Casting Failures---look familiar?

[its_virgil]

Here are some of the failures I've experienced on my journey to cast snake skin blanks. I went through my box of junk and found these which represent my most often produced failures.

 

[JimGo]

Huh...nope, never seen anything like that before in my life.






'cept of course those fifteen or so blanks I have outside in my "reject" pile. [] Thanks, this makes me feel better!

 

[laspringer]

Yes that is what I am talking about.
So do you think that a stable pressure is the
key to most of the problems?

Alan

 

[its_virgil]

Yes I do. When I started hooking the airhose to the paint pot and setting the regulator on the compressor to 30 psi the problems stopped. The pressure doesn't have to leak down very much for the compressor to start and raise the pressure. Just the other day the phone rang and the compressor kicked on. I unplugged it to take the call and guess what? I forgot to plug it back in. When I remembered, the pressure had leaked to 0 and I knew the resin had not had time to cure. I quickly plugged it in and .... ruined cast. Each skin looked like the whitish curddy ones or the silvery ones.

The pictures with the fissures show what too much heat will do. It will cause the resin to crack in that half circle fan shape, or crack the length of the tube.

Once I released the prssure too soom and the resin was not completely cured and I could see little tiny bubbles coming out of the tubes (between the tube and cork) and guess where it was stopping? Between the resin and the skin....caused the silvery look. The wooden standoofs were also ozzing streams of tiny bubbles. I think Curtis or someone called them champaign bubbles.

So yes! I think constant pressure is very critical...can't be allowed to drop and increase and drop and increase ...

My air tank on the comressor builds up 100psi and as the paint pot leaks just a little, the air pressure in the compressor's tank will equalize with the pressure in the pot. Only when the system's pressure falls a little below 30 does the compressor come on and very quickly get the system back to 30 and then cuts off when the compressor's tank is back to 100psi. I think the last time I cast, the compressor came on 3 times in 4 hours. So my leak is very little.

Do a good turn daily!
Don

Originally posted by laspringer
<br />Yes that is what I am talking about.
So do you think that a stable pressure is the
key to most of the problems?

Alan

 

[johncrane]

DON when you said you had failures l did'nt think they could be this bad'obviously there wrecked.about the only thing you could save is the tubes.my thoughts on your good snakeskin pens now is much much higher.

 

[Mudder]

I made my pot like the one posted here before. If I put 40 lbs of pressure in the pot is takes 2-3 hours to leak down to 30 psi. How long do you usually leave the thing under pressure?

 

[its_virgil]

Scott,
I usually cast in the evening and let it "bake while I sleep" just like Mrs. Baird does her bread. It's always cured. But, if I cast at some other time, 4 hours is the minimum for me. But, I'm using only 3 drops of catalyst per ounce. More catalyst will be quicker but hotter and hotter is not better...I've actually cooked the skins right off the tubes. I'm also casting 16 ounces of resin at a time in a mold that is 4 x 7 x 1.
Do a good turn daily!
Don

Originally posted by Mudder
<br />I made my pot like the one posted here before. If I put 40 lbs of pressure in the pot is takes 2-3 hours to leak down to 30 psi. How long do you usually leave the thing under pressure?

 

[its_virgil]

Originally posted by its_virgil
<br />Scott,
I usually cast in the evening and let it "bake while I sleep" just like Mrs. Baird does her bread. It's always cured. But, if I cast at some other time, 4 hours is the minimum for me. But, I'm using only 3 drops of catalyst per ounce. More catalyst will be quicker but hotter and hotter is not better...I've actually cooked the skins right off the tubes. I'm also casting 16 ounces of resin at a time in a mold that is 4 x 7 x 1.

The pictures I posted were of some earlier casts before I "got in my groove" so to speak.

Do a good turn daily!
Don

Originally posted by Mudder
<br />I made my pot like the one posted here before. If I put 40 lbs of pressure in the pot is takes 2-3 hours to leak down to 30 psi. How long do you usually leave the thing under pressure?

 

[its_virgil]

Thanks John. Some have actually been worse but I could not get the results to show in a photograph. Early on I had some skins cook right off the tubes. There was no sign of any skin anywhere in the casting. I guess they just vaporized. Strange things have happened.
Do a good turn daily!
Don

Originally posted by johncrane
<br />DON when you said you had failures l did'nt think they could be this bad'obviously there wrecked.about the only thing you could save is the tubes.my thoughts on your good snakeskin pens now is much much higher.

 

[byounghusband]

There was no sign of any skin anywhere in the casting. I guess they just vaporized. Strange things have happened.

When you find out where all the socks the dryer seems to eat have gone, there too, will you find the cooked snake skins.....[][B)]

 

[Skye]

3 drops??? I didnt know if would even cure at that rate! I may have to try that. I think I was averaging closer to 8 with mine, if not 10. I cant remember off the top of my head. Regardless, I need to lower it. Luckily I havent had the time nor resin lately. Hopefully I can try again this weekend.

 

[TBone]

Originally posted by its_virgil
<br />There was no sign of any skin anywhere in the casting. [?quote]

[:0] Watch out, they've slithered away and are waiting to take their revenge when you least expect it.

 

[ed4copies]

Originally posted by Skye
<br />3 drops??? I didnt know if would even cure at that rate! I may have to try that. I think I was averaging closer to 8 with mine, if not 10. I cant remember off the top of my head. Regardless, I need to lower it. Luckily I havent had the time nor resin lately. Hopefully I can try again this weekend.

Skye,

This is highly dependant on ambient temp and humidity (I believe). When Dawn started casting, she used 7 drops per ounce, about 80 degrees, 80 percent humidity. They cast great, but turning was a PIAAAAAA. (stutter) Now, we wait until we can control the temp and lower humidity and use fewer drops. Pen Potion #9 turns easily, comes off in ribbons unless a very aggressive cut is made - live and learn for US!

 

[ed4copies]

THANKS, DON!!!!

A few mistakes we MAY avoid!!!

 

[BRobbins629]

I think I want to win the raffle. Sounds easier.

 

[johncrane]

ME TOO sound alot easier