Using heated trowel to Form Micro

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wsimpso1

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I found it completely necessary. I know that I saw it on Wayne Hicks' build log. Here is where I have written about it and cited web pages:

https://www.homebuiltairplanes.com/forums/threads/billskis-fiberglass-bird.8344/page-2#post-430037

I have used it. Kept the heat gun hung on a rope over a hook on the ceiling, for every pass of the 6" drywall knife, I would warm the back of the blade with the gun, make the pass spreading the dry micro. If I forgot to warm it, instead of spreading the micro and forcing it into the fiberglass surface, it would stick to the dry wall knife better and roll up behind the pass. The heat gun kept the knife hot enough that the resin would be just a but slick and would spread nicely.

Billski
 

Pops

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I'll remember that. Have needed it several times.
Thanks.
 

Bill-Higdon

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I found it completely necessary. I know that I saw it on Wayne Hicks' build log. Here is where I have written about it and cited web pages:

https://www.homebuiltairplanes.com/forums/threads/billskis-fiberglass-bird.8344/page-2#post-430037

I have used it. Kept the heat gun hung on a rope over a hook on the ceiling, for every pass of the 6" drywall knife, I would warm the back of the blade with the gun, make the pass spreading the dry micro. If I forgot to warm it, instead of spreading the micro and forcing it into the fiberglass surface, it would stick to the dry wall knife better and roll up behind the pass. The heat gun kept the knife hot enough that the resin would be just a but slick and would spread nicely.

Billski
Thanks, I can't remember where I heard/read about it the first time. I've toyed with the idea of building a heat/temperature controlled trowel
 

Bill-Higdon

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I've thought of that, or taking a surplus heated plate couple a temp controller & apply Kapton film to the surface. I've used heat to get epoxy to flow into areas th seal them in the paste. It was part of an ISO documented procedure.
 

Kyle Boatright

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I've thought of that, or taking a surplus heated plate couple a temp controller & apply Kapton film to the surface. I've used heat to get epoxy to flow into areas th seal them in the paste. It was part of an ISO documented procedure.
How 'bout an old fashioned clothes iron with modifications to close the holes that are usually in the sole plate?
 

wsimpso1

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You could use a sealing iron as a trowel.
I did not even know what it was until I looked it up. Looks like the irons we use for shrinking polyester fabric.

A 6" drywall knife is about as big as this old man can press micro onto a wing.The epoxy in the micro has to be spread on and pressed in long before it gells because you are counting on resin migrating down to the bond line and out of the stuff closer to the surface for easy sanding. A sealing iron would really reduce your workable batch size and make the job run a long time. Sort of like painting a house with a 1" brush.

A clothes iron, hmm, have to think on that one a bit. Go buy one at the second hand store and see how it works.

Billski
 

Bill-Higdon

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How 'bout an old fashioned clothes iron with modifications to close the holes that are usually in the sole plate?
I did some research, they make "dry" irons also, in other works they don't have the holes in the plate, water reservoir etc. If they don't come with a none stick coating put a big piece of the kapton film they use on 3d printers on the sole/face.
 

berridos

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I hate to spread micro and the results were always poor.
I switched to a 2 component PU filler than was amazingly easy to distribute, sticky and creamy and much easier to sand and always remained very flexible. The product is used in wind blades. The problem the stuff was pricey and i used a lot of it.
 

cblink.007

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I can't remember where I heard of using a heated trowel to form freshly laid "Micro", but what is everyone's opinion of this?
I gave this method a shot earlier today on a test piece... seemed to work well with thick micro paste. I was using EcoPoxy slow cure.
 
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