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Rob Price
11-18-2016, 1:20 PM
I'm working on some benches for our kitchen table. I found some really cool 1830's barn beams, hand hewn and lots of bug holes. These are going to be used every day- so they need to be smooth enough to sit on for wiggly kids, and I don't want food/crumbs in the holes. I'm contemplating filling the divots and holes with epoxy and then sanding down to reveal some of the high points but keeping a lot of the character of the wood. I've used the enviro-tex epoxy quite a bit but it's pretty viscous. Not sure it will settle in the bug holes well. A buddy recommended West marine epoxy, says it's much thinner. I thought I'd see what you guys think. Thanks.

I've tried to attach a pic but the app keeps crashing.

Ken Fitzgerald
11-18-2016, 1:28 PM
Rob....epoxy can be thinned by mixing denatured alcohol with it IIRC. Turners make an epoxy cocktail to stabilize punky wood by thinning epoxy and slathering it on.

Do a search on "epoxy cocktail" here at SMC. There are a lot of threads about it.

Simon Dupay
11-18-2016, 1:31 PM
Look at west systems expensive but works very well

John Blazy
11-18-2016, 4:05 PM
I deal with filling voids all the time in my laminates, using a whole host of resins like epoxy, UV cure glue, 2K acrylic etc and use a syringe for filling from the bottom up. I get all my syringes from McMaster Carr with different needles. The large .030" or larger needles will allow plenty of flow to fill your wormholes quickly. You will discover that the epoxy soaks in after ten minutes, so you will need to top off the holes after initial filling. If you don't fill from the bottom up, like the way you planned, the air will trap at the top and you will see the bubble. You can even bend the needles easily to go deep into curved holes.

That way you can get away without thinning the epoxy, however, I have had no problems with thinned epoxy, in a 15% ratio of DNA like Ken suggested. Even 10% will thin it plenty, yet not affect cure or final properties.

Rob Price
11-18-2016, 4:09 PM
Perfect. That's what I was looking for. A syringe makes sense.

Martin Wasner
11-18-2016, 4:28 PM
I would go for Acetone or MEK for thinning epoxy. I've done it with the Envirotech stuff from the box stores. They say not to, but I haven't seen any negative results from doing it.

Applying heat with a torch is what works the best for getting it to settle into the cracks and holes I've found. It warms it up, thins it out, and brings the bubbles to the surface. There's something there too about CO2 helping, but I don't understand it. I just know a torch works much better than a heat gun.

Prashun Patel
11-18-2016, 4:32 PM
A slow-setting epoxy (like System 3), while viscous does a very good job of settling into cracks over its 40 minute open-time. Further, it gives bubbles time escape - provided you do not try to fill deep voids in a single pass. If you fear white bubbles, you can tint it with a drop of black dye which will make it opaque.

You can also heat the components by immersing the bottles in hot water for 30 minutes before mixing. If you don't have to thin, I wouldn't.

Ron Kellison
11-18-2016, 7:21 PM
I like Cold-Cure from Lee Valley. Very thin, dries clear and seeps into every nook and cranny before it sets up. Not cheap but it works well!

Gerry Grzadzinski
11-18-2016, 7:45 PM
I use US Composites. Comparable to West Systems and System 3, at 1/3 the price.

Bill Conerly
11-18-2016, 9:15 PM
On a boat repair, I needed to inject epoxy into a pretty small hole. I put the resin without hardener underneath a 100 watt lamp until it got warm. Then added the slow-acting hardener, stirred a full 60 seconds, and injected with syringe. Worked perfectly.

Rob Price
11-18-2016, 9:51 PM
I see a lot of folks warming it up, I may try that first before thinning. My shop is heated, but I also can put a radiant heater in the finishing booth to warm that room up even more.

Keep the brand recommendations coming, I see several marine epoxies on Amazon I can get shipped free. TotalBoat. East coast resin... I did find a place to get West Systems about 40 miles from here.

Martin Wasner
11-18-2016, 10:10 PM
On a boat repair, I needed to inject epoxy into a pretty small hole. I put the resin without hardener underneath a 100 watt lamp until it got warm. Then added the slow-acting hardener, stirred a full 60 seconds, and injected with syringe. Worked perfectly.

Hobie 16 deck repair?

Jim Finn
11-19-2016, 7:19 AM
I use "Z-poxy" finishing resin to fill voids. It will flow right through cracks so the underside needs to have masking tape applied. Slow to set up, so great penetration. Hobby shops should have it available.

Allan Dozier
11-19-2016, 8:37 AM
I've used West Systems and some others in boat building and it is good epoxy but I think MAS is the Cadillac of epoxies. Their resin is thinner, dries water-clear, and no blush. They also make a thicker resin called FLAG for (filleting, lamination, and gluing). If you want something less expensive but still good, look at RAKA epoxies.

Rob Price
11-19-2016, 12:30 PM
I will probably thin for the worm holes. Nothing structural, just keeping food out. Then I will level with full strength. I found a way to link an image:

https://goo.gl/photos/tvpBU4YRowfBzJQA8

Lon Crosby
11-19-2016, 8:37 PM
Go to a farm supply store for needles and syringes. They exist even in horse country.

Dave Macy
11-19-2016, 9:13 PM
you can tint it with a drop of black dye which will make it opaque
I've never heard of that. What kind of dye, do you have a link? Thank you.

Frank Drackman
11-20-2016, 3:15 PM
I'm not Prashun but I do the same thing with Transtint black dye.

Prashun Patel
11-20-2016, 4:21 PM
Frank, I also use transtint black dye. There are a million other substitutes but a single bottle of transtint black dye lasts forever and is much easier than messing around with the other black tricks.

Mike Henderson
11-20-2016, 9:49 PM
I use a powdered black dye and just mix it with the epoxy. The cured epoxy comes out looking like ebony.

Mike

Rob Price
11-21-2016, 8:12 AM
On a different project I've mixed in really fine walnut sawdust from my sander for a jet black look. I can't remember who it is but one epoxy company sells 'wood flour' to mix in with their epoxy for tinting. Supposedly the wood fibers help the epoxy expand and contract with the wood on big repairs.

I have a bottle of transtint I've used in various finishes. I didn't think about the epoxy. I think for this project I'll stick with clear since it will be hard to sand off any overspilling of the epoxy without really changing the look of the wood. But for your typical fill and sand flat application I'll give it a go.

mark kosse
11-21-2016, 8:14 PM
I use old ink pens to dye my epoxy. Cut the tip off and blow it into the epoxy.