Frosted Epoxy Resin Clock

This time I’ll combine this nice elm burr piece with an epoxy resin to make a stunning frosted wall clock.

How I did it - you can check by looking DIY video or you can follow up instructions below.

For this project you will need:

Materials:

Elm burr ( or any other kind of figured wood piece)

Transparent epoxy resing for casting

Black pigment to dye epoxy resin

Hot glue

Osmo hard wax for the finish

Sandpaper: 80, 120, 180, 240, 320 grit.

Aluminum foil tape

Clock mechanism

Piece of melamine or plywood for mold base

Packing tape

Wood screws

Silicone

Tools:

Belt sander with 80 grit sandpaper

Band saw

Jigsaw

Palm router with the flush cut bit

Orbital sander

Drill and bits

Clamps and some other usual bits and bobs are laying around the workshop.

First things first, I need to cut a manageable piece that fits the best with the size of the upcoming clock. I'm planning that it should be 30 centimeters in diameter.

This burr is barck free already, so I brushed off all other loose parts.

The surface is clean and is ready to be covered with color. Instead of using an epoxy resin with a pigment I simply sprayed with chrome spray paint.
It may be that spray paint sealed the wood already, but I used epoxy resin and primed the whole piece to be 100% sure and to avoid any potential bubbles in the casting later.

While the epoxy resin was curing I made a very simple mold. A scrap piece of melamine was cut to a round base with a bandsaw. Then covered with packing tape which helps me to remove the casting from the mold later. Around the perimeter I used a polypropylene piece - because I had it in my scrap pile and it wont stick to the epoxy resin too. To make the joint watertight I sealed it with regular silicon.

Alright, time to mix some epoxy resin. I used a slow curing casting epoxy which is UV resistant and could be poured up to 10 centimeters deep. This is the same resin that I used in my epoxy LED night lamp

Well mixed and poured into the mold. Suddenly I was reminded that the wood isn't as dense as the epoxy resin and it floats. Somehow I forgot to glue the elm burr to the mold. Not a big deal - the situation was controlled by adding weight from above.

Here is the beauty of the slow curing epoxy resin - all air bubbles disappeared naturally. It is so clear that it’s very hard to tell how deep this pour actually is.

One week later the epoxy resin was rock solid and I removed it from the mold.

I don’t show anything new for a surface flattening - just a simple jig and router sled with a straight cut bit.

Made pass by pass until the unpainted wood surface was uncovered.

Drilled a hole in the middle and used a pin to center the paper template. This template has 12 marks which represent 12 hours. Marked those reference points on the surface and connected them with the line.

To mill each hour mark I made a simple jig for my palm router. The cut on the left will help to align and double-check before milling each new hour mark. Clamping, milling, unclamping, repeat.

When all 12 marks were done I changed the router template to another. This one allows milling longer and wider hour marks on 3, 6, 9, and 12 hours marks by using the same router bit.

With aluminium foil tape I sealed the edge and with hot glue made a small dam around each mark. Epoxy resin has an annoying tendency of shrinking upon curing. This dam will allow a small overfill which will compensate for that potential sag.

Mixed some epoxy resin with a black pigment and filled all grooves.

Here is visible that sag. If the overfill was too small, I will need to fill that spot again or take off additional millimeters from the whole surface.

Instead of working hard and sanding those overfills - I flattened them with the router sled.

Cut to the final 30 centimeters of diameter with a band saw because the mold was made a bit larger. Ruff bandsaw cut marks were sanded with a disc sander. And later on, finished by hand with 220 and 320 grit sandpaper.

Drilled a hole for the shaft of the clock mechanism and marked ruff outer shape. With the palm router and straight cut bit milled needed hole.

And it’s sanding time. I pasted through various grits by starting with 80, 120, 180, 240 and finished with 320 grit. From 180 I often wiped the dust from the surface during the sanding. This helped a lot to avoid swirl marks on the epoxy surface.

I call that a success.

I added a small chamfer on the edge for a more aesthetic look. This is the same palm router that was used along with the build, just attached to the Dewalt job site table saw. Very handy modification.

I was opening the oil can to apply a finish, but then I realized the hanging hole is missing - so milled a needed hole with the palm router.

And now the grand reveal of the final look. I used Osmo polyx oil for the finish. This is one of the two most popular products used on epoxy projects by the makers so far. I used a small amount of product and well buffed it into the surface.

What's left - to assemble everything in their place.

I used a cheap clock mechanism, but the silent one - which does not make that annoying ticking sound.

I could make this build way faster by using CNC for surface flattening, milling all grooves and pockets. But I wanted to show that the same result could be achieved by using a few basic electric tools, some imagination, and a few extra hours in a workshop. I hope this will be the right amount of inspiration to try it by yourself.