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Yes, the new furnace is electric.  I was really concerned about torch melting in the basement.  I'll likely reserve that for the backyard when I need to smelt/purify gold and silver as the electric melter works best with already purified metals.

 

So tonight or tomorrow, I plan to start clipping the spines off of the tree and adding them to the sculpt I am creating.  I am very excited at how well the cast turned out.  There is very little clean-up needed at this point, as I took the time and cleaned up most of the flash on the wax copies.  It is a lot easier to de-flash wax than pewter.

 

Andy

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Trogs Get Cast 1

 

Many of you will remember my Trogs WIP that I did on here. I did actually finish them both, but just never really got around to posting them in that WIP.  I have been unable to find a home for them, because they do not easily correspond to any typical D&D or PF creature. I had a brief lull in my sculpting projects this past week and decided to try to cast them myself.

 

I started with Smilely, because he is my least favorite (Hugs turned out bad-elf, if you ask me, and I want more experience before I mold it).  I cut off both its arms.  I probably could have left the left one on, but my abilities aren't great yet, and I was afraid it would complicate things too much.  I didn't make a sprue for the arms and just winged it, using a sprue former in the mold, figuring that I would cut channels to the arms.  That turned out to be a bad idea and they moved in the liquid rubber mold. I barely had enough space for the wax injector. It all worked out though.  Here is the mold and a few wax copies of the arms (I went on to make many more; injecting molds is fun):

 

01.jpg.441ebd6a75560600b639ca7cbfc68d71.jpg 02.jpg.63d7949886428f05022e05c6480f36a5.jpg

 

Then I decided to tackle the rest of Smilely.  First, I added a GS and wire sprue and let it cure:

03.jpg.ad177e3865965e086a5ddfcc6623fea4.jpg

 

 

Next, I created the rough mold, supporting the model and creating the basic parting line:

04.jpg.66d598fd6757d414d8bd138453b4bcbb.jpg

 

 

Here is a shot of the complete stack of unvulcanized mold rubber before peeling the paper and putting it in the mold frame:

05.jpg.6525444a3c989c7ff7e95f12c4cd4d58.jpg

 

 

The mold turned out great, but I cut myself very deeply with the scalpel while cutting in the air gates.  It was such a clean cut though I was able to seal it myself, so no ER trip at 11:00 at night.  Here is the finished mold:

06.jpg.e8965cb3dce3146347885076211267bd.jpg

 

 

Smilely though wasn't as heal-able as I am and lost several layers of putty in the mold making process, so I guess I'd better cast it right:

07.jpg.732aa25a0af33007eff3218aaba23b1a.jpg

 

 

I'm not used to doing this large of wax casts, and I opened the mold too soon, oops:

08.thumb.jpg.18cc3301f7b92bb29833a3e8893f5e13.jpg

 

 

The next one came out beautifully:

09.jpg.650886c29bb9dcf3822762331ed5c871.jpg

 

 

I kept making casts.  Sometimes air bubbles in the cast really suck:

10.jpg.e91f7ed23d32741fc3ed9241704a2352.jpg

 

 

I decided I'd made enough when my "Keeps" bowl started looking like Siri's cave drawing:

11.jpg.33475d276d941c4c4a8d15bc84860230.jpg

 

 

It will be a couple of weeks before I can invest and cast these, but I got the hard part done.  I am very excited that I successfully made a mold for a mini.

 

Andy

 

 

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Yeah, the detail came through perfectly.  I'm having a bit of an issue with mold alignment at his nose, but no where else.  Also I'm having some air bubble issues, but most are contained inside the mini which will still work fine for investment.  The next step is to de-flash them and do clean-up using sculpting wax.

