Your Projects

Extra photos from last post

Originally posted by krankin 06-17-2019

We started nearly a year ago on this project to make a laser cut topographic map encased in epoxy resin for my friend Elliott Overhoff as a table surface to go over his Ottoman. Elliott provided the design based on the city map that is freely available in .vector format through the city of kamloops's website. Once we had that we wanted to do a test on paper to get the scale right.

Once happy with the scale and after playing around with the building we wanted to include (we removed most of them in an effort to save time on the laser cutter) we proceeded to cut and glue all the layers together.

Next came sealing in order to prevent bubbles come the epoxy resin pour, and thus the first major lesson learned on this adventure of a project. Make sure you seal the wood completely. I just used some epoxy resin brushed on to seal it, which worked well, as the epoxy doesn't cause any bubble causing off gassing of the wood when it is only a thin layer. however i learned later on that i should of been more liberal in my application of my seal coat as there were still several points that bubbled when we did the epoxy pour.

Then came the exciting part.the pour. We made the form out of melamine coated particle board screwed together to allow for easier disassembly, also make it several inches deeper than you need it to be. This will help later with disassembly. You should tape the bottom seams of your form with tape to prevent leakages. masking tape will work however you can use tuck take to make a surface that the resin wont stick to if you are filling a gap/ seam that is going to be on a finished face of the project. You always want to make sure that your form has a non-porous finish on it or else you wont be able to bet it off your epoxy project in one piece. Epoxy resin is often used as a glue in industrial settings. its very good at sticking to things once it soaks into them. don't give it that opportunity.
You should also elevate your form above the table on some blocks placed at least 3 inches away from the edges and seams. This is to make sure that even if there is a leak, you don't accidentally epoxy your form and project to your table. It is also worth putting down some paper or tarp on the table surface as you will get it messy with epoxy.

With the pieces in place, it was now time to do the pour. We wanted the river to have a deep green colour to it so we added a few drops of universal pigment to the epoxy mix and the poured the first layer that would be the rivers. you will see that we have a bunch of weights on the wood sections. That was because the plywood still have a bit of a warp and bend and we wanted to make sure that the "water" level was going to be flush with the shore and not have the shoreline bowing way up above the water. Once the first pour of epoxy was cured, its adhesion to the bottom of the form was enough to hold it down so the weights would not be needed for the rest of the pours.
we then let the epoxy cure for around 3 hours to cure before doing more layers as the above epoxy was to be clear and we did not want colour bleeding from the river into the epoxy above. We should of left it a few hours longer as there was still some minor colour bleeding, but we were on a bit of a time crunch.

Once we did the big flood pour, we were faced with some bubbles floating to the surface. Some bubbles is to be expected and is just a result of some air getting mixed into the epoxy. so long as you do fairly thin layers, this is ok and you can get rid of them once they float to the surface with a heat gun (an hair drier on high heat would probably work as well) or the more fun option, with a gas torch. we used a little butane torch because fire is fun. However it is important to apply the heat in steady passes over the epoxy. the heat will cause it to cure faster as well as can actually cause more bubbles as if you heat one area to much, the wood will heat up and off-gas more.
This is the stage when the errors of my improper sealing started showing up. and bubbles were a forming making nice little columns of bubbles in what was supposed to be crystal clear epoxy. Lesson learned. SEAL THE WOOD WELL. DO NOT BE FRUGAL WITH THE SEAL COAT.
most of these i believe are parts of the wood off-gassing as they soak up the epoxy resin, however i think some were also caused from some rough points in the seal coat that acted as nucleation points that bubbled formed curing the chemical reaction that takes place as the epoxy cures. These bubble spots resulted in columns of bubbles in the epoxy after it cured.This was going to be a problem we had to solve later. but at this point all we could do it leave it and let it cure for 24 hours.

after it cured we then had to take it out of the form. so you unscrew the form and remove the tape you put to seal the seams. However, the epoxy is still a very good adhesive, even against a non-porous surface. This is because there is no air gap between it an the form walls/ floor so you need to break the seal fist. this might require i wedge, chisel and hammer. NEVER hammer directly on the epoxy. You will leave scuffs and damage. Use a scrap piece of plywood and some towel on the resin where you want to hit if you must hit near the epoxy; and always try to hit the form rather than your project. This is where making your form deeper than you needed comes in use. A: you have more surface area to hit, be you have more leverage making it easier to come off the epoxy.

IMG_2989.JPG
It was here where i discovered another mistake.Despite making the form to fit our dimensions, It seemed that when we glued our wood layers together, they were ever so slightly out of alignment and made it slightly bigger than the form, thus resulting in an air gap underneath the map... The result of this was that the piece now had a large curve to it, made worst by the fact that as the epoxy resin cures, it shrinks slightly which pulled the map inwards curving it further, as well as providing an air gap for epoxy to flood and air to vent out causing bubbles along the edges.
The gap did however make it easier to remove from the form floor though.

So, we had to build up the bottom with more wood to flatten it off. And in order to deal with the many bubbles we decided to drill them out and refill. (they tend for form from the same spot so you get little bubble columns in the epoxy, so you can drill out the columns). You can still see an outline of the holes from where we drilled. But it is less noticeable than a column of bubbles. We tried to get the walls of the holes as smooth as possible by sanding with fine grits to minimize any trace of the hole. Once we had that done, we poured some more epoxy over it to level out the top surface as it was still pretty curved from the first pour.
IMG_3425.JPG
a ghost of bubbles past. The remnant of a column of bubbles after being drilled out and refilled. this was probably the most noticeable of the bubble we drilled out. The more you sand and the finer the grit you use, the less remnant there will be. but you don't have to get it mirror smooth if your covering it with epoxy. the Epoxy will will in some roughness.

There was still however some problems with this pour. We still got one spot that bubbled a bunch (I drilled deep enough to get to a air pocket deep underneath, but not deep enough to open it enough for the epoxy to fill it properly.) and one of the batches wasn’t mixed enough so it produced a few sticky and tacky spots. So we had to once again drill out the bad spots and refill.

Now this leads to the final problem. Due to having some irregular spots from different pours and sanding out the bad patches, the surface was pretty irregular. So rather than having some patches with a more satin finish from sanding and buffing and having the rest a glossy water like clear, we decided to sand it all and polish it the best we could. We went up to 2000 grit sandpaper and then car polish and wax. It’s pretty good. But it wasn’t enough to get to the water-like clarity that the untouched epoxy is like. I’ll need to invest in higher grit sandpaper and probably a buffing wheel as well for future projects. But my friend was happy with it so we called it done and it is now sitting on his ottoman allowing him to have a hard surface and kickass piece of furniture.

The finished project. The finish was good, but still a little more satin than gloss so it does look a little blurry but not too bad. Other finishing touches we did was sand a 45 degree bevel along all the edges, this is a simple touch that makes it so much softer and nicer to handle.


Big thanks for Elliott for funding this adventure and working on it with me. It was a blast, despite the blood sweat and tears that went into it.