Back to turning,plus a question

[Harry Robinette]

Well I'm back to turning sort of,:) I finished a 14" maple bowl thats been in the shop for a while.Put a final coat of wax on and finished the bottom using the vacuum chuck. It's just some Ambrosia Maple 14"dia. and about 3/8 thick fruit bowl basically.Now for the question I get this discoloration with almost all the Maple I turn and have tried everything to keep it from happening You can see it all around the bottom edge about 2 1/2" up from the bottom,some times it's right in the middle or a spot on the top it's about to drive me nuts.
It happens when ever I turn maple of any kind and any shape I get this mark that looks like its dirty.:confused:pic 4
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[Michael James]

Very nice bowl and a great looking finish on it! Sorry, no help on your question.
mj

[Bob Bergstrom]

Looks like a nice user. Well made and sure make someone really happy they know you well.

[Baxter Smith]

Nicel bowls. I get what looks like the same thing Harry so will be interested in hearing the answers as well. I haven't been turning long enough to see if the colors on the affected bowls even out with time.

[John Hart]

It really just looks like the staining that is typical with soft maples...which is why the ambrosia beetle leaves such a stunning display. Most of my soft maples have some form of random stains throughout as well. I could be wrong, but from here, that's what it looks like.

[Bill Blasic]

Ditto what John said.
Bill

[Fred Belknap]

There is a lot of different maple trees. I have some with the black/grey streaks. My guess is that it is the type or maybe the soil it grew in. There are hard, soft, sugar, big leaf,curly,birds eye,etc. I think even box elder is a type of maple.

[Dale Miner]

The stain that I see is caused by a fungus that grows in the wood during the drying phase. I too had trouble with the staining. It would aggrvate me to have a piece of maple that was nearly pure white, great contrast between the wood and the ambrosia streaks, only to find after drying that the grey stain had muddied the wood in a way that I found unattractive. I would occasionally get the same grey on ash, box elder, and other light colored woods. I tried washing the roughouts with houshold bleach to kill the spores, but that only made it worse. Eventually, I started washing the roughouts with boric acid disolved in water. I wrote a 'Tip' for the American Woodturner's Tips and Tricks section with my explanation of the how and why of the failure of the bleach and reason for the boric acid. Briefly, bleach is mostly water, the chlorine leaves the wood in a day or two and the water from the bleach remains, promoting mold growth. The boric acid wash also introduces water, but the boric acid does not leave the wood, and remains as a toxin to fungal growth. You may want to read up on the health concerns of boric acid before using it.

Since using the boric acid washdown on white colored woods, I can't recall having had any bowls develop the grey staining. If I roughout woods that are susceptible to the staining in cold weather, I bag them and put them in an unheated outbuilding. The mold can not grow when temps are below about 42 F.

Later,
Dale Miner

[John Hart]

That's really cool Dale. I have tons of boric acid.(I use it to feed to ants so they carry it back to their children to kill them ;))

I think I'll give that a shot!!

[Harry Robinette]

Dale
Thanks allot I never heard that with the boric acid.Oh ya it has been driving me nuts so you know I'm going to try it.

[Jeff Nicol]

The trouble with the maples is that if they are cut and turned while they still have some sap in them they will get the streaks in them. If you cut them when it is cold the mold won't grow, so when I saw maple I do it in the early spring before the sap is in the tree or in the late fall/winter and get it stacked and stickered so it will begin to dry fast to deter the stains. The Red maple is probably the worst for the streaks, so when you rough turn it get it sealed as quick as possible to keep the air from the fresh wood. The dark streaks are ambrosia and you can see the bug hole in the one picture near the rim.

I guess that is why all of the maples will spalt pretty easily due to the sugars or something in the sap that the fungus and molds can attack at will!

They just add character,

Jeff