flubber

[simonbaker]

How the heck do you cut nice holes in latex rubber, like the latex mold I made for casting coils?

Don't even think about drilling it - it will grab your drill bit and wrap around it faster than you can say "Ellen Ripley".






Even hard to cut with knife or pierce with needle. Tough stuff.

-SB

[Tinkerer]

Dip it in liquid nitrogen. It gets hard as a rock.

Tinkerer

[simonbaker]

Dip it in liquid nitrogen. It gets hard as a rock.

Tinkerer

You said it -- I'll hammer it after that. This mold idea is not the way to go.

[Tinkerer]

Yeah, liquid nitrogen might be pushing it, but you could try with a blast of Co2 from the fire extinguisher.
Sometimes I need a hard to get rubber seal. I take the old broken one to the rubber shop, where he turns a new one on the lathe. I think this is the way he gets the rubber hard enough to hold and turn it in the lathe.

For temporary molds I prefer silicone rubber. It comes in all grades of hardness.

For small parts, the "lost wax method" works good.

Hey, is that your brain, on the picture?????

Tinkerer

[simonbaker]

Yeah, liquid nitrogen might be pushing it, but you could try with a blast of Co2 from the fire extinguisher.
Sometimes I need a hard to get rubber seal. I take the old broken one to the rubber shop, where he turns a new one on the lathe. I think this is the way he gets the rubber hard enough to hold and turn it in the lathe.

For temporary molds I prefer silicone rubber. It comes in all grades of hardness.

For small parts, the "lost wax method" works good.

Hey, is that your brain, on the picture?????

Tinkerer

Maybe silicone is better way - but maybe sticks and harder to get off the shaper? Much easier to drill I'm sure. I'll check that. Thanks.

Yes, my brain. Now you know where my ideas come from. Pay no attention to the outfit, it was just a phase...

-SB

[Götz von Berlichingen]

Try a Leather Punch or Hollow Punch.
http://commons.wikimedia.org/wiki/Ca...hes?uselang=de

[simonbaker]

Try a Leather Punch or Hollow Punch.
http://commons.wikimedia.org/wiki/Ca...hes?uselang=de

Might work, but the rubber really resists incisions.

I wonder if you can burn a hole with a soldering iron or such. Probably a smelly mess.

I have pretty much concluded the rubber mold isn't easy to work with. Plus you have to cut it some to get the cable out when you're done molding your coil. But it potentially can make nice shaped coil heads.

The plastic shell like dfbowers can't be beat, for integrity, appearance, and ease of work. You just have to have the equipment and skill to make the shell.

For experimenting, I'll try some other quick-and-dirty methods. Like gluing coil to thin flat wood panel, maybe making a simple mold out of plasticene to contain the glue and add structure. The hard part is making the fork that attaches to the pole. A tough "U" shaped piece of plastic would be good, embedded in glue or held with plastic screw. But where get such a piece? May need to use wood. And then there's bamboo...

-SB

[Qiaozhi]

Might work, but the rubber really resists incisions.

I wonder if you can burn a hole with a soldering iron or such. Probably a smelly mess.

I have pretty much concluded the rubber mold isn't easy to work with. Plus you have to cut it some to get the cable out when you're done molding your coil. But it potentially can make nice shaped coil heads.

The plastic shell like dfbowers can't be beat, for integrity, appearance, and ease of work. You just have to have the equipment and skill to make the shell.

For experimenting, I'll try some other quick-and-dirty methods. Like gluing coil to thin flat wood panel, maybe making a simple mold out of plasticene to contain the glue and add structure. The hard part is making the fork that attaches to the pole. A tough "U" shaped piece of plastic would be good, embedded in glue or held with plastic screw. But where get such a piece? May need to use wood. And then there's bamboo...

-SB

You could also try a sheet of SRBP (synthetic bonded resin paper). In other words, the base material of a PCB without the copper. Should be quite easy to cut and more stable than wood. Might be difficult to find somewhere that it sells it as a plain sheet which would be large enough for a coil.

[simonbaker]

You could also try a sheet of SRBP (synthetic bonded resin paper). In other words, the base material of a PCB without the copper. Should be quite easy to cut and more stable than wood. Might be difficult to find somewhere that it sells it as a plain sheet which would be large enough for a coil.

Thanks, sounds good -- looking for light strong thin material.

Resin (ugh) over balsa wood might be a possibility too. Or stuff use for model airplane wings.

-SB