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Bending herringbone purfling
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Author:  Ricardo [ Sun Aug 17, 2008 11:16 am ]
Post subject:  Bending herringbone purfling
Any tips on bending herringbone purfling. Its about .156 wide. I haven't used purfling like this and am concerned how well it will bend. Should it be pre-bent?
Author:  Bruce Dickey [ Sun Aug 17, 2008 1:23 pm ]
Post subject:  Re: Bending herringbone purfling
Ricardo, Everyone seems to bend it in as they install purfling and binding.

I don't though.

I picked this up somewhere, heat some water, like in an old coffee pot. Pour it down a capped PVC tube with the purfling inside. That allows the purfling to become limber. Takes less than ten minutes soaking time.

Using a piece of plywood, I draw out the pattern of the guitar. Remove the limber herringbone, you can test for when it's ready, by pulling it out of the tube.

Patting it dry, I tape it to the plywood board in the precise shape of the guitar. It takes 20 to 30 strips of tape 4 inches or so long. I do cutaway pieces with ready miters too, same way. Works great.

Once taped up I leave it overnight with a small fan on it to dry it completely and use it the next day or so. Good luck. Others do it dry so they say, I've not tried it, just seems too stiff to me. However, after wetting with PVA glue, it may just soften upon application?
Author:  Hesh [ Sun Aug 17, 2008 1:27 pm ]
Post subject:  Re: Bending herringbone purfling
Rich buddy I pre-bent mine in a Fox style bender just like you bend binding taping multiple pieces together and then doing the bend.

There was a good thread about a year ago here where John How explained how he is able to do cut-aways with herringbone using a razor blade to split it first.
Author:  Ricardo [ Sun Aug 17, 2008 2:28 pm ]
Post subject:  Re: Bending herringbone purfling
Thanks Bruce and Hesh. I'll search that topic.
Author:  Allen McFarlen [ Sun Aug 17, 2008 3:07 pm ]
Post subject:  Re: Bending herringbone purfling
I tried the hot water in a tube, and the herringbone purfs that I had delaminated. Then I tried laying out the patten on some MDF with little finishing nails handy. Used a heat gun to warm the purfling up and eased it into shape. Tacked a finishing nail on each side to help hold its shape. Went surprisingly easy.
Author:  Terence Kennedy [ Sun Aug 17, 2008 3:09 pm ]
Post subject:  Re: Bending herringbone purfling
This is the best way I've found.
http://kennedyguitars.com/%20Kennedy%20 ... gbone.html

Terry
Author:  Ricardo [ Sun Aug 17, 2008 3:11 pm ]
Post subject:  Re: Bending herringbone purfling
Thanks you all. Seems like the most challenging part will be doing the cutaway.
Author:  Bobc [ Sun Aug 17, 2008 4:54 pm ]
Post subject:  Re: Bending herringbone purfling
Terence Kennedy wrote:
This is the best way I've found.
http://kennedyguitars.com/%20Kennedy%20 ... gbone.html

Terry

Terry you have a very nice website. Very clean and easy to navigate. Shop looks fantastic too.
BobC
Author:  Terence Kennedy [ Sun Aug 17, 2008 11:28 pm ]
Post subject:  Re: Bending herringbone purfling
Thanks a million Bob, wish I had a wide belt sander like yours.
Terry
Author:  KenH [ Mon Aug 18, 2008 12:53 am ]
Post subject:  Re: Bending herringbone purfling
Bruce Dickey wrote:
Ricardo, Everyone seems to bend it in as they install purfling and binding.

I don't though.

I picked this up somewhere, heat some water, like in an old coffee pot. Pour it down a capped PVC tube with the purfling inside. That allows the purfling to become limber. Takes less than ten minutes soaking time.

Using a piece of plywood, I draw out the pattern of the guitar. Remove the limber herringbone, you can test for when it's ready, by pulling it out of the tube.

Patting it dry, I tape it to the plywood board in the precise shape of the guitar. It takes 20 to 30 strips of tape 4 inches or so long. I do cutaway pieces with ready miters too, same way. Works great.

Once taped up I leave it overnight with a small fan on it to dry it completely and use it the next day or so. Good luck. Others do it dry so they say, I've not tried it, just seems too stiff to me. However, after wetting with PVA glue, it may just soften upon application?



I bent herringbone and rope purflings using this method several times and they came out flawless every time. Somebody posted a toot on it right before the forum crash, but I remembered how it was done and tried it. The only thing I can warn you about is not to leave the purfling in the hot water too long or it will delaminate (voice of experience). I used a template of my cutaway traced out on a piece of poster paper and used push pins on both sides of the purfling to gently hold it in shape while it dried. Perfect fit every time!

The only real advice I can give you is that when you start to make your bends with the purflings, go slow and steady. If you get too excited and try to bend it too fast, it will break the outside band of fibre. Use lots of push pins to hold it all in place until it dries. In my case, that was overnight. The heads on the push pins also help to hold the purfling flat. They tend to want to turn on edge when bent but the push pins worked to end that problem.
Author:  Kirt Myers [ Mon Aug 18, 2008 8:25 am ]
Post subject:  Re: Bending herringbone purfling
I also did the hot water soak in PVC pipe, but I only soaked for 30 seconds. Then I tacked it to my half form to dry overnight. Worked great.

Edit: Here's a couple pics.

Image

Image

Image

Both sides tacked down at same time.
Cheers.
Author:  JJ Donohue [ Mon Aug 18, 2008 8:40 am ]
Post subject:  Re: Bending herringbone purfling
Is it only me, but this stuff has been pretty easy the 2 times I used it on OM's. I actually just relaxed it with heat from a hair dryer and installed it directly to the purf rout on the guitar and taped it in place. Glued it in no time with CA and Bob became my uncle!

I'm glad I didn't know about the soaking procedure or I may have never tried what turned out to be such an easy method.
Author:  Ricardo [ Mon Aug 18, 2008 8:44 am ]
Post subject:  Re: Bending herringbone purfling
Good tips. Anyone bent it around a cutaway (Venetian)?
Author:  Hesh [ Mon Aug 18, 2008 8:48 am ]
Post subject:  Re: Bending herringbone purfling
Rich my friend I just tried to find it and I couldn't but John How provided an excellent explanation as to how he splits herringbone with a razor blade and then does the cut-away. You might want to contact him - he is a super nice guy and one of the best builders too.
Author:  KenH [ Wed Aug 20, 2008 12:31 am ]
Post subject:  Re: Bending herringbone purfling
I used the hot water in a pipe method to bend rope purflings for a cutaway using the method I mentioned above. I think it turned out pretty nice :) I have also done herringbone using the same method.

Attachment:
100_0913 (Medium).jpg
Author:  Bruce Dickey [ Wed Aug 20, 2008 8:19 am ]
Post subject:  Re: Bending herringbone purfling
Image

Terence, I liked your little tuner press following your web link.

So simple, those tools are best, sure beats a hammer and block of wood and it automatically aligns the bore, great.

Those cutaways are the reason I tried the limbering method of a quick swim in hot water. Pre-miter the joint for Florentines and it's a breeze.

I've not tried a Venetian with herringbone. I did learn one thing on this thread. Using a half pattern looks like the way to go.

Martin spoiled me on my first Dred, sending those pre-bent herr.purfs.... So, I pre-bend due to that experience, it was easy to install because it didn't fight back.

Any way you skin the cat that works is good. (hope Don isn't watching)

Ken, that purfling on your guitfiddle looks good. You do the difficult immediately, the impossible takes a little longer.
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