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Nice waxes, the keepers look great!  Looking forward to seeing as much of the rest of the process as you feel like sharing.  What are you gonna cast these in?  ie. will they be pewter miniatures... or bronze statuettes?  :)

 

I won't even look at an X-Acto knife (the closest thing to a scalpel that I own and hands down the most dangerous thing in my shop (which contains a radial arm saw and sometimes molten metal)) without making sure I have a bottle of krazy glue (CA)  handy.  Quickly closes up small but bloody cuts on the fingertips and lets you get back to work within a minute or two.  The alternative being to allow your SO to see what you did to yourself and insist that you go to the ER for stitches and stop talking crazy about just quickly closing it up yourself with a little drop of CA.  You will wait in that ER, oozing blood through a series of wadded up paper towels, for at least 3.5 hours until a doctor appears, takes a quick look... aaaaaand just quickly closes it up with a little drop of CA. 

 

Kang

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2 hours ago, Kang said:

Nice waxes, the keepers look great!  Looking forward to seeing as much of the rest of the process as you feel like sharing.  What are you gonna cast these in?  ie. will they be pewter miniatures... or bronze statuettes?  :)

 

I won't even look at an X-Acto knife (the closest thing to a scalpel that I own and hands down the most dangerous thing in my shop (which contains a radial arm saw and sometimes molten metal)) without making sure I have a bottle of krazy glue (CA)  handy.  Quickly closes up small but bloody cuts on the fingertips and lets you get back to work within a minute or two.  The alternative being to allow your SO to see what you did to yourself and insist that you go to the ER for stitches and stop talking crazy about just quickly closing it up yourself with a little drop of CA.  You will wait in that ER, oozing blood through a series of wadded up paper towels, for at least 3.5 hours until a doctor appears, takes a quick look... aaaaaand just quickly closes it up with a little drop of CA. 

 

Kang

 

I'm torn between bronze and pewter.  They cost about the same with bronze being a bit less expensive.  Bronze is currently running $14.40 to $19.50 a pound depending on the mix and pewter is $17.99 a pound.  I love the way that everyone thinks that bronze is the more valuable material, but that just isn't true.  We use pewter because of it's low melting temperature, not because of its cost. With the high volume casting that mini companies use, if you tried to use bronze, the 1800+ degree pour temp would completely melt/vaporize the rubber molds. With my setup it is an option.  That said, I do want to paint these guys.  Has anyone tried painting bronze?  How does it take priming and such.

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On 4/18/2017 at 1:13 PM, TaleSpinner said:

 

I'm torn between bronze and pewter.  They cost about the same with bronze being a bit less expensive.  Bronze is currently running $14.40 to $19.50 a pound depending on the mix and pewter is $17.99 a pound.  I love the way that everyone thinks that bronze is the more valuable material, but that just isn't true.  We use pewter because of it's low melting temperature, not because of its cost. With the high volume casting that mini companies use, if you tried to use bronze, the 1800+ degree pour temp would completely melt/vaporize the rubber molds. With my setup it is an option.  That said, I do want to paint these guys.  Has anyone tried painting bronze?  How does it take priming and such.

 

I just found a source where I can get 10 to 11 pound silicon bronze ingots for sale for about $7.00 a pound.  That's only about 40 cents over copper melt cost! I may be placing an order. The only problem is that I would have to cut it up into chunks to fit it into my crucibles, and all of my metal cutting tools are miniature. :lol:

 

9110-10-00-2T.jpg?1477230448

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On 4/20/2017 at 3:09 PM, TaleSpinner said:

 

I just found a source where I can get 10 to 11 pound silicon bronze ingots for sale for about $7.00 a pound.  That's only about 40 cents over copper melt cost! I may be placing an order. The only problem is that I would have to cut it up into chunks to fit it into my crucibles, and all of my metal cutting tools are miniature. :lol:

 

9110-10-00-2T.jpg?1477230448

You don't have a reciprocating saw or a hacksaw? ???

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2 minutes ago, knarthex said:

You don't have a reciprocating saw or a hacksaw? ???

