advice on turning an old dry burl

[tony_A]

I'm new to wood turning and am after some advice on how to turn dry and deeply cracked white gum (E. viminalis) burls. The trees they came off are long dead, have been on the ground for a long time and are not much more than shells.

Below are some blanks that I rounded off with a scraper. Can see shattered grain along the edge of the cracks and have had some chunks break out along the cracks.

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Are burls like this better stabilised with resin and does this limit the options for finishing later on. I like oiled finishes but not sure how it would go on a surface like this where the oil can not be wiped off within the cracks etc.

I have used a scraper for rounding the blanks but is this the best tool to turn burls considering that in some cases the grain has got more angles to it than a playboy photo shoot.

Comments and suggestions on how to turn and finish this type of surface appreciated.

Tony

[dai sensei]

Stabilising help harden the timber but does not fill any cracks, filling is done with casting, but the resin will only get to cracks exposed not internal ones. Personally I would still cast it, but I am a caster, there is a lot of work doing it properly.

You could fill the cracks with coffee grinds, or something else like metal powders etc, glued in place with thin CA (leave to dry properly as CA takes time to dry at depth). Then as more cracks are exposed, refill them as required, this does work pretty well. Don't use sawdust, sorry IMO it looks like crap. The only disadvantage is the smell of CA as you turn and sand.

Whether you cast of just fill the cracks, the bowl can be finished as normal, i.e. as you would normally finish a bowl (oil or what ever).

As for what tool, a bowl gouge.

[hughie]

I have done many of these and its case of keeping your eyes and ear open to any changes as you turn. Turn it slowly as it lessens the nasty surprises, and make sure your tools are sharp. Have a good look at it and what you want to turn before you start and sort out the bad areas or suspect ones. What I use is 5minute Araldite, there a couple of products on the market that mix and dispense at the same time with long fine nozzles. With these, I inject the Araldite deep as I can into the bad area/s. Most of the bad cracks etc will be black and the colour of the glue will blend in and appear black and so won't be noticed. The trick is not to fill the whole crack but rather make small connecting points much like tack welding. Now you may have to do this several times as you turn the piece so keep an eye open and regularily stop to check it out. Will post a few pics later of ones I have done.

[turnerted]

What Neil and Hughie said .Just keep out of the line of fire and maybe wrap duct tape or packageing tape round the outside when you start hollowing . The end result will be worth it .
Ted

[hughie]

Here you go

[smiife]

Hi tony, yeah I have turned a few of these blanks , they look
scary but if you are careful they are surprisingly stable , with
the bowl i turned the bottom and made a large tenon , and
turned it around wrapped with shrink wrap, the hollow form
I used cloth tape on the outside while hollowing......
Hope this helps .....slowly , slowly ,

[tony_A]

Thanks smiife
The bowl in the second photo looks really interesting. What did you finish it with?
Tony

[smiife]

Thanks smiife
The bowl in the second photo looks really interesting. What did you finish it with?
Tony

Hi tony , the second photo Is a hollow form , finish was sanded to 800g
Danish oil brushed on and left to dry , sanded again with 800g , and
finished off with a nitro cellulose lacquer sprayed on , I think I did the
bowl the same way .....

[artful bodger]

Interesting to hear what others think of burls like this (aerated ones).
I like to give them a wide berth.

[tony_A]

Thanks Hughie
Think I've seen some of your work before. Gives me something to aspire to. As a matter of interest what finish would you use on this type of bowl.
Tony

[hughie]

Thanks Hughie
Think I've seen some of your work before. Gives me something to aspire to. As a matter of interest, what finish would you use on this type of bowl?
Tony

It varies on those two Wipe on Poly satin by Minwax, sometimes Danish Oil my own mix. The truth be known this type of burl is one of my favourites to turn and carve.

[smiife]

Interesting to hear what others think of burls like this (aerated ones).
I like to give them a wide berth.

Hi AB, where Is your sense of adventure ? :o

[tony_A]

Interesting reading your experience in customers preferences above Hughie. When making product for sale you obviously need to have the customers in mind. No such problems here, well apart from well one fussy customer whose kitchen it will end up in.
Turned a couple of burls over the weekend and had one fail and a couple that went OK. Should have had the camera a little out of focus as the less than perfect finish seems magnified. The bowl was still reasonably green despite the condition of the tree and it has already distorted significantly with drying. Adds a bit of character.
The larger bowl has several large cracks and I wasn't game to take it any thinner.

[Nubsnstubs]

Tony, you did a good job of keeping that piece together. One word of caution. That particular piece with all those cracks probably should have had a tenon instead of a recess. Tenons compress, and a recesses expands, possibly causing the cracks to widen and become more unstable.

Another thing I've been doing lately is drilling dowel holes across cracks, and inserting dowels I've made to help stabilize the stuff I do. There is a small learning curve, but well worth it if your stuff stays together. I use the Kreg drill bit with the small point and 3/8" body. ............. Jerry(in Tucson)

[tony_A]

Thanks Jerry
Your point is very valid. Was using a slow speed, keeping a close eye on the amount of solid wood on either end of the crack and stopping regularly to check its stability (and making sure I was not in the line of fire in case it did break).
I like your idea of using dowels to hold major cracks together. This sort of exchange of ideas is what makes these forums great.

Thanks
Tony