Epoxy pour done

The bases have nice stony feeling about them!

Pouring update

The first pour has hit a trouble. The form got a bit distorted, presumably from the heat of epoxy curing. So, to prevent more distortion, I'm doing the following steps:

1. I'll pour in layers. Each layer produces less pressure, so will distort less. Also, the amount of heat generated by a layer will be easier to dissipate.
2. I'll mix in a lot more sand. It makes the mix harder to pour, to the point where it barely flows if at all, but the amount of heat is again, smaller.
3. I'll add a lot more structure into the forms, so that even if the plastic becomes soft, it will hold shape better.
4. I've added a step at the edges of the leg bases, so even if there is some deformation, it will be hidden away.

To pour in layers, I printed all the parts, so that one batch fills about 3cm of depth. Here are the results of the first batch:

Update: all the XY ends done + small improvement

All the XY ends are printed, ready for installing.
After some thought, I reversed the direction of M8 bolts. Now the bolts sticks from the inside out. This has several advantages:
1. Nothing inside the plastic part has to rotate when I'm tightening  the nuts. So it's much easier to assemble and disassemble.
2. The structure is less sensitive to the bolt size.
3. I think the nylock nuts look way nicer than bolt heads.

Printed the XY ends

Everything fits (well almost):

- The retainer must be some 2mm deeper for the M8 bolts to not to stick out into the slider.
- The stepper mounting plate has a round protrusion that I forgot about, need to make a corresponding hole for the motor to sit tightly.

Otherwise, it is all tight and rigid, everything fits precisely.

Pouring the epoxy and next steps

Mixing and pouring epoxy is simple. But there is one but. Epoxy may seem viscous, but it will go through the smallest of cracks.

So after I poured it, I had a fun session where I ran around with a hot glue gun (thanks whomever necessary for that invention) and plugged the links. Finally, it slowed enough that I could let it dry hoping that something will remain inside. Here it is:



The next life saver was the Fein Multimaster.

1. The spools of epoxy, which I tried to sponge out with wads of paper became a mess of semi-hard papier mache. Didn't succeed to tear them off, so I just cut them out.
2. The edges of the surface weren't flat because of the surface tension. The multitool made an easy task of sawing them off at 45 degrees.

And here is the end product:



Added legs (see the remains of silicon, glued to the frame with epoxy) :( .



The next step is assembling the linear guides. The material is already here.

Straightening the CNC plate - preparation

The metal frame is bent, and very hard to straighten back. So the idea is to pour a layer of epoxy on it to create a flat surface.

3D printer

Assembly of my Prusa (done Sept 2):

My CNC

For a long time, I'm trying to assemble the MPCNC machine http://www.vicious1.com/ Here I'll post my notes.