First attempts at worthless wood. need some advice

[keithy]

Hi All,

I have been slicing some yellow box burl into pen blanks.

I have several pieces that are almost full length blanks but are only half thickness with the side that is missing having lots of what look like mountains poking up from the rest of the wood.

I have thought to place them into my 3/4 square mold from PTsubbie and fill the mold with blue PR to make what I hope is an interesting blank.

I normally stabilize yellow box blanks with cactus juice (uncolored) as they are full of voids and cracks. I thought that if I do that with these pieces then the PR infill might not a) adhere well and 2) The excess cactus juice that runs out during cure would sort of fill the valleys and stop the colored PR from making contact with the wood and then when I turn the blank it will look a mess.

Should I just cast the wood in the PR an hope that it will turn OK as the PR might seep into the wood a bit

Any advice appreciated

Keith

 

[SDB777]

Pressure is your friend with burl caps and resin.....



Scott (others will be here soon) B

 

[JohnU]

I believe I read a post by Curtis once that said to cast then stabilize but I think it was in reference to using alumilite. I would expect PR would get brittle if heated in oven during stabilizing. If you just have cracks and the wood is not punky, I would just cast. You can always fill cracks while turning.

 

[robutacion]

Well, you have to consider a few things as follow;

If the pieces you want to cast are are not perfectly dry, stabilizing and casting wont give you good results, put the wood in an oven at 70 to 90° Celsius for at least 24 hours before you stabilized them.

When you stabilized wood pieces that have lots of burl, crevasses, etc., the only way you can avoid the Juice to cure in places you don't want and create a dry/crust skin that will interfere with the casting quality is to, cure the wood without being wrapped in foil and position the wood with the burl spikes down so that, the excess juice runs into a tray instead of staying in the wood. In normal blanks, that excess dry juice can be sanded without compromising the shape of the wood but with the wood type you are intending to use, this system works well, you only have to remember that, you need a tray (normally part of an oven or, make something with foil that will hold the dripping juice and not get into the heating elements as that, can create ignition and you can start a fire. (this is particular true if the oven is set with much higher temps then recommended).

Using Polyester resin, you will never have as good adhesion (wood & resin) as Epoxy or Alumilite so, I would suggest you keep that resin for making only acrylic blanks as use Alumilite for your castings.

There will be problems if you stabilize after casting with PR, the heat necessary to cure the resin will make the resin supper brittle and in most cases will separate from the wood (exceptions do apply) so, I always stabilise and than cast.

Remember that pictures, are a must...!

Good luck.

Cheers
George