I have been struggling with the simplest of things lately, I was having trouble finishing some of the last set of the infamous coasters! As you know I have been raving about the Ceramithane WB finish and how good it is etc. Well on these coasters I was having rubbing out the finish without rubbing through the finish! I tried so many things and was getting realyy frustrated, however I thought through what was different this time and I am sure it was the fact that I did not use the hydrocoat pre-sealer that I have used on everything before -
http://www.tools-for-woodworking.com/index.asp?PageAction=VIEWPROD&ProdID=1243
For these coasters I ran out of the sealer so went straight for the finish. It seems that by doing this, the water in the finish warped the wood slightly and so is not flat. When I put a straight edge across the top I found approx 10thou dip in the middle and obviously the opposite on the back. So by rubbing with a sanding block I was always stopping before the finish in the middle was rubbed out because I was rubbing through at the edges. Long story short - Always use a pre-sealer with WB finish even if you pre-wet and sand to get rid of the raised grain.
http://www.tools-for-woodworking.com/index.asp?PageAction=VIEWPROD&ProdID=1243
For these coasters I ran out of the sealer so went straight for the finish. It seems that by doing this, the water in the finish warped the wood slightly and so is not flat. When I put a straight edge across the top I found approx 10thou dip in the middle and obviously the opposite on the back. So by rubbing with a sanding block I was always stopping before the finish in the middle was rubbed out because I was rubbing through at the edges. Long story short - Always use a pre-sealer with WB finish even if you pre-wet and sand to get rid of the raised grain.