Epoxy filling voids

[Jim Hipp]

Turning a bowl from a piece of pecan that was stored outside on the ground for more than a year. On first look it appeared to be nothing but rot but on closer inspection there was solid wood present. I managed to get it securely on the lathe and have turned away much of the surface rot but am left with a large -5.5" X 2"- chunk missing at the point where the side would angle toward the base. I could turn away the solid wood around the missing chunk but wouldn't have much of a bowl left.
Think I will try to fill it with epoxy.
Questions
Which type of epoxy? Looking online there many different types for use in different applications.
What can I use to color it? On You Tube some use a powder and some use a liquid coloring agent.
What type of material can I use to make a dam around the area where the large chunk is missing.
Thanks for any help

[John Hart]

Hi Jim....If it were me (and that does not mean I'm correct or anything like that), I'd use a marine boat resin in this application. Building a dam is always fun. I did a couple vessels covered in resin and it can get complicated...If I were doing yours, I'd probably cut a piece of aluminum flashing to get the curvature (slightly larger than the piece's curvature) and tape it in place with duct tape or strong masking tape.
I've only had experience with the liquid dyes....worked well for me. don't know anything about the powders.
I'd be interested to see a picture of your gap....and then your final solution :)

[Edward Dyas]

That big of a spot you might try mortising a piece of wood in there to fill it. If you just want to fill it you could mix a universal tinting color into bondo to fill it. Just make the color a little less red to allow for the red in the hardener.

[Alex Zeller]

I've never used it on wood, yet, but I use 3M Aluminum foil tape quite often for doing things like epoxy. It sticks great and can be formed. There's no stretch so if you have multiple curves it's not going to stretch like vinyl tape would.

[Timothy Thorpe Allen]

I haven't used it in turnings yet, but in other similar applications -- WEST system marine epoxy thickened (and colored) with sanding dust from the species of wood being filled.

[Richard Coers]

I assume you've seen the quote, "Life is too short to turn crappy wood." Is wood in short supply around you? Around here, I have about 2 lifetimes of wood stored away. Ash trees are being taken down by the hundreds because of Emerald Ash Bore. I would not make the investment in resin and labor to save that, find a new chunk of wood and have a new bowl in short order.

[Jim Hipp]

I am using this as a practice piece to attempt things I have never tried before even though I have other wood available. And I do tend to be a bit determined at times. Maybe stubborn.

[Alex Zeller]

If you don't try how will you know what you can do?

[John Hart]

Yup...I agree. If it weren't for frivolous experimentation, I'd never know how far I could take my craft. That's the adventure. :)

[John Keeton]

Deteriorating wood may not bond well. Getting smacked in the face with a 5” chunk of cured epoxy or whatever you may use doesn’t sound like a situation I would risk just to “try things I have never tried before.” Be safe and use a solid piece of wood for your experimentation.

[Chris A Lawrence]

Do the edges of the void look natural? Around here people pay extra for fancy holes and voids. Dont pour to thick if your using duct tape as a dam. I learned the hard way when my first pour ended up in the bowl i was using to to keep a void level. The heat melted the and released the tape at the edges of the cardboard i was using. The next attempt was in 2 pours a small pour the seal the edges then a pour to fill the void.

[John Hart]

My oh my....what has happened to the Sawmill Creek Turning Forum? Many years ago when I first joined...before I knew what a tool rest was for....this place was like a family. People posting their stories and pieces....maybe 20 per day....everyone having a ball critiquing and offering tips. No one afraid to try new things...no one in fear of disapproval. Just everyone having a good time learning from everyone. Good and bad.
My first piece was a disaster. But I posted it. No one made fun of it....just encouraged the next attempt.
Andy Hoyt....a couple months before he died, called me at home one evening. I didn't know Andy except from the Creek. He was so sad he had so little time left and that he would miss everyone here. God he loved being here and playing around with everyone.
But that was another time.
We've lost something.
No one posts their pieces anymore. Most of the chatter is about tools.
Someone asks advice about something they want to try and get a finger wagged in their face...."Don't do that!!!!"
Well back in the old days...the advice would have been..."Cool!!!...be careful though...stay clear of shrapnel....pay attention to your technique and stay clear"
But not today.
What has happened to my turning forum?
I think it's time to get back to the adventure.
Life's too short.

