Another Mortiser Question

[MBG]

I too got a deal on the hit/miss Delta 14-651 hollow chisel mortisers (got two to make one working one).

So far I have just made sample cuts with the 1/2" chisel in a 1" thick piece of oak. I originally had burning problems and even stalled the motor a couple of times until I found out if you adjust the bit by allowing a 1/16" to 3/16" gap between the chisel and bushing it doesn't give the correct clearance between the bit/chisel.

I bought a set of chisel cone sharpening stones and sharpened the 1/2" chisel. I also cleaned the outside of the chisel with some diamond stones I have.

I have read on other forums that this thing cuts the wood like it's butter. Maybe they are using the smaller chisels?

Even after sharpening I still find that it requires quite a bit of force to make a hole - is this normal????

Thanks,

Mike

[Ken Weaver]

The 1/2" bit is the hardest to use because it is the largest. More force required because you're chiseling more. The best trick I've found is to take smaller "bites" and give the bit time to clear itself, pulling the bit completely out of the work at times.

[MilDoc]

Completely agree with Ken. Found the same. You have to let the bit clear and take sometimes very small bites.

[MBG]

I gave it another try. I used a nice square piece of lumber and it cut much better.

I think my problem was that my trial piece was a rough sawn piece of oak....so it wasn't totally flat at the back or bottom and caused the workpiece to shift and put side load on the chisel.