Epoxy Questions.

General Discussion
1

Since all the epoxy marketing experts seems to be in this forum I thought I might throw this out.

I need to stabilized some punky/wormy soft wiliwili (hawaiian balsa wood) bits and pieces inorder to drill them out and turn them on a high speed lathe into pen barrels. Its the remains of the dozen or so iolani palace wiliwili tree branches we saved from several years ago so I'm trying to save and use what ever I don't put on the surface of an EPS blank. Most stabilization processes involve an autoclave, high pressure or vacuums and sometype of penetrating acrylic or epoxy solution. Some folks even use a solution of plexiglass chips dissolved in acetone to harden or petrifi spalted soft woods.

Anyway is there a calculation out there as to the effects on kicking of lets say a 70% xylene diluted epoxy mix?

And should you add in the xylene after mixing parts a and b or all togethor?

Also does anyone know who makes the lowest viscosity epoxy on the market before having to add in solvents?

There is some application of this to composite board building as I previously used some low viscosity ResinX epoxies to help with Greenlight bamboo jersey glassing as well as in getting the epoxy or poly finish coats to fall down flat to eliminate brush strokes and bubbles over the cure time but its always a tricky matter of timing so you don't those avalances of resin sliding off the railbands because of miscalculations. 

 

So this led me to this other question that been bugging me for years.

Who's sealing their wood skins before the apply them and how?

there was some talk awhile back (bert rumors I guess) about using some type of penetrating solution (epoxy/acrylic) and an autoclave setup to prebuild the skins ahead of time to reduce the amount of resin absorbtion you normally get doing hand layups over dry balsa.

Silly suggested squeeging a thickened paste onto the outside of a skin prior or applying it on or lamming it after to reduce unneeded resin absorbtion and keeping the weight down on boards with 5mm wood skins and solid wood rails.

when I lift the 2 boards i have from Jarrod (Shwuz) i can do it pretty much with 2 fingers.

Its been ages since I've been able to achieve that kind of weight on any of my compsands,

 

so again, to seal wood skins do you use

1. a standard wood sanding sealer(lacquer/water based),

2. a ultra thinned out penetrating epoxy solution or,

3. thickened epoxy paste?

 

Its funny, that in the small object wood turning world, turners defer from epoxy because they can't get the same brilliant polished finish you can get from the application of 6 or more layers of CA glue. I would never envision CA glue as a finish coat on anything, but the pen folks swear by it.  Maybe this carries over to other applications of epoxy as well.

 Its weird not being able to find application for any of my laminating experience in the finishing of a turned item.

Its also weird and at times frightening to have your work spinning around at 3000 RPM at you while you engage it holding on to a razor sharp blade with your bare hands.

Cutting your planer cord is nothing compared to have your work disintegrate and explode inches from your face.  thank goodness for my full face 3m 6400 respirator

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This is a lot to answer.  We make a low viscosity infusion resin resinresearch.net  Look at the composite pro page.  I’m not sure xylene is what I’d use … let me ponder that till tomorrow. I can look up some stuff too.  I have some info on that somewhere.  I would think that using a very slow cure would give it more time to penetrate.  Also would reduce exotherm which would make the part better.  Give air a chance to settle up too.  Be good to pull a vacuum on it just to pull the air out.  Wouldn’t have to leave it on for more than a few minutes.  

Some of the things Bert talked about were theories that he hadn’t successfully done.  We worked on some skin tech at FW and almost got it to work but it didn’t come out in the long run.  I think that doing veneers can be done effectively without a lot of tricks just by dotting I’s and crossing T’s.  Minimizing resin on every step.

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     Howzit oneula, I want to let you know that you are a true craftsman and I love the presents you gave me and have sent them to the mainland so I can keep on using the letter opener you made and all those DVD's are awesome. To think you go from your desk job to your wood workng side line amazes me and I wish I had the get up and go I had before the cancer thing and what it has done to my quality of life and energy level. I must say that in the last few weeks I have been working with a eastern medicine doctor and have seen some results that are nothing less than great. Last night i actually popped loose a part of my throat that was damaged fromradiation and now it is easier to swallow. I want to once again thank you for being a true brother in the sense of true Aloha an am forever in your debt. Aloha,your friend for ever ,Kokua

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Oneula, give us a ride report when you are done.

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Using a flexible resin is also something that should be considered.  Should cut cleaner that a brittle resin.  2090 with 3100X maybe.  2090 is also the lowest viscosity. 

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Kokua

Thanks for the kind words.