[Robert Hayward]

What has happened to my turning forum?
I think it's time to get back to the adventure.
Life's too short.

My sentiments exactly. Thanks for saying it John.

[John Keeton]

A few thoughts related to John's comments on lack of adventure. "Back in the day" there was a lot more camaraderie on the creek and folks posted a lot more. I started turning in 2009 and received solid encouragement and advice from folks on the creek. Most of those - Keith Burns, Curt Fuller, David Keller, Steve Schlumpf, just to name a few, were accomplished turners doing artistic work. There was enough exchange on the creek that most everyone knew the skill level of those posting. The mission of turning seemed to be - be safe, have fun, and be creative, with the emphasis on "be safe" as without that, having fun and being creative were remote possibilities. I received considerable advice from those folks. They asked the right questions, and gave me information that was valuable. Sadly, most of those folks no longer post their work or participate on SMC. In fact, it is on rare occasion that I post anymore and then only to applaud the accomplishments of some of my students at my John C. Campbell classes. While I do not use social media, I think that is probably where folks are gathering instead of on forums such as this.

In this situation, none of use know the skill level of Jim, we do not know the tools he uses, his techniques, the speed at which he turns, and most importantly, we do not know what Jim means when he says "to attempt things I have never tried before." Do those "things" relate to tool use, embellishment, etc. What we do know is that the wood in question has considerable rot. We know that there is a large "missing" chunk of wood, which would seem to indicate it is not a natural void, but we do not know for sure. There are no pics of the wood, no indications of what Jim intends to "attempt" and no indication of the shape or size of the remaining wood, nor the speed at which it will be spun.

Without knowing these things, it seems imprudent that he undertake vague suggestions as to how to deal with this particular inquiry. It would seem a better approach would be to seek more information from Jim, along with pics of the wood, an explanation of what he hopes to achieve, etc., before encouraging him to try adventuresome efforts.

When I teach I have a variety of students - most with several years of turning behind them, some not. But, universally, I find that most of them over estimate their skill level. Safety is the PRIMARY concern. I shudder at the thought that I led someone to attempt something that got them hurt.

Yes, in the past I have tried techniques that presented potential for not going well. But, that was my choice and even though I learned from them, without knowing considerable information about another's abilities I would never suggest that someone else try those techniques. Given the injuries and deaths that have occurred in the turning world from flying debris, often involving experienced turners, I am much more aware of the potential for injury. Many folks have not had instruction, supervision and guidance from mentors and the risks are much greater for them.

I don't intend to further debate the suggestion of "frivolous experimentation" and this will be my last post in this thread. I just hope that good sense will prevail here and Jim offers up more information so that an intelligent exchange can occur about what might be his best method of accomplishing what he hopes to accomplish.

[Jim Hipp]

Hard to get an image that is detailed enough.
415500
415499

I have been working at turning bowels for a few years and was never happy with my efforts. Earlier this year I considered giving up and selling everything. And then I realized that I was letting "perfect" get in the way of "good". And that realization took a load off and now I turn and what I do is the best that I can do on that day. To heck with what anyone else thinks. Turning is now a lot more fun.
This piece of wood gave me an opportunity to do something with epoxy and that was my goal. Just give epoxy a try and learn from the experience. That doesn't mean I want to be reckless and get hurt in the process so comments about what could go wrong and produce a wreck are appreciated.
I have dug out the rot with the screw driver ground into a point shown in the picture. Strangely enough the black wood is the hardest The light colored wood in the image was soft and I dug out what I could. Currently a sharp point will penetrate the soft wood no more than 1/8 of an inch.
FWIW-I tend to turn in the 400-500 rpm range and use Irish grind, Easy Wood tools and a heavy duty scraper when appropriate.

Thanks for the comments and criticisms.

[John Hart]

Looks to me like it would work Jim...at least as far as configuration. Not sure how the moisture content will affect adhesion. I've had pieces in the past that I had to heat up with a propane torch to get some dryness and that worked ok. Other times....well....not so much :)
Fun times

[Dave Mount]

I'm a "funky wood" guy and I do a lot of void filling with epoxy, but in almost all cases I rough turn green, dry the piece, then do the required epoxy fills and finish turn. If there are cracks or defects I'm worried about staying in place during initial turning, I usually use cyanoacrylate to reinforce things enough to do the roughout. Turning any piece of wood is potentially dangerous, though certainly some more so than others. Best to assume that any piece of wood could fly apart at any time.

I agree that the nature of the void is such that I wouldn't be overly concerned about the stability of the fill, if it were dry. Not saying it wouldn't work green, just don't have much for experience with how well epoxy bonds to green(ish) wood.

Some thoughts if you decide to plunge ahead:

When doing the fill, I would begin by soaking the area well with straight epoxy with no additives (fillers). The goal here is to get the good penetration of the degraded areas. If you just begin with epoxy with filler, the fill can end up kind of "starved" for epoxy if a lot of the epoxy soaks into the wood and leaves the fill area too dry.

Epoxy resin changes in viscosity a fair amount with temperature. You'll get better penetration if the resin is warm (say 80 F). It will also set faster at this temp -- choose your hardener accordingly (see more on this below). Warm epoxy will also purge bubbles better (lower viscosity).

Fresh epoxy bonds completely with uncured (still soft) previous coats, so this initial soaking is a first step in a "fill session". When the wood seems to have been saturated with straight epoxy, but before that initial epoxy is set, add the main fill. Assuming that your fill will be opaque and not clear, you're not going to see much of that funky texture that's showing now (which I think is kind of cool). If you just use only tinted epoxy (no filler), my own sensibilities are that it's going to look kind of "plastic" and not in keeping with the "organic" features of the wood. For this reason I would use a semi-chunky fill, so that the fill has some visual texture. Were it me dealing with this piece, I would use a combination of ground coffee and crumbles of bark (say 1/8" to 1/4" max). Epoxy soaks into both pretty well and they end up giving the fill a pretty uniform hardness, which helps with both final turning and sanding.

The ground coffee will give the fill a dark brown color. In most cases, I find I get a better look from filling far darker than the surrounding wood than trying to match it. However, you can use a lighter color filler (e.g., wood flour) and tint it with Transtint dye or pigments (just Google epoxy pigment) if you have a particular color in mind. A lot of people say they just add enamel paint, though I've not done that myself. If you want to go psychadelic, get some mica powder (gives a pearlescent look). I tend mostly toward a more natural look, and am usually trying to keep the fill in the background visually, rather than accentuate it. It's funny that dark brown fills generally don't draw that much attention, even if it contrasts pretty strongly with the surrounding wood. But some folks do flashy things with fills.

This is not a job for 5-minute epoxy, you want a slower cure so there's time for it to soak into the wood, and for bubbles to rise out of the fill. I would use a slow hardener for the initial coating of the wood -- you want this to set up slowly so there's maximum time for penetration. You could use a medium or fast (but fast is not the same as 5-minute epoxy) hardener for the main fill.

I get my epoxy from raka.com (no affiliation, just a satisfied customer). They offer kits (resin + hardener) in different volumes at what I've found is a very good price. One of the really nice things is they will do is to sell you kits that include more than one hardener and still give you the kit price. For example, if you order a 3 quart kit (2 quarts resin and one quart hardener), you can get it with 2 quarts resin, one pint fast hardener, and one pint of slow hardener at the same price. Their website isn't very sophisticated -- if you want to do a special order like I just described, call them to order.

I find it much easier, and much more accurate, to mix by weight rather than volume. For $5 or $10 you can buy a cheap digital scale that will measure to the tenth of a gram. The raka 2:1 (volume) resins mix in a 100:43 ratio by mass. Yeah, that sounds complicated, but there's a calculator on your phone if you can't do it in your head. Multiply the grams of resin by 0.43 to get the hardener mass. 10 g resin, 4.3 g hardener. Buy some small (like 2 oz) disposable plastic cups to mix in.

