Lynxmotion Tech Support

I finished another mold positive last night. I'm going to try to cast a mold tomorrow. I would love to finish the body by the end of the month but I really don't want to rush anything and waste material.

NICE!
Your molds look awesome!

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ROBOTS FTW! ^____^
http://kaizoku-robots.co.uk

What do you use to make that negative mold.. ?
Do you make the true part and have some kind of function to do the mould or you do it manualy ?

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Eric Nantel
Qc Canada

Always liked Robot... Now i am learning to make some...! Wonderfull...

To make the negative mold I'll pour platinum cure silicon into the positive mold pictured above. I'll pour enough so that it overflows just slightly then I'll place a sheet of HDPE on top and clamp it down with some weights. That'll give me a flat bottom. Since this is a deep mold, it's going to be a pain in the ass to get it out of the positive but I machined in a 4 degree draft angle on the outer border so hopefully that will help.

I'm not to sure what you're asking in the second question.

I mean in CAD soft

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Eric Nantel
Qc Canada

Always liked Robot... Now i am learning to make some...! Wonderfull...

Ohhh, yeah I just use the true part. I mate it into a cavity and then machine that. There's no function for it so I just program that g-code as I normally would if I were cutting the part from a block, I just don't completely cut it out.

Mold making is considered an art form. Specialised people within certain industries are pulled in to purely to make molds.
Your method and mold is outstanding. A lot of time has gone into this, and it clearly shows.
What mold release do you plan to use.? I hate to see these things bond.

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Jonny Poole,
Freelance Concept Art & Animatronics, 3D Art and 3D Modelling, as well as Physical Modelling, Mechanical design, and illustration.
http://www.innerbreed.co.uk/
Create, Innovate, Inspire.

I’m very impressed with everything. I have been machining stuff out of aluminum but I like the quality of the molded parts. It looks a little complicated since the mold cavity looks like it has to be a negative to give a positive part and vice versa. I would have to think inverted and I know I would be making a bunch of mistakes. Are the molds a onetime use or can you reuse them over and over again?

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Mike

The robotics nut.

Thanks, man. I really appreciate your comments. As for mold release, Stoner was nice enough to send me a couple sample cans, one of them being spray on silicone release. The silicone doesn't typically bond to anything but silicone but I'm hoping it will help with pulling the mold out of the positive.



Thank you to you, too. With the method I use there's no need to have machine the inverse of the part. And thank goodness because that would definitely be a pain. The picture below shows how I do it. I machine the parts in the prototyping media on the right just as they are, no need for the inverse. Then I pour silicone in it to create the negative which produces the blue mold on the left. The molds with last for 10+ casts at least, the silicone I use is decently flexible. If I'm careful with them they'll last longer.


Michal Zalewskis 'Guerilla's guide to CNC machining and mold making' is an awesome resource. Check it out . http://lcamtuf.coredump.cx/gcnc/

I finished the first negative for the body last night. Unfortunately I had to completely destroy the positive to get it out without completely ruining it. It's a shame, too. That was possibly the best machined piece I've done.
Here's the pic of the mold. It's a little wet in this pic; I was trying to get some of the dust off from when I pulvarized the positive. I'll try to post other pics of the process when I get home from work tonight.

> I finished the first negative for the body last night.

OK, so this is a bit awkward, but I'm the author of the page you referenced in the thread (http://lcamtuf.coredump.cx/gcnc/ . This project is pretty sweet... I'm not really following this forum, and I don't see a way to PM you, but any chance you could drop me an e-mail at lcamtuf@coredump.cx?:-)

Just a quick post to show the first body part that came out. I still need to clean of some of the flash and pour some other molds so I'll try to post more pics later. Sorry the picture quality isn't so great. It's hard to take pics of these white parts without things getting washed out.

stunning.....

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Eric Nantel
Qc Canada

Always liked Robot... Now i am learning to make some...! Wonderfull...

ooow shinny new robot parts!!!

Seconded!

_________________
ROBOTS FTW! ^____^
http://kaizoku-robots.co.uk