# Epoxy Over Mineral Oil



## Draconei (Feb 7, 2019)

I just finished turning out a segmented mug and got carried away in applying butcher block oil. I typically apply oil to the outside then apply an epoxy to the inside but on this one my brain shut down for a good 5 minutes and I rubbed some of the butcher block oil on the inside of the mug! I’ve already parted the mug off the tenon and the walls are pretty thin so I don’t think I could remount and further turn out the inside.

I've let it sit for a few days now and it seems relatively dry on the inside, but I'm not certain that there wouldn't be problems with the epoxy curing over the oil finish. Any suggestions on how to clean out the oil so I can apply the epoxy (or do you think I could get away not cleaning out the oil and just applying epoxy over it?) I intend to scrub the inside with some denatured alcohol in an attempt to remove sanding dust from pores (compressed air & tack cloth didn't get all of it), would that be enough to clean the oil and help the epoxy bond and cure properly?


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## Steve Neul (Sep 2, 2011)

It would probably be best to never try to put epoxy on the inside. If you must, strip it a couple of times with citristrip paint and varnish remover, rinsing it with soap and water. Any kind of oil will screw with the adhesion of the epoxy and the acidic solvents in the citristrip should break down the oil.


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## Draconei (Feb 7, 2019)

Not what I was hoping to hear! Alas.. This was intended to be a gift to someone who would really USE it and not just set it on a shelf - often with an alcoholic beverage. I've seen many people recommending the use of a combination of beeswax & mineral oil when discussing vessels like this, would alcohol be detrimental to the finish?


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## 35015 (Nov 24, 2012)

Draconei said:


> Not what I was hoping to hear! Alas.. This was intended to be a gift to someone who would really USE it and not just set it on a shelf - often with an alcoholic beverage. I've seen many people recommending the use of a combination of beeswax & mineral oil when discussing vessels like this, would alcohol be detrimental to the finish?


Hi Draconei,

If you are really bent on using epoxies on your woodworking, I would contact the folks at Ecopoxy and ask there recommendations for removing the mineral oil. I know it can be done, but can't remember what I was told the procedure was...I do believe it was Acetone, but by what procedural method I can't remember.

They make some the safest and best food grade epoxies currently on the market and I use them in my work with aquarium/vivarium...

I really love the turning you are doing, and if I may offer an alternative approach to consider (reject please if not to your taste or style...???) have you thought about just treating your wood turned vessels as they had been for millenia?

I have drank out of mugs, pitchers, flasks and the like from the Middle East to Japan, as well as the ones I teach students to carve traditionally in the field during ILS classes. Wood drinking containers have been with us for a very long time (some still in service after 100 plus years!!!) and they never get anything more than the lipids (fats/oils) that are naturally found in the food we consumer or they may get a seasonal dash of beeswax, which is really good for them.

I know some turners "boil in oil" of a food grade type like flax, or better yet walnut and allow to dry. Brian T. (a member here) does a similar procedure in an oven...and the out come I have now seen is excellent!!! Which isn't much different than the "boil in oil" method for the most part...

Food for thought...???...Use what you wish...

j


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## Draconei (Feb 7, 2019)

Thanks very much for the suggestions, Jay! I've only recently begun turning mugs so I'm by no means set in my ways (yet). I've always been told to be leery of fats as they tend to go rancid when used to seal - any thoughts there? As my skill at turning has progressed I've gotten to the point where I can get my walls pretty thin (who wants to carry around a log) so I like using epoxy not just for sealing but also resilience to drops. Do you have any recommendations in regard to that?


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## Steve Neul (Sep 2, 2011)

Personally if I were going to use epoxy in the inside I would do the whole thing in epoxy. Right at the rim where it makes the transition from mineral oil to epoxy would be prone to letting water get under the epoxy. This in itself causes the wood to expand and contract more than normal and would put enough stress on the hard epoxy to cause it to fail prematurely. Sealing the wood overall with epoxy would make it waterproof. It wouldn't have to be the thick poured on look normally associated with epoxy but enough to seal the fibers of the wood.


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## 35015 (Nov 24, 2012)

Draconei said:


> ...Thanks very much for the suggestions, Jay!


Hey Draco!...You are most welcome!



Draconei said:


> ... I've only recently begun turning mugs so I'm by no means set in my ways (yet)...As my skill at turning has progressed I've gotten to the point where I can get my walls pretty thin (who wants to carry around a log)


Well then...color me impressed! I wouldn't have guessed that. Fine work and you do get your wall nicely thinned!!!