Epoxy produces something called an "amine blush" when it cures, which is kind of a greasy surface layer. If you let one application of epoxy cure before you add the next, this amine blush will interfere with the adhesion of the second layer to the first. That's why I suggested doing multiple fill steps all in one overall session. If you do have to pause, you need to wash the amine blush off, or sand the previous layer well in order to get good adhesion. Since you're relying on this fill to stay together while you're spinning it fast, you want to make sure there is good adhesion. Best is to do it all one overall session where each addition is going over an previous layer that is not fully cured.

It's hard to fill big voids on the outside of round things so that the fill is complete -- you have to build a pretty good size dam. For that reason, it's often better to fill them before you're too close to final dimension, so that if the fill is a little shy it will still turn down to round.

Have fun!

Dave

[Boyd Parks]

Hi Jim, I'm a novice turner and by no means any expert on this, but I've been experimenting a little myself filling voids. with Alumilite Clear cast I bought from Hobby Lobby. I added Alumilite mica powders for color, with overall good success. I have used vinyl tape for the dam and sometimes had to pour more than once. It isn't expensive and does add stability and color to the bowl or vessel. My biggest problem so far has been trapped air bubbles. I do like the idea of bending light sheet metal to make a form. Good luck!

[Jeffrey J Smith]

I agree with Dave’s post on using epoxy. I got years of experience with West System epoxies through an ill-advised acquisition of an older wooden boat..still use epoxies even though the boat is long gone. Amine blush is usually easily washed away with a little soap and water.
The option is to add a patch to reduce or eliminate the epoxy fill.
I had a piece of Black Acacia the was destined for a large fruit bowl - 18” diameter. Originally planned to fill the bark inclusion with epoxy, but decided that, since it didn’t need to hold soup and it was holding together through the roughing process just fine, to throw is a few dutchmen/butterflies to hold it all together.
Decided it was a good opportunity to do through butterflies - mortise deep enough to show through both inside and out. A few in process photos - no finish yet...415506415508415509

[robert baccus]

Roger that John Hart...We are told by the media that everything will hurt you or kill you. Every hobby I ever enjoyed, and every job was dangerous. Including Offshore oil, Forestry, offshore fishing, sailing skiing ect. Did we get banged up--for sure--so what. The same in turning for 30 years but we were not made to be safe and comftorable and bored. Life is too short to sit on he bench and not try the unknown and untried. I have discovered more unique procedures and tools than I ever read about and never had a lesson. Learning something yourself is far more pleasurable than being trained. Sure we learn from others and should share our tricks but we should not be discouraged. It's supposed to be fun. The Forum is lacking in spontanity and enthusius as is our local turning club.. Far too many clicqes and push back,s in the crowd me thinks. Too many regulations and rules in this world now. If you read any history or economics this is readily proven. Have fun and experiment your heart out.

[John Hart]

:)
Cool Bowties Jeffery!!

[Dave Mount]

Agree, love the dutchmen. Can you outline your process for cutting the mortises?

Dave

[Jeffrey J Smith]

Agree, love the dutchmen. Can you outline your process for cutting the mortises?

DaveI use a standard inlay kit (bushing and matching bearing and a spiral bit - I think mine is from CMT but there are several on the market) with a template hot glued to the blank. I generally cut my own templates from expanded pvc board like Sintra (ask for scraps at a sign shop). You can easily cut 3mil or larger with a utility knife. 3mil seems to be stiff enough and holds up to the hot glue well.
The 1/8” spiral bit needs to be able to cut to a minimum of 5/8” deep plus the thickness of the template - need to look around for extended bits.
Chuck up the bit in a trim router, put on a respirator and make small cuts until you’re about 5/8” deep. 1/8th inch bits don’t have a lot of cross section for heavy cuts at depth. Go slow. Finish corners with a chisel or knife.
Same template makes the dutchmen on whatever stock you like.

A couple of thoughts that came up as I wrote:
Seems like a 1/4” bit would go faster, but then these are the largest I’ve done so far - most are smaller - and I don’t think I’ve seen an inlay set for a larger bit. Now the google machine needs to be fired up...

Play with the template - I mark up the blank with a pencil til I’m happy with the layout.

Be aware that going all the through to break the inside surface means that the dutchman is probably significantly weaker than one that only goes partially through the bowl wall. There’s less glue surface and a higher proportion of end grain. I didn’t think it was an issue for a fruit/display bowl.

