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View Full Version : Epoxy inlays - advice please



Jackson
20th October 2006, 10:36 AM
The attached photos show a technique I'm experimenting with at the moment. I'm trying to create coloured inlays on turned pieces using epoxy. The pattern is created by turning/carving a recess then filling it with epoxy I have coloured. Once dry I finish the surface with tools ( a gouge in this case) then sand and polish. I think this could potentially look pretty good, however I have problem.

Once I start to sand the piece small faults appear in the surface of the epoxy. Picture 1 is an overall shot of a bowl I recently tried. Picture 2 is an overhead shot in which you can see the faults I'm talking about. The faults are the small faint blothches in the red area.

I think the faults may be tiny air bubbles in the epoxy, but I don't really know. I'm sure many have tried this technique successfully before me so I'd be grateful for any assistance or advice others may be able to offer.

Oh, and the bowl is camphor laurel approx 20cm in diameter. The epoxy is just techniglue two pot which has been coloured with rosewood stain.

Cheers

Skew ChiDAMN!!
20th October 2006, 10:58 AM
Could it be patches of unevenly mixed resin?

soundman
20th October 2006, 11:07 AM
you are probaly better off with casting resin or pouring laquer type epoxy.

normal glue types are designed to hold up & not sag (much:D ) therefore bubles will not come out as easily.

casting resins and pouring laquers are expected not to have flaws in the so.....

also mixing method is important..... a folding method rather than a beating method that entraps less air.

just my thaughts.

Wait for dai sensai to pop in he's the resin guru.

cheers

Jackson
20th October 2006, 02:19 PM
Skewie - it could be.

Soundman - I was using the glue instead of a pouring resin so I could fill the rebate a little proud. I think if I use a resin that could be poured it wouldn't fill the whole rebate, especially on a sloped surface. I also want to use this method on spindle turned objects. Do you know if you can get proper resins that can be used in those applications?

Also.., how do they behave when worked witha chisel. The techniglue is great.

Cheers

TTIT
20th October 2006, 04:06 PM
For your spindle idea, my brother used to use pour-on resins in making game-fishing and surf rods but they were placed in a rack of very slowly rotating rollers until the resin set. For items like the one in your pics, you might try blu-tack to make a dam wall to hold the resin in place - has worked for me. You could even try just doing a section at a time and maybe varying the colors.:)

rsser
20th October 2006, 04:34 PM
... side comment: that's a nicely figured piece of Camphor, Jackson.

It's a taste question but for myself I wouldn't try to gild such a lily.

soundman
20th October 2006, 06:57 PM
The cleer acrilic casting resin works just like acrilic pen blanks I supose:confused:

I've seen some masive craters & holes that neil has filled and turned.

you realy need to be filling when you have some more turning to do.

I'd leave the blue tack in the office, it mongrel stuff can cause finish and glue adherance problems.
clay or flour water dough would be fine.

cheers

javali
20th October 2006, 08:16 PM
You can 'break' the bubbles by using a small propane torch. Hold the torch about 15 cm from the surface, and sweep it rapidly over the epoxy. Do not heat a single spot for too long as it may scorch the surface or burn the epoxy.

There is an article about epoxy inlays in FWW.

Jackson
20th October 2006, 09:15 PM
... side comment: that's a nicely figured piece of Camphor, Jackson.

It's a taste question but for myself I wouldn't try to gild such a lily.

You're right Ern. I got this from a fork in the tree and it looked beautiful just plainly turned and polished. However I started this experiment because of a couple of faults in the piece. (If I ever pick that bloody detail gouge up again just shoot me). I strategically photographed from angles that would hide my shame!!!

dai sensei
20th October 2006, 09:37 PM
Wait for dai sensai to pop in he's the resin guru
Thanks Soundman.

I'd agree casting resin is best, but I have seen plenty of good results with epoxy. On curved surfaces you can do a number of pours, a bit at a time, or build wells using blue-tack or plasticene (spelling?) from your local $2 shop. Just cast the resin before final finishing as the plasicene can affect surface.

Before turning, sand/grind down the larger lumps, I use my dremmel, otherwise it can fracture deeply (but you can always recast). Fast speed on the lathe with very light cuts.

Another trick is to heat the resin before you start, it gets really runny, but also sets faster, so you can rock the piece until it sets to cover more curved area.

Cheers

hughie
20th October 2006, 09:48 PM
I think the faults may be tiny air bubbles in the epoxy, but I don't really know. I'm sure many have tried this technique successfully before me so I'd be grateful for any assistance or advice others may be able to offer.


Mark,

Dunno if this will work but a few years ago I used to be involved with casting silicone rubber. To remove the bubbles we used to place the mold in a vacuum chamber as it set for around 5-10 minutes. It worked fine in removing all the bubbles from the setting rubber. There are a number of venturi devices...or were that can be attached to a garden tap to produce a vacuum. It will produce enough for what you want, seeing you come from Cairns it should not be a problem. Here in NSW they banned them several years ago.

I think Hickory has made one out of fridge compressor, have a word with him.

I take it your using epoxy two pack set up that generates heat, so try placing it a cool environment it will slow down the setting speed.

KRH
21st October 2006, 06:55 AM
Agree with most posts. I have had success with the following process:

1. Build a small dam around area to be filled. I simply use masking tape eg a few parts of a mm high, but I only cast on flat surfaces - yours may need to be higher.

2. Use a good thin resin eg West System etc, used in the marine industry. The basic resin is very thin and you add different additions to make glueing and filleting mixes.

3. Use artists paints as an addition to get the colour you want These are very pigmented so not much is required.

4. Use a warm glass jar or such to mix the resin. This lowers the mix viscosity.

5. Pour the mix into your work.

6. Use a hair dryer to GENTLY blow hot air over the mix for a few minutes to assist with raising any bubbles.

Bubble should rise to the surface and provided they are tiny they sould be abve the final finishing level of your work. If larger bubbles are evident then "prod" these to break them down into smaller bubbles or move them to the side.

It works for me, but note that I have only worked on flat surfaces (eg box tops)

Good luck.

Ken

Touchwood
24th October 2006, 12:50 AM
6. Use a hair dryer to GENTLY blow hot air over the mix for a few minutes to assist with raising any bubbles.

a drinking straw and blow throw it - this will also work BUT be aware of saliva dripping off the straw. A straw gives good localised air, popping specific bubbles / areas.

JD

OGYT
24th October 2006, 11:33 AM
I mix epoxy with crushed turquoise and brass key filings, and a lot of the time I get some tiny bubbles, but if I heat it up a little (old hair dryer) after I get it poured (a little proud) in the void, any bubbles tend to come to the top... especially if I tap rapidly on the piece. I use the kind that's in a dual tube that you have to mix, that sets in one hour. Stir it gently, don't fold bubbles into it.
After it's set, I turn it up pretty fast, and use an old HSS cutter that I found in some junk... (must be M4 or something, 'cause it cuts better than M2) and take very light cuts til I get a fine wisp of wood, and then I sand the hound out of it.
May not be the right way... but it works for me. :o