Epoxy question

[Paul Sook]

i have a really cool Burl that I want to totally enclose in epoxy. I am guessing it will make a 6x6 cube. Then I want to make a bowl out of it so a lot of it will be turned away. I am really struggling figuring out what kind of epoxy to use to pour up 6”. I have a box built to set the Burl in and fill with epoxy. I tried it once with a 2 part but the epoxy never really got hard I am guessing because it was way to think. Any help?

 

[Richard Coers]

Use a casting resin. It won't just naturally flow inside all the nooks and crannies. Most casters will used a vacuum chamber or pressure vessel to remove bubbles and get the resin deep in the voids and remove air bubbles.

 

[Bill Boehme]

When you mix epoxy the ratio of resin to hardener is critical and if it is off more than about 10% it might not harden. When you mix the two parts there is a strong exothermic chemical reaction (meaning that a lot of heat is released) and if you mix a large batch the heat generated can cause the reaction to become high order (which basically means that the reaction will accelerate and generate enough heat to cause the epoxy to turn dark brown and bubble). Also, If you want the epoxy to penetrate into the wood that isn't going to happen.

If you want something that penetrates into the wood, the lowest cost solution is probably Minwax Wood Hardener. Then you could fill the cube with a plastic casting resin. As Richard mentioned, use a vacuum chamber with Alumilite resin or Inlace resin.

 

[Gary Beasley]

More commonly what Ive seen is the use of a pressure pot with the alumilite to drive the resin into the wood as it sets up. This is commonly referred to as the “worthless wood” process if you want to research it as its been used to take normally unuseable wood with voids and pockets and turn it into beautiful works of art. Not recommended to use polyresin as it will not bond with the wood properly.
As Bill mentioned, a stabilizing step is often used with softer species, oftentimes vacuum stabilization with a product like Cactus Juice from Turntex.

 

[john lucas]

I've used casting resin with success. I have use West System for some fairly thick pours but nothing like you are talking about. Most people seem to be using Alumilite or Cactus Juice and a pressure pot and I've seen spectactular results from those.

 

[Tom Albrecht]

When using a pressure pot and cactus juice, do you have to follow up with heat in an oven? Or, is the heating process something that is only required if you have merely soaked the wood in the juice rather than using vacuum pressure?

 

[Paul Sook]

Thanks for all the responses! Very good information has prompted another question. What if you don’t have a pressure pot? I did coat it very good with epoxy first. Will that matter in choosing a casting resin? And will that help with the air bubbles?

 

[Paul Sook]

Or should I pour it in multiple pours?

 

[Tom Albrecht]

If you have already coated it with epoxy, I would think that your chances of anything else being able to soak into the wood are pretty nil.

 

[Dave Bunge]

I'll second what Bill said about being careful about heat release if you do decide to work with epoxy. The epoxy resins give off considerable heat when they cure. If the heat cannot be dissipated (lost to the surroundings), it raises the temperature of the epoxy. The higher temperature makes it cure even faster, giving off more heat, which raises the temperature further...a classical example of uncontrolled positive feedback, aka runaway chemical reaction.

Here's more info from the West System's website: https://www.westsystem.com/safety/uncontrolled-cure/

The guidance from West is to limit how deep of a layer of epoxy you work with at time. I don't remember the exact number, but it's something like 1" thick. So a 6" cube would be a risky proposition to pour all at once. But would be ok if poured in multiple, thinner layers which are allowed to cure before adding the next one.

West has a pretty good technical staff; contact info is on their website. They could advise on how deep is safe to pour at once, and which products are more suitable for deeper pours.

Dave

 

[Gary Beasley]

When using a pressure pot and cactus juice, do you have to follow up with heat in an oven? Or, is the heating process something that is only required if you have merely soaked the wood in the juice rather than using vacuum pressure?

The cactus juice is used with a vacuum chamber to permeate the wood fully with the resin, and it is cured in a 200F oven for two hours or more depending on the thickness of the wood. After that the alumilite cures like epoxy, two parts mixed and poured. Alumilite is very moisture sensitive so you need to dry the wood very well before pouring or you will have poor results according to what Ive heard from the penturners site I read. They even say high humidity in the air is a problem. Cactus juice will not fill voids so you cant use it for anything but stabilizing the wood.

 

[Bill Boehme]

When using a pressure pot and cactus juice, do you have to follow up with heat in an oven? Or, is the heating process something that is only required if you have merely soaked the wood in the juice rather than using vacuum pressure?

Cactus Juice is used with a vacuum. The piece is submerged in the Cactus Juice in the vacuum chamber and when a vacuum is pulled it draws all of the air out of the wood ... and there is a surprisingly large amount of air in dry wood. When the vacuum is removed atmospheric pressure forces the Cactus Juice into the wood to replace the volume previously occupied by air.

It would be pointless to try to use a pressure chamber to force Cactus Juice into the wood because the compressed air in the wood would force most of the Cactus Juice right back out of the wood as soon as the pressure is removed.

Yes, heat is always required to cure the Cactus Juice ... otherwise, it would stay liquid forever. You can't just "merely soak" wood in Cactus Juice because it wouldn't penetrate into the wood without going through the procedure of using a vacuum to first pull the air out of the wood and then using atmospheric pressure to replace the air with Cactus Juice.

Cactus Juice works best with soft punky wood or wood that is spalted.

 

[Bill Boehme]

Thanks for all the responses! Very good information has prompted another question. What if you don’t have a pressure pot? I did coat it very good with epoxy first. Will that matter in choosing a casting resin? And will that help with the air bubbles?

Here is what I think is the easiest and least expensive solution. I would first soak the piece of wood with Minwax Wood Hardener. It is thinner than water and with multiple applications it can even fill small gaps. After that you could use clear Inlace resin which is actually Reichhold Polylite 32153-00 orthophthalic casting resin. With any casting material make sure not to trap any air pockets as you gradually fill the container. Inlace costs less than epoxy, doesn't have bubbles which is one of the main issues with epoxy, is water clear and doesn't yellow with age.

 

[Robin Thompson]

I use alumilite mixed as close to 50/50 ratio by weight as i can get. I have used a vacuum chamber and a pressure pot. With the vacuum chamber, I made the mistake of making the actual vacuum chamber too big such that before I could remove all the air from the chamber the casting was hard resulting in a failed project. The pressure pot worked better except that the pressure pot just compressed the air bubbles to a smaller size and doesn't remove air from the casting with the end result being a murky casting. The last thing i realized was that to pour multiple thin layers to build up the casting didn't work because each layer failed to bond properly with the preceding layer. I strictly use a pressure pot now and do the pours in one shot. Largest casting was a pencil vase about 9 inches diameter 10" tall.

 

[Tom Albrecht]

Here is what I think is the easiest and least expensive solution. I would first soak the piece of wood with Minwax Wood Hardener. It is thinner than water and with multiple applications it can even fill small gaps. After that you could use clear Inlace resin which is actually Reichhold Polylite 32153-00 orthophthalic casting resin. With any casting material make sure not to trap any air pockets as you gradually fill the container. Inlace costs less than epoxy, doesn't have bubbles which is one of the main issues with epoxy, is water clear and doesn't yellow with age.

You are such a font of knowledge Bill! Have you used the orthophthalic casting resin? Where does one get it?

 

[john lucas]

Tom I have used Clear Inlace. It has pros and cons. It starts to harden fairly quickly so you have to get done what you want very fast. On the plus side, it does harden quickly so you can actually wait until it starts to gel and then push it into cracks all the around the vessel. All other epoxies and resins I've used you have to build a dam to do that sort of thing. The casting resins I've tried you can pour in layers if you want, which is how they cast an ice cube with a fly in the middle. To get things to float you pour in some resin, let it harden to the point it will float whatever you put in, then pour in some more. That was how I got my mini goblets to float in my pregnant goblet piece.

 

[olaf Vogel]

If you have already coated it with epoxy, I would think that your chances of anything else being able to soak into the wood are pretty nil.

That would be my approach.

1 - thin the expiry with alcohol. Warn the wood. Both increase viscosity and improve penetration.
2 - repeat until you’ve filled any deep holes.

Then encase.

I’ve also done thick pours in layers. Wait for the first to set, then add the next layer.
I’m no expert on the amount of thermic reaction, but check out these videos for info

View: https://m.youtube.com/watch?v=xfqY0DTPlVg


That’s a lot of epoxy !

 

[Mike Brazeau]

You can greatly reduce the resin requirement by roughing out the shape of the original wood and then turn from scrap wood pieces that fit the interior and exterior shape and cast all together with resin. After hardening, turn away the scrap wood turn and turn final shape of the piece. Dave Bell is our local guru and demonstrated at the Pittsburgh symposium I believe.

 

[DON FRANK]

When choosing a clear resin for thick pours, either epoxy or urethane, choose one with a fairly long pot life. Pot life is the time it takes for the reaction to happen that begins to cure the resin. Choose one that has twenty or thirty minutes of open time (pot life) and because of that may take 24-48 hrs to cure completely. The slower the reaction the lower the exotherm when dealing with inches of depth.
Curing them in a pressure pot will greatly improve the results as it will drive the resin into all the pits and voids. This longer pot life gives the pressure time to get into all the nooks and crannies. With a pressure pot, more pressure will not yield better results, at least results that you can see. I never run a pot above 65lbs and make sure that by safety relief valves release at 75lbs. A pressure pot is a dangerous tool if handled incorrectly. Google c youtube for pressure pot failures. You do not want to be in a room if a pot fails because of excessive pressure.
You will need to overfill the resin in your container above the height of the wood because the level will drop considerably if your piece has hidden voids. The wood should be dry but epoxies are more tolerant of moisture than urethanes are. Both like room temperature around 70 degrees. Multiple pours can be made but you take the chance of improper bonding and if you are adding any colorant or metallic powders these secondary pours are usually noticeable. Smooth-0n sells a very good casting epoxy and also an excellent crystal cure urethane.

 

[Bill Boehme]

You are such a font of knowledge Bill! Have you used the orthophthalic casting resin? Where does one get it?

Reichhold 32153-00 is an industrial product used to make faux granite and onyx countertops and is only sold in large quantities by the manufacturer. Inlace is the same product that has been repackaged in small quantities by a small business middleman. I have used it quite a bit, both the clear Inlace and Inlace that is premixed with realistic looking plastic turquoise colored granules. I mostly use the clear Inlace now. A couple sources are Craft Supplies and Turtle Feathers.

Inlace has a thin "open time" of 15 to 20 minutes and if you are accustomed to using epoxy you will find that Inlace is significantly thinner. When it begins to gel it gets thick in a New York minute so that is your warning that you need to be wrapping things up. I sort of wait until the first sign of it beginning to thicken and then work like a madman to finish before it is too late. You need to have everything planned and ready to go before you add the initiator to the resin. For a longer open time you can reduce the number of drops of initiator. There is a product called ThickenIt! that can be used to ... duh ... thicken it. However, using ThickenIt! will decrease the clarity slightly. If you are using dyes, metallic flakes, or other stuff then that is not a problem. There is a SystemThree silica product that is the same thing as ThickenIt!

One thing that I learned about storing Inlace is that it will keep for two or three years if stored in a refrigerator and the can is properly sealed. If you store it in a hot garage in the summer the life might be less than six months. I have a garage fridge where I store my CA and Inlace. (BTW, CA will keep five years or more if refrigerated.)

One of the perks of being a senior citizen is having a supply of syringes for insulin or beta interferon injections. If your favorite casting resin doesn't dissolve the plastic syringe then you're good to go. I have glass syringes which are ideal for Inlace.

 

[Tom Cowsert]

Bill, can you add any tints, or colors to Inlace? I have seen some quite nice resin casted blanks of differing colors that create a nice whispy look to them and was wondering of you can do the same with Inlace.

 

[Bill Boehme]

Bill, can you add any tints, or colors to Inlace? I have seen some quite nice resin casted blanks of differing colors that create a nice whispy look to them and was wondering of you can do the same with Inlace.

Inlace sells three kinds of dyes (metallic, pearlescent, and solid) especially made for coloring the resin and they work very well. I haven't tried any other product and I'm not interested in taking chances and messing up a project.

 

[Tom Cowsert]

Inlace sells three kinds of dyes (metallic, pearlescent, and solid) especially made for coloring the resin and they work very well. I haven't tried any other product and I'm not interested in taking chances and messing up a project.

Excellent! Thank you for the response!

 

[Jason Waguespack]

WOW ---- never heard of finishes like this --- all new to me ----- I'll keep following this post. THANKS

 

[Tom Albrecht]

Hello again! Waking up this thread once more. . .

I was just re-reading parts of this thread and I am still learning about Cactus Juice, epoxy, and Inlace.

I have lots of dry burls, mostly cherry. There are some small voids and cracks that need to be filled in order to keep some projects intact.
I understand that Cactus Juice is not appropriate, and I have tried some epoxies like West, but the epoxies are quite runny.

Is Inlace the answer I need? And if so, does it need to be used with "nuggets" or "metal dust"?

 

[john lucas]

Well.inlace is interesting in that it starts to.cure very rapidly. So you can stir in the hardener and when it starts to get thick pour it in.. as it gets thicker as it cures you can actually spread it with a stick. Its wonderful for filling cracks because at first it's quite thin and will.penentrate small holes. When filling large voides you just keep.working with it as it thickens. I've actually filled grooves running around a vessel.while it's on the lathe. You have to work quick.

 

[Bill Boehme]

In addition to what John said, I've made barriers using tape and I have made dams that sit proud of the surface using Minwax Wood Filler. After the Inlace has cured, the wood filler gets turned away. Initially the Inlace is very thin and can seep through tiny gaps in the tape or the wood filler so it takes a bit of learning by failing to figure out when to pour the Inlace. Preplanning is important ... I learned this by not adequately preplanning. I have kept Inlace for several years by keeping it in my garage refrigerator. It is extremely important to clean the lip of the can and the lid. Then make certain that you seal the can well ... no hitting with a hammer because that might dent the seal.

