Making a New Guitar Back Plate
Source: Guitar Plate Repairs
Making a New Back Plate:
The time will inevitably come when despite all of your best efforts, a back plate cannot be saved. You are then faced with the prospect of completely re-constructing the back and replacing it on the instrument.
I’m not going to repeat all of the lengthy steps required for making a new back plate for the guitar in this article. We do have some very detailed, informative information on exactly how to build a guitar back plate from scratch on Ultimate Guitar Building. The articles you will want to read are:
Guitar Brace Selection:
Guitar Back Selection:
Guitar Back Preparation:
How to Make a Back Reinforcement Strip:
Installing Guitar Back Purfling:
Bracing the Back Plate:
How to Make a Go Board Tool:
On To Back Plate Replacement:
Once you have absorbed all of the information in these articles we can continue with the business at hand – replacing the back. I would like to supplement some of the information in the above articles to more closely address a back plate replacement vs. a new guitar back plate. Some things you should be aware of are:
Match Wood Figure, Species and Tone:
Be sensitive to the wood species and figuring of the existing back. If you have a chance to keep the existing back, you should try to match your new back plate wood as closely as possible to figure and color tone as you can.
While most species of wood have common charteristics, the wood figure and color tone can still vary quite a bit. The best option is the ability to sort through sets of wood backs at a instrument lumber supply house. If that isn’t possible, some of the online wood shops have pretty good photos of each wood set you can purchase.
Note: that you will most likely have to purchase both back and side sets together as that is how they are produced. The exception to this would be to purchase nominal lumber to cut up yourself.
Match Existing Guitar Appointments:
Also, when joining the back plates, use a purfling, reinforcement strip and bracing of similar size and appearance to the original guitar. If possible, reuse the existing guitar back plate bracing.
Locate Bracing:
You should also be sure to locate the bracing in exactly the same location as the existing back. Cut the scalloping at the brace ends down to the same height as the original.
Dry Fit The Back:
Now, once you have built the back plate, dry fit the back on the guitar sides. This can take a bit of doing and you may need to make some adjustments to the lining channels where the bracing is inserted. Make sure the back is centered and lined up properly. Take a pencil or marker and trace around the underside of the back, about 1/8″ out from the sides.
Make All Your Preparations:
Prepare your Clamps. Make sure your spool clamps are ready for instant use, are properly opened and you have enough of them to span the entire guitar perimeter.
Check to see you have your (2) Wooden Cam Clamps with the required cauls for the head and tail blocks.
Grab a roll of masking tape and cut about a dozen strips, each 4″ long. Have them ready to go too.
Glue:
If you are gluing an exotic wood back plate, you will want to use the slow set one hour epoxy glue. Mix the glue immediately prior to starting the gluing operation. If the plate is made from a non-resin sourced wood, you can use Titebond III.
Spread the glue over the linings and the tops of the block only. Use a thin piece of veneer to get the glue even. Clean up any spill over now, before to apply the plate to the guitar.
Set The Plate In Place:
Now take the Back Plate and drop it into place. Align the Plate over the Tail Block and place a piece of masking tape to the side and pull it over the back and adhere it to the back. Do this at the opposite block, at each waist and each bout.
Now take your Wood Cam Clamps and cauls and carefully clamp the Head Block and Tail Block areas. Check the alignments and adjust as necessary.
Take a Spool Clamp and clamp the waist. Make adjustments to the sides by applying pressure to align the surfaces. Now do the same with the opposite waist. Do this with each bout, both upper and lower. Now it is time to re-check everything. Make sure all edges are lined up and the back plate is seated properly. If you have excessive glue squeeze out, you used too much glue. Clean up as best you can.
Now apply spool clamps shoulder to shoulder all the way around the perimeter, checking that everything is lined up as you go. When done set aside to dry overnight.
Remove all clamps and tape and inspect your work.
Assembly of wood or plastic bindings will be the subject of another article. Finish touch-up will be covered elsewhere as well.
Ultimate Guitar Repair Tip: If you have an exceptional fit between the mating surfaces, do not hesitate to use tape to set the back plate. You can use masking tape with 3 to 4″ long strips. I prefer to have a drafting tape dispenser screwed to the side of my work bench so I can quickly dispense tape from it. If you want a stronger solution, use Filament Tape, where you can apply a lot more downward pressure.
Just start on the back plate surface, hold the plate into correct alignment with one hand and apply a downward pull with the tape and adhere it to the side of the guitar. Do this at about 4″ intervals around the whole guitar and then come back and fill-in. If you have a stubborn place, just apply more tape or use a helper clamp like a spool clamp.
Tags: guitar back replacement, how to repair a guitar back, major guitar repairs, replace a guitar back
