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Epoxy Use for Repair Work: Advice on Technique

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Forum topic by Lovegasoline posted 10-19-2020 11:19 PM 627 views 0 times favorited 20 replies Add to Favorites Watch
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Lovegasoline

176 posts in 950 days


10-19-2020 11:19 PM

Hello All,
This concerns repairing kitchen cabinet doors with West System 105 epoxy, #207 hardener, and #407 filler.
I’ve little experience with epoxy (other than a handful of 5-minute epoxy repairs) so any suggestions, tips, or observations will be welcomed.

These are very old doors that had endless layers of paint and were in very sad shape. They are poplar paint grade doors and will be finished with a primer followed by a white urethane base top coat.

————-
Proviso:
Due to this project having been entered into with knowledge aforethought of the high degree of personal challenge demanded – along with elements of masochism -please kindly refrain from posting the following content as it will only serve to derail the thread:
a.) red flags regarding chemistry safety, stripper safety, scraping safety, lead paint, etc. etc. as those areas are extremely well researched, understood, and implemented. Period.
b.) well intentioned advice to abandon this work and replace the doors. These doors will be repaired and put back into service. Period.

————-

They’ve been mostly stripped already. Peel Away 1 was initially used on a couple doors which worked well, maybe too well as it damaged the veneer of a couple door panels. After that it was discontinued and replaced with methylene chloride, much less effective and slower. At this stage the majority of paint has been stripped. Several doors need additional work on the molding profiles which still hold paint to one degree or another and that’s just a matter of tedium with repeated applications of stripper.

On to the repairs.

Pics
The first three pics show the doors with the most damage.
Pic#1 shows some of the large panel splits and how the veneer has curled open at these areas.
The last three pics show close ups of this type of defect after some scraping.
Pic #2 shows the interior panel side of one cabinet door with dozens of small checks. The checks are not that deep and it’s not a show surface, so can be easily surfaced and of minor concern. It also shows what looks to be gaps in the glue joint.
Pic #3 shows a crazy chunk missing from one door. Other areas like this on other doors were filled with Bondo but remaining big missing chunks will likely get epoxy + filler.

The doors all appear solid and structurally sound. None have declared any indication of wanting to come apart. There were so many – dozens – of paint layers that initially one thought was it was the paint holding them together, lol.

Panel Veneer Repair:
Two doors have sustained damage to the panel’s veneers as mentioned. The stripper seems to have introduced numerous splits and checks into the surface of the veneered panels and may have attacked some of the glue of the panel’s ply [see pics]. Due to the surface tension many of these splits/checks have also curled a little at their openings like ‘lips’ similar to deep knife lacerations or entry wounds on the skin. After a quick sanding I’ve started to use a scraper to remove high spots and level the panel surfaces.

The plan is to complete the scraping and then repair and level the panels with epoxy. One suggestion was to use a hypodermic needle or syringe to shoot some epoxy into and under the open checks/splits. That sounds like a good idea.

Question: Is it advisable to thin down the epoxy so it can flow into the spilts/checks and help consolidate and bind to the inner layers of ply?

Afterward injecting epoxy into the splits, as a foundation a (thinned?) layer of epoxy will be rolled on so it can coat and consolidate the entire panel surface and seep into the checks and splits. That will follow with a fairing layer: a troweled on layer of epoxy thickened with the #407 fairing filler (which is supposed to be easy to sand and level) to fill any gaps/checks/splits and to even the surface out. When dry and sanded it will hopefully resemble a more or less planar panel.

The remaining repairs are more straightforward gap/chunk filling operations so will get patched with some epoxy + filler.
Finally, in a couple areas where the glue may possibly have been attacked on the rail/stile joints so epoxy will be flowed into any gaps in the joints to fortify them.

Suggestions?