Draconei said:


> ...I've always been told to be leery of fats as they tend to go rancid when used to seal - any thoughts there?


Way more hype and nonsense than actual facts about lipids, there chemistry and what happens with proper polymerization with any of them over time...went understood and work properly...!!!



Draconei said:


> ...so I like using epoxy not just for sealing but also resilience to drops. Do you have any recommendations in regard to that?


If you want to stay with epoxy, then I would call and talk to the fine folks at Ecopoxy and ask there recommendations (if any...they may not recommend it for direct long term food contact and hot beverages...???). They will most likely, if recommended at all, suggest a more flexible form of it and a complete covering of several coats inside and a breathable finish of oil/rosin/wax for the outside...or...a pressure impregnation of resin into the wood which essentially makes it "plastic" with wood cell structural matrix...Personally, not my reason to do woodworking...but it has its place...

*Please note, epoxy, in virtually all its applications, is not actually "water proof"...at all!!!...It actually can very much trap moisture inside the wood big time!!!* Epoxies have to be in a very special application blend, layered and worked very differently than most do with it to be actually..."water proof!"

However, from a culinary perspective of long term use, durability, aesthetics, food/beverage taste, and (frankly) traditional sensibilities for a fine piece of turning, they will last longer with a traditional approach modality...I can expand on that if you are interested?

Good Luck,

j


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## Draconei (Feb 7, 2019)

Jay C. White Cloud said:


> Way more hype and nonsense than actual facts about lipids, there chemistry and what happens with proper polymerization with any of them over time...went understood and work properly...!!!


Probably the way there is too much hype over using FDA "food safe" epoxies. Once fully cured, every brand is inert.



Jay C. White Cloud said:


> ...a pressure impregnation of resin into the wood which essentially makes it "plastic" with wood cell structural matrix...Personally, not my reason to do woodworking...but it has its place...


I agree. There are some awesome pieces out there that are stabilized using that process, but it's not for me. Not much can replace the natural beauty of wood. The variety of color and grain pattern found naturally is astounding by itself (for instance there isn't a drop of stain or dye in this piece I'm working right now).



Jay C. White Cloud said:


> they will last longer with a traditional approach modality...I can expand on that if you are interested?


Bring it on! I'd definitely be interested in any info on making my pieces last longer!


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## Draconei (Feb 7, 2019)

Steve Neul said:


> Personally if I were going to use epoxy in the inside I would do the whole thing in epoxy. Right at the rim where it makes the transition from mineral oil to epoxy would be prone to letting water get under the epoxy. This in itself causes the wood to expand and contract more than normal and would put enough stress on the hard epoxy to cause it to fail prematurely. Sealing the wood overall with epoxy would make it waterproof. It wouldn't have to be the thick poured on look normally associated with epoxy but enough to seal the fibers of the wood.


I can appreciate the stress that can induce. When I first started out I fully coated the inside and out with epoxy, many of them came out looking great. Unfortunately they're also quite heavy. I went ahead and fully coated the inside and out of my current piece with wax & mineral oil, hopefully I'll find it water & alcohol resistant enough that I'll feel comfortable skipping the epoxy process entirely! 

The epoxy coat on this one is probably 1/8" thick, maybe less.


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## Brian T (Nov 3, 2018)

Fully polymerized epoxies are food safe.
Not my choice at all but they're OK. 

Same for methacrylates ( plastic cups and glasses)



The organic chemistry of drying oils is full of if's and but's. Depends on carbon chain lengths,
esters vs triglycerides and the degree of saturation (hydrogenation).

Some of them, the plant oils, oxidize to create "off" flavors" but it takes a very long time of disuse.


I'm afraid that you are SOL = epoxy does not bind to hydrocarbon (oily) surfaces.
Even a fingerprint may be enough to disturb a possible bond.
In fact, hydrocarbon can be used as a mold release for epoxy castings.
One of my weekly activites, every week, for some 3 1/2 years.


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## Tony B (Jul 30, 2008)

My take on two different finishes (one side epoxy and the other side oil) would be that each side would absorb moisture from the air at entirely different rates creating different coefficients of expnsion resulting in cracking. Also, there is that line of demarkation where moisture can get in under the hard finish and cause separation and cracking. 
I never had actually done this so consider this as armchair quarterbacking.


