Comments & Questions fo the List

May 11, 1999 - 4:24PM - CDT

1) It's good to know that so many people are interested in this topic -
Hopefully I can get some help in the areas in which I am weak -

2) Re: CNC Router How-To - Gar mentioned the routers that I've built (2) -
However they didn't use rollers on tubes but instead used Thomson NYLINER
bearings which are a very low-cost sliding bearing - I used DOM tubing which
is relatively inexpensive and accurate - I've done a lot of work with
woodworking machinery and chose this method because the tubes can be
lubricated quite successfully with floor wax instead of oil or grease and it
doesn't attract and hold the dust - Also the sliding bearings are self
cleaning - Haven't had any problems and they have been in service for a long
time -

3) Re: High speed spindles - I've successfully used a 20,000 rpm electric
spindle made from a DUMORE die grinder - They are available with collets up
to 1/4 diameter and they are relatively inexpensive - About $300 as I recall
- I am currently working up an air turbine spindle of 40,000 rpm using a
turbine from AIR TURBINE TOOLS, Boca Raton, FL - It too has a collet nose
and will take tools of up to 1/4 dia - This one is also relatively
inexpensive at under $400 - While $300 or $400 is not "chicken feed" these
are the best prices I've been able to find for tools of this quality - For
the CNC Routers mentioned in item 2) above I used PORTER CABLE commercial
routers with collets up to 1/2 inch diameter - Can't remember the rpm but it
is probably in the 15,000 to 20,000 range - As I recall they were less
expensive at about $150 but don't have nearly the quality of the other two
units - Perfectly good for routing wood but not for more precision
applications -

4) Re: EDM users - I am using Ram and Wire EDM - However they are a sort of
mixture of commercial and homebuilt - What I did was find some distressed
commercial units and rigged them up with a combination of software and
hardware - I've been working on a homebuilt Wire EDM for quite a while but
it seems that there is never enough time to devote to it - Now that the
newer Wire EDM equipment is out it is sometimes possible to find some REALLY
GOOD DEALS on the outdated stuff - The problem is just like that with buying
outdated CNC Mills - The controllers are horrible to keep running - A
combination of some of the homebuilt EDM power supplies that have been
published recently along with homebuilt CNC controllers could put these old
EDM machines in the home shops in the near future -

5) Re: Laser cutter - Several years ago I designed a laser welding machine
as a consulting job - The company used a YAG laser - I'm not a laser expert
but have spent qute a bit of time around industrial CO2 lasers also - If
possible I would suggest going with CO2 because it is a LOT safer and easier
to provide protection against damage to the operators -

6) Re: Tool Changes and Tool Length Offsets - Several people have responded
to this query but a side comment may be of interest - One key to a good
workable multiple tool system is an easy and reliable way to remove and
reinstall tools so that they are always the same length relative to some
reference dimension - I use ERICKSON quick change tools and have also used
several other systems - The problem with them is they are horribly expensive
for the hobbyist - I've been working on a homebuilt quick change tooling
system and while it isn't as nice as the commercial ones it is more than
adequate for home shop use and can be easily built - Everything is still in
the sketch stage but the actual tooling has been built and tested - This
will be a HOME SHOP MACHINIST column in the near future - I'll see if they
have any objections to my posting it to this list before it is published in
the magazine -

7): Re: STEPSTER software - I have downloaded this software and taken a look
at it - Haven't had time to actually get it running - I was saddened to hear
that the author had died recently - My question is this - Who is
successfully running this software and has anybody made any improvements to
it - Does anyone know of other CNC software available in source code - Or
have any of you written your own - I don't want to reinvent the wheel if
it's not necessary -

Roland Friestad <cardinal.eng@...