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General Forestry => General Board => Topic started by: Qweaver on January 08, 2006, 11:49:04 PM

Title: Buying insulation?
Post by: Qweaver on January 08, 2006, 11:49:04 PM
I'm not sure where is the best place to post this question but here goes.
I'm thinking of buying foam insulation in large blocks and setting up a hot wire table to custom cut it for a Timber Frame.  I had a small setup years ago to cut model aircraft wings and it worked well.  My questions are:
Where to buy the foam and where to get a plan and materials for the hotwire table.
TIA
Quinton
Title: Re: Buying insulation?
Post by: getoverit on January 09, 2006, 12:23:39 AM
You can actually just buy the liquid styrofoam (in 2 parts) from most marine (boat building) dealers. Just build yourself a 4' X 4' X 8' "mold" and mix up enough to pour your own. They use it to meet the new coast guard requirements for keeping boats afloat by filling all of the empty spacers between the inner and outer hulls.

try this link (http://www.marinefoam.com/liquid-sprayin-foam.html)
Title: Re: Buying insulation?
Post by: jon12345 on January 09, 2006, 02:26:38 AM
A table might be a lot of extra work to build and handle the pieces.

I did a little searching and found that you can  make a hot-wire cutter out of a soldering gun and that it can be adapted by replacing the tip with a piece of iron wire.
Title: Re: Buying insulation?
Post by: sprucebunny on January 09, 2006, 08:22:26 AM
You can cut it with any saw. If the blade doesn't go all the way thru, it snaps pretty clean then you can clean up any edges with a steak knife.

I've used the poured stuff. It didn't level very well for me . The kind I had ( for a boat, 2# ) was expensive but I didn't compare the mixed volume to the price of any other foam.
Title: Re: Buying insulation?
Post by: woodbowl on January 09, 2006, 09:17:30 AM
Quote from: Qweaver on January 08, 2006, 11:49:04 PM
My questions are:.....................   where to get a plan and materials for the hotwire table.


Quinton,
    I built a full size composite aircraft several years ago. I borrowed my dads ping pong table and stretched piano wire across the middle with a turnbuckle on the side to adjust the tension. A regular 12 V car battery is the power source. The voltage regulator is nothing more than 2 or 3 feet of electric fence wire rolled up on a stick, pull the stick out and let the coil will "free air" to bleed off the excess heat. Too hot? Add more coil...... Not hot enough? Choke up on the coil........  Piano wire gets red hot and snaps? Definitely need more coil! ............ Heat will cause the piano wire to slack up a bit. Adjust with turnbuckle to suit. ............ Works like a charm.
Title: Re: Buying insulation?
Post by: karl on January 09, 2006, 06:21:31 PM
We have taken to hiring a pro to foam in place our projects- make sure the pro uses closed cell polyurethane as it is a better insulator and does not absorb water. R value is 7 per inch. There are several brands- we use Corbond, search for info and dealers in your area.
We have found it to be as economical as trying to fit every nook and cranny- then having to foam around the sheets that break or don't fit twisted or bowed lumber. The stuff adds some structural integrity also and you dont need a vapor barrier - real handy for those "designer situations"
Title: Re: Buying insulation?
Post by: rebocardo on January 10, 2006, 02:02:30 AM
www.usplastics.com

# 45374  Hot wire knife?

You can get it with varying cutting depths. Just run it along side a 2x4 for straight cuts. I thought they sold the sheets at Home Depot, foam (white plastic)  on one side, foil on the other?

I agree with the spray in, especially if it is open and you can run the plastic sheets (to retain the foam) right over the exposed studs.