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Bracing A Back (Pics)
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Author:  Hesh [ Sun Feb 24, 2008 7:04 pm ]
Post subject:  Re: Bracing A Back (Pics)
No typo Sister Lillian the 25' radius stick is mashed completely flat with the back placed on a clean flat surface and not in a dish. I never thought that a BJR in and of itself contributes to the holding the radius of a back any way. So the purpose of the stick, radiused, is to apply even clamping pressure along the entire length of the BJR when placed on a flat surface. And, only two cam clamps are required.

In addition, for those that like to use a straight edge to butt the BJR against on one side it's easier to use the straight on a flat surface then trying to press in into a radius dish.
Author:  Lillian F-W [ Sun Feb 24, 2008 7:14 pm ]
Post subject:  Re: Bracing A Back (Pics)
Thanks Hesh.
Author:  ChuckH [ Sun Feb 24, 2008 8:32 pm ]
Post subject:  Re: Bracing A Back (Pics)
Hesh wrote:
No typo Sister Lillian the 25' radius stick is mashed completely flat with the back placed on a clean flat surface and not in a dish. I never thought that a BJR in and of itself contributes to the holding the radius of a back any way. So the purpose of the stick, radiused, is to apply even clamping pressure along the entire length of the BJR when placed on a flat surface. And, only two cam clamps are required.

In addition, for those that like to use a straight edge to butt the BJR against on one side it's easier to use the straight on a flat surface then trying to press in into a radius dish.


An originally ingenious conception of execution!.....as I was viewing the pictures of your clever contraption, I thunk to myself, "How dat holding a 25' radius using a flat board underneath?".........Ah, the curvature bends and clamps the whole length of the back strip down tight. I laid the wide metal rule on top when I clamped her down and remember thinking that I wouldn't be able to see if the bjr might have slid a bit off the center line. It also made it harder to clean up the hhg sqeeze out.
Beautiful Hesh, just beautiful stuff here to be learnt.
Couple other questions....what jig are you referring to concerning the bjr and where might one acquire such an item? Also...you mentioned taping a piece of plastic over your label during installation of the back. Is that so you won't stain it with glue during the proceedure and I assume the plastic will be removed at some point?
Author:  Hesh [ Sun Feb 24, 2008 9:18 pm ]
Post subject:  Re: Bracing A Back (Pics)
Chuck here are some more pics that may help here.

First the covered label is to protect it during finish and just generally keeps it cleaner until I am ready to string it up. It's a cut up baggie with low-tack blue painters tape. It's also a lot easier to install the label prior to installing the back on the rim.

Attachment:
DSC01312.jpg


Here is the stick that I use to clamp down the BJR on a flat surface. I think that this idea came from Stew-Mac and their free-for-download d*ead kit instructions. It's radiused to 25' on the bottom, 1/2" wide when the back strip is 3/4" wide so clean up access for squeeze-out is a breeze, and 3/4" high poplar.

Attachment:
DSC01314.jpg


Attachment:
DSC01315.jpg


And when you clamp down both ends it of course applies clamping pressure over it's entire length.

Attachment:
DSC01316.jpg


I hope this helps.
Author:  Lillian F-W [ Sun Feb 24, 2008 9:36 pm ]
Post subject:  Re: Bracing A Back (Pics)
Doh! Now I understand you what you are doing. You aren't trying to clamp it to the radius, but using the curvature to make sure that you have even pressure on the joint.
Thanks Hesh.
Author:  Hesh [ Sun Feb 24, 2008 9:41 pm ]
Post subject:  Re: Bracing A Back (Pics)
You got it Lillian [:Y:]

Don't laugh but this is the only jig that I ever made myself..... s stinkin stick......... :o :lol:
Author:  KenH [ Sun Feb 24, 2008 10:40 pm ]
Post subject:  Re: Bracing A Back (Pics)
Excellent pictorial Hesh!

If it means anything, I do this the same way. It is good to share little tips like this with others that are beginning the trade so that they dont overlook the small details.

I actually learned the "curved stick" trick from Frank Finoccio, and it works well to get good adhesion and coverage down the entire strip of the back strap.

On a side note, Somehow I managed to build one guitar that I completely forgot to put the backstrap in. I didnt even notice the missing piece until the guitar was completely sealed up. I'll have to wait and see how that one holds up.
Author:  Steve Kinnaird [ Sun Feb 24, 2008 11:00 pm ]
Post subject:  Re: Bracing A Back (Pics)
As clean as usual, Hesh.
But the pic with the gloved hand gave me a real laugh!
(Then I read the caption, and thought, "Maybe he's on to something here...")
Good work amigo.

Steve
Author:  WaddyThomson [ Mon Feb 25, 2008 12:53 am ]
Post subject:  Re: Bracing A Back (Pics)
Great tutorial Hesh, as per usual. [clap] [clap] [clap]
Author:  BruceHerrmann [ Tue Feb 26, 2008 1:36 pm ]
Post subject:  Re: Bracing A Back (Pics)
I caught that gloved hand as well, I always wear nitrile gloves, especially when french polishing and many other times as well. Saves a lot of work getting glue etc. out of the fingernails. I'm concerned about latex as it reacts with so many materials that I stick with nitrile.