Hope to catch up with you "kauai boys" this summer with some omiyage

Mobi's Hele 3G program  will get to Kauai pretty soon.

Take care of your self.

 

Thanks GL

will diluting low viscosity epoxy by 70% with a solvent like Xylene/DNA make it penetrate directly into the soft wood without getting stuck on the surface and dripping down or does it require vacuum or pressure to get that kind of residueless penetration?

I'll going to use the old compsand trick of heating the object with a heat gun(like leaving your board in the sun) and then applying the diluted resin to the cooling object just like you would  with your wood skinned compsands glassing at sunset to prevent gassing from the resin heated core. I'll also  drill small pilot hole all the way through to get absorbtion from both sides. The only thing I can think of that's similar would be applying your wood shell and exterior glass with perforated peel ply in a bag with a blotter like some of us used to do in the old days before timberflex came about.

 

GT

This weekend I will be making four 8' homedepot multi-density blanks (1" blue dow bottom 2" 0.75lb EPS deck) to glue up with woven bamboo horizontal springers, 1/8" balsa skins and 1" blue dow perimeter rails. Each deck also has a single 3" strip of 1/8" wiliwili down the center which is my new design logo. Basically I'm sticking to these Rarick "versa-plane" 5 fin(4+1) all around designs since they have the widest audience. The blanks will all go into air conditioned storage when I'm done for finishing later as needed/ordered. We also have a couple 2lb 2" wide EPS strip glue ups (8') to finish shaping and timberflexing as well as a couple boards that have been sitting around 75% finished for about a year. A multi-density 8' blue railed all around with bamboo veneer deck and koa veneer bottom and a 4" thick EPS Gemini with a 10 mil bamboo weave bottom and balsa deck. I also have been sitting on a box of 6 sets of bamboo chandler design 5 fins with G10 bases I have to glass for all the other 5 fins I have laying around that are missing a fin or two.

So I haven't quite gone cold turkey of the addiction quite yet.

You gotta admit though 15-30 minutes to create one of these composites will bring as big a smile to its owner.

And everyone, even surfers (maybe not computer swaylockers) could use one of these in their quiver of tools.

 

[img_assist|nid=1052029|title=New Composites|desc=|link=none|align=left|width=0|height=0]

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[quote="$1"]

Who's sealing their wood skins before the apply them and how?

there was some talk awhile back (bert rumors I guess) about using some type of penetrating solution (epoxy/acrylic) and an autoclave setup to prebuild the skins ahead of time to reduce the amount of resin absorbtion you normally get doing hand layups over dry balsa.

Silly suggested squeeging a thickened paste onto the outside of a skin prior or applying it on or lamming it after to reduce unneeded resin absorbtion and keeping the weight down on boards with 5mm wood skins and solid wood rails.

when I lift the 2 boards i have from Jarrod (Shwuz) i can do it pretty much with 2 fingers.

Its been ages since I've been able to achieve that kind of weight on any of my compsands,

so again, to seal wood skins do you use

1. a standard wood sanding sealer(lacquer/water based),

2. a ultra thinned out penetrating epoxy solution or,

3. thickened epoxy paste?

[/quote]

 

Have you looked into Git-Rot for sealing the pens?

I'm not sure if what I do is considered pre-sealing.  I make one-sided skins on a table and apply them to the blank in a seperate step.  On a good skin, the resin almost completely soaks through the entire skin.  By using a wetout table, I can control the fiber/resin ratio.  I have a 15mil plastic sheet, lay the cloth out, saturate the cloth, then lay the planks on top.  Next I tape a top piece of plastic on and pull 25" of vacuum.  I can apply the skin either cloth out or wood out.  I like to use wood out on the bottom and cloth out on the deck.  For the bottom piece, I just squeegee an ounce of resin  real hard onto the skin and vac it onto the bottom.  When I use cloth on the outside, I don't have to glass that side anymore, only hotcoat and gloss (this definitely saves steps on the deck side).  Another advantage of this is pretty much zero resin absorption into the blank.  I guess I use option #4.

If you really feel the need to preseal, why not just squeegee a thin layer a couple of hours before doing the lam?

Also, if you think the boards are too heavy, just back off the resin usage, try to spread as little as possible as far as possible, the regular RR gives you 45+ minutes of pot life, just keep at it.  You may also examine how much glass you are using, try only two layers around the rail, with short laps.

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Oneula, you are so far ahead of me.  I love what you are doing.  Love to see a picture.  Maybe I can figure a way to come out and see all the cool things you and SC are doing.

 

All the best

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bump