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## 35015 (Nov 24, 2012)

Draconei said:


> ...Probably the way there is too much hype over using FDA "food safe" epoxies. Once fully cured, every brand is inert...


Hi Dracon,

You are correct in the "generic sense" of the topic...and...as Brian T. rightfully pointed out..."...Fully polymerized epoxies are food safe...Not my choice at all but they're OK...." 

They are all (for the most part) food safe when curried...

What is left out of that understanding, is not all of them (many actually) are not water proof, nor are they as durable as many are lead to believe by manufactures or those just..."using them"...without really knowing actually "what kind" of epoxy it is, and what they are actually "best" intended for. Generic epoxies are just that..."generic"...and most good applications for epoxies are very specific and intended for exactly a certain kind and formulation of epoxy...Not to just be used "willy-nilly."

I worked with the epoxies (and still do sometimes) very often at one point for creating artificial rock for climbing gyms, and for animal enclosures. I learned a great deal about there formulations and proper "intended!" applications...



Draconei said:


> ...I agree. There are some awesome pieces out there that are stabilized using that process, but it's not for me. Not much can replace the natural beauty of wood. The variety of color and grain pattern found naturally is astounding by itself (for instance there isn't a drop of stain or dye in this piece I'm working right now)...


I'm pleased that isn't your style of "woodworking" which to me has become more about "wood machining plastic wood," than actual "woodworking." An art form to be sure, and some beautiful stuff coming out of it...but not why I do the woodworking I do and teach...



Draconei said:


> ...Bring it on! I'd definitely be interested in any info on making my pieces last longer!


O.k...you asked for it...LOL...:vs_laugh:...Here goes...

Instead of making your "wade through" a bunch of other posts (many of them with some rather silly and ignorant debates) I'm just going to share some highlighted information you may find useful..?!...Feel free to ask as many questions as you need to...YOUR TURNING DESERVES It!!!

*"Rancid" is thrown around as if most folks actually know what it is or what it relates to...You really have little to worry about in this regard*...

Rancid is all about its taste and quality...nothing more. You can eat rancid oil and not much is going to happen to you other than it tastes bitter or "old," and only if you continued to eat it could it have any long term health effects. If a surface is regularly used (and cleaned) you have virtually no chance of one of these "non-drying oils" every going rancid/bitter...That is more "industry hype" than reality and them wanting you to purchase their products that are typically mineral oil based... 

None drying oils (olive, coconut) can be "cooked into" the wood. With turnings there will be some loss if unforeseen reaction wood is present, but the outcome for the survivors will be very durable and long lasting. I've studied different methods including boiling methods over the years. The recent method I've learn is from Brian T. here on the forum. I have used it now, and it is an outstanding method. It is now my new "go to" method for many culinary based woodworking items especially utensils. Below is Brian direct instructions:



Brian T said:


> Preheat your kitchen oven to 325F.
> 
> On a wire rack, over a sheet pan, slather your wooden kitchen prep tool carvings with the oil of your choice.
> 
> ...


Other possible options for your turnings are the true "drying oils" like flax (aka linseed), tung (from the tung tree and very hard when dry) or...Walnut Oil which also is a "polymerizing oil"...aka "drying oil." I would note here that walnut oil is very edible if food grade...*for recipes and consumption*...only has a shelf life of 6 to 12 months as its lipid (oil) structure does degrade faster than other natural oils. For woodworking, if kept cool and not exposed to oxygen, it has never "gone bad" on me...before it was all used up!!! 

It is the oil I got the best results from for Brian's method above. I took his procedure and used coconut oil...I like the outcome of this very much. In the end the walnut oil was the best thus far!!! 

The time walnut oil takes to dry naturally (aka without the oven) will depend on several factors but will be less stressful for your turnings as well. I would get a good "food grade" walnut oil and apply a thin coat and let dry. The temperature, refinement of the oil and also its exposure to UV radiation can accelerate polymerization. Understanding this takes the conversation into a realm of chemistry covering things like...*cationic photo-polymerization of epoxidized natural lipids*...well outside the scope of my expertise nor something "we end users" really need to get into for the most part...What it means is natural oils like walnut will dry faster than others depending on the way they are processed. Regardless however, all natural drying oils...will dry...and I like the less processed forms myself...like walnut...for such things as you are making...

Once dry there is little issue with food allergies but each person has to make there own determinations regarding this...

