HF PP how long

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SantaEric

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Jun 15, 2011
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buford ga.
First off, how long under pressure to keep pen blanks in a PR mold? I thought I understood someone to say 26lbs of pressure and just now I see 51lbs so which is more correct. Also, the PR has the catylyst in it so I assume the PR is hard by now. I put it in at 315 today so when would be best time to remove and why?
 
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Justturnin

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Aug 19, 2011
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I just did some and left it at 50PSI (my pots max) for about 20 hours. I know Alumilite is less but I think PR needs to be about a day. As far as why I am not 100% sure. PR will shink and I think the Pressure keeps pushing th PR Down into the wood so it will not seperate. Now if you are only using PR w/ no medium I would not even put it in the pot.
 

sbell111

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Franklin, TN
You want to keep it under pressure until it hardens. How long that is depends on many factors such as temperature, amount of catalyst, type of colorant, age of resin/catalyst, etc. I'm of the belief that extended tome under pressure will not cause the resin to not shrink nor will it 'force the resin into the wood'.
 
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SantaEric

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Jun 15, 2011
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buford ga.
I just did some and left it at 50PSI (my pots max) for about 20 hours. I know Alumilite is less but I think PR needs to be about a day. As far as why I am not 100% sure. PR will shink and I think the Pressure keeps pushing th PR Down into the wood so it will not seperate. Now if you are only using PR w/ no medium I would not even put it in the pot.

not to sound like a total goob...what is a "medium" are you talking about the wood that I placed into the mold and then poured the PR in and around?
 

PenMan1

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Jul 8, 2009
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Eatonton, Georgia
Eric, In Buford, Georgia, this time of year, 26 LBs of pressure is PLENTY of pressure for a "non-embedded" blank. Leave it, (based on our current weather schedule warm, +/- 70 degrees and 99 percent humidity), until 9 pm tomorrow night. That may be a little "long", but when you take it out, it'll be fine.

If you embedded items (including "worthless castings"), leave it longer, if you can. Casting is TOTALLY dependant on enviromental conditions, the thickness of the pour, and the amount of catalyst added. If you added 4 drops of MEKP per ounce, at 9:00 pm tomorrow, your blank will have no bubbles and be "just tacky" on the surface.

AND, Welcome to the "neighborhood"!


Edit: and oh yeah, something I forgot, "feet above sea-level" also has a BIG influence (Until Denver got into Pro Baseball, Atl Stadiuim was called the "launching pad" 762 feet above sea level ( you are 32 miles away). Being a NATIVE of Flowery Branch, 30542, I KNOW your weather. Are you SURE you want to claim Buford as home? Sugar Hill sounds more "ritzy" :)
 
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PenMan1

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HEY, WAIT! I think I ACTUALLY know you!

Do you travel with a horse trailer, a NIZE looking photographer and 2 MEAN reindeer whose "real" names are Buck and Charlie and have REALLY BAD toilet manners?
 

PTownSubbie

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Chesapeake, VA
HEY, WAIT! I think I ACTUALLY know you!

Do you travel with a horse trailer, a NIZE looking photographer and 2 MEAN reindeer whose "real" names are Buck and Charlie and have REALLY BAD toilet manners?

LOL!! You crack my up Andy! You REALLY do know everybody!!! LOL!!
 
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