Polymer Concrete

[ericdwilso]

I am looking to build a CNC machine from polymer concrete & I have a couple of questions...
1. Can anyone point me in the direction of a suitable supplier for the epoxy? or Epoxy & filler?
2. Does anyone know how sensitive the granite or quartz / epoxy mixture would be to moisture content? Stated another way, how important is it to dry the quartz or granite prior to mixing?
Thanks, Eric

[NC Cams]

Lots of relevant discussion re: use of concrete to build and/or stiffen machine tools here:

http://www.cnczone.com/forums/showthread.php?t=25283

[pminmo]

What specifically is polymer concrete? Does it use portland cement?

[Geof]

Originally Posted by pminmo What specifically is polymer concrete? Does it use portland cement?

This came up in a Google search. After reading it I have come to the conclusion that polymer concrete is a misnomer; it seems to be more a case of aggregate reinforced plastic.

http://irc.nrc-cnrc.gc.ca/pubs/cbd/cbd242_e.html

[ericdwilso]

Originally Posted by NC Cams Lots of relevant discussion re: use of concrete to build and/or stiffen machine tools here: http://www.cnczone.com/forums/showthread.php?t=25283

NC Cams... I read that thread already... None of the manufacturers that I saw offer the raw material only. If someone knows different, I would be interested in hearing. Eric

[ericdwilso]

Originally Posted by Geof This came up in a Google search. After reading it I have come to the conclusion that polymer concrete is a misnomer; it seems to be more a case of aggregate reinforced plastic. http://irc.nrc-cnrc.gc.ca/pubs/cbd/cbd242_e.html

Polymer is just that; concrete that is made of epoxy resin mixed with a filler, generally crushed granite or quartz. Usually the filler has different aggregate sizes to fill the the voids so that epoxy usage is minimized (also increases strength I believe as the effective "thickness" of the epoxy is reduced). Apologies if the terminology is off. Eric

[txcowdog]

The government used epoxy reinforced concrete to make missile silos back in the '60's that achieved a strength of 200 psi. Quite impressive for concrete but beyond that little tidbet I know nothing about the stuff.

[lgalla]

EH!Eric,
What is the use?Filling a base or actual parts of a machine?Google search [epoxy granite]will find lots of info on uses in machine building.Polymer concrete is usually polyester resin and stone and not suitable for machine use . Epoxy granite is used in machine tools as it has 10 times the damping of cast iron and 50 times the damping of steel.Usually bags of fillers are dry.
For good pricing on epoxy try www.shopmaninc.com
If you look for granite you may find "densified granite"This is not granite but coloured chips of polyester for countertops. not suitable!!!
I was about to "ASK THE EXPERTS"about epoxy granite and found your thread.
Hope they have some answers.I want to use epoxy granite as a cnc router poured table top for a level surface and damping.A final pour of unfilled epoxy can acheive a level surface to .005.Search the zone for epoxy surface plate.
Hope this helps.I have used epoxy granite but not for machine use so I am no expert on the subject.Hope someone else can enlighten us.
Larry

[pminmo]

So sounds like polymer concrete doesn't use portland. I wonder if concrete countertops are really polymer concrete?

[Udayan]

Hi !! I would like to know the percentage / proportion and size of agrregate for preparing Grout for filling in Fabricated Base of a CNC Lathe we propose to build in an Enginerring College as a project to be undertaken in Mechanical Engg Department in India -- I have been invited to offer services as a Guide to build a CNC Lathe. Since only one machine has to be bulit for the department producing a Pattern and C I Casting would be time consuming and cost prohibitive as such Fabricated Bed is proposed to be used which is proposed to be filled with Epoxy Grout . Which is type of Resin & Hardner most popular ?

I suppose there are several experts on this Forum who would offer information

Udayan

[rowbare]

Tons of information in this thread:
http://www.cnczone.com/forums/showthread.php?t=30155

Here is an index to relevant portions:
http://www.cnczone.com/forums/showthread.php?t=38800

And a practical application filling a base with epoxy granite:
http://www.cnccookbook.com/CCMillEpoxyFill.htm