Petro Bond Mix 7 of 9
Posted: Sat Jun 11, 2022 11:57 am
If anyone remembers Murray from AA. A professional Foundryman from British Columbia, Canada. He and I had been chatting on the side for a while and then he kind of dropped out of site. He had this recipe for petrobond sand that he developed for his use and I'm going to try to copy it as close as I can. OK, maybe I'm changing everything and hope it works.
Here's his original formula. I'm glad I saved it before AA went down. He called it 7 of 9 because he had tried 9 different mixes and batch #7 worked the best. I'm sure it had nothing to do with a Star Trek Voyager character.
Okay, 7 of 9
100 lbs # 92 silica
100 lbs # 58 silica
14 pounds of Petrobond clay, or Petrobond 2 no difference really, exept Petrobond 2 suposedly has the catalyst in it already, but I find no difference.
8 pounds of Sunoco Sunpar 115 Napthenic oil
140 ml of p-1 Catalyst I believe you can use alcohol with 10% water in it, the water is very important. The alcohol carries the water to the sand grains and finishes the catalization, you see a very noticable difference in the green strength immediatly after adding the cat.
This mix is designed to sit indefinately without changing and is way far outside the recommend recipes which call for far less Clay and oil. It is at it's best though after sitting for several weeks really but can be used right away.
Mix dry ingredients add oil slowly, mix for 15 minutes or so (that's what I do) then add catalyst and mix another 3-4 minutes and your done. Like I said I went through 9 mixes and this for me is the best combination of grain size, strength and wetness if you will.
Murray
P.S. I should state that this is "one use" only sand for me.
My Mix. 50 pound batch mulled by hand.
50 pounds of Silica sand
3.5 pounds of Petrobond
2 pounds of synthetic outboard motor oil
35 ml dry gas alcohol 90% water 10%
My sand is silica sand from a foundry but I don't know what size it is. I have petrobond clay that I got years ago from 4cylfoundry (I think).
The oil looks like it only come in 5 gallon cans, so I'll use sythetic Outboard motor oil because it's supposed to be high temp. I guess alcohol is whatever you can find but I have ethanol with 10% water.
Murray only used his petrobond once and just had it against the pattern and then filled the flask with his greensand or Pepset sand. He liked the surface he got with the petrobond.
Here's his original formula. I'm glad I saved it before AA went down. He called it 7 of 9 because he had tried 9 different mixes and batch #7 worked the best. I'm sure it had nothing to do with a Star Trek Voyager character.
Okay, 7 of 9
100 lbs # 92 silica
100 lbs # 58 silica
14 pounds of Petrobond clay, or Petrobond 2 no difference really, exept Petrobond 2 suposedly has the catalyst in it already, but I find no difference.
8 pounds of Sunoco Sunpar 115 Napthenic oil
140 ml of p-1 Catalyst I believe you can use alcohol with 10% water in it, the water is very important. The alcohol carries the water to the sand grains and finishes the catalization, you see a very noticable difference in the green strength immediatly after adding the cat.
This mix is designed to sit indefinately without changing and is way far outside the recommend recipes which call for far less Clay and oil. It is at it's best though after sitting for several weeks really but can be used right away.
Mix dry ingredients add oil slowly, mix for 15 minutes or so (that's what I do) then add catalyst and mix another 3-4 minutes and your done. Like I said I went through 9 mixes and this for me is the best combination of grain size, strength and wetness if you will.
Murray
P.S. I should state that this is "one use" only sand for me.
My Mix. 50 pound batch mulled by hand.
50 pounds of Silica sand
3.5 pounds of Petrobond
2 pounds of synthetic outboard motor oil
35 ml dry gas alcohol 90% water 10%
My sand is silica sand from a foundry but I don't know what size it is. I have petrobond clay that I got years ago from 4cylfoundry (I think).
The oil looks like it only come in 5 gallon cans, so I'll use sythetic Outboard motor oil because it's supposed to be high temp. I guess alcohol is whatever you can find but I have ethanol with 10% water.
Murray only used his petrobond once and just had it against the pattern and then filled the flask with his greensand or Pepset sand. He liked the surface he got with the petrobond.