Finish for clear glass

[kiltedcelt]

I'm about to get started on a Bingham kit for a "pronounced" t/d longbow. I got clear glass going over walnut lams and a walnut riser. In the instruction manual, it mentions something about sanding off the glossy coating? It mentions this because they say the coating will prevent finishes from adhering properly. If you sand the outer surface of the glass what grit do you use and how to you get it back to a glossy polished looking state? The walnut I'll be using for the riser has got some cool, wild-looking grain. In the past I would've simply finished walnut with an oil finish like tung or linseed. However, I don't know if either of those products would even adhere to the glass. I have a product called Bioshield Hard Oil that I've used on all-wood bows and it's a combination of linseed, tung oil, colophonium resin, castor stand oil, isopar, lead free dryers, and oximes (anti skinning agent). I like this product because the VOCs are extremely low - below 250g/liter. It says the product is a breathable elastic coating with superior water resistance. I suppose I could always finish the riser with the Bioshield and the limbs with another product. Anyway, how do I finish the limbs in order to maintain at least a satin finish and also (obviously), still see the grain?

[jsweka]

You can sand the clear glass with 220 or finer grit sandpaper.

I've always simply used 6 or more coats of a wipe on polyurathane on my bows and have been pleased with the results.  Once the finish hits the sanded glass it will be back to a polished look.  I like the wipe on polyurathane because I can wipe it on, wipe off the excess, and not get any runs.  Many light coats works better than a few heavy coats.  Don't worry you will see the grain.

The only problem with clear glass over a dark wood like walnut is that you will sometimes see light streaks when finished.  These are imperfections in the clear glass and are only cosmetic.

Good luck and post some pics when you have it done.

John

[Trux Turning]

After your glue up you can lightly sand the glass. A spray or wipe on poly will work well on the glass- I usually use tru-oil on the riser and sides of the limbs and then spray the whole bow when I'm happy with the oil finish. The dark woods do tend to show any streaks/imperfections in the glass- make sure you heat your glass and lams up prior to the glue up as this tends to help.