11-25-2006, 12:54 PM
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 | | | Join Date: Feb 2006 Location: USA
Posts: 926
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Originally Posted by ProtoTrains  I'd also be interested in a high-speed primary spindle |
It seems there won't be one. Here's a post that Greg made a few days ago on the Yahoo list: The air driven spindle we offer is made by Air Turbine Tools
http://www.airturbinetools.com As I understand it, these are the same guys that
make the high speed spindle in the Haas Office Mill. They make a model with
steel bearings, but it's really no better than our inexpensive Proxxon
companion spindle. The models we offer have ceramic bearings and are quite
different, with 0.0002" TIR or better. We can deliver any of the Air Turbine
Tools products, but we list the 602JS model because so many people have been
asking about circuit board prototyping and other things that require tiny
cutters and high speed. They also make larger models, but be prepared to
supply a lot of air if you want any significant horsepower out of an air
spindle. I have PDF files if anybody wants detailed information.
If you want one of the small Air Turbine spindles, I would suggest ordering
after December 15. They are switching the collet style and moving toward an
ER style which is much more of an international standard. I forget if it's
ER10 or ER12, but the ER series are rapidly replacing the less common
geometry.
We continue to be impressed with the value of the Proxxon, our low cost cost
high speed spindle. With steel bearings and 0.001" TIR, it's a long way
from a true precision high speed spindle like the Air Turbine model, but
it's vastly superior to a Dremel. We have pushed it pretty hard and it
never seems to give up. Works great for engraving.
Some people have removed the spindle cartridge in the PCNC and replaced it
with a high speed induction spindle. These commonly go to 10K, 20K, or even
45K RPM. We designed with an 80 mm cartridge diameter, which is a common
spindle size, in order to allow modifications like that. The higher speed
and horsepower models often require water cooling. This would also require
replacing the stock VFD and replacing it with one that can go to 400 hz. At
4500 RPM the stock VFD is putting out about 125 hz. We have looked into
this as an option, but it would just about double the price of the machine
and you lose all low speed action. If you run dry, you can do it for about
$3000 using the sorts of spindles that are designed for woodworking routers.
A metal working high-speed spindle is more. Since that would not appeal to
most customers, we probably will not be offering it as a Tormach option. It
will remain as an individual customization done by an owner at their own
risk.
One interesting option is the old Bridgeport Quillmaster (Google images
"quillmaster"). It will provide a 1.5x speed up and also has the capability
of reaching into tight corners. Because we designed to industry standards,
the Quillmaster fits on the PCNC 1100 just fine and some people are mounting
them on their machines. You can find those on Ebay sometimes.
We continue to look for alternatives. We have several designs in-house, but
none have even gotten to the prototype stage yet. We are also looking for
existing cost effective commercial options, like the Air Turbine, that we
can offer. As always, we are open to suggestions.
Greg Jackson
Tormach LLC |
If the spindle bearings were up to it, it would be tempting to fit a jackshaft to the side of the head. Two stages of 1.58:1 increase (motor pullley to jackshaft, jackshaft to spindle pulley) would give 10krpm at the spindle, retaining the benefits of the TTS.
Randy  |
Linear Mode
