Coffee Floats

[Chasper]

Casting coffee beans is giving me fits, the beans float. The problem is that they float to the surface and the bottom of the mold is nearly all resin, the top is mostly beans, I want them to be evenly distributed.

I've tried soaking them in un-catalized resin for a month, they lost some boyancy but still float a little. I've tried putting a lid on the mold and they float up to just under the lid. If I put so many in the mixture that they are pushed all the way to the bottom under the lid, then they are too close together in the final casting. I want them to be spaced out and evenly distributed.

What if I poured a shallow layer with evenly distributed beans and let it semi harden, then another and another, etc until the mold is full after 4-5 layer pourings? Can someone offer a better solution?

 

[Seer]

That is how they pour for freeze dried critters. They fill it to where they want the critter to be and then let it set and fill up the rest.

 

[MesquiteMan]

Add more coffee beans? I don't do coffee beans but I do other things that tend to float and I just use more of the said material until I have enough that it all stays down. If that does not work for you, then you could try peg board cut to the size of your mold. Pour the resin, add the beans, then cover with the peg board. It will hold it down, at least it has on the stuff I have done that is at least as buoyant as coffee beans. then when cured, just cut into blanks and cut off the peg board.

 

[beck3906]

That is how they pour for freeze dried critters. They fill it to where they want the critter to be and then let it set and fill up the rest.

Freeze dried critters?

Okay, I'll bite. What are they? Forest creatures come to mind first.

 

[Padre]

You need to put another mold on top of the resin/coffee bean one. I had the same problem, so I took the first mold and put it in the pressure pot, put another mold on top of it and then put some scrap wood on top of that. It worked great. You can read my asking the same thing here.

 

[Seer]

No they are dead insects that they dry so they can seal them in epoxy. Not to tasty even when starving at least to me lol

 

[mywoodshopca]

Make a block the same size as the in side of your mold.. cover with saranwrap. tape down.

Heres my process:

1. fill beans up to where I want (usually 7/8s or so for 3/4 blanks)
2. shake beans down to make sure they are packed well.
3. mix up the alumilite/resin
4. pour in
5. push the block down on top and then wrap a strip of tape across to keep the block tight to the beans.
6. let harden

Be careful you dont use too much resin otherwise when the block takes up the space inside your mold, it will be squished out and make a heck of a mess..

 

[its_virgil]

There is an article in the library outlining how to cast coffee beans...at least I think there is. It was written by our down under friend Serge.
Do a good turn daily!
Don

Casting coffee beans is giving me fits, the beans float. The problem is that they float to the surface and the bottom of the mold is nearly all resin, the top is mostly beans, I want them to be evenly distributed.

I've tried soaking them in un-catalized resin for a month, they lost some boyancy but still float a little. I've tried putting a lid on the mold and they float up to just under the lid. If I put so many in the mixture that they are pushed all the way to the bottom under the lid, then they are too close together in the final casting. I want them to be spaced out and evenly distributed.

What if I poured a shallow layer with evenly distributed beans and let it semi harden, then another and another, etc until the mold is full after 4-5 layer pourings? Can someone offer a better solution?

 

[RAdams]

Check out the Horizontal round molds i just made. There is a thread about them, and the pics are in my gallery. I am going to write a tutorial on how to make them soon. They would be perfect for casting coffee blanks! The mold is horizontal, so you have access to the length of the blank when pouring. The top is just a slit to allow the resin to flow into the mold, so it would automatically hold the beans in for you.

A link to the thread

http://www.penturners.org/forum/showthread.php?t=61298

 

[Glass Scratcher]

You could always vacuum the resin into the beans. That is how I do shredded currency I vacuum the un-catalysed resin into the shreds, then pour in more resin to refill what was absorbed by the shreds and add MEKp. After mixing pour into molds, and pressurize. You may still have to cover the mold somewhat. Postcure after removing from pressure to ensure that the resin that was vac'd will cure.

We are talking PR casting aren't we?

 

[RAdams]

You could always vacuum the resin into the beans. That is how I do shredded currency I vacuum the un-catalysed resin into the shreds, then pour in more resin to refill what was absorbed by the shreds and add MEKp. After mixing pour into molds, and pressurize. You may still have to cover the mold somewhat. Postcure after removing from pressure to ensure that the resin that was vac'd will cure.

We are talking PR casting aren't we?

I sure am glad you said that!!! I recently got a little bag of shreds and have been trying to figure out the best way to do them. Now i have somewhere to start! Now i gotta take the wifes vacuum cleaner apart!

 

[Glass Scratcher]

I sure am glad you said that!!! I recently got a little bag of shreds and have been trying to figure out the best way to do them. Now i have somewhere to start! Now i gotta take the wifes vacuum cleaner apart!

Er, no... You really need a vacuum pump, to take it to 25" Hg, then let it percolate for a while.

 

[skiprat]

If you want gaps between the beans then how about CA'ing them to a straw or thin wood dowel. The cast, then drill out the straw / dowel for the kit tubes?

 

[Ankrom Exotics]

When casting coffee beans I make a makeshift, disposable wood frame that just fits within the dimensions of the mold. I cover 1 side with plastic screen, staple it tight and place it over the beans and resin. I just use super glue to join the frame as it only needs to hold together for a short period of time. The frame sticks up over the edge of the mold after the beans are in place and I wrap it a couple times with masking tape to keep everything from floating to the surface. Entire time to construct and utilize? Maybe 10 minutes. Not reusable.

 

[RAdams]

Er, no... You really need a vacuum pump, to take it to 25" Hg, then let it percolate for a while.

That was just a joke...


But i am thinking about getting a couple of old microwaves and making a homemade welder!

 

[Dai Sensei]

I scored a rectangular silicon cake mold from one of the $2 shops. I made a simple box from thin strips of timber 3/4" high and CA that fitted inside leaving 2 1/4" wide inside. I then used some thick CA to fix some plastic flywire on the top. Holding the box upside down I fill it with beans and place the mould over the top then invert everything. I then pour in the resin.

After setting I simply cut the box off on the bandsaw, but with simple timber shims, can use the box again (with new flywire screen of course). I get 8 no. 1/2 blanks per cast. I also stabilize my beans before casting.

 

[ribanett]

Expanding on what Curtis said in post #3. I cut a piece out of old priority mailers, about 1" larger than the mold and put 5 or 6 holes in it with a paper punch to let any excess PR to come out. Put a small weight on it. After curing, just cut into blanks and turn-off the cardboard

 

[KDM]

What if I poured a shallow layer with evenly distributed beans and let it semi harden, then another and another, etc until the mold is full after 4-5 layer pourings? Can someone offer a better solution?

Hope you got this figured out, but what you say here is exactly what I do. It's worked perfectly for me several times.

Word of warning: if you're colouring your PR (I use a sort of latte colour) make up your entire batch of coloured resin in one go, but only add MEKP to a small batch at a time. Otherwise, you'll never match the colour perfectly. If you're using a pale colour, make sure you use EXACTLY the same amount of MEKP per layer as I've experienced colour changes which I can only put down to a change in density of the material. It's particularly obvious when casting clear resin.

 

[Bowl Slinger]

Ive had success with gluing the beans to the pen tube. This way I can place the beans where I want them. Then I cast it in resin.