I have always found the epoxy they use to make table tops and bar tops interesting. But I have never had an excuse to use it, so I thought up a few projects that it might work for so I could try it out. It turns out is quite an interesting product and has much broader uses than just table tops. Well, I actually thought of the projects first and then wondered if epoxy would work for them so really this is another big experiment. Some things didn't go as well as I had hoped. Others turned out really good.
And it all started with the band saw and a bunch of weird wood.
Step 1: Slice and Dice
This spring I thought I would try out a new bandsaw blade and so picked up a bunch of wood that had been lying around for a few years and sliced it up. The more I cut the more fascinated I became and the next thing I knew had a pile of these amazing pieces of wood. Sometimes the adage of beauty being on the inside really proves true. Some of this wood looks like junk outside, one piece even looks like something from a litter box. Yet inside they are amazing. I started to think about things I could make with them. Elm slices have amazing color and grain. I had some that were pretty gnarled with knots and holes in them. But sometimes a hole is an opportunity to fill rather than something missing. So this crazy idea happened, to put LED's in the holes and fill the gap with something like glass that would transmit the light and then glue the entire thing together with epoxy. Why not give it a try?
Step 2: Going Green
An important thing that I considered when picking the LEDs for this project is how hot they get. Since these are going to be encased in epoxy they will not be able to cool off if they generate a lot of heat. So the LEDs that I used are relatively small ones. I left them on for an hour and they were just a little warm so I should not have a heat problem with them.
I started out using just white, which is what the olive one has but couldn't help wonder if adding a color accent would look good. So I tried adding some green to this one.
You might recognize this as being the elm slice that homer had possession of. He got tired of it pretty fast so I rescued it.
I did things differently with this one as compared with the other. After I completed the olive I liked the overall result but some of the LEDs shown through the glass very brightly. The ones that looked better I thought were the ones that were behind or concealed more so the light reflected through the glass. I decided to try to place the LEDs in better spots to get a better light pattern. So I started by only putting in half the glass and doing a beginning pour of about half epoxy.
Using a Dremel I cut channels for the wires and also cut slots to fit the LEDs into the wood. Then I added more glass and filled in the rest of the epoxy.
Step 3: I Like the Green
I think the LEd placement idea worked out well. You can see the difference in the front and back pictures.
Mixing in another color also adds some highlights that are a nice effect. Some of the green light reflects off of the glass at the far side so there are little green sparkles in with the white. The solid green knothole looks a little like an emerald. It's a nice effect overall.
I might add some hooks to the open areas and turn this into a night light key rack.
What do you think?
Step 4: Have a Heart
I ran across this interesting piece of elm and thought that it would be worth trying to preserve. I looks like it has a heart. Interestingly all trees have hearts, that is what the middle of the tree is called. it's a play on words, yes.
The wood was nice and dry but it had started to fall apart and the bark was flaking off. I wondered if epoxy could fix it.
Turns out it works fantastic for this. The epoxy hardens very slowly so it gives it time to soak into the wood. In fact it runs down into every little crack and it actually soaks into the wood fibers. This gives the wood a wet look. In darker woods the color can become very dark. Once hardened the epoxy becomes part of the wood and holds everything together. So if you have a piece of wood that has some rot and you want to fix it, run some epoxy into it and let it set up. It becomes harder than the wood itself. It just takes a long time to cure.
Step 5: Adding a Caption.
I thought I would get a little philosophical and add a caption, after all I already took steps to preserve this piece, lets go all the way.
I printed out a little message with a laser printer and arrange it to fit on the wood. Then using a wood burning attachment I transferred the image to the wood from the paper. This can get tricky. If it is to hot the paper will scorch. If you don't use enough pressure the image will not transfer completely. It might take a few times to get it right. if you make a mistake you just sand it off and do it again.
My son looked at the progress and suggested I find some way of enhancing the area of the crack around the heart. So I decided to try filling it with some bits of plastic from a disposable florescent plastic bowl. It worked pretty good. I put broken glass on top of it to help keep it from floating in the epoxy.
ABOUT THE GLASS
I used broken tempered glass from a car window. This glass breaks into tiny little pieces. This was perfect for my uses since the broken glass fit into the small spaces in the wood. Breaking it up didn't require anything like a hammer, just some mini pliers. If you try this keep in mind that the little pieces are still sharp and can get stuck in your skin so handle with caution. You should use tweezers or little pliers to handle it.
Step 6: One Down
This gnarled elm required multiple coats of epoxy as most woods like this do. The epoxy does not shrink but it does fill in low spots first. So in order to get a flat top you have to build it up until all the low spots are filled in.
I had a few disappointments with this one. The first was that the lettering from the laser transfer became hard to read when the epoxy was put on it. I thought it would show through better. I think it was because the elm wood itself was so dark. It should work better on lighter woods.
Next, interestingly, the glass kind of disappears in the epoxy. Not unlike marbles in a fish tank, the epoxy hides the glass unless you look through it. So, while broken glass is all sparkly, glass in epoxy is hard to see. I suppose glitter would work better for reflecting light. But light shining through from behind does show the glass, whereas glitter would show up as just dark spots. .
There is a little light that can come through from the back of this project but it has to be a strong light before you can see inside the heart crack.
My son's quip on that one --"Why would you want to put glass in your crack anyway". Grrrr .
Step 7: How About Some Hooks.
One of the things I thought of making with my wood slices is key racks. I have had a need for one for a long time. I used to use a stainless steel bowl to put keys in but the cats kept knocking it over. So I need a key rack. A few hooks and a slice from a tree limb and I should be good to go.
The piece in the picture is a slice of an elm branch. Its a very distinctive look. I put a coat of epoxy on it and it looked great. The plan was to put the hooks in and put on a second coat with them in place.
I pre drilled the holes for the hooks and screwed them in. Simple!, not. Elm is a hard wood. Brass is a soft metal. In spite of me pre drilling holes, one of the hooks snapped off as I was screwing it in. OK, I have now ordered brass coated steel hooks. So if you want to do a project like this, brass is fine in soft wood like pine but use steel hooks in hard woods.
Step 8: Make Things Glow
This is a slice of Russian olive that I thought has some interesting holes in it from knots. A perfect place to try and add some light. Using LED's and hot melt glue, I placed the lights where I thought they would work the best. By the way, these are 12 volt pre-wired LED lights. They are really inexpensive when bought in bulk on eBay. These knots holes were open on the bottom and closed on the top so I put tape over the top and filled them with glass from the bottom. This actually worked pretty good because it kept the glass flat across the top with no pieces sticking up. I used hot melt glue to build up a dam to keep the epoxy in where there was no wood. This worked better than I thought it would. I put the tape on top first and then put the glue on the tape where I needed it. This made it possible to pool the epoxy in the glass in places that didn't have wood for a border. Once it is set the epoxy supports itself.
After the epoxy cured I used a hair dryer to heat up and remove the hot melt glue, dabbing it up with a paper towel when it melted. I have to remember this trick as I could see it being very useful. Essentially you can make a mold with hot melt glue, fill it with epoxy and then melt the glue out, especially since epoxy isn't bothered by the relatively low heat.
So, I turned the olive upside down and poured the epoxy into the knots and let it set. Then removed the tape from the top and finally put a top coat on top after I had removed the hot melt glue dam's.
Step 9: Results
I was very happy with the finished results of this piece. It puts out a fair amount of light and the effect of the glass is very nice.
I haven't decided its final use yet though. I could just use it as a night light, wall decoration or I could put some hooks in it and use it for Keys. I have to think about it some more.
Step 10: Refinements
I decided to cut channels to run the LED wires in as it both provided protection for them and kept them all together. But I ran into a problem with the LED leads on one end. They could not be bent because they had resisters in the leads. SO they stuck out past the end of the wood. The simple solution to this was to just build out the end of the wood with more epoxy and glass so the wires were protected and hidden in the glass and epoxy.