*Surfactant trick:* this addresses a trick some old timers would do to wood (especially those of use that work in green wood) is to pour on grain alcohol and let it dry. Two to three coats (drying between coats till the alcohol is all gone) cleans the wood and seems to proved a much better finish when all is said and done...Applying the first coat of walnut oil 50/50 with alcohol is also a good way to get it into the wood...

Let me know if I can expand on anything?


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## Draconei (Feb 7, 2019)

Brian T said:


> In fact, hydrocarbon can be used as a mold release for epoxy castings.
> One of my weekly activites, every week, for some 3 1/2 years.


I have actually been considering making a stave of epoxy and using it as a narrow window in a mug for novelty. Something like this but with a single stave rather than a pattern of them around the entire circumference. It sounds like you're the person to talk to about creating an appropriate mold that will be able to release the epoxy properly!


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## Draconei (Feb 7, 2019)

Jay C. White Cloud said:


> The time walnut oil takes to dry naturally (aka without the oven) will depend on several factors but will be less stressful for your turnings as well. I would get a good "food grade" walnut oil and apply a thin coat and let dry.


Does this mean you would recommend the use of walnut oil without the use of an oven (in my application)? I use Titebond III for gluing up the staves; I've found plenty of information about not using it when cold but no information related to degradation at higher temps. I *think* the woods would handle the heat, just unsure of the glue.

A conundrum I have come across now that I used the beeswax/mineral oil concoction on the inside is wiping out the excess at the bottom of the mug. I used a blow dryer to liquify the paste and help it soak in fully but now that it has cooled there is still a residual left that I need to remove. The mug is deep and narrow enough that I can't get my hand far enough in to wipe it out properly. :wallbash: 



Jay C. White Cloud said:


> *Surfactant trick:* this addresses a trick some old timers would do to wood (especially those of use that work in green wood) is to pour on grain alcohol and let it dry. Two to three coats (drying between coats till the alcohol is all gone) cleans the wood and seems to proved a much better finish when all is said and done...Applying the first coat of walnut oil 50/50 with alcohol is also a good way to get it into the wood...


Would DNA work in place of grain alcohol? I have a couple of gallons I bought to try drying green wood with and being the cheapskate I am (a cheapskate using exotic woods, makes sense right?) I was just curious if I could use something I already have versus buying another product.


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## Draconei (Feb 7, 2019)

The degree and wealth of knowledge y'all are providing here is amazing, so thank _all_ of you! I asked this same question on lumberjocks and received answers like "I would think you could use some acetone and then proceed". So again, thank you for taking the time to explain your logic in your answers and enabling me to make an informed decision!


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## Brian T (Nov 3, 2018)

Nah. Build a prototype and use methyl methylacrylate = fiberglass boat hull resin.
It has far better binding characteristics in wet environments than epoxy.
You have to get a plastic/resin that expands and contracts about like the wood does
or the whole damn thing is going to split into staves.



Your mug design is an absolutley stunning design idea.
I hope that it works out as well as you dream.


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## 35015 (Nov 24, 2012)

Draconei said:


> I have actually been considering making a stave of epoxy and using it as a narrow window in a mug for novelty. Something like this but with a single stave rather than a pattern of them around the entire circumference. It sounds like you're the person to talk to about creating an appropriate mold that will be able to release the epoxy properly!


That mug is stunning, and the cross over between woodworking and polymer arts...

From a "biochemical perspective" I know enough to know who to talk to...and!!!...who to listen to as well...

In other words...who's "full of sh_t" and who actually has valuable information to offer and listen to...*Brian T. is one of those I personally would turn to for..."hey what do you think???"* I also would give the folks at Ecopoxy a call and a chat with them about the subject of what you wish to do...

Granted, they are a "business" and have something to "sell" so your thoughts have to be buffered with that knowledge. Nevertheless, I know them to be dedicated to the craft of botanical based polymers and know they will send you to a "better method" if they think there is one comparatively. At minimum, you will get actual comparatives to consider...



Draconei said:


> ...Does this mean you would recommend the use of walnut oil without the use of an oven (in my application)?


From the "pure side" of woodworking and tradition (with millenia of empirical functional proof of application)...YES!!!

I would try the more traditional modalities for the above reasons, plus just the harmony of only using a natural botanical material to imbue a turning of wood with the properties to create a vessel that...at minimum...will last a user a good portion (if not full) service within their lifespan...

