Epoxy Granite Indicator Bases 

I know some people add fillers to resin and then mix in the hardener to get longer working time, but we always mix the resin and hardener thoroughly first an only then add the filler. It's easier to get a good mix that way and it doesn't take a long time to mix in the filler. As a bonus you can control the final consistency by adding filler little by little. Epoxy compatible pigments shouldn't affect curing time. I suspect that even pigments not marketed as epoxy compatible will mostly have no effect, but you mileage may vary :) Pumps are convenient, but to get small quantities correctly, mix by weight on a precise scale (like 1/100g resolution jeweler models that are super cheap on ebay). I can mix about 1g of stuff with good results on that setup. Some epoxies (usually 5 minute stuff, never West 105) tend to stay tacky and soft forever. Cheap stuff from no name sources works for me just fine but is usually a bit too thick for glass lamination (shouldn't be a problem for you). It can also be more allergenic, more smelly and maybe have a bit less strength but otherwise just as good as the expensive stuff. Just keep away from Chinese vendors :)

Nice project, especially the clear sample. For casting solid rocket propellant (solids + binder), they put it under vacuum to get rid of the voids, which allows them to minimize the binder. They also use a mix of large and small particle sizes, because the small ones can fit in the gaps between the large ones which increases the amount of solids that can be embedded.

Enjoyed, you want to minimize the distance from the magnet to the working surface for maximum holding power. ATB, Robin

Food for thought right there. A nice heavy base you could plop down on your bench and use with a machine is suddenly of interest to me.

One of those sanding machines (the cheap ones that just oscillate) make a very efficient shaker-plate. Cheap and cheerful too! Paddy

I have been looking forward to this video! For a couple of years now I want to try this epoxygranite but haven't actually taken the plunge yet. There are a lot of situations where it would come in handy (would love to use it as an overkill base for a 3D printer for example)

For better outside finish and also to avoid external bubbles before you add the epoxy, hardener and granite mixture to the mold, pour some epoxy and hardener mixture to the mold and impregnate the walls of the mold with a brush or a stick, then add the complete mixture. You will still have bubbles but at least not in the outside. The vibrator could help and also vacuum chamber could help too to extract the bubbles. Great videos thanks for sharing and bringing your experiences to us.

To figure out its damping property you can determine its modulus of elasticity using the mixture rule. E_Composite = E_filler*Volume fraction of filler +E_epoxy*Volume fraction of epoxy Its not super accurate rule for continuous fiber composites but for particle composites its ok. You could also look at the halpin-tsai method as well.

Also after cleaning with a solvent. Wash the part with an oxidation chemical like cloudy ammonia. This will remove all traces of oil.

For the healthiest epoxy, should I use gravel or sand and what size should I use it?

Can't believe I missed this upload. I did some research into epoxy granite a while ago. Seems like cool stuff, but definitely not the end all be all so to speak. Interested to see where you take this. Just as a tip, the surface voids can be filled with a coat of epoxy brushed on after removal from the mold.

I wonder if pressure(7-20 bar) casting or putting the complete mix under an extreme(

35 years of making GRANITAN the original epoxy granite made by studer and ciba if you want any help just ask if you put your mould on your washing machine while its on spin and vibrating it would reduce the holes in your casting and also reduce the amount of resin mix your using so its got a greater ratio of granite to resin

I would definitely mix the epoxy before adding the aggregate, and I'd also want to make sure the casting hasn't retained any of the abrasive properties of the garnet before I go sticking it on my machines

Quick question before I pull the plunge filling my mill base in with eg. with that 206 hardener....any idea how hot it got during curing? Clearly not enough to melt the plastic.

For easier to screw fasteners after degreasing, use dissimilar metals such as brass for the bolt. Stainless fasteners will cold weld when tightened without grease.

First I really enjoyed your video. Great to see new adventures. Might want to do something for your future degreasing efforts. Read the contents of a bottle of rubbing alcohol. There is oil in rubbing alcohol as well as water in the bottle you are using. Either pure Isopropyl alcohol or even Methyl Hydrate will work and not leave any oily residue. Let's say I learned the hard way about this in much more more cleanliness sensitive projects.

For a more stable mixture you should only use arround 10% epoxy by mass (with granit) and vibrate it after filling. For such small samples an orbital sander works fine. The surplus epoxy will set on top.

Going above and beyond the vibrating table, you can also cure them under vacuum to minimize air pockets and bubbles..

Hi, Any chance you're going to be at Van Mini Maker Faire? I'm going to be there with the BC society of Model Engineers and it would be great to see your stuff in the flesh. Great content, keep it up!

Grease/oily surface is preferred in that given situation, it would act like a mould release agent. There is wax/spray available for that purpose. Also I believe vacuuming works better at removing bubbles. Vacuum pumps can be made from refrigerator pumps.

We got some garnet that was apparently Indian in origin that was awfully contaminated with clay last month:/ A small subwoofer or Bluetooth speaker in a zip-loc bad that makes contact with the mold has helped me with even settling/compaction in castings. Cool project:)

All my life I’ve taken epoxy for granite.

Would it be possible to grind it flat and round with diamond wheel on a surface grinder?

I've been thinking about EG builds for along time... this is interesting. I've specifically been thinking of the easiest way to build a milling machine frame. What I've come up with is a weldment frame made of thin-ish (1/8 inch or so) steel filled with truss-like reinforcements which is then filled with EG. This would give the torsional and tensile strength of the steel with the intense compression strength and vibration dampening of the EG, and a lot of solid interfaces for the EG to act upon. THis way the machine frame itself is the mold, and you have an extremely rigid object that can be post-machined with, in theory, zero warp from stress relief in the material. In this way it may be possible for such a frame to inherit the flatness of whatever machine it is post-machined on, creating a very economically constructed frame that is much more rigid than its size would suggest. Of course this is all in theory within my head. Within the next year I should be able to begin... we shall see! I will be eagerly watching your progress with EG and learning all that I can.

When I have done fibreglass work in the past, i have found that adding tint makes it set slower, not sure why That was a liquid tint tho

You want a large speaker and glue a small platform to cone and pump a small frequency tone into it ..at that time you bolt the containers to it so it can vibrate the sample of air

Could you turn it on the lathe? To true it up. I wonder how it would react.

Hi! Can you make a video on your shaker table please. You can just show it and explain how you assembeled it? I like home made shakers, an have found some where the youtuber makes them from “scrapyard finds”.

Also besides kevlar, consider basalt fiber too.

I'm thinking lead or steel birdshot for filler

Make a vacuum pump from an old refrigerator compressor to de-gas the setting mix. Dump the epoxy mix into a plastic bag, cut one corner and use it like icing bag. Much easier to dispense the mix and minimises air pocket inclusions.

nicely done. Show vibrating setup, what thinking about it the whole time until you mentioned it.

Causually showering with my nuts and bolts.

Might be worthwhile lay in a thin coat without garnet, like a gel coat on a fiberglass form, let that set or near set, then put the epoxy with garnet mix.

I think you can use vacuum chamber to avoid air bubble !

For anyone interested in a deep dive of epoxy granite theory, checkout this very long old thread on cnczone.com/forums/epoxy-granite/30155-epoxy-granite-machine-bases-polymer-concrete-frame.html TLDR; Mix granule sizes to maximize desirable characteristics and minimize epoxy use.

Now I want brownies

I could be wrong but I can't think of a plastic that doesn't begin with "poly" Awesome video though! Thanks!

Why not remove the plastic mold with your lathe? And while you're at it, you could finish the rough edge till you see the magnet.

I found that in large quantities it was cheaper to buy the real product. There is a company here in Ohio that supplies it

Beer can and medication container are made for each other. What?

The mixture with thermal cast in place granite epoxy has like three different size aggregate. I think the larger size is close to 1/4 inch the. Smaller particular then smaller to fill in between all the aggregate ... just info from my research

Your epoxy percentage was actually 17%. Your total mass was 600 grams, and 100/600 was your epoxy ratio. Always remember it's grams of "solute" over grams of "solution." Not, grams of solute over grams of solvent. You want to divide by the TOTAL mass of the "solution." Also, you've got to mix the epoxy first. (Both parts together) before adding the garnet. The parts of resin that you mixed with the garnet first, will not come into contact with the hardener very well. All the pieces of garnet will have a coating of wet resin encapsulating it, which is then encapsulated by the cured epoxy that was able to mix thoroughly.

good first attempt ....but you should have coated the plastic container with pva mold release ,I also would have coated the the container with just clear epoxy ie bushed in or roll coat several coat let it set up for few hours....used heat gun to pop bubbles on surface before it sets up, once you walls are tacky, I would have mix epoxy and colour mixed only and roll coat the wall with this mix only.. no garnet....several coats....use heat gun as above...leave it to set up.. few hours then and only then mix epoxy with garnet power and use the vacuum chamber to degas it then vibrate your mix in.

Link your instagram in the description! Also to fill those surface pores in, could you just coat the exterior with another coating of a low viscosity epoxy?

13 ?

add some all thread and youve got yourself a tool cam mount.

not just different approach, you can use your imagination as well, you are a machinist, all machinist wil have some rusty bolts and nuts in the shop, you have a lathe, there must be steel shavings when you work on your projects. old bearing balls? all these can be use to fill. pour some epoxy, it can be as good as commercial products. besides that, how about sand? little rocks? glass marble? all these cost nothing or just peanut price. still not heavy enough? you can pour lead to replace epoxy. with some simple calculation, you can make hollow parts with any weight any centre of gravity and strength you want. for example, you can make a saw horse with 4 legs as metal tube. fill the bottom of the legs with steel shavings and pour a pound of lead in. you will have a saw horse that almost will not fall down, cause you change the cog of that tool. the same principle can apply to cnc machine frame as well. granite is not a must epoxy is not a must therefore, epoxy granite is not a must.

gentleman, we would rather see you back to the lathe or the cnc machine then see you mixing concrete..... hahaha well, you can try that on a different approach, you can use some wall socket box fittings, those little box that hold your ac socket on the wall, no matter it is plastic or metal, it is flat and square, fill it up to 90%, because the epoxy will expand a little bit when it dry up. the beauty thing is, those little box usually comes with a flat face, screw it on top and you will be a happy man. it is just 2~3 bucks a set and you don`t even have to think how to get the epoxy out, will save you a lot of trouble if you still think it is too expensive, how about a tic tac box? or a frisk box? it is square it is plastic and cost nothing

@1:42 Say That Fast 3 Times! 😂

Do not go sliding the abrasive garnet base around on important surfaces.

Coat the container with a thin amount of Vaseline.

I feel like you didn't try hard enough to split open a knuckle with the wrench whacks. Maybe you could try again blindfolded? And then Difficulty level 3, you could film it with your cellphone, while it's clenched loosely in your mouth, as you try to talk us through the process.

So....what's the point???

A vacuum chamber would had got rid of those air pockets.

the purpose of the TEXT Screen is to share with your audience. Most do NOT read at the Microseconds​ level you flash on the screen! Informative Video, detracted by poor timing of the Text Screens.

Enough with the CHEMISTRY lessons

I once read a message that said, what should not be heard by little ears should not be said by big mouths, maybe you should listen to that when narrating on a public seen video.