 

If it's anything like I had to go through when cutting down tin ingots to fit in my crucibles, then I should warn that that process ended up being a major pain in the rear and much more difficult than I expected.  I was doing it by hand with a hacksaw and vise, though, so maybe a reciprocating saw would have been the way to go.

 

In the end, however, once I had the large ingots cut up, I generally melted them down and made my own, much more crucible-friendly ingots using the leftover metal at the end of each cast.

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If you can afford it, get yourself one of those portable band saws for jobs like breaking thick ingots apart; hacksawing them will be No Fun At All and a reciprocating saw will work faster (get a metal demolition blade for it if you go this route) but it will leave your hands numb for hours afterwards - I've used both methods to beak up scrap aluminum car wheels, which don't have any sections as thick as those ingots look, for the crucible; been there, done that, no thanks.  Better to chuck them on a bonfire until they get crumbly then whack them to bits.  But that would not work with bronze, you'd need to build a whole new furnace.  So, the portaband is probably your best bet.  Heck, a full sized metal cutting bandsaw would work great too but would be massive overkill and far more expensive.  Maybe you can find a used portaband on Craig's List for cheap, or find a new one on sale.  I have had my eyes out for a good deal on a used one for a while now, but so far no luck.

 

Painting bronze, my only real concern would be that it is prone to oxidization.  I've seen everdur sculpture castings with very nice patinas.  If this bronze decides to grow a natural patina underneath your paint job, how will that affect it?  Turn it green?  Hard to say, I'd make sure to seal it once the painting is complete (or maybe seal the bare metal before painting?  I just don't know) and hopefully keep the air away from the bronze as much as possible.  At that price and since you'd be doing investment casting even if you use pewter, casting in bronze may actually save you some money.  Not sure, you'll save money on the metal but not on energy/fuel for melting it; you'd have to do the math and maybe a little experimenting to figure out which is more economical.  Probably not a huge difference per piece anyhow.  I found a couple of marine forums fairly easily (google "primer for bronze") where people were discussing using 'etching primers' for painting bronze...  I thought that etching was how all primers worked; maybe some etch more aggressively than others?  Anyhow, it was probably not everdur being used in these marine applications, but perhaps the primer and painting info is transferrable. 

 

If you go with the bronze, I hope you will keep a few castings to display in naked metal as well, at the very lest it would be an interesting curiosity.  It sure isn't something you see every day...  You could even try chucking one or two in a bucket of salt water for a couple months, I've read this gives a nice (and durable!) verdigris effect, though the patineurs probably have an alchemical/potion-ingredient sounding reagent (they all have names like "liver of sulphur") for doing that within just a few minutes.  This might be an easy way to make some nice miniature statues for your dungeon/ruins game setting or what have you.

 

Kang

 

edit - muffin pans etc. make decent ingot molds, maybe you would need the pans for making mini-muffins, depends on how big the mouth of your crucible is.  Don't use a brand new pan though, burning Teflon is extremely nasty (google polymer fume fever, we're talking birds falling out of the sky dead here), but a well used pan will work fine.  Better still if they are a little rusty or perhaps coated with graphite or soot - then the ingots will want to stick less, and that is good because with copper alloys having your ingots actually braze themselves to the ingot mold is a real concern (trying to pour ingots on the cool side if you can as well should also help).  Always preheat your ingot molds to prevent residual moisture from causing a steam explosion that will fling molten metal at your face, but if you are using cast iron ingot molds it also helps prevent them from cracking from the thermal shock.  Eventually it might make sense to weld up some ingot molds of a suitable size using angle iron,  When I am going to need to pour a bunch of ingots, I sometimes mold up the bottom of my mini-loaf baking tray in green sand, that way I can pour ingots in there as well as in the loaf pan itself.

Edited by Kang
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For cutting metal like that, I'd suggest picking up a cut off saw.  You can get a 3 HP with a 14 inch blade one from harbor freight for under a hundred and should make quick work out of something like those ingots. Even the better name ones aren't too pricy.

 

This topic has been fascinating...

 

 

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