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srwtlc
10-30-2003, 11:54 PM
I have a design that I would like to v-carve into a tabletop and fill in with a colored filler. Has anyone done this? Is there a colored epoxy that would work for this that could be sanded flush and then sprayed over with conversion varnish? What about color bleed into wood grain? If sealed first with conversion varnish, will the epoxy adhere well?

Thanks
Scott

rgbrown@itexas.net
10-31-2003, 05:39 AM
Scott,

I would proceed this way:

I would cut the design into the top ~0.10 to 0.20 deeper than I wanted as a final.

I would brush a coat of "clear" epoxy into the letters, let cure or partially cure, fill the letters with the colored epoxy and then surface, sand and finish.

If one picked the right epoxy, colored filler and top-coat it would be fairly straight forward. But, there can be problems with epoxy and certain finishes. And there can be problems with epoxy bonding to certain rare woods and even problems with epoxy bonding to itself. No one can do your homework on that part without all the information and even then, they can't make sure you measured all the components right and followed all the procedures.

Good luck,
Ron

rookie432
10-31-2003, 08:10 AM
RON & SCOTT,

Check with your local corean or solid surface distributor. They supply liquid epoxies that match all the colors of their solid surface materials. These are acrylic based so sanding and polishing would be no problem and you can get some really neat stone like finishes. As for holding into the wood , cut your vee pattern then take a small drill bit and drill random holes into the vee cut. When you pour your liquid epoxy these holes will fill creating hold pins.

Bill

waynelocke
10-31-2003, 09:49 AM
I think that Fine Woodworking magazine had an article about just this process some time in the last 15 years or so. You might check their index on their website. I think that one of the problems the article mentioned was air bubbles coming to the surface while curing. I don't remember the solution but there was one.
Wayne Locke

kerrazy
10-31-2003, 10:28 AM
I know the air bubble problem only to well.....
You can remove them with a quick light pass with a propane torch.
The reason they occur is the epoxy when mixed causes a catalyst creating enough heat to cause a fire if mixed in large enough quantities. as it cures this heat cause would to expand allowing air to escape from the wood surface and getting trapped in the epoxy. by heating the sursace of the epoxy you reduce the surface tension and the air escapes.

use gentle sweeping strokes not holding the torch in one place to long as it ponly takes a bit of heat for this process to work.

Another method I have heard of is spraying a light mist of denatured alchahol on to the surface and this is suppose to perform the same trick.

If you seal the surface first with a laquer sealer than this can all be avoided.
Dale

artisan
10-31-2003, 10:59 AM
You can also seal the surface with Minwax Polycrylic before you pour your epoxy and be aware that it's actually the carbon dioxide in the flame....Not the heat from the torch that causes the bubbles to break. Touching the surface with the flame can discolor your work, so move it quicly as Dale suggested. Breathing or blowing on the epoxy works just as well for small areas....D

bjwat@comcast.net
10-31-2003, 11:20 AM
You can also spray silicone on your uncured resin to release the suface tension and watch the bubbles rise and crash to the top...I do this all the time with liquid plastics.

Something like 2300 spray from PolyTek works well.

-Brady

artisan
10-31-2003, 11:34 AM
Brady, I don't know if you've ever tried silicone with epoxy before....but they are arch enemies in my experience. I've poured many a bartop that a client had sealed with silicone and had to either remove or coat the silicone with something else first. They react like oil and water and the epoxy will "run away" from the silicone. I'm not sure about the spray....I've never tried it, but a test would be in order I think....D

jkforney
10-31-2003, 12:31 PM
Scott
Another way is the one we have used in my shop for the last 30 years. I use it mostly on shallow inlays upto 3/16 deep. I just use Famowood putty in a color that is one I want. You can also use stain or universal tinting colors to change the color to the one you want. We only use the putty when we are not staining since the putty will take the stain, though if it is enough of a different color it would add some contrast. If the v is very wide and shallow try taking a small drill bit and drilling into the v at an angle less that 90 degrees. This will give you some small mortises in which the putty can gain some purchase.

