You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
extrude vs cast
- Thread starter Rob Top
- Start date
For skimmer, it usually make no difference, but there is some minor workability difference when you solvent weld the acrylics, I heard. I don't notice much, if any difference in term of workability.
Extrude is softer, less expensive, easier to cut. Cast is harder (due to higher molecular weight of the polymer), more expensive, cut/scratch/bend less easily. I will go with cast if you want something that last.
Extrude is softer, less expensive, easier to cut. Cast is harder (due to higher molecular weight of the polymer), more expensive, cut/scratch/bend less easily. I will go with cast if you want something that last.
What about clear PVC? Searching and searching the web it is easier to come by and cheaper too. I am not looking to cheap out on this, HOWEVER the less I spend on the, the more I can spend on... And really the only reason to use a clear material is to beable to view water leavels and ease asjustments. If I go with clear pvc, I can get all my materials from 1 supplier and save on shipping.
I have to disagree - cast acrylic is esential! Believe it or not, acrylic absorbs water - cast acrylic is more molecularly dense and therefore absorbs less than extruded. The problem with extruded material and why it's not good for water applications is the face that over time it will absorb enough water, which in turn will make the material expand which will lead to....you guessd it - joint failure.
PrecisionClarity said:I have to disagree - cast acrylic is esential! Believe it or not, acrylic absorbs water - cast acrylic is more molecularly dense and therefore absorbs less than extruded. The problem with extruded material and why it's not good for water applications is the face that over time it will absorb enough water, which in turn will make the material expand which will lead to....you guessd it - joint failure.
I work at a plastics plant and we fuse extruded acrylic the extruded ABS for a outfit that forms them into high end hot tubs. HUMMM
PrecisionClarity has a point I have seen. Extruded acrylic does absorb some water when there is a temperature difference between the inside and outside. On my 29FW I made a lid out of extruded acrylic. As the water condensed on the acrylic, it caused the acrylic to warp and bow upwards. In the last year, it has bowed almost 3/8" . Thats my expirience with flat stock. With tube, I dont think this is an issue, as the tube itself will not allow distortion. What it will do is cause internal stresses in the acrylic, and if you get a chip or deep scratch, it may use that as a fracture point and break out over time.
JMO.
JMO.
Sponsor Reefs
We're a FREE website, and we exist because of hobbyists like YOU who help us run this community.
Click here to sponsor $10:
