I wanted to experiment with epoxy and bring all my skills together for one project. Pretty stoked how awesome it came out :-)
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Step 1: Materials and Tools
Below are all the tools and materials I used for this project - good luck!
- 8/4 Walnut
- Total Boat Deep Setting Epoxy (1 Quart)
- Oil Based Polyurethane
- 5 Minute Epoxy: https://amzn.to/2MYlWM6
- TiteBond II Wood Glue: http://amzn.to/2peRFus
- SAWSTOP Contractors 30” Saw: https://amzn.to/2Luh91q
- Table Saw Sled: https://amzn.to/2t2qVjD
- Taper Jig: http://amzn.to/2oGYBi0
- 6” Jointer: https://amzn.to/2Y7THgb
- 13” Thickness Planer: http://amzn.to/2u7YrmK
- Miter Saw: https://amzn.to/2YXsyRi
- Plunge Router: http://amzn.to/2p15eiC
- Orbital Sander: http://amzn.to/2oICOaP
- Power Drill: http://amzn.to/2q1l5wn
- Impact Driver: http://amzn.to/2q1l5wn
- Sand Paper - 120 - 1500 grits
- Speed Square - Tape Measure
FILM / EDIT EQUIPMENT
Step 2: Milling Lumber
I was using 8/4 Walnut for this project - rough sawn on two sides, so I began by jointing an edge (Pic 1), squaring up the second face (Pic 2), and cutting to length (Pic 3).
I then marked the center of the milled piece (Pic 4), lowered my table saw blade (Pic 5), and used my table saw sled (Pic 6) to make relief cuts in my piece of walnut. The goal of this was to make it easier to break the piece of walnut down the line - more on this later.
Step 3: Breaking the Lumber
Turns out breaking a piece of 8/4 walnut is tough. After cutting relief cuts in the piece, I did everything in my power to break the material.
I smacked it with a hammer (Pic 1).
I ran over it with my truck (Pic 2).
I gave up.
I ripped the big piece into individual strips (Pic 3) and then jumped with my full weight on the kerf and snapped it in half (Pic 4). I think a sledge hammer would have done the trick from the start. I then cut each piece to an arbitrary length (Pic 5) to make the legs different lenghts.
Step 4: Building the Mold
I used 3/4" melamine to build the mold. I ripped a base piece (Pic 1), followed by edge pieces (Pic 2). Melamine is perfect for casting as it retains liquid, is cheap, cuts very well, and is super flat. I used pocket holes (Pic 3) to secure the walls to the base.
I learned some time ago that using packing tape (Pic 4) is the way to go with moldings if you want to try to reuse them and help with releasing the epoxy. It worked very well. 10/10 would recommend to a friend.
I then lined everything up with the walnut pieces and the border pieces (Pic 5) and clamped pieces up so that I could flip it over (Pic 6). As you can see - I left a 5-6" gap between the walnut for epoxy to fill the voids.
To seal off epoxy joints, silicon is the way to go (Pic 7). I spread it on all the under surfaces, but in reality, I wish I would have put it anywhere where I didn't want epoxy to leak. It was fine, but silicon is your friend here, so overdoing it on all edges where epoxy should be pooled is the way to go.
I then used pocket hole screws and regular screws (Pics 8-9) to secure it fully to the mold, and cleared out any excess sawdust with my compressor (Pic 10).
Step 5: Epoxy Casting!
I used Totalboat Deepset Epoxy. It's a 3-1 ratio of mix to hardener. You can pour small moldings up to 2" deep.
This process was simple - pour 3 parts mix, 1 part hardener. Mix for 3 minutes, transfer to another container, mix for another 3 minutes, and pour. You have 30-45 minutes of working time, and if I had the resources, the one thing I would add to this is a vacuum chamber to remove all air bubbles.
I don't own one, and Deepset epoxy is thin so it leaves a relatively bubble free pour, but just dropping the tip here!
Step 6: Making the Seat Pt. 1
The seat was relatively simple.
I milled up additional 8/4 walnut I had + padauk scraps to form the top. This mean ripping on the table saw, cutting to length on the miter saw, and then laminating together using Titebond 2 glue and clamping up.
You can see that I cut things in the rough shape of a circle so that I could utilize the most of my material. No idea why I didn't cut the padauk to width before laminating...
Step 7: Making the Seat Pt. 2
The next day, after the glue cured, I ran the whole piece through the planer.
Then I found the exact center of the piece so that I could begin building the jig for cutting a circle with my router.
I cut out a dowel on the miter saw, drilled a corresponding hole in the bottom of the stool with a forsner bit and a piece of scrap redwood, and attached my router to it so that I could spin the router with a straight bit around the seat to make a circle. It worked like a charm.
