PDA

View Full Version : Milling Azek & plastic component - feed speed & time estimates



johnm
07-12-2005, 05:04 PM
Folks -

Okay, next question... I need estimate cutting times and speeds for milling 1" Azek plastic trim material (I'll be using 4 x 4 sheets) into corbels and fence pickets.

I'll be doing 2D work, no surfacing, just cutting parts out. I've "nested" a sample of 40 corbel parts on a half sheet of Azek, and it shows an estimated time of about 1 1/2 hours.

I am fairly new to SB, have only used a benchtop for simple things in a school setting, but am planning on getting a 4x4 unit if a big job I am working on comes together. I need to get some realistic figures for production time so I can come up with a reasonably accurate estimate.

A 1" thick sheet of 4x8 Azek panel is about $220 and I can get 80 corbels per sheet, so my material cost is $2.75 per unit. I don't know about feed rates and how they differ for plastic to know if an hour and a half is a valid estimate.

When I plugged in my art, here's what I had for the milling parameters:

tool: 1/2 end mill, 15,000 RPM
Stepover .1750
Stepdown .5
Feed Rate 100 IPM

How does milling plastic for 2d applications work compare to milling wood? Also, do any of you have experience on how Azek or plastics are for Z carving - does the material cut cleanly or is it "fuzzy"? I would like to be able to to surface texturing if it'll work, and thought I'd ask first for pointers.

I'd appreciate any input you can offer!

John Moorhead
Lakeport, CA

srwtlc
07-12-2005, 08:28 PM
John,

I recently cut some victorian brackets from 1" Azek. It cuts very nice and easy. I can't remember what speed I ended up at, but I started at 0.5" deep/pass and 1.75"/sec and increased it on the fly until I thought it was fast enough taking into account the bracket design. Edges were clean with no fuzz.

The time required to cut out your 40 corbels will depend on the shape of the part, but I'm sure that you could cut at full depth and faster than I did with my PRT. I'd drop down to at least a 0.375" bit (0.5" is overkill) but I used a 0.25" one at 0.5" deep/pass at a final speed of at least 2"/sec .

Scott