So whats the Exopy Granite Mix?

[antsals]

Been reading the extremly long thread on the forum that seems to have been going a long while!!!

In simple I looking at making a cnc milling machine bed out of the epoxy granite. What is the "best" mix and where do I get the supplies from? I'm based in the UK so suppliers in the UK maybe easier?

What ratios should I be using and do I need to vibrate the mould / pour?

Thanks
Ant

[ckelloug]

Ant,

There's still a lot of discussion about what "right" is. I 'll post my current mixture design with the agsco reference material and the zeeospheres but properly dispersing zeeospheres so that they help rather than hinder is currently a topic of discussion. In general it is my opinion that without some serious additives that using particles this small will be difficult.

The model's result based on my current assumptions and estimated packing density for zeeopeheres is the following. The measured values for zeeospheres are much lower and using them in the model produces designs that aren't going to work. My estimated values are closer to how the system should behave if we can find additives and processes to take care of the issues.

For what it's worth,

My current reference formula suggests the following:

0.329221 Agsco #6 Al2O3
0.180515 Agsco #4 Quartz
0.139481 Agsco #2 Quartz
0.144192 Agsco #2-0 Quartz
0.108832 G800 Zeeospheres
0.097759 G200 Zeeospheres

Predicted density 88%.

The numbers are by volume of solids so take the volume of material you want to make and multiply by the number given. Then take that and divide by the specific gravity of the material to get the weight of that component.

One again, this is where we are on the thread but there are a lot of concerns right now about whether it will work as well as the model says it will. I don't have data on performance for this mixture at present.

Regards.
Cameron

[MillworkMike]

Im just curious...... Did this idea start/come from the CNCBridges guy or is this something completely different??

[ckelloug]

I don't really know. I got involved because I woke up one morning, decided it was what I wanted to do, googled and found a bunch of others interested too.

I think the CNC Bridges guy may have been the cause of the beginning of the discussion. Having spoken with the CNC Bridges guy however, I am absolutely certain that the problem of designing the material right is a lot more complicated than he thought it was.

[MillworkMike]

WOW.... I just realized who the CNCBridges guy is a couple days ago!! I use to work for him abt 12 years ago while I was in High school.. All I can say is WOW!!