I then cut off the excess material on my band saw.
I could then take the top to my router table and use a flush trim bit to cut off the excess material and flush up the sides completely to the circle I had routed before. Before heading to sanding with my orbital and hand sander, I used a 1/2" round over bit to complete the design of the stool and make it cozy on my tooshie.
Step 8: Leg Shaping
For reasons I'm not sure, my epoxy pour cracked. My hunch is that the temperature in my shop was too hot and the epoxy overheated, leading to deep cracks.
De-molding was quite easy. I cut a wedge with the excess walnut I had and hammered it underneath the piece and it slowly raises up from the tape/molding. 10/10 would recommend.
I then used my taper jig squared up to the blade to rip off the excess material from the molding. It started to look super clean suddenly! Once I had a flat surface, I then ripped the material back into individual legs - three of them, and then did a series of consecutive passes without moving the fence to square up all there legs to the exact same size so I had three identical legs.
Step 9: Fixing My Mistakes
The cracks in my epoxy pour were far too severe.
I took the step to break them further at the surface so that I could squash the issue at the source.
Using some $4 5-minute epoxy, I could mix up, apply to the surfaces of the broken pieces, and then clamp things up for 60 minutes (double the max epoxy cure time for this adhesive), and repair the cracks.
And damn did it work well! Solid structure and you could barely see the breaks anymore.
I then finalized squaring things up on the table saw so I had 3 identical legs that were all solid pieces.
Step 10: Routing, Sanding, and Buffing the Legs/Epoxy
My legs were cut so that they were 1" thick both ways, so I could take them to my router table and use my 1/2" round-over bit to round over each edge. This helped negate my lack of lathe! I think an alternate design would be to taper the legs and keep them squared off - I think the mid-century modern design of those legs would be SUPER dope.
I then worked my way through the sandpaper grits with wet and dry sanding to work over the epoxy. I did the following grits:
In reality, I think using micro mesh pads would obviously be a good next step after this, but it was quite clear after the 1500 grit. Note - most of this was hand sanding, and I used acetone in between each grit to get rid of the wet and dry epoxy dust.
I then set up a jig on my table saw sled to cut a flat reference on each leg - this was quite simple and safe, it just required a bit of time to set everything up. Safety is always my concern.
I then used a polishing compound with a tiny polishing drill bit on my drill press to buff out the legs. The final picture shows you a before/after of the leg at 1500 grit v. plastic polishing. I'm told that micro mesh, using a vacuum chamber, and also using automotive polishing would all help take the clarity up even further. NEXT TIME!
Step 11: Making the Leg Base
I used left over walnut to cut narrow strips (about 5/8" wide) on the table saw. These pieces would eventually line up underneath the stool at the center and attach to the legs and the base to form the final piece.
After ripping the strips, I rotated the blade to 5° to add an angle to the outside of each strip - this 5° would determine the angle at which the lengths would come out of the base of the stool. I then cut them to their final length on the miter saw.
Using my table saw sled, I angled it at 30° and cut 2 x 30° on the tips of each piece that were not the 5° edge so that all three pieces could come together in the center. I was really impressed at how clean the joint turned out underneath.
Step 12: ASSEMBLY
Final steps now!
Using more 5-minute epoxy, I first attached the base pieces underneath the stool, centered them, and used a heavy oversized hex nut I had to hold things down for 30 minutes while the epoxy cured.
I then used the same epoxy to adhere a single leg at a time to the base. I was careful to put epoxy on all surfaces that would adhere to each other for maximum coverage. I knew this wouldn't be enough to create a joint that was secure, so I took it one step further.
I used a forsner bit to recess a 1/2" hole laterally into each leg, then drove in a 3" wood screw into each leg. This helped reinforce the epoxy joints to the stool and tighten up the joint overall. It was damn strong. Trust me.
I then used a 1/2" dowel to plug the recessed hole with wood glue, cut it off with my flush trim saw, and then used my orbital sander to flush everything up smooth. I also sanded everything down one last time and removed any excess epoxy that spilled over in the final glue up.
Step 13: Finishing!
Finishing was as simple as it goes.
First, I cut my legs to final length for the ideal height of my own stool using the table saw sled and my table saw.
I cleared off all excess dust using some compressed air, and then applied a thick solid coat of oil-based polyurethane to all surfaces of the chair, including the legs, base, and table top. The poly also helped bring out the shine a little bit more in the epoxy.
Step 14: DONE!
Hope you enjoyed the project. Final photos above! I highly suggest watching the video (pasted below again) as it helps better elaborate on everything I outlined in this article.
As always, thank you for reading! I would be so grateful if you could please subscribe to my Youtube Channel for future projects.