Hi all,


It is the first time that I'm working with epoxy granite. Epoxy in my country is something very recent, about 5 years ago it was impossible to find an epoxy with affordable price for a hobby.


This magnificent project is inspiring me to build my own VMC:
https://www.cnczone.com/forums/verti...rum-posts.html

I've read a lot of topics and also other sites/articles about epoxy granite, trying to absorb the maximum knowledge for my project, after that I decided to buy 1.5kg of epoxy and aggregates to do some tests.

As recommended in this topic:
https://www.cnczone.com/forums/epoxy...tml#post315119

I'm using an epoxy with the following characteristics:

  • Low viscosity
  • Slow cure
  • Minimal amount of additives


For the mold I used plywood, in my country plywood is cheaper than MDF.

For aggregates I used:
  • Fine sand (dry), I believe that in English I can also call it play sand
  • Gravel washed, bought a bag from a store for aquariums


The release agent I used is the one recommended by the epoxy manufacturer, it is a wax, which must be applied to the wood with a brush.

----------------------------


Aggregates:






I mixed 50-50% of the two washed gravel


--------------------------

The process was done the same for the 3 tests.

I separated sand and gravel, mixed it in a bucket, mixed epoxy A and B in another bucket, and then put the epoxy in the bucket where it was sand and gravel.

These photos are from test 1 (12% epoxy):












Mold after (left) and before (right) wax applied:



------------------------------


I made the mold in fusion360 and the volume was 0.001822m³ , following these recommendations (found here on the forum):
"Measure volume of mold convert to mass using 2200kg/m3 epoxy granite"
I found the approximate mass of my test: 4kg

The tests were divided as follows:

Test 1
Epoxy 12%
Sand 30%
Gravel 58%


Test 2
Epoxy 10%
Sand 30%
Gravel 60%

Test 3
Epoxy 8%
Sand 30%
Gravel 62%


And the results were:


Picture taken right after filling the mold (epoxy granite still wet)








the release wax worked very well and it was very simple to disassemble the wooden mold: