what's happening here?

[Chris Townley]

HI I am working on my truck bed.
It is red oak.'In prep I sanded it down with 220 grit.
then right before I got ready to put the finish on I wiped it down with some acetone and let it set about 30 minutes before putting on epoxy
I am using totalboat 2:1 penetrating epoxy.
When I mixed it I followed the directions perfectly. I applied it in a garage and kept the doors closed so no dust would blow up.
I used a brush to apply the material on some of the boards; and later changed to one of those foam brushes.
I got the same result with both methods.
My issue is it has little 'bumps' all over the boards. I had hopes it would all blend together. Didn't happen.
The boards have been drying four days. I knew I needed to sand the surface before I apply a second coat.
But my question is this. What caused these little bumps all over the wood. They showed from the moment I brushed the material on. Like I said I had hoped it would level out?
How do I proceed from here. I want a nice smooth slick glossy finish when I get done; but right now since I don't know what happened I am at a loss how to proceed correctly.
I'll attach a picture so you can see it and give me your thoughts.
You can see the little 'dots' in the picture. I can sand them down where you don't feel them; but they still are visable.
As I add more coats will they disappear or the problem just keep getting worse.

20190305_125653.jpg
A couple things I can toss out I did not do wrong (according to instructions)
It was clean wood; wiped free of all dust and no dust in the garage. I mixed up the epoxy as directed and mixed for the proper amount of time. No bubbles were present in the mixing cup.
So help me out so this project will turn out as hoped
THANKS

[Allan Dozier]

Are they bumps or craters? If they are bubbles then it is air escaping from the pores of the oak. Best way to get rid of them when they appear is to flame them with a propane torch (quickly and carefully). Best way to minimize their formation is to apply the epoxy in the evening when the temperature in the room will be dropping over the next few hours.
However, it they formed immediately when brushed on and they are definitely bumps of material then I don't know but seems like some loose material that was still in the pores. Did you vacuum it or jut wipe it with acetone?

[Chris Townley]

HI thanks for the reply.
They are bumps. I was curious if I put the material on "too" thin. I read maybe air is escaping from the wood as it cures??
The wood came from a furniture factory where it was cut then kiln dried. It's been in temperature controlled storage ever since.
As far as prep - I sanded it with 220 to get it smooth; them I blew off all the dust with air. Blew out the garage and let everything set over night.
Before I started to apply the epoxy I wiped down the boards with acetone and let them set about 1/2 an hour before starting. I even wore gloves when I applied the material so I wouldn't get oils from my skin on the wood.

I'm worried I'll have to sand it down and start all over again;... but then again I don't know anything different to do when I do it again...
I did start about 2 pm on the first pieces and was done about 7 pm; of course then night fell and the temps fell a little - never below 60* tho.
So I'm at a total loss....
I will say there are places are very smooth; but those are places I thought I had too much when I put it on.
OH and in the grain there are some places that look like they didn't take any material at all (like it was a hard grain and did not absorb any material)
SO can I sand the bumps off and if I add another coat will they still show through?... or get more bumps next coat>??

[Scott Winners]

Instead of sanding drudgery, you might consider scraping with the grain using a paint scraper with a clean sharp blade and smoothing that way. Then sand the pretty flat surface before recoating.

I have never applied epoxy to red oak, haven't been contributing to your threads. I have only used West system epoxy. With that family of products there is a recoat without sanding window, and then after that window I have to sand before applying the next coat.

[Donald Cole]

Looks like 'Fisheyes' , which are caused by silicone, oil or other junk on the wood. You can buy fisheye eliminator at Auto body supply stores to add to the epoxy.

[Allan Dozier]

"I will say there are places are very smooth; but those are places I thought I had too much when I put it on."

This part sounds encouraging. It may have been that the wood was just not as smooth as you hoped when applied. Red oak is pretty porous. I bet after you sand the first coat smooth, the second will be smooth and solid. West epoxy does blush when cured so wash the blush off. Some have recommended ammonia for this but I have used different different things as long as it is cleaned. Then sand, clean well and apply the next layer.

If you have a lot of West System left then use it but if you need more epoxy I will put in a plug for MAS. They make a version that is the clearest and lowest viscosity epoxy I have found. It self levels better and also does not blush. I've used West and Raka, but MAS is my favorite.

[Chris Townley]

Looks like 'Fisheyes' , which are caused by silicone, oil or other junk on the wood. You can buy fisheye eliminator at Auto body supply stores to add to the epoxy.

Thanks - I'll check into that.
So if it is fish eye; do I have to totally sand it off and start over. I do plan on sanding it down smooth.
I was curious of the next coat would hide the fisheyes from the first coat....
I also plan to put about four coats of varnish over the epoxy - if I had varnish with an amber tint would it maybe hide it?

Obviously I want to do this so it looks good; but hate to do a lot of unnecessary work if one coat will hide the previous.
Would a thicker coat help avoid the fisheyes - I suppose not if it is some sort of element on the wood.
I'm not sure exactly what could be on it. As I said before; the wood was cut; kiln dried; run through a plane just before sanding to make it flat and square.
Only other thing I did was sand it; and then blew the dust off with air from my air compressor. The air goes through two filters so there "shouldn't" be any water in it??
And finally wiped it down with acetone before coating. Any idea of what it might be?? No doubt I have to know what is causing it. If I do the same thing as before I kind of think I'll get the same result.

This epoxy finish is new to me so I am open for suggestions.
THANKS

[Wayne Lomman]

Firstly, the product you are using is a penetrating epoxy. This means it is meant to soak into the timber so as to better preserve it. It is not intended to be a one-coat bar top finish. Rather, it is a primer that protects and preserves before you top coat. Penetrating epoxy will always leave the surface in need of sanding before proceeding to the next coat. It is a bit much to expect otherwise. As I said, it is not a bar top finish you are using and that is a very good decision by the way.

So far you have not done anything wrong. In fact the job is going exactly how it should. You don't have any problems with air trapped in the grain. That is definite pin-hole craters and none of them are visible. You don't have blushing or amine bloom, otherwise you would be asking about the job turning white and/or greasy.

Your next step is to sand it flat and see if the grain is filled as much as you would like. If it is, good. If it is still a bit open, apply another coat of epoxy. Sand it flat again and then start applying your top coat clear. You only need to apply enough top coat to get the gloss you want. Do it in the least coats possible. The timber is protected by the epoxy. All the top coat has to do is give it the necessary shine.

Sanding is unavoidable with a job like this. You can treat it as drudgery as some others seem to do but it is better to accept the fact that it is necessary and set yourself up with some music, beer or just have some thinking time and the job passes quickly enough.

Your preparation was good enough to avoid fish-eyes. These are caused by some form of surface contamination stopping the coating from flowing to that spot. The usual culprits are silicone or oil. Since it is your first coat, the visible dry spots should cover. Don't worry about stain or anything to cover stuff. There is nothing to cover. It all looks OK.

Just to repeat, the job looks like it is progressing as it should. There is no cause for panic. It may take a bit more time than you originally planned but it is going to work. Cheers

[Tom M King]

Just the action of stirring during mixing is going to put some bubbles in epoxy. I use a heat gun passed over it, and you will see the bubbles rise to the top. I've never used a torch, as stated earlier, but I'm sure that would work too.

Back when I had a boat business, and was set up to do fiberglass work, I used epoxy for some things too. A client came in asking if I could make an epoxy and glass tube of a certain size that they could turn on a lathe for some special purpose (I forget what it was for). The stipulation was that it couldn't have any bubbles in it, even small ones. I forget the reason why, but I gave it a couple of tries, squeezing it hard as I wrapped it around a cardboard tube, and used a heat gun. It looked like it didn't have any bubbles in it, but didn't end up working for what they wanted it for because it had too many bubbles in it.

More recently, I cast some close to the ground replacement window sills out of concrete, using old wood for the forms to get the texture. They needed to be painted, but I knew that wouldn't last long directly on the concrete, so I coated them with epoxy as a primer. I thought the bubbles never would stop coming up with the heat gun, and kept pulling the gun off so it wouldn't kick so fast. Bubbles never did stop, but I left it at some stage, and with a light sanding, the coats of paint looked fine.

