Bolduc Block - Bit Size - Torque

[JIMRPT@aol.com]

In a message dated 18/06/03 5:33:22 PM, jrpiano@win.eastlink.ca writes:

<< The speed you drill at has an effect on the size of the hole, one way the

hole is larger, the other smaller, with the same size bit.

I forget which is which, but too fast is no good and neither is too slow.

Possibly someone can remember the speeds that should be used. >>

John..... you are in agreement with my thoughts here. There are many 
variables as to the answers and among them are, speed of drilling (not only rotational 
speed but vertical penetration speed), sharpness of bit, type of bit (shape 
and structure of point), single pass/double pass, type of block being drilled, 
whether bit is cooled frequently, etc., etc.

 In my experience the slower you drill a hole the larger the final product 
with a faster drilling speed producing a smaller hole...but that is just my 
opinion and is backed up with no objective evidence.

 I drill my blocks with 600/800 RPM and use a .250 bit for 2/0 pins. This 
works very well on multi-layer blocks as well as S&S/Bolduc type blocks. Single 
pass, two insertions per hole. With this combination, and the use of pin 
driving fluid, I end up with very workable chipping/tuning torque values which 
settle down to a very nice 'regular' tuning value. I believe personally that values 
of over 150 are overkill not to mention counterproductive.....but that is 
just my opinion.
Jim Bryant (FL)