Cutting on acrylic instead of polycarbonate...

Post: # 11491Unread post **aaron** Sun Nov 21, 2010 1:36 am

Well, I got some black .062" thick delrin sheets, hacked them into an approx 12" circle. I did a couple small tests with them with a brand new sapphire... seems promising. However, they are warped real bad so I didn't cut much ... and they didn't come with any protective masking so they have scratches on 'em.

I'm going to get a couple pieces of glass tomorrow and try and sandwich a piece in there and put it in the oven real low (old trick to flatten warped records) and then try again.

Since I couldn't get a consistent groove depth, the chip was pretty fluffy and shaved-looking... but I did get a couple real nice lines that wrapped around the spindle. Sound quality seemed close to acrylic (maybe a little less noise).

I'd also like to get some vaccuum action going and try and heat the stylus sometime.

Post: # 11495Unread post **cymbalism** Sun Nov 21, 2010 9:14 am

When I tried it, I got the same fluffy shavings only on the colored acrylic but you couldn't listen to it, it was just shunning with the music hidden in there somewhere. The chip should be fine and hairlike just like the chip from an acetate - at least the chip on the clear comes out like that for me.

Post: # 11509Unread post **fraggle** Mon Nov 22, 2010 3:22 am

has anyone tried HIPS sheet? i can get this here in black....

Post: # 11558Unread post **aaron** Wed Nov 24, 2010 11:46 am

I haven't tried HIPS..

I don't know about delrin/acetal... I tried to flatten it with a couple pieces of glass and it ended up breaking the glass as it was cooling. Anyone have any ideas on flattening this stuff? The melting point is pretty high... i think like 340-361F.

I've found a source for EXTRUDED black acrylic... cymbalism, do you think that would work as well as clear? I know you mentioned you've tried the casted colored stuff, but I wonder if this would be better.

I did a test (with clear acrylic) last night with a new stylus and it's even better than my last sample. VERY quiet.

Post: # 11561Unread post **fraggle** Thu Nov 25, 2010 1:04 am

@ Aron can you say something about the background noise compare to polycarbonate? cheers

Post: # 11562Unread post **cymbalism** Thu Nov 25, 2010 9:16 am

aaron wrote:I haven't tried HIPS..

I don't know about delrin/acetal... I tried to flatten it with a couple pieces of glass and it ended up breaking the glass as it was cooling. Anyone have any ideas on flattening this stuff? The melting point is pretty high... i think like 340-361F.

I've found a source for EXTRUDED black acrylic... cymbalism, do you think that would work as well as clear? I know you mentioned you've tried the casted colored stuff, but I wonder if this would be better.

I did a test (with clear acrylic) last night with a new stylus and it's even better than my last sample. VERY quiet.

As far as I know if it's extruded it should work. I would say get a piece and test it. My support can get almost anything but extruded colored acrylic is not easy to come by they said.

Let me know the results man!

@fraggle

The background noise is pretty quiet man, you'll have to try it out - you'll be very surprised

Post: # 11564Unread post **aaron** Thu Nov 25, 2010 11:47 am

I've never had a successful cut with polycarbonate and sapphire, and I've never cut it with a diamond, so I can't really speak to that.

The latest acrylic cut seemed pretty damn quiet though... as long as you keep the swarf away from the needle and don't cut too deep. It seems like you reach a threshold with the groove depth where it will start squealing.

As far as extruded black acrylic sheet, Grainger sells it (http://www.grainger.com/Grainger/Sheet-Stock-1UNZ5?Pid=search) and also interstate plastics (http://www.interstateplastics.com/Black-2025-Acrylic-Extr-Paper-Sheet-ACRB5EP.php). The thinnest I've found is .118", but I think that would be OK.. kinda close to a 180 gram pressing maybe?

I'm going to try and get some from Grainger on Friday (if they have it in stock) and see what happens. Sure beats spending $350 on a diamond.

Post: # 11565Unread post **fraggle** Fri Nov 26, 2010 3:45 am

ok i tried hips which doesn't sound good. lot's of fluffy stuff and shit loads of background noise. abs seems to be alright though

Post: # 11566Unread post **fraggle** Fri Nov 26, 2010 4:21 am

@ aaron thats 3mm thick. i think a 180gramm is about 2mm which is already bloody thick....

Post: # 11567Unread post **fraggle** Fri Nov 26, 2010 4:51 am

I found black acrylic in 2mm thickness.

http://kuslicht.de/webshop/product_info.php?info=p128_Acryl-XT--black--2-mm-thick.html&XTCsid=3af74fc4e90cd60614dc9e32f845f4a1

not very cheap though...

Post: # 11569Unread post **cymbalism** Fri Nov 26, 2010 9:23 am

I'm telling you guys, colors will not cut. I've tried it - just not happening the way it does with clear

Post: # 11570Unread post **aaron** Fri Nov 26, 2010 10:03 am

But you're talking NON-extruded plastics, right?

It seems like black extruded acrylic that's less than 1/8" thick is pretty hard to come by

Post: # 11573Unread post **cymbalism** Fri Nov 26, 2010 12:03 pm

aaron wrote:But you're talking NON-extruded plastics, right?

It seems like black extruded acrylic that's less than 1/8" thick is pretty hard to come by

It is, I've spent a lot of time researching it with my supplier

Post: # 11578Unread post **aaron** Fri Nov 26, 2010 1:16 pm

So I guess it comes down to this for acrylic:

-Use clear 1/16" extruded
-Use black 1/8" extruded

It's really too bad they don't make clear extruded in 1/32" width... then you could just sandwich a couple together and make the insides of them black.

Post: # 11619Unread post **Jccc** Mon Nov 29, 2010 4:58 pm

i just picked up some acrylic and was wondering what everyone uses to cut it into pieces?

i tried cutting it and it just started to break up kinda like glass.

On a side note with a piece that was decent to cut. I got some good sound out of it. There was a little surface noise but when the music came in it sorta was hidden in the background
With nice swarf going straight to the center.

Post: # 11620Unread post d Mon Nov 29, 2010 5:07 pm

I see that quite nice result you guys getting. I just got stylus and will try cutting this week.
Got some work years ago with acrylic, and it likes to brake like glass, so best I think is to go to CNC shop for sheets cut to disk.

Post: # 12389Unread post **carter** Thu Jan 27, 2011 2:05 pm

I inquired with this place in SD about acetal and the response seemed to indicate they couldn't cut it round to record size/thickness without some warping.

Can anyone confirm this?

Post: # 12392Unread post **opcode66** Thu Jan 27, 2011 2:18 pm

Generally a CNC Machine is used to cut the circles. I think the center holes are punched our or cnc'd.

Post: # 12393Unread post **carter** Thu Jan 27, 2011 2:19 pm

They indicated they could not create 'blanks' without the result being warped. Do you think it can be cut round/flat with 1/16th thickness without warping?

Post: # 12423Unread post **aaron** Fri Jan 28, 2011 6:06 pm

This sounds like the same problem I had trying to cut Delrin... it cut real nice with a sapphire, but I made a round blank out of a 12x12 sheet of it, 1/16" thick. It was warped all to hell... and it didn't come with any protective sheeting on it, so it had scratches here and there. I got 3 seperate pieces and couldn't really use 'em.