print to that scale and maintain the detail.
I will see if I can model it and print it and see if the professional printers at shapeways can print it.

I am going to have trouble even measuring the gear it is so small.. I will see what I can do.