Mimosa light fastness

[Richard Dooling]

Anyone familiar with mimosa as concerns as color shift over time?

It's on a sale at Woodcraft right now. It grows widely (and wildly) in my area but I've never turned it.

Thanks
Richard

[Dennis Ford]

The mimosa that I have turned has not changed color in several years. Pretty wood, turns nicely and is very stable BUT I don't turn it anymore as the dust from sanding it affects me.

[Thomas Canfield]

I will ditto Dennis comments. A dust mask or good vacuum is needed with the local Mimosa. I turned and sanded a simple finial out of local Mimosa today and the dust is an irritant for sure. I do not know how the imported Mimosa that Woodcraft and others handle compare.

[Richard Dooling]

Thanks guys!

I have read about it being an irritant so I'll try it but I'll also take precautions.

[John K Jordan]

Anyone familiar with mimosa as concerns as color shift over time?

It's on a sale at Woodcraft right now. It grows widely (and wildly) in my area but I've never turned it.

Thanks
Richard

From the Wood Database: "Color/Appearance: Color varies from light brown to deeper golden or reddish brown. Sapwood is pale yellow and is demarcated from the heartwood. Color darkens with age." Like most wood! Doesn't say anything about how much or how quickly it darkens.

BTW, I have three plants on my "highly dislike, kill if possible" list since they will take over if permitted: Privet, bush honeysuckle, and mimosa!

Mimosa can indeed be beautiful, though. For example, I found this photo on hobbithouseinc.com:

363469

JKJ

[david privett]

I just finished a 10 inch mimosa crotch bowl ( that just does not sound right) and used 4 coats of Danish oil on it and it turned as dark as walnut , left just a small piece of sap wood in it and it left a nice contrast. But it seemed to me that it has a leaning to have end grain tear out more than I liked. I just cut some more to try with a pen kit.

[Richard Dooling]

John, I had read that the mimosa will darken as you mention but I wonder how much. "Some" is OK but I don't want it to go so dark as to lose all detail. The bowl in your example has great color.

David, I wonder how different finishes influence the look.If you have the time, please post a photo of your piece.

I'll try using some different materials on the scrap and report back in five years . . .

Thanks

[John K Jordan]

John, I had read that the mimosa will darken as you mention but I wonder how much. "Some" is OK but I don't want it to go so dark as to lose all detail.
L
I've heard two theories about darkening - one is that wood darkens with UV light; the other blames it on oxidation. Perhaps a bit of both are the truth but it might be different for different species/colors. I've tested wood before by putting it in the sun light unfinished - some, like cherry, turn a rich darker color. Some people use UV inhibiting finish and claim some success but I haven't seen careful experiments with controls.

I did find certain finishes seem to accelerate darkening at least on some species. For example, I tried Watco "danish" oil on some beautiful cocobolo in in short order the beautiful oranges and reds and browns were gone and the turning looked about as black as ebony! Several other pieces I turned at the same time but finished with shellac were still colorful at the time. (They have turned darker over the last 12 years but nothing like the oiled one.) I haven't repeated this as an experiment but I hope to "someday". I have used TruOil on cocobolo without this darkening but I understand it's not really an oil but a varnish.

Most woods will eventually get darker with age. I'm making things now from large pieces of very old cocobolo which has turned very dark brown, almost black, all the way around the blocks. 1/4" down from the surface the wood is amazing. Since it is dark on all six sides of several different slabs and blocks my guess is the oxygen in the air was a big contributor.

This article addresses color change in exotic woods but the basics should apply to domestics (every wood is exotic to someone!):
http://www.wood-database.com/wood-articles/preventing-color-changes-in-exotic-woods/

Best bet might be like they recommend, seal it the best you can with finish then keep it out of the light as much as possible. I understand preventing deterioration from light is why the light level in museums is often kept low.

JKJ

[Reed Gray]

I have seen huge color variations, mahogany colors to grey and white. I don't care for it for 2 reasons. One it is a very light weight wood and just doesn't 'feel' right, kind of like when you pick it up, it should have more weight to it. The other reason is that I started to react to it.

robo hippy

[Richard Dooling]

I bought a small 2x6x6 piece yesterday that’s honey color. Limited shop time right now partly because it's been very hot and humid. Tidewater Va. in July.

I am just curious about it because mimosa is so common around here. It’s a funny tree that people seem to either like a lot or hate. Many here consider it a nuisance. When I was a kid we had a neighbor who kept cutting out a mimosa that refused to die. Every few years he’d be back at it.

I am probably going to use General Finishes Seal-A-Cell followed with Arm-R-Seal. I’ve been using this combo on maple for about a year on maple with decent results. It imparts some color but it’s not overbearing and not as cold as water-clear finishes can look.

I found this chart that lists it as a fairly strong respiratory irritant but notes elsewhere that it’s rare to have a severe reaction.

http://www.wood-database.com/wood-articles/wood-allergies-and-toxicity/