[Glenn C Roberts]

Jeff, would both the dutchman and epoxy work, completely filling in the void?

[John K Jordan]

Hard to get an image that is detailed enough.
415500


From the picture it looks like some of what's left may not be very strong. Could it come apart, epoxy or not, as the inside is removed?

A friend of mine turns things which stayed together when the outside is shaped would easily disintegrate when hollowed. He solves this by turning the outside first then wrapping it with reinforced strapping tape.

JKJ

[richard shelby]

I use lots of epoxy. I buy regular "bar top" epoxy by the gallon it's a 1:1 resin catylist mix. Like Dave, I'm a 'funky wood" guy, turning blanks green and filling the voids after they dry for final turning. Sometimes turning a funky piece while green can be dangerous. You can't see if that fissure goes all the way thru and may let go sending schrapnel straight in your face. Face protection is a must. There are also goo, sap, beetle larvae, and carpenter ants in the mix. Cyanoacrylate will help sometimes and it may be helpful to brush on an epoxy/acetone mixture. Acetone is a solvent for epoxy and will not inhibit the cure, but makes epoxy penetrate funky wood. For large voids, dams of masking tape, and pieces of milk jug plastic taped on will help. Adding sawdust or coffee grounds to the epoxy will inhibit the tendency of epoxy to drip and when cured, has the apperance of a bark inclusion. What customers really like is the addition of colored stone to the mix. I get mine pre-ground from https://www.etsy.com/shop/Thegrindingshed. (not affiliated) Great people with LOTS of different colors and particle sized of gemstone and other minerals. My favorite is chrysocolla. Some of the minerals are quite high on the MOHS (hardness) scale and will dull an M42 gouge immediately, so carbide is necessary when finishing stone inlays. Abrasives are a must for final finishing. With bar top epoxy after an overnite cure you can proceed to final finishing, but often more than one pour is required. Always do an experimental cure before you mess up a piece of wood. Sometimes the temperature and mixing errors will keep the mix from hardening, so be sure of your mixing method, whether by weight or volume, and adhere strictly to your chosen mixing protocol. Epoxy seems to have a long shelf life. I have had epoxy for 10 years which seemed to be OK.415556

[Jim Hipp]

Thanks to all for the comments, advice and concerns. The detailed explanation on the use of epoxy by Dave Mount will be of help for many projects to come.
If this piece holds together and I am able to finish it I will post a picture or two. Thanks again.

[lynn cranmer]

I use the aluminum tape on my bowls all the time. Agree,it sticks great and you can form dams etc. I suggest using some hot melt glue around the edges to prevent the epoxy from seeping under the tape. I sometimes reinforce it with painter's tape just to be sure.

[John K Jordan]

...
If this piece holds together and I am able to finish it I will post a picture or two. Thanks again.

I'm certain the community would like to hear about your experiences, good or bad!

JKJ

[Jeffrey J Smith]

Jeff, would both the dutchman and epoxy work, completely filling in the void?
Sure - You’d still have the problem of creating a dam. I use hot glue to build up a fence around the void.

[Tim Rinehart]

Hey Jim, I echo Boyd’s suggestions using the Amazing Clear Cast. It is a slow cure, overnight. I’m in the middle of a bowl project that involves a large gap in the crotch area and if left as is, would not be confident turning it.
Some key things to be aware of once you accept that this is not solid check free wood, are following.
1- The wood should be dry/stable so it doesn’t move and potentially lose bond to any filler.
2- The success of the fill will be much better if you remove all punky/loose/rotted wood. You want the epoxy to bond to solidsolid wood. I spent a lot of time with dental picks and pliers to clean out the 10”x1” crevasse.
3- Use some sanding sealer or dewaxed shellac to seal pores of wood where the epoxy will come into contact, this will help prevent bubbles from the pores.
4- Amazing clear cast works well with Alumilite dyes and pearlescent pigments, I think mixing in the part B which is heavier is best so you can give bubbles a chance to rise before mixing in part A.
5- Lastly, try to pour in a way that doesn’t trap air that will show up as a pocket.

Good luck and be safe!