This was not to difficult to do since I had figured out how to make forms for the epoxy with the hot melt glue. The pictures show the process. It work really good and made the overall piece look even better. I really liked the effect. It took several more coatings to get everything filled in and then one final coating for the top. The effect of the finish is amazing. It looks like water. The camera had a hard time focusing because it kept trying to focus on the reflection rather than the wood. The over all effect is both visual and tactile. It feels good in your hand because it is so smooth. You almost can't resist touching it. You almost expect it to be wet.
By the way -- I switched to a different glue gun and different glue (a smaller one) and this glue just peeled off from the epoxy. I was really happy with that. So how easy it is to remove the "mold" depends on the hot melt glue you use.
Amazingly, in terms of cost the epoxy is turning out to be less expensive than conventional finishes. The cost of a gallon of polyurethane is going to be around $40 to $50. The cost of a gallon of epoxy (2 half gallons that you mix to make one gallon) is about the same. But it only takes a few coats to get this amazing finish with the epoxy while the other has to be built up and sanded in layers. The epoxy is also totally waterproof, something many conventional finishes are not. In the end the epoxy is cheaper, more difficult to work with, but much better results for some things like this.
Step 11: A Few Words About the Epoxy
This epoxy coating comes with extensive directions which are located on the companies web site. The QR code takes you right to them. But the directions are assuming you are doing large surfaces and using 1/2 gallon or more. To do small surfaces you have to scale the thinking down.
I used little paper drinking cups for my mixing and measuring. I put a pencil mark on the inside of the cup so I could get the amounts correct. Don't use magic marker, I found out that the epoxy dissolves the marker and it goes away. Pour the thicker half of the epoxy in first and let it level to the mark. Then pour it into the mixing cup and scrape the sides and bottom to get all the thick epoxy out. I didn't do this once and it messed up my mix ratio because to much of the first one was left in the measure cup. This caused the epoxy to take forever to cure and it stayed a little flexible. I had to put another layer on top to get it to be hard. Measure out the second half into the cup and then add it to the first part and start mixing. Because it is a small amount it is an easy job to mix completely, but you have a lot of time here so just mix it and mix it to be sure it is done right. By a lot of time I mean hours. It takes hours before this stuff becomes unworkable. So take your time.
It has the consistency of honey. It runs. It sinks into every crack and leaks out of every tiny hole. It self levels, with gravity. So if your table is not level your epoxy coat will not be level.
Because it takes a long time to cure it stays fluid and flow-able for hours. That can be a problem.
It stays sticky for hours also, so anything like cat hair that lands on it will become part of it.
And another thing about the paper cups, after a while the epoxy starts to work its way through the cups fibers so they get all sticky on the outside.
Amazingly, I found the perfect place to put things while they are curing. --- In my oven.
Am I crazy? Really this works really good.
First, if you warm the epoxy to 80 it sets faster, 90 or 100 I found is even better. But if you get it to set to fast the bubbles will not make it out so let it sit for an hour first. In the meantime turn the oven on to its lowest setting and let it get warm. Turn the oven off and put the cardboard and epoxied items on the racks in the oven where they can get warmed up. There is no dust in the oven so that problem is taken care of. Most ovens are level, so the epoxy will set level. If your oven is not level you can adjust it so it can be. It is the perfect place to cure the epoxy. BUT do not turn the oven on again with the cardboard on the racks. DO NOT forget this. You could burn your house down.
To prevent the epoxy from running off all over run tape on the bottom edges. Epoxy does not stick to tape so you can remove the tape after it is set. If it runs off the edge and then sinks into the cardboard it will glue your stuff to the cardboard and it loves to stick to cardboard. So use tape liberally to control where the epoxy goes until it is hard.
There is a little learning curve to using this stuff so do some trial runs first. Get comfortable with it before you move into your good projects because there is no way to undo epoxy.