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Bending Curly Narra
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=47052		 Page 1 of 1
Author:  fingerstyle1978 [ Wed Jan 13, 2016 7:37 pm ]
Post subject:  Bending Curly Narra
Any tips? I've not bent any Padauk/Narra and as far as figured wood, just bindings and some heavily quilted maple sides that came out wavy. They are currently at a thickness of 0.095". If I keep thinning to 0.076" am I more likely to have waves in the side or less? I am going to laminate these sides as there is a small crack in the grain. I thought about doing a cutaway to avoid breaking the side as it falls in the upper bout bend. I hadn't noticed it until I started inspecting after sanding.

Also what temps work best? Is less water better to avoid ripples?

Image


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Author:  fingerstyle1978 [ Fri Jan 15, 2016 8:45 pm ]
Post subject:  Re: Bending Curly Narra
Bueller....Bueller....anyone???
Author:  Michaeldc [ Sat Jan 16, 2016 1:16 am ]
Post subject:  Re: Bending Curly Narra
Joey,

I've bent Padauk several time with flawless results. In fact I just bent a set for a 00 cutaway a couple of days ago. Is narra technically the same thing only a different color?
Author:  fingerstyle1978 [ Sat Jan 16, 2016 10:03 am ]
Post subject:  Re: Bending Curly Narra
Michaeldc wrote:
Joey,

I've bent Padauk several time with flawless results. In fact I just bent a set for a 00 cutaway a couple of days ago. Is narra technically the same thing only a different color?


Technically yes, Padauk refers to all woods of the Pterocarpus genus and Narra is Pterocarpus Indicus. The color in the photo is off. It's more red than that, especially under finish.
Author:  Mike OMelia [ Sat Jan 16, 2016 10:04 am ]
Post subject:  Re: Bending Curly Narra
Where did u buy that set? Most reputable dealers will replace that cracked side. Use SSII
Author:  fingerstyle1978 [ Sat Jan 16, 2016 11:25 am ]
Post subject:  Re: Bending Curly Narra
Mike O'Melia wrote:
Where did u buy that set? Most reputable dealers will replace that cracked side. Use SSII


It was an auction during a Swapalooza here from Bob Cef about 4-5 years ago.
Author:  fingerstyle1978 [ Sun May 01, 2016 10:17 am ]
Post subject:  Re: Bending Curly Narra
Just finished up a large fruit and vegetable garden and built a new workbench. I'm finally able to get back to this but the sides did come out wavy. The sides are still a decent thickness. What's the best way to deal with wavy sides? I was thinking about putting them in the bender again hoping that some of the waves settle a bit after its sat for several months bow, hitting them with a cabinet scraper and then laminating then to mahogany or walnut.
Author:  Colin North [ Sun May 01, 2016 3:00 pm ]
Post subject:  Re: Bending Curly Narra
Less water is better with figured sides, but sometimes leads to spring back a bit more than normal.
Suggestion?
I would try a wipe with SS II, put them back in the bender with a slightly damp (not wet) paper top and bottom, slats on firmly and reheat to 320F/5mins then drop back to 265F/15 minutes and cool. (I used two spring steel slats underneath rather than one to give better support, but don't know your setup)
Then repeat the cycle again twice, just going to 320F and then dropping back to 265F for 10 mins, cooling between to around room temperature.
Helped with a cupped/wavy set I had - made it useable, and might save you laminating the sides.
Author:  fingerstyle1978 [ Mon May 02, 2016 7:45 pm ]
Post subject:  Re: Bending Curly Narra
Colin North wrote:
Less water is better with figured sides, but sometimes leads to spring back a bit more than normal.
Suggestion?
I would try a wipe with SS II, put them back in the bender with a slightly damp (not wet) paper top and bottom, slats on firmly and reheat to 320F/5mins then drop back to 265F/15 minutes and cool. (I used two spring steel slats underneath rather than one to give better support, but don't know your setup)
Then repeat the cycle again twice, just going to 320F and then dropping back to 265F for 10 mins, cooling between to around room temperature.
Helped with a cupped/wavy set I had - made it useable, and might save you laminating the sides.


Thanks, I've put off the SS 2 purchase too long. I went ahead and ordered it. I'll post pics of the results. Plus I have a bunch of Ebony that i've been too worried about bending that it should help with as well.
Author:  Mike OMelia [ Tue May 03, 2016 8:20 am ]
Post subject:  Re: Bending Curly Narra
After bent, fill with epoxy. Put tape on other side. And along crack edge to minimize exposure. Should be fine.
Author:  Colin North [ Tue May 03, 2016 9:10 am ]
Post subject:  Re: Bending Curly Narra
Maybe with end grain sanding dust (very fine) in the glue.
If you work the dust in first, thin CA may work too, it looks like a very a very fine crack.
Masking it off is a good idea.
Author:  Mike OMelia [ Tue May 03, 2016 10:16 pm ]
Post subject:  Re: Bending Curly Narra
Right. Never wait for the adhesive to fully set in these situations. Partial set. The hit with ROS. Grinds dust into partially set adhesive. Excellent blending. Ido this on rosettes all the time.
Author:  fingerstyle1978 [ Sat May 28, 2016 1:11 pm ]
Post subject:  Re: Bending Curly Narra
Colin North wrote:
Less water is better with figured sides, but sometimes leads to spring back a bit more than normal.
Suggestion?
I would try a wipe with SS II, put them back in the bender with a slightly damp (not wet) paper top and bottom, slats on firmly and reheat to 320F/5mins then drop back to 265F/15 minutes and cool. (I used two spring steel slats underneath rather than one to give better support, but don't know your setup)
Then repeat the cycle again twice, just going to 320F and then dropping back to 265F for 10 mins, cooling between to around room temperature.
Helped with a cupped/wavy set I had - made it useable, and might save you laminating the sides.


Do you wait for the SS to dry or do it while wet?
Author:  Colin North [ Sat May 28, 2016 1:33 pm ]
Post subject:  Re: Bending Curly Narra
I would give it a good wipe and wait 10 minutes to allow it to soak into the wood and dry off. Doesn't have to be bone dry.
(It's quite volatile)
Author:  fingerstyle1978 [ Mon May 30, 2016 3:01 pm ]
Post subject:  Re: TFIG OLF GIVAWAY! From ALLIED LUTHERIE!
Well that didn't exactly go as planned but it did help. The SSII leached and the wood scorched a bit but I was able to fill all the cracks and level the waves that were left with a RO Sander and a cabinet scraper pretty quickly. Thanks for the advice.

Image
Image

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Author:  Joe Beaver [ Mon May 30, 2016 3:21 pm ]
Post subject:  Re: Bending Curly Narra
Good recovery
Author:  fingerstyle1978 [ Mon May 30, 2016 7:16 pm ]
Post subject:  Re: Bending Curly Narra
Joe Beaver wrote:
Good recovery

Thanks. I've got to get better with figured woods. The last set I dealt with was quilted maple. I managed to save that set too but I'm getting ready to bend some Malaysian ebony that has large curl. Debating on bending dry after SSII or light misted water and foil. I really don't wanna screw that set up. It's one of my nicest sets.

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Author:  Joe Beaver [ Mon May 30, 2016 7:55 pm ]
Post subject:  Re: Bending Curly Narra
I've used SSII a few times, it does seem to help. The down side is it takes a little of the color out, but after scraping and sanding and all the things we do to the sides it is hard to notice.

What temperature do you bend at? Use a heat prob?
Author:  fingerstyle1978 [ Mon May 30, 2016 8:52 pm ]
Post subject:  Re: Bending Curly Narra
Joe Beaver wrote:
I've used SSII a few times, it does seem to help. The down side is it takes a little of the color out, but after scraping and sanding and all the things we do to the sides it is hard to notice.

What temperature do you bend at? Use a heat prob?


I usually try to start at 210 using a fox style bending jig. Ebony and figured woods I have been letting get a bit hotter ~270-290 to start the lower bout. I've actually been putting off buying a new digital probe for some reason. I've been using a kitchen probe thermometer that only shows to 200 degrees but continues going up. I've been kind of guessing and trying to use feel more. Everything I'm building with right now are my cheap sets except the Malaysian Ebony. I'm going to go ahead and order a new probe thermometer right now!
Author:  Colin North [ Tue May 31, 2016 2:22 am ]
Post subject:  Re: Bending Curly Narra
fingerstyle1978 wrote:
Joe Beaver wrote:
I've used SSII a few times, it does seem to help. The down side is it takes a little of the color out, but after scraping and sanding and all the things we do to the sides it is hard to notice.

What temperature do you bend at? Use a heat prob?


I usually try to start at 210 using a fox style bending jig. Ebony and figured woods I have been letting get a bit hotter ~270-290 to start the lower bout. I've actually been putting off buying a new digital probe for some reason. I've been using a kitchen probe thermometer that only shows to 200 degrees but continues going up. I've been kind of guessing and trying to use feel more. Everything I'm building with right now are my cheap sets except the Malaysian Ebony. I'm going to go ahead and order a new probe thermometer right now!

Just a hint - http://www.luthiersforum.com/forum/viewtopic.php?f=10117&t=47715
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