Bees Wax vs Microcrystalline Wax

Use this forum for discussion on kiln casting, pate de verre, and related topics.

Moderator: Brad Walker

Post Reply
Soozin
Posts: 11
Joined: Mon Sep 26, 2005 10:40 pm
Location: NEW ZEALAND

Bees Wax vs Microcrystalline Wax

Post by Soozin »

Hi there

I normally use microcrystalline wax for making my models, however, I have found something I want to use but it is made of bees wax. With mc wax I normally use weight to get volume of glass required (gaffer) so wax weight x 4.2 (gaffer glass) to get the amount of glass I require to cast my work.

If I use bee's wax, would the displacement method work? or is there a formula in which to weight the bees wax (assuming it's differing properties from mc wax) to gaffer lead crystal glass?

Thanks
Susan
Brad Walker
Site Admin
Posts: 1489
Joined: Fri Mar 07, 2003 9:33 pm
Location: North Carolina, USA
Contact:

Re: Bees Wax vs Microcrystalline Wax

Post by Brad Walker »

The densities of bees wax and microcrystalline wax are fairly similar, so you can probably use the same 4.2 factor.

The displacement method would also work.

Check out this chart for an easy way to convert weight to volume for beeswax: http://www.aqua-calc.com/calculate/weig ... ce/beeswax
Soozin
Posts: 11
Joined: Mon Sep 26, 2005 10:40 pm
Location: NEW ZEALAND

Re: Bees Wax vs Microcrystalline Wax

Post by Soozin »

Thanks Brad, after considering this, I decided that displacement method for glass volume would be best, so thank you for confirming my resolution is correct indeed.
Soozin
Posts: 11
Joined: Mon Sep 26, 2005 10:40 pm
Location: NEW ZEALAND

Re: Bees Wax vs Microcrystalline Wax

Post by Soozin »

I made this piece of work a wee bird's nest, I used water displacement and got the mould filled perfectly.

I used a normal 1:1:1 on investment like normal, cast the piece but the investment has gotten in to the glass (I used spaghetti wax)... the only way is to drill the investment out.

this is my second attempt at my nest series... any advice with moulding up spaghetti wax... I am just wounding it around to make it a round nest, once it's done, I mould it up, steam it out.

I don't know why investment is getting INTO the actual glass.. I cast at the same temp as my others and I am using Gaffer Glass for these.

Susan
Morganica
Posts: 1079
Joined: Mon May 19, 2003 6:19 pm
Location: Portland, OR
Contact:

Re: Bees Wax vs Microcrystalline Wax

Post by Morganica »

More than likely, the problem is with the engineering of the model and creation of the negative space.

If you've simply coiled strings of wax you've likely got some pretty thin, fragile outcrops of plaster in that mold. The glass and investment will be expanding and contracting at different rates (unless the COE of your investment matches the plaster), and it's very, very easy for pieces of investment to break off. It's even easier if your steam-out went a bit too far and dissolved more investment surface than expected.

Once those pieces are loose in the mold, they're readily trapped in the glass flow. Even if they're not loose, the action of glass moving through the mold can break off small pieces of investment. Both can be trapped as the glass moves through the mold. In addition--I don't know how thin those strings are, but if they're very thin the glass could be too viscous to flow down the tubes and instead break through, carrying plaster with it. (That last is less likely; I would expect stiffer soda lime to do that before Gaffer)

I run into these problems with some of my very detailed, layered pieces occasionally--it usually means that I need to first sculpt the model, and then spend some time modifying it to clear paths for the glass. Generally, that means adding wax/clay "bridges" between elements, where it doesn't show. If I need the voids, I've got to ensure I've got enough surrounding bridges to carry the glass past without breaking. And if those "strings" of wax are very thin, you may need to simply construct your nest on either side of a solid structure, like a bowl, and add the string on top.

You might also check your processes--how long does your mold sit between investing and steaming? Between steaming and putting in the kiln? What investment mix are you using and how are you mixing it? Are you allowing enough cure time? Are you building a reservoir into the mold for the glass, suspending the glass in a separate carrier over the mold, or putting the glass down IN the mold? That kind of stuff can make a difference.
Cynthia Morgan
Marketeer, Webbist, Glassist
http://www.morganica.com/bloggery
http://www.cynthiamorgan.com

"I wrote, therefore I was." (me)
Soozin
Posts: 11
Joined: Mon Sep 26, 2005 10:40 pm
Location: NEW ZEALAND

Re: Bees Wax vs Microcrystalline Wax

Post by Soozin »

Thanks for that. You are correct in that I am just coiling it and moulding it up like I normally do 1:2 (1 wet, 2 parts dry plaster/silica).

Because it was so small, I didn't need to use a reservoir and used a flower pot.

Once I made the wax, moulded it, steamed it out then cast it.

I am now trying to add the coils over a new wax form.. hmmm... I will keep trying until I get it!

Thanks for the advice, morganica!
Post Reply