Liquid Inlay Technique

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hanselcj
Posts: 96
Joined: Tue Apr 01, 2014 9:57 pm
Location: Central Florida (east coast)

Liquid Inlay Technique

Post by hanselcj » Wed Dec 17, 2014 1:19 am

I have tried a number of techniques in an attempt to find a good method of liquid inlay. Let me start with an example:

Image

Mill out the text, and instead of filling it with wood or another material, you paint something in.

I have made a variety of posts on my blog that mostly capture my shame and failure. I will summarize my successful results here so you don't have to dig through everything. There are lots of pictures and detail explanations for those interested.

Liquid Inlay Failure
Inlay Experiment Part 1
Inlay Issues Part 2
Success!

The winning recipe seems to be the following:
  • 1. Mill out text or design to around 0.05". You will see the whole shape of the pocket, so round or vee bottoms could be interesting.
  • 2. Seal wood with spray lacquer. It can be found at hardware stores and is cheap. You don't need much, just a light coating.
  • 3. Mix acrylic craft paint with water to thin, and coat all inside surfaces of the pocket. Leave to dry overnight
  • 4. Sand off surface to remove any paint that remains on top surface. A hand plane does a really stellar job here if you have one.
That is it, the spray sealer keeps the paint from wicking down the wood grain, and once you sand the excess off the top surface things look great. I forgot the spray lacquer in the picture above, and you can see some bleeding in the red text. For those interested in filling the pocket completely I would recommend Inlace brand filler. They make all different colors, sparkles, metal effects, textures and things that make it look like rock. The products are kind of expensive and difficult to come by though.

My other failed experiments included different dying techniques in both two part epoxy and polyester resin. That and I tried to completely fill the pocket with acrylic paint, then sand smooth. It shrinks waaaay too much. Now get out there and make some holiday presents!
Shapeoko 2 #4951: Xbox 360 Pendant, Z-axis lead screw and NEMA23 upgrade, DW660 with Loc-Line dust collection, Googly Eyes, Swivel cutter attachment.

RobCee
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Location: Birmingham, UK

Re: Liquid Inlay Technique

Post by RobCee » Wed Dec 17, 2014 9:26 am

Excellent information there. This lines up with my findings from other woodworking/infill investigation that I have been looking at. The critical element is sealing the wood in and around the paint, so that it cannot bleed out into the grain.
Have you tried using a card scraper instead of a plane for clean up? It is much less aggressive, but is able to flatten out areas like the raised paint very easily. The best part is that they are inexpensive! Although they can be a bit tricky to learn to sharpen, but luckily the internet is your friend.
ShapeOko2 #3400 - Chinese 800W AC Spindle - Stiffened X-Axis - TR10 Z-Axis - Inverted Z Motor - Hall Effect Limits - Drag Chains & Custom Brackets

ootwninja
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Re: Liquid Inlay Technique

Post by ootwninja » Wed Dec 17, 2014 10:57 am

I'm having pretty good luck with epoxy as a filler. Using West System #105 with the extra slow hardener, #209. Adding a bit of #406 Colloidal silica filler helps with shrinkage. Pigments I use are "Slice of the Moon". It's a powder blended with the epoxy so it's less likely to run and I use a syringe to get the epoxy where I want it.

hanselcj
Posts: 96
Joined: Tue Apr 01, 2014 9:57 pm
Location: Central Florida (east coast)

Re: Liquid Inlay Technique

Post by hanselcj » Wed Dec 17, 2014 11:34 am

RobCee, I have cabinet scrapers, but am not that good with them. I have however, gotten pretty good with my smoothing planes and can take a really thin shaving. I almost never sand anything anymore!

ootwninja, that is more complex than I had gone. I used a castin' craft liquid dye. It seemed to really darken the resin/epoxy, but badly effected the hardness and adhesion of the filler. At this point, the acrylic paint trick is so fast easy and cheap that it is hard to try anything else.
Shapeoko 2 #4951: Xbox 360 Pendant, Z-axis lead screw and NEMA23 upgrade, DW660 with Loc-Line dust collection, Googly Eyes, Swivel cutter attachment.

megeshg
Posts: 91
Joined: Sat Mar 22, 2014 6:08 pm

Re: Liquid Inlay Technique

Post by megeshg » Wed Dec 17, 2014 2:02 pm

ootwninja wrote:I'm having pretty good luck with epoxy as a filler. Using West System #105 with the extra slow hardener, #209. Adding a bit of #406 Colloidal silica filler helps with shrinkage. Pigments I use are "Slice of the Moon". It's a powder blended with the epoxy so it's less likely to run and I use a syringe to get the epoxy where I want it.
do you have samples of this technique? I would like to do this but in aluminium.

criznach
Posts: 220
Joined: Sat Dec 14, 2013 5:28 pm
Location: Great Falls, Montana, USA

Re: Liquid Inlay Technique

Post by criznach » Wed Dec 17, 2014 4:01 pm

I've had some luck tinting epoxy with hobby enamel paints. I read about it on a forum somewhere and I haven't had any problems. I fixed a tail light with a translucent red tint about a year ago and it's holding up well even with the outdoor UV levels. Might be worth exploring more.

halfnormal
Posts: 227
Joined: Thu Nov 21, 2013 6:44 am
Location: Flagstaff AZ

Re: Liquid Inlay Technique

Post by halfnormal » Sat Dec 20, 2014 12:03 am

The subject got me to thinking about the different colors of wood filler they offer. There is a white one that I wonder if you could color?
I would think it would bind well to the wood and sand well too.

hanselcj
Posts: 96
Joined: Tue Apr 01, 2014 9:57 pm
Location: Central Florida (east coast)

Re: Liquid Inlay Technique

Post by hanselcj » Sat Dec 20, 2014 1:41 am

halfnormal, It is possible. The issues you would probably run into are mixing the colors in well enough, and adhesion. Even a small amount of dye can really mess up an epoxy's ability to cure correctly and bond to surfaces. It would probably take a decent bit of mixing to get the color integrated evenly. All that having been said, give it a try! Nothing to lose.
Shapeoko 2 #4951: Xbox 360 Pendant, Z-axis lead screw and NEMA23 upgrade, DW660 with Loc-Line dust collection, Googly Eyes, Swivel cutter attachment.

cvoinescu
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Re: Liquid Inlay Technique

Post by cvoinescu » Sat Dec 20, 2014 2:30 am

There's also the fact that the white filler probably has a lot of white pigment in it, so you won't be able to color it in a dark and/or saturated color.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

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