Re: Machining acrylic
- I have little experience buying tools online, but most of the other
companies I buy from do indicate stock before you attempt to buy
LMS does, and I appreciate it. McMaster doesn't per se, but I have
ordered hundreds of things from them and have never had to wait more
than few days before they shipped.
Virtually all of the electronics suppliers do as well. This includes
DigiKey, Allied, Radio Shack and others.
So in my case, it seems odd.
The point is moot in any case as one can always call them on the
phone, where I am sure they will let you know. I think I will try
that route with Grizzly next time.
--- In GrizHFMinimill@y..., "jjfear" <jjfear@i...> wrote:
> I don't know of any company that does this. Every time I have
> anything from Grizzly or several other premium companise. I have
> notified by email immediatly that the item is not in stick. My
> is that opening their inventory to access on the net would be
> expensive, and probably dangerous from a security standpoint. I
> wouldn't want my competetors to know what I had or didn't have in
> stock. A simple bot could log that info.
> My main complaint is that they do not revise their closeout items on
> their web site when they've, in fact, been sold out. Otherwise, it
> seems normal.
- I very recently joined the minimill group and have just completed
going through the 432 messages that have been posted.
One point appeared in several postings concerning the machining of
acrylic materials. This was the possible use of a device called a
cold gun for cooling the material.
Unless one has a huge supply of air available to operate the cooling
gun, it is probably not a practical device. Two of the companies
that market similar devices are EXAIR and VORTEC, whose web pages are:
For a very small unit the air requirements are 8 SCFM at 100 psig.
Somewhat larger units require 15 SCFM at 100 psig. To deliver these
quantities of air compressors of 5 to 10 HP would probably be
required. This suggests that these devices would most probably be
useful in a large shop environment, which has surplus quantities of
For information, I do have a griz minimill, a 7x10 HF minilathe, and
a Taig lathe. I have been a member of the Minilathe group since mid
1999. I am considering buying an additional lathe, a 7x12 from
Homier. One of the wise members of the Minilathe discussion group
(not me) says that one can not have enough lathes.
- You mean we don't all have a 200 gallon 5 HP
--- nplaks <nplaks@...> wrote:
> I very recently joined the minimill group and havehttp://www.exair.com/spotcooling_products/cg_page.htm
> just completed
> going through the 432 messages that have been
> One point appeared in several postings concerning
> the machining of
> acrylic materials. This was the possible use of a
> device called a
> cold gun for cooling the material.
> Unless one has a huge supply of air available to
> operate the cooling
> gun, it is probably not a practical device. Two of
> the companies
> that market similar devices are EXAIR and VORTEC,
> whose web pages are:
> For a very small unit the air requirements are 8
> SCFM at 100 psig.
> Somewhat larger units require 15 SCFM at 100 psig.
> To deliver these
> quantities of air compressors of 5 to 10 HP would
> probably be
> required. This suggests that these devices would
> most probably be
> useful in a large shop environment, which has
> surplus quantities of
> air available.
> For information, I do have a griz minimill, a 7x10
> HF minilathe, and
> a Taig lathe. I have been a member of the Minilathe
> group since mid
> 1999. I am considering buying an additional lathe,
> a 7x12 from
> Homier. One of the wise members of the Minilathe
> discussion group
> (not me) says that one can not have enough lathes.
> Norman Plaks
> Raleigh, NC
> To unsubscribe from this group, send an email to:
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- Update on acrylic:
The task I have in mind is to bore round pockets into 1+" cast
acrylic, and have a clean enough finish that I can wet sand the
result into being nearly perfectly clear.
So now that I have a mill, I tried the most blunt thing I could think
of - I mounted up a 1" end mill, brand new and very sharp (cut my
hand just mounting the thing in the holder).
I ran the mill at low speed with the shifter on low/high torque and
fed the mill in very slowly.
It made very long trails of swarf. The mill did not budge, though I
was startled at some of the sounds the cutter made. ;)
The resulting pocket seems to be perfectly round, and has a better
finish than I had figured for. Neither the swarf or the material got
warm, let alone hot enough to melt it.
Next I will try using the boring bar to make an even cleaner finish
on the sides. If anyone knows of a tool one could use to finish up
the bottom of the pocket on a mill (yeah I know, get a lathe) I would
appreciate knowing about it.
- Hrmph, so I tried a boring bar and the result is a quite different
finish. That is, not nearly as nice as the end mill made. Is this
feed & speed thing? Or how shart the boring bar is(n't)?
Sorry if I am boring (heh) you with all my questions. :)
> The task I have in mind is to bore round pockets into 1+" cast<snip>
> acrylic, and have a clean enough finish that I can wet sand the
> result into being nearly perfectly clear.
- Bill has photos of his in a folder on the Photos section of this
I think what they are is a Taiwanese made version of the older Atlas
CH-10 mini mill, the precurser to the ones sold by Grizzly, Harbor
Freight, etc. Here is a guy that has the Atlas:
It looks a lot like mine.
REX, then takes those and reworks them to be more true, stiffens up
the column and replaces the Z rack and pinion drive with a lead screw
and handle. He also makes all of the lead screws 10 dpi.
The differences between the basic CH-10 and the newer Grizzly et. al.
mill are the CH-10 has a belt drive, slightly different spindle
design, different electronics (no need to be at low speed to start
the spindle). The basic CH-10 also does not have the fine feed found
on the new ones.
Other differences are the column and head are aluminum while I
believe the Grizzly is pretty much all iron. Seems REX does other
custom modifications such as those to Bill's mill. I think I recall
Bill saying his column is iron, and his spindle is R8 vs. MT3.
> I have not seen this Rex mill everyone is talking about. Anyphoto's out
> Jordan in NYC