finishing mikarta

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I made some blue jean mikarta and just put it on a knife. Damn its ugly. What do I finish it with that will allow polishing. I was thinking of using polyurethane.

A pic for to get the idea.
 

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i like to take mine to about 400 grit hand sanding then light coat of super glue then sand it down lightly to smooth the finish then buff
but thats just me and my home made mycarta
butch
 
Thanks guys. Nobody uses spar urethane? Is Mikarta waterproof? I made mine with West Marine System epoxy and wife's blue jeans.
 
Do a search for Ariel Silvierra's posts. Many great tutorials, including many on mikarta.
 
I don't know what everyone is using for pre-preg on you material, but I'm told that polyester resin (like that used on surfboards) rather than phenolic resin is the way to go because it doesn't turn your died colors so much darker (not so much of the wet look).

Common epoxies tend to be softer and will result in material that is harder to finish.
 
I used the west marine epoxy resin. Great system, but lotsa $.
 
aproy1101 said:
I used the west marine epoxy resin. Great system, but lotsa $.
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Does this resin get really hard? I think you want it really stiff and thin so you get full saturation so the material is of pretty uniform hardness throughout. Otherwise the material's texture will be more pronounced.

I think a useful way to get 'blue jean' micarta is to use stone-washed denim of a much lighter weight than that used on actual blue jeans and use a thin polyester resin that'll get real hard. Finish as you want then bead blast it to even out the 'sheen' and give a uniform matte finish.

It's really important to ensure full penetration of your resin into your cloth, or you get irregularity and worse--fuzziness. The pros saturate the material and run it through rollers to ring out excess resin and squeeze it through the fibers before laying it up and pressing it together.
 
heres a pic of some i just got done
also yes jeans take lots of epoxy to saturate
DSC02571sm.jpg
 
Yes, it took a lot of resin. I wound up with a blank ~3/8" thick. The cloth was certainly saturated, and the resin is very hard. I also did some canvas that day, but haven't used it yet.

BB, dang beautiful work bro. Really beautiful. Superglue huh? Can't argue with those results. Thanks a bunch!
 
need to make sure its smooth before the glue and
the glue sorta gives the wet look (darker) but then you jsut let it dry and sand a little more then buff
 
One problem with home brew "Micarta" is that it is not Micarta. It is resin impregnated cloth. It won't buff up like the phenolic in micarta. The resin should be polished the same as if you were refinishing a boat or a Corvette. Sand very smooth,using wet carborundum paper to the finest grit possible. Buff with a fiberglass/plastic polish and a clean soft cloth. The trick is to use the hardest resin possible and cure it under the best conditions, in the beginning.Once fully cured, don't do anything that heats it up much,like sanding on the 2X72 at high speed.Power sand on slow speed to 120 grit and switch to hand sanding. Switch to wet sanding at 400.
 
aproy1101 said:
Thanks guys. Nobody uses spar urethane? Is Mikarta waterproof? I made mine with West Marine System epoxy and wife's blue jeans.
Click to expand...


Is it waterproof? You made it with west system MARINE epoxy, What do you think? (Hint, there's a clue in the second sentence)
 
JCaswell said:
It's really important to ensure full penetration of your resin into your cloth, or you get irregularity and worse--fuzziness. The pros saturate the material and run it through rollers to ring out excess resin and squeeze it through the fibers before laying it up and pressing it together.
Click to expand...

I think you make a very important point, Mr. Caswell. It also effects how waterproof it is.

I was given a "fuzzy" piece of homemade bluejean micarta once. It seemed to want to take up water. I weighed it, then set it on end with a little water in the bottom of a glass. The water wicked all the way up the laminate, inside and out. It gained nearly it's own weight in water and took forever to dry out completely.

The cause was insufficient penetration of the fabric by the resin.
 
fitzo said:
I think you make a very important point, Mr. Caswell. It also effects how waterproof it is.

I was given a "fuzzy" piece of homemade bluejean micarta once. It seemed to want to take up water. I weighed it, then set it on end with a little water in the bottom of a glass. The water wicked all the way up the laminate, inside and out. It gained nearly it's own weight in water and took forever to dry out completely.

The cause was insufficient penetration of the fabric by the resin.
Click to expand...

WOW.
I suspect if it'll soak up water, you could get it to soak up something else that's thin enough.
Ideas that come to mind include:

Sending it out to get stabilized (as strange as that might seem.)
Soaking it in penetrating epoxy, wood hardener or even very thin resin.

It kind of stinks that these things tend to become obvious AFTER it's already on a knife.

What did you do with your thirsty micarta? Try any fixes?
 
most likly it was pressed to hard and squeezed too much epoxy out
kind of tricky to get right i have trashed some because it just didnt turn out right
 
JCaswell said:
What did you do with your thirsty micarta? Try any fixes?
Click to expand...

It never made it onto a knife. The texture of the material made me suspicious of it "waterproofness" (technical term is hydrophobicity, if anyone's interested). I dripped some water on and the surface layer sucked it up. I then ran my little weigh/water wick/weigh experiment. Informed the maker, he changed his process to ensure saturation, and he replaced it. Never did try anything. I don't even remember if I still have it; it's been a few years.

I think you have a very good idea there with the secondary treatment. It would be desirable if these materials were hydrophobic. Heck, even the corn cob handles were. :)

Do you mind if I ask you what "J" stands for. Is it Joe, as in the "Moto-Joe" I gleaned from your website? I prefer not to keep calling you Mr. Caswell, if you don't object. Seems too impersonal. I would also ask what style of guitar playing you cotton to most. :) I am mostly a blues player. I just got to play my Tom Anderson Hollow-T Tele for a couple days until this &%^$&^% bad hand gave out. Wonderful guitar, always a pleasure.
 
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