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West Systems
Z-poxy
Alraldite glue
Aralraldite clear instant glue
Araldite rapid glue?

How long between applications should I give it before I rub back to the wood?

Thanks

John

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Formerly JJH

I learn more from my mistakes than my successes

Z-Poxy FINISHING RESIN

apply, wait 24 hours, sand, re-apply

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JJ
Napa, CA
http://www.DonohueGuitars.com

In my opinion brand is only important in regards to the color tint of the brand but you will want to use a finishing resin and not a general propose epoxy in my opinion. Finishing resins have a lower viscosity and flow into the pores better. General propose epoxy will work but have higher viscosity and don't flow into the pores as easy. Finishing resins are designed to finish out and level the top layer of fiberglass assemblies prior to gel coating. That makes them great for pore filling as well.

System 3, West system and Zpoxy all make finishing resins.

I've only used WEST Systems. Water clear, or virtually so. 24 hours is a good rule of thumb between filling and sanding back. It also tends to wet out most woods that I've used it on to a greater degree than the finish will, so it's a good idea to make your last session just one where you thin the epoxy out with metho 50/50 and apply an even coat as if you were putting down a sealer coat of shellac. Then just a very light rub back prior to applying your finish of choice.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

John buddy be sure to wear some protective gloves and have ventilation too.

John: Hope you don't mind me jumping in and asking some questions as well. I am currently using System 3 to pore fill. I did one coat, then waited 24 hours, sanded back, and applied another coat. Again, I waited 24 hours and sanded back. I applied a wash coat mixed 50/50 with alcohol.

After the first coat, I thought things looked great, but at the point I am at now, it does not look that great dry, but fine when wet with mineral spirits. I actually sanded back the wash coat quite a bit. The front and back look fine - I can sand these with my ROS, but the sides look cloudy when dry. I had to sand these for the most part by hand.

Should I trust the "wet look" and start finishing or do I need to get things looking more even.

On the wash coat, I thought things would go on easier. I tried to wipe on with some old T-shirt material, but the thinned epoxy was very sticky and did not go on smooth. Maybe spreading with the credit card would have been better.

One comment to add, I have not had the issue that some have with the system 3 not drying well. The guitar seems to dry well and the residual drys hard as well. I let the residual dry in the dixie cup that I mix in. I assume if it has dried hard, the epoxy on the guitar should have dried hard.

So what would you suggest: ready to finish, sand the sides better, or try the wash coat again?

Thanks

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Greg Hatcher
North Carolina

if level then all is fine. you will be adding a seal coat of something, I assume shellac. When you do this the wet look returns. then you lightly cuff the seal coat and it will look dry again then you will apply top coats and it will look wet again then you will level top coats and it will look dry then you willl polish out and then it looks wet

Greg your questions aid my learning to fire away Michael thanks for the speedy reply. Anyone think I can fill the ripples left in the wood and flat back, the deepest of these is 40 thou I tried on scrap building up layers with the cheap thin super glue and accelerator and it looks like gregs description of cut back epoxy.

Cheers

guys

_________________
Formerly JJH

I learn more from my mistakes than my successes

Michael: Thanks for the reply. I sanded the sides again and will begin applying shellac tomorrow.

John: Good Luck with yours.

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Greg Hatcher
North Carolina

This business of needing a gram scale to get the ratios right when using System III epoxy is nonsense. I seem some posts where people claim you need an accuracy in ratio to 4 significant digits. Does anyone believe that a company would market a product that would be so un-user-friendly? Does anyone believe that the original person to make these kind of statements really did enough testing (with all due respects to the original person) to determine accuracy to four places? How many tests would that take?

I use measuring spoons and have never had any problems.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

My method differs in that I want to sand back to the wood leaving the epoxy only in the pores. So I use epoxy glue (5 minute Devcon from the hardware store) and don't thicken. I squeegee hard with a dulled razor blade to force it into the pores; then sand back the next day.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Well Pat my friend there have been at least several post here on the OLF over the years where folks got into trouble with SIII because they winged it with out any precise measurement methodology. They ended up with a gooey mess that would not harden and was a nightmare to remove.

The accuracy level that I used with a calibrated gram scale was accurate to 1/10th of a gram and I had excellent results. Mike Doolin also mentioned this in his toot for SIII and recommended using a gram scale too.

I am happy to hear that you have had good luck with this very fine product that I like too. And I also agree that accuracy to 4 decimal places is overkill. But accuracy to the gram level is what I would follow and when I have it worked out fine for me.

The other concern that I have about SIII and why I switched to West and Z-Poxy is that when I read the FAQs on the SIII site their answer as to the shelf life of the product was not clear but they kind of indicated, cryptically...... that one year ought to be fine....... Personally I need a better answer than this to proceed to have confidence in a product. Especially when the minimum quantities that one can purchase are probably a 3 year supply for a full time guitar builder......

Don't get me wrong, I used SIII at least 6 times and the results were always excellent but then a also used a gram scale and followed the Doolin toot precisely.

And not to be a nag but are you using SIII "finishing resin" and not the epoxy that SIII sells - I suspect that the epoxy glue is more forgiving in mix ratio.

I meant that I don't thin, not that I don't thicken, in my post above.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Hi Howard I'll be sanding back to wood as I'm gonna French polish, I though that epoxy resins were used over glues because of the lower viscosity flowing better into pores. Is it just a time reason you use and apply as you do?

Thanks

John

_________________
Formerly JJH

I learn more from my mistakes than my successes

Doesn't anyone use oil or water base pore filler or pumice for French Polishing? What's the advantage to using Epoxy?

I second Todd's experience with System 3 (Mirror Coat) - with Mirror Coat, it should be noted that 1:1 by volume means 2.27:1 by weight when using a gram scale.

Maybe Mirror Coat is more forgiving than other S3 products - I've been off by 5% and not had a problem.

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The member formerly known as erikbojerik....

Wow doesn't epoxy make the figure it the word really pop! was experimenting did the wenge headstock veneer with superglue and it doesn't have half the effect. Can epoxy go over super glue that's sanded back to wood, as I plan to do a 50%-50% alcohol and epoxy mix Micheal Payne recommended on the final fill and scuff back for even colour he said and would like to do this on the headstock.

Cheers Guys

John

_________________
Formerly JJH

I learn more from my mistakes than my successes

Labor savings, at least of pumice filling. Water based fillers tend to shrink back and oil based I have just never been fond of. But then again I no longer epoxy fill either

I've used Z-poxy and found that watering it down (alcoholing it down) lets it flow better. So I suggest doing one coat full strength followed up with a couple of diluted applications. Also have used pumice with French polish. Seems to work but takes a lot of rubbing. Only thing I don't like about epoxy fill is if you sand through to bare wood you might have to sand the whole thing down to bare wood.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Michael,
Which pore fill method do you use these days?
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Starbond medium thick CA apply like epoxy at 45 degrees to the grain but scrape firmly with a box knife razor blade with rounded corners. Use a fan to blow the fumes away from you and it hardly nay irritant at all. I do use a respirator and goggles. In most cases one session is all that is needed.

I tried medium thin and it sets too quick thin is too runny and hard to control. Medium thick is just right has a perfect open time cure to sandable in an hour to an our and half.

Cost per guitar is about $3.00 more than Zpoxy