Casting from an original carving #4: Creating the Mother Mold - part 1(brainstrain for you)

That’s the part I can’t wait to see.

Even for much smaller object I get some deformation.

I never got 3/8 in rubber thickness. When I apply my 5 coats of ruber I get about 1/8. Different material for sure.

Thanks for taking the time and doing that series.

Ian, for small parts, I do not use this same process – I lay half of the object in putty and make a wall around the other half into which I pour a liquid rubber over the figure, covering at least 1/2” past the highest point.
After it’s dry, I turn it over, lubricate the rubber and repeat the process for the other half of the figure…using some marbles for register guides.

That amount of rubber on each side is it’s own mother mold and would fit and clamp together easily without too much seepage or distorion.

This is only 1.5” tall

-- http://www.jordanstraker.com

It is a gourd right? You could just eat it, and you would be left with just the rubber mold.

I will go back to work now.
Steve

-- -- I'm no rocket surgeon

Yes you are Steve – “No rocket surgeon” LOL!

-- http://www.jordanstraker.com

Thanks Jordan.

I am going to try that.

This interests me greatly. I have a friend who carves “butter block(?)” for lost wax casting. It’s always fascinated me.

-- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog

Oh… that makes sense…

Looks like you’d have to stabilize the center portion by filling it with something to maintain that shape resulting in really maybe two molds… a male for the inside & female for the outside…

No questions… just running-off of the brain… LOL

I gotta see this happen!

Thank you Jordan.

-- Have Fun! Joe Lyddon - Alta Loma, CA USA - Home: http://www.WoodworkStuff.net ... My Small Gallery: http://www.ncwoodworker.net/pp/showgallery.php?ppuser=1389&cat=500"

You’re very wise Joe…but how do you get the inside hard section out after you’ve poured something juts as hard into it? Stay tuned.

-- http://www.jordanstraker.com

You bet I’m interested, Jordan. Even if I don’t have any plans to make one, which I co, it is fascinating just to know how ! ! ! It’s great that you’re willing to share this with us! Thanx ! ! !

-- Paul - The sweetest sound in my shop, next to Mozart, is what a hand plane makes slicing a ribbon.

”You’re very wise Joe…but how do you get the inside hard section out after you’ve poured something juts as hard into it? Stay tuned.”

That’s Your problem! LOL…

I don’t think you’re going to cut the works in half like drinking glasses, etc. are done…
(but, maybe you will… I’m waiting…)

I am patiently waiting to see your solution in your good time… no rush here… it’s just pounding at my brain… that’s all… LOL…

Seriously… take your time… don’t let me RUSH you… LOL

This is great!

-- Have Fun! Joe Lyddon - Alta Loma, CA USA - Home: http://www.WoodworkStuff.net ... My Small Gallery: http://www.ncwoodworker.net/pp/showgallery.php?ppuser=1389&cat=500"

Jonathan, this is one of the ideas I toyed with prior to my solution. I even thought of filling it with water and freezing it then thawing afterwards. Many problems lie there as far as the coldness when you pour your hot wax as it would set up too quickly as well as seepage of water. Also the weight of whatever you put in it, sand or what have you, it would push the inside of the empty rubber to the outside of the empty rubber. Remember my original vessel is only 1/4” thick so I have very little room for distortion.

Good thinking though.

-- http://www.jordanstraker.com

As an ex-mold maker, I would stabilize the interior section of the mold…..hmmmmmm. nope I think I would rather see what that brilliant mind of yours came up with.
I have used many gallons of the liquid latex in mold making.
Back to chomping at the bit. :-)

-- Can't never could do anything, to try is to advance.

Are you really trying to pickup the detail of the inside of the gourd or just make it a hollow casting in bronze? Build up a hollow wax shell by pouring the molten wax in and out again until you get the desired thickness.

If you must have the interior mold how about packing foundry sand into the hollow cavity. Dig it out to release the inner mold after casting.

-- E.R. Bunn, http://www.hollandmountainwoodworks.com

I am wanting to get the interior of the gourd as it is so incredible, thus my choice not to slush the interior. The more I can do and the less the foundry does, the more money I save.

-- http://www.jordanstraker.com

Very interesting and I have gained lot of information from you Jordan. Just want to join the projection part of the situation… You will cut the bottom part and stretch the rubber to the top by peeling it off… The inside part will be push little bit from the bottom with small hole including the gourd then peeled up to the opening. What will be left is the bottom part with hole. This could be sealed after inserting a heavier wood or plate for it to stand and balance the whole thing…
Ahhh… you made me think a lot, Thanks for my brain exercise.

-- Bert