And yes, I felt like the karate kid just worked me over after that french polishing job on the Dread, but wait, there's more. I glued the neck on, body all polished and looking great, taped a small area on the back adjacent to the heel where sometimes a little glue will run out during the clamping process and it protects the back (or is supposed to). Of course, no glue came out this time and I carefully removed the low-tac tape only to pull off some of the shellac. Rats. Now I'm busy repairing that area, it will be fine, just one more job I didn't need.

Do you guys find that when shaving Adirondack braces to final form, using a small finger plane like Hesh uses, that you get some unwanted chips or gouges due to the hardness of the spruce? It's the one thing I've noticed since switching from Sitka to Adirondack for bracing. Maybe it's my technique, or lack thereof, that's causing the problem. I just find I have to be very careful about grain direction, much more so than with Sitka.

Thanks again Hesh, great job.

Bruce
Author:  Hesh [ Tue Feb 26, 2008 1:49 pm ]
Post subject:  Re: Bracing A Back (Pics)
BruceHerrmann wrote:

Do you guys find that when shaving Adirondack braces to final form, using a small finger plane like Hesh uses, that you get some unwanted chips or gouges due to the hardness of the spruce? It's the one thing I've noticed since switching from Sitka to Adirondack for bracing. Maybe it's my technique, or lack thereof, that's causing the problem. I just find I have to be very careful about grain direction, much more so than with Sitka.


Bruce


Bruce buddy I try to sharpen my planes and the few chisels that I always use when building every 2 guitars. My experience has been that my finger planes chip and gouge when they are no longer super sharp. This being the second guitar since I sharpened them I had some chipping and a bit of gouging too so it's time to do some sharpening.

Many thanks everyone!!! :)
Author:  JJ Donohue [ Tue Feb 26, 2008 4:46 pm ]
Post subject:  Re: Bracing A Back (Pics)
Gouging and chipout could very well indicate the need to sharpen. It could also simply mean that the wood wants to be planed in the opposite direction.
Author:  BruceHerrmann [ Wed Feb 27, 2008 12:45 pm ]
Post subject:  Re: Bracing A Back (Pics)
Thanks JJ and Hesh, I've been using water stones with just ok results (nothing wrong with the stones, it's the operator) but may try the glass slab/fine sandpaper as well, think I'll do a side by side comparison and see which one I like best. I agree it's most likely sharpness of the chisel but I do find that the Adirondack I'm using does have a preference for which direction you
remove wood, nothing new there I suppose. I may also invest in some better finger planes, the one I have is a bit bulky for tight areas...
Best
Bruce
Author:  sbrunker [ Wed Feb 27, 2008 11:18 pm ]
Post subject:  Re: Bracing A Back (Pics)
Hi Hesh,

As always, thanks for posting things like this.

I remember you and someone else commenting awhile back that on most kits you need to close the box within a couple of days of gluing in the braces. I think I can attest to this in hind sight as I left my braced back out for several weeks so that I could admire it, I guess. It's pretty flat now; much flatter than the 20' it's supposed to be. The thing that's peaking my curiosity as I read this thread is this: What is it that you're doing differently here that keeps you from having to worry about your braces going straight on you?

If you made me guess, I'd say it's a combination of using a 15' radius and having a good go-bar deck and evenly sanding the lining in the radius dish, but I'd sure like to know for certain. There are a couple of things that I didn't like about the way my kit build turned out and the back radius was one of them.

Stuart Brunker
Author:  Hesh [ Thu Feb 28, 2008 12:35 am ]
Post subject:  Re: Bracing A Back (Pics)
Thanks Stuart!

The need to attach a back or a top to the rim quickly is something that has been misunderstood here on the OLF prior.

My position is that if you maintain a stable RH of 42-48% constantly in your shop and a stable, civilized temp too this is not an issue and it never has been for me.

But for many newer builders stable RH is not available to them, yet....., and in that case it would be advisable to have your rim fully prepared to receive the back and/or top nearly at once after bracing.

Many builders, small factories and large alike will leave braced tops hanging around for months or more but the difference is that they have very stable RH at all times.

On another note and sorry to be a pest on this but stabilizing the RH in your shop is really a must if you are going to be building guitars. Several hundred dollars will get you both a dehumidifier and a decent humidifier and a reliable digital hygrometer too. We debate which band saw to buy, which drum sander, etc. but first things first, stabilize the RH in your shop and your guitars will thank you for years to come for it.
Author:  Tim L [ Thu Feb 28, 2008 10:05 am ]
Post subject:  Re: Bracing A Back (Pics)
Hesh,
I have really enjoyed this tutorial. I saw it right after you posted the first pix of the BJR and my first thought was, "that's my guitar". I was in the same place with the Cuban back I started. Right now I am waiting for my squeeze bottles as I am prepping to switch to HHG. Thanks for that, this tutorial motivated me to make the switch now.

