Is Purpleheart hard to work?

[Frederick Skelly]

Hi guys,.
I'm making a small marking gauge along the line of the Hamilton Toolworks 4" gauge. I'm using Purpleheart and brass. Should be pretty and work well if I can get it finished. Right now I'm frustrated.

Is this stuff brittle or is it just me? I had the "arm" fabricated and drilled a small hole in the end to match the size of the screw I'm using to hold the blade. When I screwed in the screw, it split the part right down the middle. Never had this happen in maple and I was surprised to see it here. The arm is 1/4" thick, 3/4" wide and 4" long. It has a 3" long slot down the middle.

Then, when I glued the 2 halves back together, the glue wouldn't hold. I've never seen wood the titebond would't bond. I let it sit 2 hrs - it just fell into 2 halves again. It's as if the wood is so dense the glue wouldn't penetrate.

I was also surprised the my normal files hardly make a dent in this stuff.

Anyone familiar with this wood and can offer advice on how to work it?

Thank you!
Fred

[Phil Mueller]

Sorry to hear. It's a beautiful wood, I use from time to time. In addition to being relatively hard, it's also quite brittle. Splitting can be a common thing. I tend to drill a larger pilot hole than usual and only use a hand held screwdriver. If I feel too much resistence with a screw, I back it out and drill the hold larger.

It's moderately tough on cutting tools...hand and power. Due to it's resin content, power tools can leave burn marks if not careful. Burn marks are almost impossible to get out.

I haven't had the glue up problem you experienced. The resin content may have prevented good adhesion. Maybe it needed to be freshly sanded some before gluing.

I find some pieces are great to work...others are a bear.

And it splinters like crazy. I always wear gloves. I've spent more time than I care to remember pulling nasty splinters from my hands.

Good luck!

[Jim Koepke]

Purple heart has also been pretty splintery for me. I did have some luck turning.

Some woods with a lot of resin or oil need to be 'degreased' before glue will hold. This can be done by cleaning with lacquer thinner or acetone. I have done this when gluing rosewood totes back together.

jtk

[Frederick Skelly]

Phil, Jim,
Thanks for the insights and ideas. I'll do as you both suggest. It really is beautiful wood. It's worth the extra effort. I keep thinking of that workbench made of Purpleheart that Winton Applegate made and posted here a couple years ago - gorgeous, but now I understand that it must've been a real bear to build!

Best regards,
Fred

[Mike Null]

I'm with all those who complain about splintering. It is the worst wood I've ever used in that respect. Still, I like the color and the grain.

[brian zawatsky]

Maybe it was just the grain in the particular pieces of stock that I had to work with, but the grain seemed to change direction frequently and kind of appear to be interlocked in places. Made it a real pain to work with a hand plane. Tear out and splintering were definitely issues.

Very pretty wood when finished though, and contrary to popular belief I've found that it holds its purple color for a long time if it's not in direct sunlight. I have a small keepsake box that I made about 5 years ago of PH and it's still as vibrant purple as the day I finished it.

[John K Jordan]

Very pretty wood when finished though, and contrary to popular belief I've found that it holds its purple color for a long time if it's not in direct sunlight. I have a small keepsake box that I made about 5 years ago of PH and it's still as vibrant purple as the day I finished it.

I haven't worked it with hand tools but I have turned a bunch of purple heart. Three things about the color I have found - sealing it well will prolong the color. Keeping it out of the sun will help.

The third thing: there is purple heart and there is purple heart. Most that I've had is brown when cut then develops the purple color after exposure to light, it seems, and air. For this, I turn it, let it change to purple, then apply sealer and finish. However, I have some that is very, very purple immediately when cut. This "variety" appears to hold it's color much better. I am real careful with what I have left of this.

It is brittle and splintery but no problem with sharp turning tools.

BTW, about color change: http://www.wood-database.com/wood-articles/preventing-color-changes-in-exotic-woods/

BTW2, an acquaintance from South America who deals in wood said once he couldn't understand our fascination with purple heart. Where he comes from they use it for floor joists, cheap flooring, etc. The most sought after wood in his area for cabinets, walls? Knotty pine!

JKJ

[Phil Mueller]

Funny you should say that, John...someone told me it's so common down there they use it for pallets.

[nima hadavi]

Yes it does splinter, a lot. I have used it many a times to build semi hollow body guitar tops and found that razor sharp tooling with constant honing (I keep my stone on the bench when working prurpleheart) is the ticket.

Also I am religious about giving a quick a sand and wipe down with acetone before glue ups. Never had issues this way.

Good luck, the end results are beautiful!

337824

[george wilson]

You can de grease the wood before gluing,but epoxy might hold better than regular glues which are water based.

[Brian Holcombe]

Funny you should say that, John...someone told me it's so common down there they use it for pallets.

I was having a conversation with a fellow at my local lumberyard and we were on the topic of purple heart (they're doing a big project in it), turns out they also use it for timber frame when it's green.

I'd imagine it's more fun to carve rock, but it's impressive that they utilize this lumber in that way.

[Frederick Skelly]

Thanks for all the tips guys! I got it done today and I just put the third coat of shellac on it. I had to remake the arm 3 times - it just kept breaking. So I'm a little skeptical that the one I'm using will hold up. But it's pretty and it works well. I'll post some pics when she's dry.

Thanks again.
Fred

[george wilson]

The trouble is,you already have water based glue in the wood fibers,and you are just gluing on over the glue that failed.

[Frederick Skelly]

The trouble is,you already have water based glue in the wood fibers,and you are just gluing on over the glue that failed.

No Sir, I wasn't clear. I remade the part from scratch, two more times after my foolish attempt to glue the first one failed. I broke the second one because this stuff is fairly brittle sand I clamped it too tight when drilling a srew hole. The third one seems just fine. :)

[Mike Holbrook]

Just went and found a few off cuts from purple heart planes I made from Steve Knight kits. I am thinking about making a straight edge or winding sticks. The pieces are 2/32-5/32" thick x 2" x 26". They have been in my basement for several years. Steve was right, very stable wood, which is why he suggested it for plane bodies. None of the off cuts has any sort of crack, twist, cup, bow or any other kind of change that I can see.