Milling acrylic
 

Every now and then I have to mill air channels into 1/4 acrylic sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots 1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes on
the table.

I would appreciate help in this matter

Uwe

"Jaggy Taggy" wrote in message
...
Every now and then I have to mill air channels into 1/4 acrylic sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots 1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes
on
the table.

I would appreciate help in this matter

Uwe


Several options come to mind -- if it is a straight slot, you can use
a table saw with a dado blade in it. I have used a router with
acrylic before, but the solution is somewhat counter-intuitive --
you have to go FAST not slow. Use a sharp cutter and feed it
fast -- if you go fast, the chips carry the heat away - if you go slow,
you get "melted pizza cheese"

mikey

"Jaggy Taggy" wrote in message
...

Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes
on
the table.

Tried double stick tape ?

--

SVL

Jaggy Taggy wrote:
Every now and then I have to mill air channels into 1/4 acrylic sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots 1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes on
the table.

I would appreciate help in this matter

Uwe


For holddown a vacuum table would be ideal, with a raised frame around
the perimeter of your application..
Easy to make one custom for your application.

--
- -
Rex Burkheimer
WM Automotive
Fort Worth TX

On 3/17/05 9:49 AM, in article , "Rex B"
wrote:

Jaggy Taggy wrote:
Every now and then I have to mill air channels into 1/4 acrylic sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots 1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes on
the table.

I would appreciate help in this matter

Uwe


For holddown a vacuum table would be ideal, with a raised frame around
the perimeter of your application..
Easy to make one custom for your application.

Yes, that would probably be the best. I even have a vacuum pump somewhere.
But how do you make the table, did you built one yourself??

uwe

Jaggy Taggy wrote:
On 3/17/05 9:49 AM, in article , "Rex B"
wrote:


Jaggy Taggy wrote:

Every now and then I have to mill air channels into 1/4 acrylic sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots 1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such shapes on
the table.

I would appreciate help in this matter

Uwe


For holddown a vacuum table would be ideal, with a raised frame around
the perimeter of your application..
Easy to make one custom for your application.


Yes, that would probably be the best. I even have a vacuum pump somewhere.
But how do you make the table, did you built one yourself??

uwe

I haven't built one, but it's a relatively simple project from what I've
read in the RCM archives. Basically a piece of plastic with holes
drilled in it, over a cavity that can be hooked to vacuum. Your holes
have to be very small of course. Picture a small air-hockey table
running with reversed polarity :)
I'm sure others more knowledgable will chime in. If not, Google
"vacuum chuck".

--
- -
Rex Burkheimer
WM Automotive
Fort Worth TX

Jaggy Taggy wrote:
Every now and then I have to mill air channels into 1/4 acrylic
sheets,
which afterwards are being glued up for air manifolds.
The pieces are strips of 2" X 18" and I need to make 17" long slots
1/4"
wide all the way thru as well as 3/4 depressions about .050" deep.

Once I did this on a router but it is too fast and gums up the
material.
Now I try a milling machine, but I am still wondering about the right
speed/feed as well of course about a clever way to hold down such
shapes on
the table.

I would appreciate help in this matter

Uwe

Its ALL about the tooling with Acrylic and many other plastics.
Have a look around at this site: http://www.antaresinc.net/

There is a link that shows industrial tooling, and then sharpened
tools. You will have excellent success with their Parallel single flute
"D" blank cutters.

They have some really good information in their "fact Sheets" link.

Others sell "D" blank tooling, but that is the only quick site I could
connect you with.

(crown cutters is another)

Chris L