I build slow and it can take 2 weeks between bracing and voicing a top, much less the back. Even though the room where I build is humidity controlled, I always leave the partially finished top/back under light pressure in the go-bar deck. So far that has worked for me and I don't feel pressured to finish everything at once.

Tim
Author:  Tim L [ Thu Feb 28, 2008 10:12 am ]
Post subject:  Re: Bracing A Back (Pics)
Hesh,
I have really enjoyed this tutorial. I saw it right after you posted the first pix of the BJR and my first thought was, "that's my guitar". I was in the same place with the Cuban back I started. Right now I am waiting for my squeeze bottles as I am prepping to switch to HHG. Thanks for that, this tutorial motivated me to make the switch now.

I build slow and it can take 2 weeks between bracing and voicing a top, much less the back. Even though the room where I build is humidity controlled, I always leave the partially finished top/back under light pressure in the go-bar deck. So far that has worked for me and I don't feel pressured to finish everything at once.

Tim
Author:  Hesh [ Thu Feb 28, 2008 10:44 am ]
Post subject:  Re: Bracing A Back (Pics)
Hi Tim and thanks for the kind comments!

This is my first go with Cuban Mahogany and I am pretty excited about it. Being a big Mahogany fan successfully convinced and converted by Colin and Dave White I have high hopes for this denser and prettier Cuban Mahogany.

It sounds like you are doing all the right things and I found your comment about bracing a top interesting..... When I build the rim it can be done in several days, a back initially will take very little time for me too. But like you when I get to the top it will take me at least a couple of weeks and at times more to voice the top...... I find it very difficult to call the thing done. Interesting.

And also like you any unbraced plates I will weight down even though my RH is stable.

Good luck with your build and be sure to post pictures along the way and when finished?

Attachment:
DSC01317.jpg


The German/Euro top joined and waiting for a rosette.

Attachment:
DSC01318.jpg
Author:  D Stewart [ Fri Feb 29, 2008 12:27 pm ]
Post subject:  Re: Bracing A Back (Pics)
Very interesting sound hole design. Two questions, isn't 3lbs going to make your guitar too heavy, and how in the heck to you inlay that thing? bliss

Love the toots! I really appreciate the sharing.

Donovan
Author:  RREvans [ Fri Feb 29, 2008 2:27 pm ]
Post subject:  Re: Bracing A Back (Pics)
Hesh - Nice work. One thought/question - any concern over the gluing surface for the braces being sanded? I've always been worried that the "quality" of a sanded joint is not as good as a planed one. Therefore, I always run my little palm plane over the radiused joint to get a clean surface.

/Rob
Author:  Hesh [ Fri Feb 29, 2008 2:44 pm ]
Post subject:  Re: Bracing A Back (Pics)
Hi Rob and welcome to the OLF [clap] [clap] [clap] [clap]

I am not concerned about it - and I agree that a freshly planed joint does make for a better bond but I am not building an aircraft here either...... :D I read a test where a planed joint if glued within 15 minutes is the strongest of all so I agree with your thinking but also think that its over kill for bracing a guitar back.

Again - welcome to the OLF.
Author:  SkyHigh [ Mon Mar 03, 2008 12:33 am ]
Post subject:  Re: Bracing A Back (Pics)
Hi Hesh,

Please excuse me if this has been mentiond by you or others but why do you need to use a stick to put even pressure of BJR? Does it not do the same if you use the dish and use the go bar to push down on the BJR?

Also, I'm guessing BJR is another name for back strip. Can you tell me what BJR stands for?

Thanks, David
Author:  Hesh [ Mon Mar 03, 2008 7:33 am ]
Post subject:  Re: Bracing A Back (Pics)
SkyHigh wrote:
Hi Hesh,

Please excuse me if this has been mentiond by you or others but why do you need to use a stick to put even pressure of BJR? Does it not do the same if you use the dish and use the go bar to push down on the BJR?

Also, I'm guessing BJR is another name for back strip. Can you tell me what BJR stands for?

Thanks, David


Hi David:

You most certainly may install a BJR in a dish and with Go-bars, clamping cauls no wider than 1/2" to aid in glue clean-up and prevent the go-bars from denting the soft WRC or spruce BJR would be advisable too. I have done it this way too.

What I am showing here is a method to install a BJR without the need to own or use a go-bar deck or more than two clamps.

In addition, many builders like to butt the BJR up against a straight edge when gluing it in place. This is harder to do in a dish.

What you see here is simply one of many ways to accomplish the same thing - not better or worse - just different.

I call it the BJR (back joint reinforcement) so as to not confuse it with a "back strip" which LMI and others use to describe the decorative inlaid or butted piece of wood/material that is often running down the centerline of the back of the outside of the guitar.
Author:  DGr33n [ Mon Apr 13, 2009 3:27 am ]
Post subject:  Re: Bracing A Back (Pics)
Thank you very much for sharing, I look forward to learning here at OLF
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