 

[Tom Albrecht]

Thanks Bill
When you say “Minwax wood filler” do you mean the stuff that’s basically Bondo that you mix with a hardener?

 

[Bill Boehme]

Thanks Bill
When you say “Minwax wood filler” do you mean the stuff that’s basically Bondo that you mix with a hardener?

No, it's the stuff like this picture that I buy in a squeeze tube. I think it is also available in a larger tub container.



It is used to patch damaged areas on wood (gouges, dings, nail holes, etc). Once dry it sands and cuts much like wood. It works best if the wood will be painted. They say it is stainable ... if you don't set your expectations too high. It is light tan colored sort of like maple except for being featureless.

Now that you mention Bondo, it might be a better product for this application.

 

[Tom Albrecht]

I originally used the Minwax two part filler wood filler until I figured out that it's the same as Bondo. I used it so much on some of my early architectural spindle turnings that I was called "Bondo Boy" in the millwork shop. It does set up pretty quickly and can patch deep errors, like when the skew isn't presented properly and it takes off down the bead leaving a spiral trench in a piece that otherwise was perfect and already took 35 minutes to turn--- only used for painted work. It too, will set up in the grain and need to be dealt with in anything that's not for paint.

 

[Tom Albrecht]

I had my first attempt using Inlace an hour ago, we'll see.

My first impression with using thickener is that in needs a lot to make a difference in the consistency--- is that right?

Do keep both parts in the frig?

 

[Bill Boehme]

I had my first attempt using Inlace an hour ago, we'll see.

My first impression with using thickener is that in needs a lot to make a difference in the consistency--- is that right?

Do keep both parts in the frig?

I have thickener, but have never used it because it will make the Inlace cloudy. I usually stir in the catalyst and then let it sit for a while, I periodically stir it a bit to tell when it is just beginning to tighten up. That is the two minute warning to work quickly when I quickly apply it to the wood.

 

[Gerald Lawrence]

Yes it does take what seems like a lot of that powder to thicken it. I have only used it a couple of times. I suggest only use if you have to put it in all the way around the turning, that is it is one or more lines around the turning.

 

[Don C Davis]

For a project like you described Alumalite is the perfect answer IMO--I have made several pieces like you described-I actually make a lot of pieces using specific size molding 'tanks' I made from HPDE. I also use a lot of Cactus Juice for stabilizing pen blanks--I really like various burled woods and lots of these pieces come very punky and soft--Cactus Juice works great--I actually get excited when I pull the aluminum wrapped pack out of the toaster oven--and get to unwrap the pieces! Working with Alumalite is pretty simple and straightforward IMO--I've used both vacuum and pressure and pressure has provided better more consistent results for me.
Good Luck with your project!!

 

[Brad Winesett]

I would like to use the clear Inlace on a few bowls with small voids. I do want to add color to the Inlace, but you have to buy the colored dyes individually, and they are fairly pricey. Is there anyone that sells a color assortment of dyes at a decent price that is compatible with Inlace? I'd like to spend $20 or $30 on assortment that would come with a small quantity of 5 or 6 different colored dyes.

 

[Bill Boehme]

I would like to use the clear Inlace on a few bowls with small voids. I do want to add color to the Inlace, but you have to buy the colored dyes individually, and they are fairly pricey. Is there anyone that sells a color assortment of dyes at a decent price that is compatible with Inlace? I'd like to spend $20 or $30 on assortment that would come with a small quantity of 5 or 6 different colored dyes.

I have a number of Inlace dyes and I would be very hesitant to save a few dollars by using something else based on a lower price. The regular dyes are $10.50 and they are concentrated so you do not need much. The Inlace dyes maintain clarity. There are also pearlescent and metallic dyes which cost about $17. I haven't used them so I can't comment. Other dyes might make the Inlace cloudy or even prevent it from hardening.

 

[john lucas]

I use a lot of Trans Tint dyes in epoxy but you really don't save much money because they are also expensive. Only takes a few drops however so they go a long way and the color is archival.

 

[Dean]

About cactus juice, it should be used in a vacuum chamber. Alumilite casting resin should be used in a pressure pot. For worthless wood, infuse the wood with cactus juice first. Then build a mold and use Alumilite to complete the turning block. Both Cactus Juice and Alumilite take dies so the variations are infinite. The cactus juice will keep the casting resin from coloring the wood. If you do this the way described above you will get very clean lines between the wood and resin.
Turn tex makes dies to augment the alumilite colors so you can come up with all kinds of colors.
Hint: make sure you record each mixed color when you make it, this way you can replicate it down the road if you want or more importantly if someone else wants some piece the same color.

I do not know nothing about inlace