RE: [CAD_CAM_EDM_DRO] Re: how the heck to peck

Been there done that. Years ago I converted a harbor freight drill press
to cnc using a cheap harbor freight 5" xy drill cross slide. For the Z
axis I removed the handle and bored a 60 tooth timing belt pulley to fit
the cross shaft. I used a 12 tooth timing pulley on the stepper motor. I
would use at least a 210 oz in motor. If you use G code you can do a
peck cycle and drill to your hearts content. I'll look to see if I have
any pictures around.
Dan

-----Original Message-----
From: dave_ace_me [mailto:davemucha@...]
Sent: Wednesday, December 05, 2001 1:43 PM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: [CAD_CAM_EDM_DRO] Re: how the heck to peck

Hi Jan,

I have already figured out how to do the X Y so that part is not too
tough. There are a lot of ways to do the table movement.

So I am going towards a full CNC machine.

Since the tiny drills will be in aluminum or plastic (PVC)
moving the parts is the easy part.

In PVC, the drills bind if the material gets hot and there is heck to
pay with a stuck drill. in aluminum, the chips mess with the lip of
the hole. In aluminum the peck is to keep the entrance hole sharp,a
nd in PVC it is to keep the bit cool enough to eleminate melting.

Since I am using a PC to move the parts, I can control the motor
actions.

Seems like a chain will be the easiest to do now as I can get that
pretty easily, and a smaller stepper would offer more torque when the
gearing is used. I'm sure that chain wear will throw some curves
down the road, but it may not be too bad of a problem.

Since I'm doing through holes, there is no problem with depth.

I'll be more than glad to hear any other suggestions or maybe some
links to what has been done.

Dave