Cracks in bowls - Photos and Question

[Ephraim Stern]

Hi, I am new to these forums. I am a newbie wood turner with many questions and this looks like a great place to find knowledgeable people with turning experience.

I recently purchased a Delta Lathe for the company that I work for and I decided to take a look and see how it works. Since then I have been spending all my free time in the shop relaxing on the lathe.

Two of the bowls that I turned cracked on me and I am not sure why. I was browsing the web for answers and I found this forum.

The first is a natural bowl turned from a piece of cherry that I got on EBay. When I turned this bowl the wood was moist inside and showered me with cool shavings. I turned it to about 3/8" and went home, when I returned the next day it had all the cracks that you see in the photo. Is there some way to prepare the wood so that it does not crack?

My next cracked bowl was on my second segmented bowl made from a variety of woods. The Dark wood in the center of the pain cracked a day after the piece was finished. A few of the joints are no longer flush and it appears as if the wood is trying to curl.

If my memory serves me right that wood is called Bocote. When I first tried to glue it the glue did not hold since the wood appeared to be very oily so I tried soaking the wood in Acetone before I glued it and then the joint held. This bowl was also turned very thin around 1/8"

Thank you in advance for any advice.

[Dennis Peacock]

Ephraim,

I have an article in the Articles/Reviews section of SMC on processing a bowl blank. The most successful method I've found so far is the Denatured Alcohol Drying Method introduced by Dave Smith.

Welcome to SMC and post more of your work. Looking good!!!!

[Ephraim Stern]

Dennis,

Thank you for the response and great easy to follow photo instructions. I can definitely follow your instructions so my problem is solved but I am now disappointed since I never learned patience and I get the feeling that there is no overnight solution.

Oh well.

I guess I need to limit my purchases to kiln dried lumber.

Thanks again.

the rest of my collection.

First segmented bowl - Poplar and Maple

Segmented Pentagonal bowl - Poplar and Maple

[Andy Hoyt]

Ephraim - Welcome!

Nice stuff for your early work - very nice indeed.

Lemme guess - scrounging scrap from work, huh?

[Ephraim Stern]

Hi Andy, Thank you!

You got me pegged exactly! I am very lucky since I work in a factory that goes thru around 3,000 b/f of lumber a week and everyone in the shop is always looking out for a piece with nice figure or odd color for me to work with.

The only thing I can complain about is the variety. All we work with is Maple and Poplar. Everything else I have to purchase online which makes this hobby very expensive to maintain.

I am dreaming of the day when I can move somewhere with trees.

[Andy Hoyt]

There's always Central Park!

[Ephraim Stern]

That’s a great idea! Since I started about a month ago I have asked over 30 people if they had any ideas on how to get wood without going broke and you are the first to offer me such a simple solution. Monday I will go hunting for wood and let you know what happens.

I checked out your website and your work is incredible. I cannot fathom the level of focus and patience that is required to complete projects of such difficulty.

[Dennis Peacock]

Why not look around in the near by neighborhoods for pruned trees, downed trees just waiting to be hauled off and such as that. I've found a lot of wood that way. Just an idea. :)

[Bernie Weishapl]

Welcome Ephraim. I go to the city and ask them when they cut down tree's to give me a call. Get a load of wood that way. I would think you would be able to find some that way. In Denver they cut and unload it in a lot and you can go get what you want if you ask permission.

For a new turner your stuff looks mighty nice.

[David Klug]

Ephraim the peaces look great. What I would like to know is how you got the center peace nice and round and how you got a nice tight fit on the segmented peaces around it.

DK

[Curt Fuller]

Nice work Ephraim. I also started out doing segmented work. I'm not really sure why I don't do it anymore other than I lost patience for the glue ups when I started collecting 'tree wood'. In a big city like New York they probably have their own Forest Service, several tree trimming services, and who knows what other sources for wood. Start asking around and eventually you have the problem of where you're going to store it all. In the meantime there's nothing wrong with the nice segmented pieces you're doing.

[Gary DeWitt]

Welcome to the group, Ephraim. There's no instant fix for turning wet wood, but there are faster and slower methods of handling it so it doesn't crack still dries faster than it would just left alone. First, most turners will rough out a bowl to about 1" thick for every 10" diameter, let or make it dry, then finish turn. This way, any warpage is turned out of it in the end. This doesn't always apply, especially to natural edge, some bowls are turned wet to finish thickness, allowed to warp, and let that be part of the character of the bowl.
Several methods have been tried to speed drying and reduce cracking (nothing is foolproof) such as alcohol, microwave, boiling, even soaking in dish detergent! Search the group, you'll find threads on them all.
Good luck with your new hobby.

[Ephraim Stern]

What I would like to know is how you got the center peace nice and round and how you got a nice tight fit on the segmented peaces around it.

Hi David,

Right now all i have is a 5" Screw plate so i mounted a piece of 5" x 5" x 8" long piece of hard maple and turrned it to a cone so that it tapers to 3" at the end. For the bottom of the bowl i cut a sloppy round on the band saw and then glue it to the round stockthat is already mounted to the faceplate on the lathe. after it dries i turn it until its just round and then glue the rest of the layers together doing my best to center each one.

i had a lot of trouble getting accurate angle cuts until i got the Incra Miter 5000. i use the Table sled on a 10" table saw with a sharp fine tooth blade. I have found that sometimes my hands move just a little bit which throws off the cut so i use the clamp for every cut i make.

once the cuts are all made i do a dry fit with a belt clamp and make sure that it comes together perfectly. if there are any gaps i find the problem and fix it before i glue them. ( i no longer have joint problems since i got the table sled) - i glue all the pieces at once using rubber bands or a belt clamp.

i hope this answers your questions. if you want i have a link for the plans i used to make my first segmented bowl.

I downloaded detailed instructions online for my first piece and

[Ephraim Stern]

Why not look around in the near by neighborhoods

great idea.. thanks

[Ephraim Stern]

I go to the city and ask them when they cut down tree's to give me a call. Get a load of wood that way. .

another great idea... thanks for the input

[Jim King]

Ephreim: Let me be a bit contrary. I would never think of trying to turn a dry peice of wood. If it is not fresh when I start Iwill not touch it. I turn things for a living and I put my company name on the peices so I have to have the highest quality possible. I will only rough turn fresh wood and boil it prior to drying for stability and speed of drying. My object is to make the wood look naturally like a peice of colored glass. High gloss for me sells . There is no substitue for patience. In my opinion you have to build an inventory of peices in all phases. From fresh cut in the jungle to approx 5% moisture content we need about 5 weeks. Our finished weight of a bowl or whatever averages 7.58% of the weight of the rough cut round blank. The exception to all of the above is if I am making a glue up to turn, in that case only KD lumber 3/4 inch thick or less.

You can see our basic process on our web site http://www.exoticwoodworld.com/index...tic&sc=process (http://www.exoticwoodworld.com/index...tic&sc=process)

[David Klug]

Ephraim please send the link to me. I'm still having trouble understanding how you get segments rounded at the bottom where they glue to the peace that you have turned. e-mail is evad53@yahoo.com

DK