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps


20 replies so far

View Aj2's profile

Aj2

3491 posts in 2709 days


#1 posted 10-19-2020 11:44 PM

I just don’t see how epoxy is going to fix anything. Epoxy is expensive and messy.
If you don’t want to make new doors there’s plenty of online companies that will make them for short money. http://www.dreeswoodproducts.com/
Wasn’t I on your block list? It’s kinda rude to tell a open forum what not to talk about.
Good luck always

-- Aj

View SMP's profile

SMP

2852 posts in 817 days


#2 posted 10-20-2020 12:12 AM

I’d personally probably use bondo on those TBH. Its a-lot easier to sand etc. And I used to do fiberglass work professionally.

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#3 posted 10-20-2020 12:24 AM



I’d personally probably use bondo on those TBH. Its a-lot easier to sand etc. And I used to do fiberglass work professionally.

- SMP

Thanks for your opinion SMP.

As mentioned I used Bondo for some of the larger gaps (like in the the 3rd pic) and I also used it for repairs to the built in cabinet framing in the kitchen. It’s held up well so far.

Others had suggested that epoxy (at lower viscosity) can be flowed into the splits/checks and help bond the outer ply to the substrate where it had delaminated. Bondo is way too viscous to perform in that manner in my experience.

Also, the suggestion was that epoxy with fairing filler would sand easier than Bondo, which would be tougher. But as mentioned I’ve never sanded epoxy or used it to any extent other than the 5-minute types to do small repairs

If nothing else this project seems to have presented an opportunity to experiment and get acquainted with epoxy.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

View SMP's profile

SMP

2852 posts in 817 days


#4 posted 10-20-2020 12:47 AM

True, good learning opportunity. Just make sure you have a good respirator and work in a well ventilated area. Half the time I did fiberglass/epoxy work was INSIDE of cars so i didn’t have a choice a lot of times. But I did always wear a 3M cartridge style respirator. The stuff is real nasty to breathe in.

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#5 posted 10-20-2020 12:50 AM


I just don’t see how epoxy is going to fix anything. Epoxy is expensive and messy.
If you don’t want to make new doors there’s plenty of online companies that will make them for short money. http://www.dreeswoodproducts.com/
Wasn’t I on your block list? It’s kinda rude to tell a open forum what not to talk about.
Good luck always

—Aj

I can’t imagine epoxy can compete with messes I’ve already made.

Here’s the kind of mess that inspires me. Soupy oozing lye flung floor to ceiling in …

You’re likely thinking of someone else Aj as I don’t have a block list.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#6 posted 10-20-2020 01:17 AM



True, good learning opportunity. Just make sure you have a good respirator and work in a well ventilated area. Half the time I did fiberglass/epoxy work was INSIDE of cars so i didn’t have a choice a lot of times. But I did always wear a 3M cartridge style respirator. The stuff is real nasty to breathe in.

- SMP

Sometimes it seems I practically live in a respirator. I use it for everything. That said, it’s the very lowest item on my respiratory safety totem pole.

No fiberglass will be used … however … I have some small plywood wedges (like shims) to aid heavy stuff on casters to easily roll up and over raised thresholds. The plywood tapers to a point which could be fragile and crack apart over time. There’s some unused woven fiberglass that’s been taking up space forever so I plan to experiment with it and do a quick & dirty epoxy/fiberglass layup on the plywood wedges. Those are utility items so won’t be sanded and should satisfy my curiosity regarding fiberglass.

Back to the doors the West Systems 407 filler is reputed to have been formulated to sand and shape easily.

If I was working inside confined enclosed spaces I’d want to have a supplied air system in addition to respirator. I like the idea of both belt and suspenders when it comes to the respiratory system. I’ve learned those lessons the hard way.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

View Chenier's profile

Chenier

25 posts in 618 days


#7 posted 10-20-2020 01:42 AM

Well, if you want to get acquainted with epoxy … :p

Disclaimer: I haven’t done this kind of repair, but I’ve built a couple of small stitch & glue boats with epoxy so I know enough to be dangerous.

First things first: Low viscosity epoxy is lousy glue because it has no gap-filling properties. When you’re gluing things together with this kind of epoxy, when you’re building up structure such as fillets, or when you’re simply filling anything larger than a pinhole you want or need to use some kind of filler. There are several, each with different applications:

- Wood flour is used for fillets or big holes, like pic #3. For building fillets you add enough wood flour to make the mix peanut-butter like and you can trowel it on. For pic #3 I’d make it more runny so you can pour it down the hole.

- Colloidal silicon is used as a thickener when you’re trying to make epoxy glue. You want a consistency about like French’s mustard. This has been used for decades, but it has two significant downsides: First, colloidal silicon is the stuff that gives you silicosis, so you must wear a good respirator mask while mixing. Second, silicon is the primary ingredient in sand. After the epoxy has hardened you have to take a grinder to it if you want to do any further shaping or smoothing.

- Colloidal cellulose is relatively new. It does the same thing as colloidal silicon, but you don’t need a respirator and you can use your conventional shop tools on it. I don’t think WEST markets a version yet, but MAS does.

- Phenolic microballoons are simply fillers for fairing. They fill nicely at a lot higher price than wood flour, but give a smoother surface before sanding. Since they’re little balloons they’re lighter than anything else, but also weaken the epoxy matrix. Good for surface coats but nothing structural.

My thoughts:

Where the veneer has peeled up, inject some epoxy w/ colloidal cellulose under it. Don’t simply depend on flow. WEST and others sell syringes (without needles) that can be used for the purpose. Then cover it with Saran-wrap (or equivalent), a flat piece of wood, and a weight that will press it all down flat.

Where you have checking, like pics #4 and #5, microballoons or any other fairing filler would do fine.

A couple of hints:

- After you apply your epoxy it’s worthwhile to get it as smooth as possible before it starts to harden. And clean up any “oops”. That will save you some hard sanding after it’s hardened.

- Epoxy hardener is hyperallergenic. Get enough on you and you can become severely allergic to the stuff. Be meticulous about gloving up and keeping mixed epoxy off you. Also: after a day the epoxy seems hard and can be sanded and worked. But it takes about seven days to fully cure and during that time the hardener is still active. If you’re sanding etc. before those seven days are up, wear a respirator.

- Epoxy is permanent. Never try something for the first time ever on what’s going to be your finished piece. Make some test mock-ups and try it out on them. If you screw up it won’t last a lifetime.

Finally:

https://www.westsystem.com/instruction-manuals/

You might be interested in the “Other Uses” manual which includes a lot of home repair.

Good luck!

View Aj2's profile

Aj2

3491 posts in 2709 days


#8 posted 10-20-2020 03:50 AM

Yep that’s a mess. Your right I don’t see how you can make it any worse.
Back to the doors they are in poor condition. If you can somehow save them my hats off to you.

I checked the blocked list it’s some other pilgrims that have me blocked.

Good Luck with your project

-- Aj

View PCDub's profile

PCDub

226 posts in 1155 days


#9 posted 10-21-2020 02:08 PM

West Systems has a technical advice toll-free phone line and they would be happy to help you out with determining which of their products will work the best for your various issues.

866-937-8797, Monday to Friday, 9:00 am to 5:00 pm ET

View CaptainKlutz's profile (online now)

CaptainKlutz

3825 posts in 2406 days


#10 posted 10-21-2020 03:12 PM

+1 West systems publications and hot line for best help source.

+1 Avoid Colloidal silicon unless you are anal about safety. The stuff looks like barbed thorn rose branches under microscope and it never leaves your lungs; once it enters. Raw or the sanding dust is dangerous. Effects are cumulative over your lifetime. Silicosis disease creates manageable COPD symptoms in the best case, and death via lung disease (like coal/asbestos miners) as worst case. Suffocating due poor safety from epoxy filler is horrible way to die.

Suggest phenolic micro-balloons or wood sanding dust is much better choice. Heavy concentrations of wood dust and fibers in an epoxy putty will allow the surface to accept some stain or paint. Will not absorb much, but generally enough that it looks like grain variation, and provides better adhesion for paint.

Cured epoxy has tendency to surface blush with excess curatives. It is also cross linked and not chemically active. The combination of these two defy paint to adhere to surfaces. Will need to rough sand epoxy with 80-100 grit to remove the blush, and create teeth for paint to achieve a mechanical bond to epoxy.

Best Luck!

-- If it wasn't for bad luck, I wouldn't have no luck at all, - Albert King - Born Under a Bad Sign released 1967

View drsurfrat's profile

drsurfrat

204 posts in 98 days


#11 posted 10-21-2020 09:23 PM

Can you use superglue/cyanoacrylate with a pointy tip applicator to hold down the “lips” that are curling up? Then rolling on epoxy would bond anything that you thought was too brittle or delicate from the CA.

I used West System epoxy a while ago, and it worked well. I was warned that pre-thinning with alcohol was a bad thing, it interferes with the molecular bonding (google “epoxide ring opening”) so that you won’t get the correct crosslinking.

You said you looked forward to experimenting: I did manage to use it on a small piece (wood cup finished to 320 grit). AFTER it started to set, but not fully firm, I scrubbed the surface with isopropyl alcohol. It left a surface that seemed like bare wood, but water beaded up on it. It was very cool. I think it was a 30 min set mixture so there was time to soak in, and to catch it at the tacky-firm point.

-- Mike (near Boston) ... Laziness is the mother of invention, necessity is the mother of exhaustion - me

View WoodenDreams's profile

WoodenDreams

1177 posts in 822 days


#12 posted 10-22-2020 02:36 AM

With the shape of the panels. Wouldn’t it be quicker to just make another door. If I had the materials on hand, the one cabinet door would be made the same day. Day two would be for match staining, Day three would be for applying finish coats.

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#13 posted 10-22-2020 11:41 PM

Chenier,
Thanks for the tips and taking the time to write that.

I did forget to mention I have a bag of wood flour (fines from dust bag) that I was intending to use for big gap filler.
I have the West Systems manual and have been perusing it.

I forgot to mention I was planning on using CA glue first (I’ve got various viscosities), injected into the splits to aid in securing the laminations. After that, a thin layer of thin (or just straight?) epoxy as a base to soak into the wood for the thicker filler layer(s) to adhere to. Then thicker filler/fairing layers.

I didn’t realize it needs some form of filler for epoxy to act as a glue rather than using it straight. Straight epoxy is a no go for ex. gluing an edge joint with two jointed boards ?

Good to know the cure time and sanding issues (maybe I’ll just let it cure before doing any sanding), colloidal silicon issues (I’ve handled fumed silicon before occasionally with great respect, thought I avoid it as much as possible), and Colloidal cellulose … I’ll look into the latter. As an alternate application, I do have some areas on interior doors around locks/mortises (old building) that need some repair work and it looks like a good use for epoxy (maybe with wood flour or the colloidal silicon).

I also came upon the technique of a toothed applicator for applying the initial fairing layer, then after it’s dry sanding is easier as just the high spots will be removed until it’s leveled to where I need it, followed by another application to fill in the grooves left by the teeth, and a final sanding.

Saran wrap use is also good to know.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#14 posted 10-22-2020 11:42 PM



Yep that’s a mess. Your right I don’t see how you can make it any worse.
Back to the doors they are in poor condition. If you can somehow save them my hats off to you.

I checked the blocked list it’s some other pilgrims that have me blocked.

Good Luck with your project

- Aj2

Thanks Aj2.
That’s an old mess but it’s where the cabinet doors will go.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

View Lovegasoline's profile

Lovegasoline

176 posts in 950 days


#15 posted 10-22-2020 11:44 PM



West Systems has a technical advice toll-free phone line and they would be happy to help you out with determining which of their products will work the best for your various issues.

866-937-8797, Monday to Friday, 9:00 am to 5:00 pm ET

- PCDub

I had called that prior to moving forward. The rec was to use the 207 hardener as it wouldn’t need to be washed after curing, and the 407 filler would make sanding easy.

-- “It is the beginning of wisdom to recognize that most men are fools and knaves, but it is the end of wisdom to embrace that vision.” -Arthur Kleps

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