Purple heart in the oven

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Sfolivier

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I always seems to post questions... So I wanted to post a trick instead this time :) When turning purpleheart, try to make it change color in your oven. I just placed segments of a gelwriter in mine and it was very interesting. The color had a blue / red gradient within the blank and was overall much more intense and violet (instead of purple) than what I had been able to achieve before.

Here are my thoughts:

- 250oF, 10 minutes. Monitor the barrels all the time. The wood will turn purple, then violet, then black if grossly overdone.

- It's okay to put the mandrel with the unfinished barrels in the oven. Just loosen the end nut to allow for expansion.

- It's metal above water boiling temperature. Use protection when handling the mandrel. It will take a while to cool too.

- Use a collection pan (either made of aluminum foil or a cheap disposable one). If you overdo the blank it may leak some smelly stuff you don't want to keep in the oven.

- Rotate the blank... Or not for interesting effects... The temperature will probably not be homogeneous.

have fun!

PS: I wish I had taken a picture before giving the pen to a friend [8)]
 
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Once the color has changed, I don't think it behaves any differently from a standard purpleheart tint. It's just a different way to convert pigments. I bet UV will affect it, although I don't know how since the shade is slightly unusual (violet instead of purple). Hopefully it won't be too much of a problem for our pens... I finished the last pen with a simple friction polish (shellac) and it's been fine for a few weeks.
 
Originally posted by R2

You learn something every day! how long does the colour last? Does UV effect it?
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Yes, UV does affect PH. Lots of archived posts on this subject with purple heart as well as some other woods too, including padauk. I don't remember if heat has any affect on padauk like it does PH.
 
Check this out:

' An Investigation of the Factors controlling the Color Change of Purpleheart Wood'
http://www.organicsculpture.com/Purpleheart.html

An easier way to do this is to stabilize purple heart. It undergoes the same heat treatment during the process and turns out quite nice looking.



IMG_4009.JPG


This block was stabilized by WSSI and has yet to do any form of color changes. It shows the blues quite well.

Ed
 
It makes sense. A lot of stabilizing polymers are thermally cured. It's just fun to do it yourself tho, and it allows from some gradient effect. The color seems right tho, my last blanks were really like the blueish area.
 
I did the oven method. Here are before and after scans (after is on the right).

Fifteen minutes at 350 degrees:
purpleheart.jpg


and anotehr ten minutes at 350 degrees:
purpleheart2.jpg
 
Ed,

I read the whole piece to which you included a link. It seems to espouse heat-treatment but it doesn't say in what manner the heat was applied. You're seeming to espouse some different method - stabilization - which you indicate is easier but about which I have no knowledge. Can you explain how one goes about stabilizing wood and why or how this is easier than sticking the piece of wood in the oven for ten minutes?

By stabilizing I'm assuming you mean the same process by which some commercial operators infuse soft or punky wood with plastics so that the wood is more easily and uniformly cut. Since purpleheart is so hard, stabilizing for this reason seems pointless. Besides which, its hardness would seem to me to inhibit the stabilization proces by limiting how much of the plastic would get into the wood. I think all you really get from it is the heat.

And again I say - ten minutes in the oven at 350 degrees and you're done. Easy as can be.

Maybe even easier - use a heat gun and apply after turning, while the pen planks are still on the lathe, so you can watch until you get just the right purple color.

I've done that method too.

Just my thoughts. Looing forward to reading yours.

Julia
 
Originally posted by edstreet

You can also use feed-n-wax to bring out the color instantly before adding the ca finish :)
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Have you actually used a CA finish over Feed-n-Wax? It seem counter-intuitive to put CA over beeswax and carnauba wax.
 
Julia ... I have found that professional stabilization of purple heart renders the wood to be even harder than normal, the wood takes to the tool even better - meaning it is easier and 'cleaner' to cut, but the best thing is than oils from one's hand does not change the wood at all. It stays cleaner, is water proofed beyond one's imagination, refuses to get dirty, etc.

