Replies

1. 
   RANGERP75R | Nov 26, 2002 08:45am | #1

   RJ

      The first thing I would check is the moisture content of the pine. Throw a moisture meter on it and see if it is above 13%. If you don't have one, try a piece of stock with the mortiser that has been sitting in a stable place in the shop for awhile. Preferably oak or some hardwood. See if you get a different result with that piece of known drier stock.

      The pine is not an ideal thing to be using with a mortiser. If it's wet, the results with gumming are greatly magnified. This is where I would start looking for the solution. If that doesn't cure your problem, then look elsewhere. BTW, shoot a dab of Pam on the bit and chisel and see what happens.

   Good luck..

   sarge..jt

2. 
   ChipTam | Nov 26, 2002 02:31pm | #2

   Sarge may be right about the high moisture content in the pine which you're using.  I would also make sure that the bit is at least ( and perhaps a litle more than) 3/16" lower than the chisel.  Also, make sure that the opening in the chisel faces to the side. 

3. 
   HowardAcheson | Nov 26, 2002 06:35pm | #3

   Pine, particularly if it is not fully dry, can be a problem. It is very resinous therefore sticky.

   Here are a couple of suggestions for machine mortising. First, to assemble the chisel and bit, first insert the chisel into the quill and use the edge of a quarter to keep it from fully seating. Tighten the chisel into the quill. Insert the bit into the chisel as far as it will go and tighten it in the chuck. Now, go back and loosen the chisel and fully seat it. This creates the correct clearence between the bit end and the chisel.

   Another thing to do is the hone the four edges of the chisel(s) to the same degree of high polish that you would for the backs of your bench chisels. Use the same honing schedule and stones. This will allow the chisels to more easily enter and leave the wood.

   Finally, take small bites and raise the chisel frequently to let the accumulated chips clear the chisel.

1. 
   RANGERP75R | Nov 27, 2002 06:03am | #4

   Howie

      Thanks for the tip on a method to get the bit and chisel positioned properly. I get to the same destination, but had no systematic way to arrive. I've only had a mortiser for 5 or 6 months. This is a clever, very useful tip as I ran down and tried it. I like it as it works and you don't waste time on un-marked side roads.

   Regards..

   sarge..jt