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Min Temp for Tank Sealant?

Skybolt Al

Skybolt Al

Well Known Member
I'm freezing my butt off down here in S. Fla & it's about 55 deg in my garage/shop. I want to build my 2nd tank this week. So is there a minimum temperature to use the Flamemaster tank sealant that Van's sells? I did my first tank last month when it was still 90 deg and the stuff cured pretty fast.
 
I was wondering the same thing. I'll be ready to seal my tanks in the near future, but the temp in my shop is probably in the upper 30's lower 40's this time of year (yes, toasty warm...haha). I have a feeling it would be best to wait until spring to do the tanks. I just received my order of sealant from Vans. Should I toss this stuff in the fridge or just leave it in the house at a stable temperature?
 
50 deg. minimum metal surface temperature is what we teach in our Aircraft Sealants class. Cold temps make for longer cure times as well.
 
Also, I don't have the reference in front of me, but the cure time is exponential. 70 degrees takes 12 hours. Every 10 degrees above that reduces the cure time by half while every 10 degrees below that doubles the cure time.

90 degrees = 3 hours
80 degrees = 6 hours
70 degrees = 12 hours
60 degrees = 24 hours
50 degrees = 48 hours
 
I've done tank sealing in the 30's and 40's F. I notice the sealant just begin to stiffen after a couple of hours, but it takes the better part of a week to cure to the point you can't make a fingerprint in it.
 
Keep it warm to mix it.

If it is still cold, move the chemicals into the house for a day or so. It will be a lot easier to mix when warm.
 
Paul:
I'm on the east coast in Boca Raton.

Thanks for the tips everyone. Guess I'll go ahead and build the tank and try to resist sticking my fingers in it for about a week.
 
55 degrees

Skybolt Al said:
Paul:
I'm on the east coast in Boca Raton.

Thanks for the tips everyone. Guess I'll go ahead and build the tank and try to resist sticking my fingers in it for about a week.
Click to expand...

55 degrees, that's tropical, in central California we just got over a cold snap that had us down in the twenties and up to high forties.

It was like that when I sealed my tanks about 5 years ago.

Clamp a regular medium 40 watt light bulb with the aluminum flood light type reflector so nothing is closer than 2 inches. Your could use 2 if you want. It wont over heat because the tank is a huge heat sink.

Give it about a half hour the tank should just be warm to the touch. If necessary put another one near it and re-position it/ them if necessary.

Mine took about 2 days instead of 1 week +

I did this one at a time and left the first one in the jig until it was time for the second.

Best wishes,:cool:
 
Al, Jon has it right. At low temperatures viscosity will be very high. The practical problem is difficult mixing; poor distribution of the manganese dioxide component, more air entrapment, and a very tired forearm. Find a warm place to work.

Curing will take care of itself given proper mixing and enough time. Here's a cure chart from an old Essex publication. Note relative humidity is also a cure time factor.

 
DanH said:
Al, Jon has it right. At low temperatures viscosity will be very high. The practical problem is difficult mixing; poor distribution of the manganese dioxide component, more air entrapment, and a very tired forearm. Find a warm place to work.

Curing will take care of itself given proper mixing and enough time. Here's a cure chart from an old Essex publication. Note relative humidity is also a cure time factor.

Click to expand...

Nice chart- I've been looking for technical information like that on polysulfides. Unfortunately Essex is long gone and Flamemaster doesn't seem to have much literature of that nature available.
 
Thanks Dan...

DanH said:
Al, Jon has it right. At low temperatures viscosity will be very high. The practical problem is difficult mixing; poor distribution of the manganese dioxide component, more air entrapment, and a very tired forearm. Find a warm place to work.

Curing will take care of itself given proper mixing and enough time. Here's a cure chart from an old Essex publication. Note relative humidity is also a cure time factor.
<snip>
Click to expand...

...that nicely explains why my curing time is slow in warm Arizona when the RH is in the 10-20% range.

I could easily guess at the "common rule" of chemical reactions changing 2x for every 10 degrees F, but I never guessed the ProSeal was that humidity sensitive...
 
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