Filling voids that go through the wall

[Don Wattenhofer]

This photo of a birch burl bowl that had a bark inclusion that was open on both inside and out. I used masking tape on the inside then filled the void from the outside with crushed pipe stone and CA. The problem I have is that the masking tape bonds to the CA and is extremely difficult to remove so I am wondering if anyone has a better solution.

 

[Tim Connell]

I use bar top epoxy, with whatever filler chosen. To contain it, I use aluminum tape which holds up to the heat of curing better and gives a better seal to the wood. The tape is expensive, but a roll lasts a long time. I usually fill before final turning, so residue isn't a problem. Not had any problems with the tape sticking to epoxy, don't know about CA.

 

[Don Wattenhofer]

I use bar top epoxy, with whatever filler chosen. To contain it, I use aluminum tape which holds up to the heat of curing better and gives a better seal to the wood. The tape is expensive, but a roll lasts a long time. I usually fill before final turning, so residue isn't a problem. Not had any problems with the tape sticking to epoxy, don't know about CA.

Is that the tape used for sealing the joints on dust collection piping, if so I have some and will try it. The epoxy would be hard to contain, I think for filling a circular void such as the ones typical on bowls.

 

[Charlie Knighton]

I like the voids.....just mho

 

[Tim Connell]

Don, the tape I use has a paper backing that is removed to expose adhesive side. Sorry, don't remember brand name or anything, but it's main use is HVAC.

When I've got larger circular areas to fill, I use hot melt glue to create a dam around the fill area. Sometimes the hot glue sticks too well and pulls fibers when being removed. Another reason I do most fills before final turning.

 

[Don Wattenhofer]

Don, the tape I use has a paper backing that is removed to expose adhesive side. Sorry, don't remember brand name or anything, but it's main use is HVAC. Yes I have the same thing that I used to seal the joints on the round metal ducting for my dust collector.

When I've got larger circular areas to fill, I use hot melt glue to create a dam around the fill area. Sometimes the hot glue sticks too well and pulls fibers when being removed. Another reason I do most fills before final turning.

I prefer the CA because I can position the piece do a small section then re position to do another portion. I do understand that the epoxy would have more visible depth but it would seam that damming with hot melt would be prohibitive on a void that included more than say 20 degrees of ark. Note the void in this particular piece is close to 180 degrees and the inside diameter is about 5" meaning the dam would be 2 1/2" high in the center of the void, so unless I am not understanding your method it would seam to be unworkable..

 

[Tim Connell]

You understood correctly, filling that particular piece with epoxy would be a challenge.

If I had to fill a piece like yours with epoxy, I'd start at one end of the void and do a small pour. As soon as that set, rotate the piece a few degrees and do another pour, etc. As long as the epoxy was still sticky and hadnt fully cured, it should still bind. It would be a pain, but could be done.

This bowl was done like that, I think I poured epoxy 8 different times to fill voids around the curve. The hot glue was already removed when I took the picture. Although you can't really see it in these pics, the split/void went down the side and almost to the center of the bowl.



Finished bowl.

 

[David Shombert]

I've dealt with this problem by putting a layer of wax paper underneath he tape, so that wax paper is covering the void and the tape is holding the wax paper in place. If that makes sense. It's tricky because it's hard to get the paper flat against the curved surface, but it can be done. I don't think I've used this on an area as big as what you show above, but it worked well on a smaller piece. Worth a try, maybe.

 

[Gerald Lawrence]

I have used the method Tim showed you, but again that is using epoxy and I used blue painters tape. Worked well and for some inside and outside had to do that 4 to 5 times.

 

[Don Wattenhofer]

You understood correctly, filling that particular piece with epoxy would be a challenge.

If I had to fill a piece like yours with epoxy, I'd start at one end of the void and do a small pour. As soon as that set, rotate the piece a few degrees and do another pour, etc. As long as the epoxy was still sticky and hadnt fully cured, it should still bind. It would be a pain, but could be done.

This bowl was done like that, I think I poured epoxy 8 different times to fill voids around the curve. The hot glue was already removed when I took the picture. Although you can't really see it in these pics, the split/void went down the side and almost to the center of the bowl.

View attachment 32602

Finished bowl.

View attachment 32603

View attachment 32604

I have to say that 8 pours would amount to more time ( probably about 8 times) than it took to remove the tape stuck to the CA.
For large voids I have used epoxy putty to build up the area then undercut with a Dremal tool and refill the surface with powered stone and CA.
These 4 Mesquite Burl bowls had many voids that were part of the growing process of the tree and then the worms that attacked it later. Several of the voids needed more fill than just the stone so I went the putty route then finished off with turquoise powder and CA.

 

[Tim Connell]

Thanks for the mention of epoxy putty, I forget about that product and it's usefulness.

You are correct about the time. It was an experiment to see what I could do, and how it would look. If you are in a hurry, not the way to go, but, the only time I'm in a hurry, is usually right before Christmas...

 

[odie]

Don't know if this suggestion is helpful, but I found that cloth hockey tape does not stick to epoxy after it dries. Just peels off.

......haven't tried it on CA though.

-----odie-----

 

[Tim Connell]

Don't know if this suggestion is helpful, but I found that cloth hockey tape does not stick to epoxy after it dries. Just peels off.

......haven't tried it on CA though.

-----odie-----

Thanks Odie, its probably a lot cheaper than the aluminum tape too.

 

[John Tisdale]

Suggestion: leave bark around the opening and punch through after you're done turning - make the "opening" the feature. The birch piece in your picture is good stuff - I'd call it a vase.
Judging from the piece in your avatar, you do great work. Next time your showing your work, see which one draws the comments and accolades - you may find yourself looking for "logs with problems".
Please send a pic of the finished piece.