Advice on Casting Resin "Faux Wood"

Bradberry00 · Oct 29, 2017

Hey all,

I am hoping to cast some MGC Mauser grips to replace the grips on a couple of my MGCs. I am curious what resin/additives I should use to get a similar outcome to the grips in this image. I am thinking off white resin with pecan flour and pigment but maybe there is a better product...there is that "randomness" in the coloring that I would like to replicate.

any advice would be helpful,
-david

Collektor · Oct 29, 2017

If the grips you're casting already have some sort of wood texture to them, then you could cast the grips using a color that matches the lighter shade of brown on the masters. Then a couple washes of a darker brown and I think you'd be getting the effect you want.

robstyle · Oct 30, 2017

Having myself spent many hours testing various methods and materials to cast wood, my advice, dont. The main reasons are cost and perfecting the batch of material on every mix. The perfect mix will account for moisture in the casting material, the wood dust and the moisture in the air itself. Any one of those is off and the part will expand. Pecan flour is a widely used method to patch boats, again it expands with moisture. To do away with that expansion youll need to bake every batch of wood dust which times vary due to which ever wood dust is used, even pecan flour. The temperature of the mould itself will also effect the part as will any color additives. Again, I did A LOT of trial and error with casting wood.
The casting material is very important as thats where the strength for the part will come from. Generic casting resin is inherently weak and brittle as well as lacking sharpness. I used a high impact plastic only available at one vendor, MPK. Its five times the cost of cheap resin but you get what you pay for with quality casting materials.

Pigment will be your worst enemy, its water based.

Here is an example of trial and error in getting a proper mix. Notice the top row of grips and the bottom right pair. They expanded as there was moisture present even though I knew the exact temp and time to bake the raw wood dust prior to casting. The moisture was in the air so I had to wait later in the day to start again. The pairs center and center right as well as bottom center were the only usable castings. There is no flashing to trim as they were perfect right out of the mould. Again, all temps have to play together to get that perfect casting, material, wood dust, mould, air...

A test casting with a coat of Varathane.

Bradberry00 · Oct 30, 2017

So what products worked best for you? I really have no choice but cast these. MGCs are incredibly rare and finding authentic grips just isn't an option.

robstyle said:
Having myself spent many hours testing various methods and materials to cast wood, my advice, dont. The main reasons are cost and perfecting the batch of material on every mix. The perfect mix will account for moisture in the casting material, the wood dust and the moisture in the air itself. Any one of those is off and the part will expand. Pecan flour is a widely used method to patch boats, again it expands with moisture. To do away with that expansion youll need to bake every batch of wood dust which times vary due to which ever wood dust is used, even pecan flour. The temperature of the mould itself will also effect the part as will any color additives. Again, I did A LOT of trial and error with casting wood.
The casting material is very important as thats where the strength for the part will come from. Generic casting resin is inherently weak and brittle as well as lacking sharpness. I used a high impact plastic only available at one vendor, MPK. Its five times the cost of cheap resin but you get what you pay for with quality casting materials.

Pigment will be your worst enemy, its water based.

Here is an example of trial and error in getting a proper mix. Notice the top row of grips and the bottom right pair. They expanded as there was moisture present even though I knew the exact temp and time to bake the raw wood dust prior to casting. The moisture was in the air so I had to wait later in the day to start again. The pairs center and center right as well as bottom center were the only usable castings. There is no flashing to trim as they were perfect right out of the mould. Again, all temps have to play together to get that perfect casting, material, wood dust, mould, air...

View attachment 769888

A test casting with a coat of Varathane.
View attachment 769889

Bradberry00 · Oct 31, 2017

So researching a bit more I may do translucent white resin with brown pigment and dried out pecan flour. Think this would be a could starting point? Alternatively, how dark does the pecan flour look on its own? could I use just that with clear resin?

-david

robstyle · Nov 4, 2017

Pecan flour, as with most wood dust materials, will come out something along the lines of bland tan with white casting material or too dark black with black casting material. The randomness and depth of the wood parts youre after isnt possible without a combination of color and the casting material used. If the casting material is too slow or too fast in curing the material added to it will sink or swim. I seriously recommend just casting the parts out of tinted material and abandon the cast wood idea. Its just not needed. Yes that sounds defeatist but again, ive done it and I have a decent amount of moulding and casting experience. Everything involved is a learning curve when casting wood. I figured it out through a mass of research, doing boat repairs with friends, weeks of testing various wood dust, baking materials, icing materials, combining casting materials.... Just cast the grips with a decent material. The need vs the want is where youre $$$ will end up.

I use MPK products for casting. The high impact plastic is the best material ive used but again, expensive.

PoopaPapaPalps · Nov 4, 2017

I've only cheated to get a faux wood grain texture in plastic casts (with varying results) but it's typically just a surface detail. The short of it is is that I just dry brush the inside of the mold that I made with various "wood" colors and then just back fill that with resin. Clear coat the surface and call it quits.:unsure

penabled · Nov 4, 2017

I have seen some fairly realistic looking wood stuff created using sculpy and paint to replicate the coloring but I'm not sure it would be an easy task to bake it to hardness once you mixed the colors to your liking. Probably have to do a silicone mold of the grips that could resist the pressure of pressing the clay into it. Maybe a hard casting of the outside surface then press that down onto the clay to form the piece and cut away any remaining clay from it.

Advice on Casting Resin "Faux Wood"

Bradberry00

Sr Member

Collektor

Well-Known Member

robstyle

Master Member

Bradberry00

Sr Member

Bradberry00

Sr Member

robstyle

Master Member

PoopaPapaPalps

Master Member

penabled

New Member

Similar threads