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Todd Schwartz
10-31-2007, 9:49 AM
Any difference in vector cutting extruded acrylic vs cast? I have used cast up to this point with good results, but the local plastics supplier only has extruded on hand. I will not be rastering anything so do not need the frosted look that cast gives when rastered. Plus I found out that extruded is less expensive. Working with 1/8" material.

Thanks,

Todd

Scott Shepherd
10-31-2007, 9:52 AM
Not really, no. Should be about the same on something that thin. I've had a little bit of difference in the thick stuff, but not the thin. That's just my personal experience with it.

Joe Pelonio
10-31-2007, 9:55 AM
For cutting the difference is very little, but extruded does come out a bit smoother.

For engraving cast is the only way to go. It gives that frosted look, and remains fairly clear when paint filling. Extruded gives more of a textured muddy look to the engraving.

Frank Corker
10-31-2007, 10:26 AM
Another point worth mentioning is that extruded stinks when it's cut but cast has an almost sweet smell

Rodne Gold
10-31-2007, 10:38 AM
Lasers cut Extruded better , but extruded is VERY prone to stress cracking after being laser processed. This happens when some solvents and other chemicals are used or near it. This happens anytime , sometimes immediately , but mostly a little time down the line.
So depending on what the part is for , I would be a little careful. Especially if its a repeat order and you used cast before.

Larry Bratton
11-01-2007, 9:10 PM
Any difference in vector cutting extruded acrylic vs cast? I have used cast up to this point with good results, but the local plastics supplier only has extruded on hand. I will not be rastering anything so do not need the frosted look that cast gives when rastered. Plus I found out that extruded is less expensive. Working with 1/8" material.

Thanks,

Todd
Todd:
Rodne is right there. I believe what he is speaking of is called "crazing". I've cut a good bit of acrylic lately, both cast and extruded. For whatever reason I've experienced the problem with extruded and not cast. BUT..for the difference in the price, if you waste some extruded your not killed. Just don't clean it with any kind of chemical stuff before vectoring and it should serve you well.

William Johanson
11-12-2007, 11:10 PM
I have been working on some acrylic projects lately and I am doing only cutting. I do need to do some bonding though and any thing I have tried is cracking the edges. I tried the Weld-on and several other solvent type bonders, Cracks every time. I have also used superglue but it "hazes" too much. I have had some success with a plastic glue but it takes forever to dry and can be very messy if you are not very careful. Any Ideas?

Rodne Gold
11-13-2007, 12:52 AM
There is a way of stopping the cracking , and that is to anneal the pex. Leave the cut parts in an oven at about 80c for 1 hr per mm thickness and let them air cool , this stress releives them.
Alternatively , use only cast acrylic with tensol glues. If you use extruded , use glues specific to extruded (Degussa makes many)
One can debur and scrape edges too , which does somewhat releive the problem.
How to tell whether its extruded or cast:
Burn a piece , extruded burns silently and will drip molten balls , cast burns with a crackly/smokey flame and wont drip.

Larry Bratton
11-13-2007, 7:34 PM
I have been working on some acrylic projects lately and I am doing only cutting. I do need to do some bonding though and any thing I have tried is cracking the edges. I tried the Weld-on and several other solvent type bonders, Cracks every time. I have also used superglue but it "hazes" too much. I have had some success with a plastic glue but it takes forever to dry and can be very messy if you are not very careful. Any Ideas?
William:
Did you use Weldon #3? If not, which one?

William Johanson
11-13-2007, 8:13 PM
No it is Weldon #4. Does that make a difference? Thanks