[Chris Townley]

THANKS to both Wayne and Tom.
I kind of knew this epoxy / varnish finish would be a time consuming process. So I'm not disappointed when you tell me it's going to take some time, and to not rush it.
The truck is a few months away (at least) from being finished; and I plan on running all the wires, brake lines, etc - and then putting on the bed itself; before finally laying in the boards (permanently) and chrome strips after that.

So if it takes me a couple months to get it done; that's OK by me.
I'm really just concerned about doing something "wrong" or having it come out and look bad and then have to redo things over and over. That I really don't have the patience for LOL

I think I read somewhere to sand the epoxy down with (80 grit maybe)..?? Of course you can read anything; but I put my bet on your folks that have worked with boats and used this process effectively. I figure no sense in 'reinventing the wheel" when I have guys that have expertise and know the proper way to go about this. So if this sounds wrong let me know.

Right now I am thinking of just sanding all the board down so they feel smooth without any dimples sticking up. I can see from what little I have sanded so far; this is some TOUGH stuff. Guess that's a good thing as far as protection.
I am guessing after that I can apply the second epoxy coat and see how that looks. IT might be a good idea to turn the boards over and do the BOTTOMS while I am in the learning process here?

I like the idea Tom threw out about using a heat gun to draw out bubbles. I been needing to purchase a heat gun any way so if it helps at all in this process; that sounds like a good thing?
Donald had said I could purchase "fish eye eliminator" to add to the epoxy. I only have a little over 1/2 gallon of epoxy; so even if I decided to do that; I assume it wouldn't take much and that it shouldn't cost much (???) and could make it a little better..?? Outside my field of knowledge here....

I asked a guy at Jamestown Distributers and he recommended I "washed the coat with water to remove any possible amine blush (a waxy by product of epoxy curing), then sand smooth, clean with acetone" and then recoat. I'm not opposed to doing any of these things if it could help the finished product look great. I'm going for a "show truck" look when I get finished; so a little extra effort I am not opposed to.

I REALLY appreciate all the input from you folks. It's nice to have folks share their knowledge to help a project come out right.
Feel free to add anything else

[Dan Hall]

I wonder if it's runout in the red oak and the drying process is siphoning air out of the "straws" that comprise the grain.

If you put a strip of Red Oak, say 3/4"x 1 1/4" into a glass with an inch or so of water in it, over night the wood will be wet from end to end. Do that with ash or maple and only the end will be wet. Just wondering. I don't know much about this stuff but I did hear about that characteristic of Red Oak.

[Wayne Lomman]

Dan, you are thinking in the right direction. The key to understanding this is that Chris is using a penetrating epoxy which is meant to easily work its way into the grain.

Chris, it's necessary to coat your boards all over so if the back isn't done yet, get onto it as you don't want the boards to dry out on one side or they will cup a bit. Do your sanding with 180. Anything coarser will remove too much coating. It's b.... y hard work but the result is worth it. Wash down in case of amine bloom but don't do it until your boards are coated all over. Any chance of a photo of the truck when it's done? Cheers

[Chris Townley]

Dan, you are thinking in the right direction. The key to understanding this is that Chris is using a penetrating epoxy which is meant to easily work its way into the grain.

Chris, it's necessary to coat your boards all over so if the back isn't done yet, get onto it as you don't want the boards to dry out on one side or they will cup a bit. Do your sanding with 180. Anything coarser will remove too much coating. It's b.... y hard work but the result is worth it. Wash down in case of amine bloom but don't do it until your boards are coated all over. Any chance of a photo of the truck when it's done? Cheers

That makes sense. I can do the backs of the boards next and help prevent any cupping issues. Thanks for that suggestion.
I'll use a finer paper. Like you said I know it'll take longer; but the final outcome is what matters.
I'll be happy to post some pics when I get done.
Appreciate everyone's input
Have a great day

[Allan Dozier]

Glad to hear Chris. I thought they looked like craters to me too hence my question. You probably know this talking to Jamestown but you should coat the epoxy with an exterior finish since UV light will degrade the epoxy over time. Since it is a truck and will be used outside. Any number of finishes will work such as exterior varnish or Bristol Finish.

[Chris Townley]

Thanks
I plan on using two coats of epoxy; and then cover with a couple coats of varnish.
I'm giving it four or five days between coats for the epoxy -- sand with some 180 and recoat.