I would also not, combining the philosophy can cultural perspectives of Kintsugi 金継ぎ and Wabi-sabi 侘寂 I think you may find your way to creating your "own art" that could combine a turning of wood...then segmented...and joined with shards of ceramic or glass...to impart the same effect as the "mug with windows" in your photo. 

As a similar example, I did a set of wine glass back in the 70's with my mothers assistance (her design/art guidance) that took the base, stem and body of a light wood turning that match an old set of hand blown wine glasses that had there stems shattered. Following the principles of 金継ぎ I carved into pieces the wood turning and mounted them around the glass to give them new life and purpose. They ended up a gift I know not there current existence...???



Draconei said:


> ...I use Titebond III for gluing up the staves; I've found plenty of information about not using it when cold but no information related to degradation at higher temps. I *think* the woods would handle the heat, just unsure of the glue.


Hmmm...(Brian???)...I'm not sure for the stress of a turning, the use as a vessel, that would employ Titebond III for just the concerns you shared...

I think in this case I would (again) call the folks at Ecopoxy and check in with a few other collegues (like Brian)...as well as...do some very harsh empircal testing all my own to failure of sample vessel. 

IF...???...the Titebond III proved itself strong enough after my own testing, and fielded advise from collegues than it to might be an applicable adhesive for such work...

I would note, I'm more a "solid wood" and take it as I find it kind of person with turning...No judgment though, that's just my style of work...More traditional and "folkish." 



Draconei said:


> ...A conundrum I have come across now that I used the beeswax/mineral oil concoction on the inside is wiping out the excess at the bottom of the mug. I used a blow dryer to liquify the paste and help it soak in fully but now that it has cooled there is still a residual left that I need to remove. The mug is deep and narrow enough that I can't get my hand far enough in to wipe it out properly. :wallbash:


Acetone...??? 

That should remove it...then clean with alcohol...



Draconei said:


> ...Would DNA work in place of grain alcohol? I have a couple of gallons I bought to try drying green wood with and being the cheapskate I am (a cheapskate using exotic woods, makes sense right?) I was just curious if I could use something I already have versus buying another product.


That is just "moonshine" (aka grain alcohol) that has been made consumable...so DNA is virtually the same thing...

I will note (Brian??? help here???) it may leave a residual that pure "grain alcohol" would not since it is meant for human consumption...



Draconei said:


> The degree and wealth of knowledge y'all are providing here is amazing, so thank _all_ of you! I asked this same question on lumberjocks and received answers like "I would think you could use some acetone and then proceed". So again, thank you for taking the time to explain your logic in your answers and enabling me to make an informed decision!


You are most welcome...and humble thanks for you kind words...


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## Brian T (Nov 3, 2018)

Good idea to drop a line or two to the plastics companies and the adhesive people.
Normally(?), they have some Research & Development bit of a lab space where they can fool with these ideas.


Drinkable "grain" alcohol is 95% and the 5% is bonded water which is very difficult to remove to produce
what's called "anhydrous" alcohol. With tropical heat and dripping humidity, very hard to keep it that way.


If it's 95% and denatured as well, hard to say what else is in it to render it crap and so, tax free.
We got 5 gallons one time that was 10% Jet B.



You're in for some experiments. What to use and what sticks to what.
This is proprietary research = if you figure it out, it's worth selling the information.
Don't give away the farm.


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## Draconei (Feb 7, 2019)

In researching MMA a little, I'm not sure it's something I want to try turning and more importantly sanding (I work in my garage, not exactly a clean air environment). I think this may be going a little above my paygrade! 


Copied from https://www.epa.gov/sites/production/files/2016-09/documents/methyl-methacrylate.pdf

Hazard Summary
Methyl methacrylate is used in the manufacture of resins and plastics. Methyl methacrylate is irritating to
the skin, eyes, and mucous membranes in humans. An allergic response to dermal exposure may develop. 
Respiratory effects have been reported in humans following acute (short-term) and chronic (long-term)
inhalation exposures. Respiratory symptoms observed following acute exposures include chest tightness,
dyspnea, coughing, wheezing, and reduced peak flow. Neurological symptoms have also been reported in
humans following acute exposure to methyl methacrylate. Fetal abnormalities have been reported in
animals exposed to methyl methacrylate by injection and inhalation. EPA considers methyl methacrylate
not likely to be carcinogenic to humans.


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