Healing Cracked bowls

Hi Gerald, Thanks for sharing your info about the healing powers of watery glue. I remember that several good turners have recommended it, but recently it seems the enthusiasm has waned. I assume that 'healing' by soaking means that the crack walls are drawn or pressed together by the diluted glue, not 'repaired' by being glued together? Haven't tried it myself. I'm too old to wait for glue to dry.

I'm no statistician, but even if it doesn't rise to the level of being "evidenced based" which I see by the paper is the 'in-word' used by politicians involved in health care (they could use some glue on themselves) your results gives us Crackers with cracked bowls some hope.

At least, 50% is a coin flip and a much better chance than my cracked NIP bowls have for healing themselves. Some actually do. Whew 60+ bowls with only 5 cracked. With that record I'd forget the glue and sell the five as art. If you weren't a good net friend, I'd accuse you of either bragging or fudging. Anyway you've been too busy to get into any real trouble. :)

BTW, I've plagiarized many of your great philosophical 'sign offs' Keep em coming.

Turn to Safety, Arch Fortiter

...and I've been told I'm impatient!! LOL!

Wally Dickerman was the person to first provide this cure for cracked bowls. He recommended 50-50 white glue and water. I had my doubts about the cure, but Wally has been turning three or four times as long as I have, do I tried it on a 15 inch rough turned salad bowl that I had planned it as a gift for a friend who had purchased a new home. I had to purchase two gallons of white glue and put it with two gallons of water. I soaked the bowl for a couple of days and took it out. The crack was still open. I said to myself, Wally it didn't work. I threw the bowl onto a pile of wood in the yard, where it was rained on for a couple of or more. About a week later, I walked past the bowl and noticed that the crack (which had been about 3/8" at the rim) had completely closed up. I put it in the shed to dry before final turning. The crack never opened up again. The friend is still using the salad bowl (been about four years now) and it only has a fine line where the crack had been. Just my experience.

Barring you spent a lot of money on the blank, cracked bowl => Firewood, move on. If you spent a lot of money on the blank, you can call it art, or fill the crack with turquoise and call it art, or toss it in the firewood pile and ask yourself why you spent a lot on a bowl blank.

...MHO.

1. No money at all in the blank, but a little time. The jug of glue was already there and not being used. The water was free. The one that worked was a freebie since it was destined for the dump. I don't use firewood.
2. If I ever DO have an expensive bowl that cracks, I now know that there is some possibility of fixing it.
3. I'm moving, I'm moving on.

In message , Gerald Ross writes

One thing that springs to mind, is like most things , failure occurs at the weakest point.

So as the wood dehydrates, we get shrinkage.

If we then have a weak point, and the forces involved in the shrinkage are strong enough, we will get a crack, starting at the weak point.

Now if we re-hydrate the wood, the wood will likely return to the shape it had before, dehydration, hence closing the gap. The adhesive, in the solution causing the surfaces either side of the crack to bond.

In addition to this the adhesive provides reinforcement for the wood around the crack, so that as the wood again dehydrates, it is less likely to crack again, in this location, though it could be that the forces are strong enough to find a new weakness.

Fred... When you dried and turned the bowl, was the wood normal, or glue impregnated?

Just thinking back to some of my LDD experiments and trying to turn soft, colored bowls that never went back to natural color of texture..

mac

Please remove splinters before emailing

Hello Mac,

I don't recall any discoloring of the wood. It was a nice maple bowl. It final turned easily with no sign if the glue.

Fred Holder

I wrote about this a few years ago on this forum, and as it happens I had to fix 2 bowls in this past week with my "wood soup", one just because I was in a hurry even though I know better, where I got a couple of checks in the lower part of a square natural edge bowl, wrapped a water/glue soaked rag around the outside and placed another soaked rag into the inside of the bowl, placed a plastic bag around it and let it sit overnight, that was enough to close the checks back up and the bowl is dry now and finished, and the wood stayed close, there are two very narrow lines were the splits have been, but I don't think anyone would notice with the other lines that are in the sapwood that look much alike, anyway I saved my time spent and a piece of nice black walnut. The other one is a trial piece with a double wing and as it happened there was a small twig showing close to the edge of one wing, I should have placed a staple in the edge to make sure it wasn't going to split, anyway the next day when I pulled it out of the paper bag to do some more work to it had a split about 1½ long and 1/16 wide, again, I placed a water and glue soaked rag on the outside of the wing and set it in a plastic bag to soak for the night, the next day the split was closed, removed it from the plastic bag and wiped it clean and it is now drying in a brown paper bag, the split I can't find even though I know where it was. Again I have saved my time I did spend on this trial bowl, and a piece of wood. I don't do this glue thing very often as I don't usually have splitting turnings very often, but I never let a bowl sit without checking them especially the first couple of days, so wood isn't dry and has sat with wide splits in them for a while. I have always had good luck fixing the small splits when the wood is still wet and the splits/checks are still small, works for me ;-)) Have fun and take care Leo Van Der Loo

I never tried this trick, but it sounds like the glue/water mixture soaks into the wood, swelling the crack closed, When the wood again dehydrates, just the water evaporates leaving the glue to keep the crack "swelled" shut. I reckon if just the holding power of the glue forced the crack to stay closed, you would stand a better than even chance the crack would re-appear there or somewhere else. The glue that remains in the wood keeps it in a swelled/stable state forever.

In other words, I'm thinking the bonding part is minor compared to the left over swelling? Just my guess though, not sure.