All around I believe that any wood that is a candidate for the professional stabilization process gives us the wood worker a much more easier piece of wood to work with in every aspect of the wood working task. I much prefer the stabilized wood over non-stabilized wood. Some here and in the 'customer field will often say the wood is too plastic looking/feeling. My reply is 'to each his own.' If the customer doesn't like the process don't use stabilization on their wood.

WSSI is indeed one excellent source for having your wood stabilized. They have an over abundance of knowledge of how woods will react to the process and will tell you right up front if the wood cannot be stabilized. Call them with any questions you have and I guarantee you that you will never be mislead.

BTW, WSSI and others prefer the wood to be stabilized to be less than 10% moisture content. In other words NOT GREEN wood as the moisture is not acceptable to the process. :D
 
I read a blog on a pen turners web site, which I do not have stored on this computer, which mentioned burnishing on the lathe to bring out what he called a "grape jelly" color.

I tried it using a cork block from ROCKLER. I held it on the blank as it was spinning and as it heated the wood up it started to turn different shades of purple. When I got it to the "grape jelly" color I stop applying pressure.

I finished it with HUT Crystal Coat and when I gave it away to a friend who like purple it was still the dark purpler color.

I read somewhere that if you place PH in the sun it will get darker as well. The only catch in doing that is that if left to long it will turn brown. Rosewood will do the same thing if left in the sun.

Paduak, Pick Ivory, Redheart and other woods will turn brown as well due to the sun.

However, one item I read said to use the protective wipe, like AmourAll or MacGuires, will prevent the color change if used periodically just like the way that they protect the dash board and other components in your car. They do this by providing a UV inhibitors. TonyL talks about REJEX in his post on how he polishes his acrylic pen blanks.
 
Hello Elwin

This is a rather old thread but I can say the same ideas are there. All woods change color. Rosewood will darken but not lose its color. Colored woods such as you mention will darken and then eventually turn brown in due time. Heat and UV plays a large roll in that and yes you can control to a certain extent. You can finish with a UV prohibiting finish. You can avoid direct sunlight and heat. Some woods actually take on a better look when they age and some woods just lose their appeal all together. I have 2 pieces of pink ivory sitting on my workbench. Both bought the same time. Both were as pink as a flower when I bought them. One has turned a tan and the other is still as pink as the day I bought it. Just from sitting in the air and no finish on it.

But the thing that gets overlooked many times is every piece of wood is not the same and by that I mean just because it comes from the same family it may have more resin or tannins in it thus making it more impervious to color change. That is why some purple heart is true purple for a lot longer time. I have many examples of that in my shop from various woods. Redheart is another one of those love it or hate it. I have found yellow heart to be one that stays yellow in all conditions and does not change color much at all. Now this is true yellowheart. There are other woods that are yellow in color but do not follow this pattern.

Good luck when using mother nature's colored woods.
 
I just completed a cutting board with maple and purpleheart. When completed, the purpleheart was brown. I remembered light helps so I put it in the sun for about 20 minutes flipping it over at ten. It turned purple. After Howard's Butcher Block Finish it looked wonderful.

Try sunlight!
 
Purpleheart is deep purple and beautiful

Here is a quick photo from a phone. The ribbon is used to hold item information, care instructions and the price. Better in person.

DF9C9EE9-8DF1-46C9-8B3F-AE1A2F58EC1B_zpsld6b0kvh.jpg


It was brown like walnut/cherry mixed together before sun treatment. I've used this a few times and seen it happen often to fishing lures trolled in the sun behind the boat. The purpleheart gets more purple, for a while... Everything colorful goes brown after time.
 
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That is a beautiful cutting board. It looks amazing. I love what happened with the purple heart after a little time in the sun.
 
I use a sanding block made of cork and burnish on the lathe while it is spinning. You can control the shade that you get by the amount of pressure and time spent. I have had it turn violet and the same color as grape jelly.
 
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