A color combo we often use is cherry wood with the natural famowood. We find that we usually put one heavy coat, then a lighter coat and then sand and put one finish coat. We also subject it to compressed air to knock any loose parts out on the second coat. The famowood we use is the solvent based and it works fine for us.

Brady
You use silicone around wood finishing? Don't you run the risk of contamination and fisheyes in you finishes?

John Forney

bill.young
10-31-2003, 01:36 PM
Try pouring the epoxy later in the day when the temperature is falling and the wood is cooling... the epoxy will be drawn into the wood instead of bubbles being exhaled from the wood. It's an old varnishers trick that works well with epoxy coating too, especially with porous wood like mahogany.

propellers@aol.com
10-31-2003, 03:45 PM
We daily pour epoxy into wood cavities and have pretty good results.

I would first seal the area you wish to pour resin into and let it set. With pour mahogany it may take two sealings. For best bond and decrease the chance of the letters cracking around the perimeter I would pour the cavity when the resin cures to the point of not deforming with finger pressing into the resin. Over fill the cavity since the resin shrinks a small amount. Then shopbot the surface smooth or sand. If possible make the area or tabletop over thick, do your carving fill the cavities then surface with the bot and a flat bottom cutter and sand. If you get any pinholes mix resin and color with denatured alcohol to thin and wipe into the pinholes.

Choose an epoxy that is very slow to cure. This will allow bubble bursting and flow better. WE find air is whipped into the resin and then the air will expand with degassing and temperature increase of cureing resin. To break the bubbles to the sweeping of the propane torch, several times but be careful, resin cures faster with heat and if you concentrate the heat you will get a cured ball of resin with uncured resin that will start6 kicking off or curing very rapidly. Another way we expell bubbles is to vacumm the resin in a container. Whereas you put your container of resin into a vacumm chamber, this as simple as a box with a vacumm cleaner hose attach so you will suck all the air out. This causes the bubble to increase in size, float to the top and either break or set there waiting for the torch trick.

Pour slowly of down a stick, the resin pouring onto itself with trap air which will cause voids.

Only use epoxy, polyester or vinyester will shrink and will not bond to wood well. Mahogany is oily so treat the area prior to sealing with thinner.

Epoxy colors are available at auto body supply shops or try Fiberglast in Dayton Ohio, do a search on them for their products.

Silicons are a diaster with wood and finishes and a sob to remove on any surface. On repairs we do we wipe all surface with a silicon remover from PPG call DX330.

Check out the decks of Criss Craft boats that are also Mahogany and have the white stipe inlays. I know of one person that tried the epoxy method I suggested above with excellent result

Lonnie Prince

davidallen
10-31-2003, 04:18 PM
many woodworking stores have colored plastic powders for use as epoxy fillers. they're usually sold in the woodturning section. you may also try colored sand from craft stores.

the sand won't machine to the same finish as the plastic, but depending on your desired style and technique, it may be OK.

srwtlc
10-31-2003, 10:19 PM
Thanks for all the info guys. Do you have any preferences on type/brand of epoxy and some distributors?

Scott

rgbrown@itexas.net
11-01-2003, 08:10 AM
I think all of us have preferences on epoxy Scott. I tend to like one brand for bonding wood, another for making stuff with carbon-fiber. If the temperature changes and I can't control my curing enviornment I might prefer a third brand or different formulation from the same company. All epoxy formulators use the same raw ingredients from a very small group of suppliers(I've been told there are only two companies that actually make "epoxy").

Note that Bill Jarvis is using Acrylic. I have no experience working with Acrylic and bonding it to wood.

I know Lonnie and Bill Young have used epoxy. The procedures they suggested indicate the experience is not a shallow one.

If I had a supplier in my home area, I would probably use them.

Ron

Scottmc@diamondcs.net
11-02-2003, 10:22 PM
Ok,
Why V-carve if you can pocket? Or am I missing something here. Will the epoxy hold better? I know that it's much faster to v-carve then pocket(is this why).
Scott

gerald_d
11-02-2003, 10:55 PM
Scott, V-Carving is the only economical way to get fine detail, like the tips of this letter T