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03-02-2021, 10:59 AM
(This post was last modified: 03-02-2021, 11:00 AM by DIY GUY.)
Hello Ladies and Gentlemen.
I'm new to the forum, and new to wood working as a hobby. I've carved a few spoons and cut/carved a wood mallet for chiseling. Looking to expand a bit, I picked up a used small wood lathe and am planning to turn my first few projects soon. I've got previous lathe experience with metal and plastic. Watching some online videos, I learned that hard woods are usually better for turning (with sharp tools). Having a Bradford Pear tree i cut down recently, which is supposed to be fairly hard wood, i cut it into sections that will fit in my lathe - about 10" length.
Attached is a picture of this black vein inside the log. Safety is my priority, and I was wondering if this is a problem, or just a unique structure? Thanks very much for any information.
All the best,
Ben
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Welcome to the forum.
Those black lines are called spalting. It is a chemical barrier that fungus colonies produce to keep other colonies from impinging on their territory. From a woodworkers standpoint, it can be a real plus. It often gives spectacular looks to an otherwise boring piece of wood. It is something most of us seek out. The down side is that if spalting is allowed to go on too long, the wood becomes punky and is too soft to work or use.
Rough turn this stuff now and let it dry slowly. The action of the fungus will halt when moisture levels drop below a certain amount. Looks like you have some nice stuff there.
"Mongo only pawn in game of life." Mongo
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Awesome! Thanks clovishound for the information and proper terminology. Is there a technique when it comes to turning with spalting like there is for different grain direction to get smooth cuts? Is it specifically better for say a bowl as opposed to a chalice? Thanks again.
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As long as the wood hasn't gone punky, it turns the same as non spalted wood. Just look out for soft wood.
The lines are a stain, not part of the wood grain. The problem with softening of the wood is that the fungus is slowly eating the wood. It takes a while, but eventually starts getting soft and then eventually falls apart. Early in the process, the wood has seen little damage.
The other issue is that different types of fungus give different stains and patterns. Some give the entire piece a muddy gray color. Not very attractive. Sometimes you get lots of neat, attractive lines, other times just a few lines. You never know for sure what you will get until you start turning it. The cross cuts give a pretty good clue, but you can't be sure what is really inside. The cross cut I see in the picture is encouraging, to me, of a really nicely spalted piece of wood. As long as the muddy gray hasn't taken over a lot of areas, you should have some nice looking wood there.
Check the hardness with your fingernail on the ends. If you can easily dig out wood with your fingernail, it's probably a lost cause.
"Mongo only pawn in game of life." Mongo
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Welcome to Woodnet.
You already have some good advice above.
To that, some basics that I would add:
- even in its early stages, spalted areas are softer than unspalted areas and will be removed faster when sanding.
- spalting can give very nice patterns to our turnings, but it can also produce fungal infections in our lungs. You want to minimize the amount of the dust that you inhale from the active fungus. That practice of dust control will also help you avoid sensitizing to the woods that can cause allergic reactions.
- in general, you should remove the pith before you start turning a blank (lots of exceptions to that rule, but they _are_ exceptions). Otherwise, the differential shrinking of the wood will cause splitting. It looks like you already have a small split forming at about the 5 o'clock position in the pic.
I highly recommend that you download Wood Handbook, Wood as an Engineering Material from the United States Department of Agriculture Forest Products Laboratory.
Chapter 13 is especially important for turners since we often start with green wood.
For wood sensitivities, good places to start are:
The Wood Database
Woodcraft
"the most important safety feature on any tool is the one between your ears." - Ken Vick
A wish for you all: May you keep buying green bananas.
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Welcome to the group and the Wonderful World of Woodturning. If you have any other tools in your shop other than perhaps a bandsaw, get rid of them. They just take up valuable space and you will never use them again. Oh, if you have a table saw, that flat surface is good for storing stuff.
Find a turner's club near you. There are many. Your profile doesn't say where you are located, or we could find one for you. Those clubs are valuable sources of information and often, very good deals on tools. Turners as a rule are very willing to share techniques and perhaps can help you avoid rookie mistakes.
GM
The only tool I have is a lathe. Everything else is an accessory.
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(03-03-2021, 07:20 AM)Grey Mountain Wrote: Welcome to the group and the Wonderful World of Woodturning. If you have any other tools in your shop other than perhaps a bandsaw, get rid of them. They just take up valuable space and you will never use them again. Oh, if you have a table saw, that flat surface is good for storing stuff.
GM
Have you been looking in my shop?
"Mongo only pawn in game of life." Mongo
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Thanks very much everyone for the useful information. My little lathe can hold up to 12" long and 4" diameter. When I split these logs, I'll try to pay attention to any existing splits like you mentioned iclark, and can hopefully keep them out of the pieces I'll be working. A band saw would be super useful, and maybe i can find a used one that is not too big. Used to have access to one in the shop at my workplace, but COVID shut that down. In the mean time, I'm thinking to drill a few holes to help the wood split where i want and then use my miter saw (45-degree cuts with the piece laying on a flat side) to help cut the excess to a good starting fit, maybe octagonal shape-as symmetric as I can manage.
I'm in Detroit, MI Grey Mountain. Had a laugh about the table saw (though I do use mine). Sounds like the elliptical I have. A friend gave me the best advice. Buy the elliptical with the most arms - you can hang the most coats on it lol.
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(03-03-2021, 09:38 AM)DIY GUY Wrote: Had a laugh about the table saw (though I do use mine).
Not any more, you won't. Just remember Keith Fenner's famous quote "There's no such thing as an empty flat spot."
We do segmented turning, not because it is easy, but because it is hard.
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(03-03-2021, 09:38 AM)DIY GUY Wrote: My little lathe can hold up to 12" long and 4" diameter.
I would think that is 8" diameter. Most lathes list swing as diameter rather than radius. The common mini lathes are usually 10" swing. That would be 5" between the bed and the center of the spindle.
If you get into turning, you will quickly want something bigger. And then you will need a chainsaw, then a bandsaw, not to mention the trunkload of gouges and parting tools, skews, hollowing tools, etc, etc.
Uh, you do have a grinder don't you?
"Mongo only pawn in game of life." Mongo
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