clear PVC order - Page 2

titus · #11 03-07-2002, 05:17 PM

Hello,

I believe I can step in here as I have enough experience with both extruded and cast material.

The extruded was made by pushing the resin out as it cools, while the cast (I hate it when they call it cell cast, make it sounds fancy and no body call them this in the acrylic industry) are made entirely in the mold.

Bottom line, if you are making products commercially and plan to ship them out via UPS, you want something that is inherently strong. Extruded just breaks too easily during shipment and such. Not worthwhile.

Aquattro · #12 03-07-2002, 08:36 PM

Titus, are you saying the actual plastic broke, or the joints came apart? I find it difficult to imagine either breaking unless the UPS truck drove over them. How long did you let the joints cure before shipping?
If someone is going to make their own and not ship it to themselves, I see no point in spending the money on cast when extruded is so inexpensive.

DJ88 · #13 03-07-2002, 08:41 PM

Brad,

Extruded will snap like a dry twig. take my word for it. lol. I have broken tubing like it was a piece of glass. :eek: it doesn't take much.

Why do you think skimmers n reactors cost so much to buy? Cell cast isn't cheap. It has to take a lot of abuse.

Aquattro · #14 03-07-2002, 09:12 PM

Darren, I've dropped pieces of tubing without damaging it. I guess I need to drop it better :D
Until I find a reasonable price on cast tubing, I'll just make sure I don't break anything!! [img]tongue.gif[/img]

stephane · #15 03-09-2002, 01:28 PM

I made this skimmer whith extruded cast and it work just great and save a lot of $$$$$$$$ and like reef raf said i dont see how you could break it until if you drop it by the window I work whith acrylique for long time and the only difference i see between them is the tickness extruded are often less tick than cell but other than thay are made of the same material just made differently

you not suppose to play football whith reactor and
skimmer just take a litle more extra care and all will be find your just not suppose to drop it and why you do. you handle a lot of ting in you life that are not bullet proof and have no problem. Did
company make toaster or blender or radio drop proof just in case you drop it?

LFS could ship metal halide bulb whitout any problem so i dont see why a skimmer or a reactor well made could not be ship

[ 09 March 2002, 09:44: Message edited by: stephane ]

Bryan · #16 03-09-2002, 02:23 PM

Stephane:

Nice looking DIY skimmer. If you don't mind, what is the o.d and the height of the main riser.

Quote:

Originally posted by stephane:
I made this skimmer whith extruded cast and it work just great and save a lot of $$$$$$$$ and like reef raf said i dont see how you could break it until if you drop it by the window

StirCrazy · #17 03-09-2002, 02:34 PM

Titus, "Cell cast" is used in the industry as you have to be able to tell the difference between that and "Continuous cast" we used continuous cast in the skylight factory whare I worked befor I got into the Navy, as for how strong, well it like anything else depends on the manufacturing and quality control. Extruded Acrylic is the most consistant when it comes to thickness but it optical quality isn't as good as the other types. this is the MAIN difference.. Cell cast is the highest optical quality, Continuous cast is next and then finaly Extruded.

now having said that Extruded ends up being softer than cast methods so it will scratch easyer and has a tendency to gum up tools more, also because of the softness it can adsorb solvents faster than cast which can result in incomplete or brittle seams. to corect this just use a solvent that sets up a little slower.

hope this helps

Steve

DJ88 · #18 03-09-2002, 03:17 PM

Stephane,

I will speak from experience with extruded acrylic.

It is brittle in comparison to cell cast. I have dropped pieces of tubing by accident and it cracked or shattered. Very eaisly. It will crack and shatter the same way if you aren't careful when you are drilling or cutting.

After making skimmers and a few other gadjets with extruded I would not ship it anywhere as it woudl not make it at all.

titus · #19 03-09-2002, 05:36 PM

Hello,

I have made quite a few items back when Canreef was in full swing. And I can tell you the following are facts:

1) Extruded gums up, melts easier, but is more brittle.

2) Cast gives you clean cut, takes longer to melt, but is optically clear and doesn't break easily.

3) I wish I can take a picture of the broken reactors and skimmers but I threw them all out. Some of the reactors just break as if UPS had step on it. Don't ask me why. I'm just speaking what's happened. Send a message to Premium Aquatics and ask Jason about it. He can tell you what I'm telling you here.

4) As of 1) - 3), I do not buy or make things out of extruded tubings anymore. Period. I don't care what. If this mean the end product is more expensive, so be it but it's a better built unit and it's worth both mine and the customer's time.

5) The reason I recommend cast for even the DIYs is because 2) and I don't want to sell cheap material. Think about it, I have some leftover extruded material sitting around but you don't really see me really trying to get rid of them. I'd rather not recover the cost of paying for those material than selling something cheap.