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Ugh;

Total newbie mistake. I made my bridge plate a bit too small and glued it in too far forward (HOW DID I DO THAT???). My bridge pins mis the back edge of it.

So...

I guess I'll be learning how to remove and replace a bridge plate from inside the box...

fun fun fun fun fun.

Nope , I did same thing once. I made a "add on Plate " and glued it tight to the back of my existing plate and went on , no issues to date . Just end up with a larger than normal bridge plate .




Blue is bridge Plate , and bridge where its supposed to be . was fairly easy fix

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

It may be easier to graft an extension on the back edge of the bridge plate rather than trying to remove the existing one. ( I see WudWerkr already suggested that)

What I would think about doing is using a scraper to thin down the existing one and then adding the extension to the back the same thickness you scraped the original one down to and then laminating another piece over the plate and the extension.

I have done a couple of repairs to cracked bridge plates by the same method. It takes some careful scraping to make sure you get it an even thickness but it is still better than trying to remove the old plate. Removing the bridgeplate in a closed box is really hard to do and you run the risk of tearing out (or even splitting) the soundboard.

If you insist on removing it just for the experience then what I would suggest is buying some 1/4" ceramic blanket and cut it a hole just smaller than your bridge plate.

First remove the bridge, then lay the blanket on the top of your guitar just over the bridge plate. Lay an iron on the blanket so you are just heating up the area over the plate. You will probably have to make a tool out of a flexible putty knife so you can get it under the edge of the bridge plate. Very carefully slip the blade under the bridge plate and try to separate the plate from the soundboard. You will have to work in stages by applying heat, prying the plate and apply heat again. But you will be able to remove it with some care.


The ceramic blanket can be bought at a place that supplies fire brick and fireproof materials for wood stoves and fire places.

Here is the blanket I use for removing bridges and the tool I made for separating them apart. The blanket will protect anything up to 2500 degrees and I can lay an iron over a bridge and when it is hot the surrounding area is not even warm.

On the tool, you will want to thin the end of the blade down but DO NOT MAKE IT SHARP. round off the corners and put a bend in it so you can get under the plate. I say do not make it sharp from experience... It will cut right into spruce really easily and before you know it you will be prying up chucks of your top.

I have removed a couple of bridgeplates on instruments that really needed it but I would advice the faint of heart to never attempt it.

Sorry guys I have to be the contrarian here.

Bridge plates need to be one continuous piece and here's why. The plate is part of what I like to view as a system that includes the plate, the top, and the bridge. When a bridge plate cracks, often along the pin holes, it compromises the system and can contribute to a bridge lifting because the bridge is no longer mounted on a continuous top and bridge plate. Instead the cracked plate, or in this case a two piece plate will not remain flat or the radius that you intended when it has a weak area where it's cracked or pieced together, again in this case.

When bridge plates are chewed up along the pin holes we install a very small bridge plate "cap" which is typically perhaps .060" thick, about 1/2" longer than the pin spacing and around 1/2" wide. The cap is overlaid on the damaged plate reinforcing it and preventing the damage in the pin hole area from becoming a crease or worse, a crack. Pin holes are drilled though the cap with a backing caul or drilled prior to installation. The pin holes are reamed and the pins properly fitted and Bob's your uncle.

So if it were my ax and if the pins need to be just beyond the plate as currently located I would remove the bridge plate and replace it in the proper location.

Piecing together multiple plates adds unnecessary mass to a very important region of the top and it also has the prospect of defining where the plate will deform in time and possibly crack or separate. Make efforts to joint the two pieces together with something to overlay them both and you just added more mass again in a very important region of the top.

Removing the plate is not difficult and is done all of the time in the repair world. You do need to know what you are doing or you can split the center seam of the top.... A few shop-made special tools are helpful too.

Thanks for the input guys.

I'm going to try to replace it. I'm in this to learn. Every mistake I've made has been an opportunity to learn something new.

I've ordered a bridge plate removal iron and a "u" shaped pry tool made for removing bridges.
It sounds like if I lay a damp (but not soaking) sponge on the bridge plate for an hour or two, (face down), then apply heat with the iron for a few minutes I might be able to start to work it loose.
I'll go slow and be patient.

I don't remember if I used HHG or fish glue (I think it was HHG) but heat and moisture should get it loose.

Good going - that's the spirit!

Either glue will release with heat and a little moisture and with fish if you just wait a couple of years the thing may just fall off.... Kidding of course...

I will pose this question to Hesh.

Is it not true that 2 pieces of wood laminated together are stronger then one piece alone? So by shaving down the thickness of the bridge plate and laminating another piece over it (much like you do when fixing worn bridge pin holes) make that piece stronger then the original? By grafting an extension on the back of the (too short) bridge plate and laminating another piece over it make it much stronger, providing the extension is a tight fit?

I am sure that some will say it will effect the sound (and I am one of those) but to what degree? The repair of worn pin holes does exactly that so advocating a laminated repair for pin holes is no different than what I am talking about.

I would probably replace the bridgplate myself but for someone that has never removed one it would be much less of a frustration to repair it. I did my first couple on junk guitars and I did end up ripping a big chunk of soundboard out of the first one I did. I have probably done 3 or 4 on client guitars in my time and I still sweat like a pig while doing them (not because I am working hard but out of nervousness that I will screw up a soundboard. It is amazing how tough peeling Maple off of spruce can be...

Cheers,
Bob

Hesh's advice is sound. This is not the first time it happened to someone here. I can't stress this enough be sure of the scale length and brace positions before you put the top on.
If braces are not where they belong your guitar may have issues waiting to come forward later.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I have to agree with this statement , What I suggested is a "fix" not Necess. the Best Option . In my case , I didn't wish to attempt to take it off and replace it . First Guitar , its not going anywhere anyway .

Good on you for attempting the repair . Let us know how it works out

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

taking a plate out is job we have to get to be good at. There are many ways to do this. Martin uses a wet sponge over night and this helps water penetrate the wood to the glue surface. If you need heat the water lets the heat penetrate more efficiently .
One learns from mistakes , so this is more a learning experience than a mistake.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

For any new folks just starting out remember to draw the location of the bridge plate to a known reference when laying out your bracing pattern on your top. The reference to use is where the neck meets the body. IE the 12th or 14th fret. From there you know exactly where your saddle will be located. From this draw a light outline of your bridge shape and then it's easy to see exactly where your bridge plate should be located. Now the only thing to remember is to use the same reference point when gluing the top to the rims.
Tom

_________________
A person who has never made a mistake has never made anything!!!

To expand on Tom W's comment, it's a good thing to measure from the 14th fret when building 14-fret guitars, and from the 12th when building 12-fret guitars. Don't ask how I know...

Bob buddy there are actually a couple of issues here that play into your question about how strong multiple pieces of wood may be.

First and very much related is the seemingly unrelated issue of what's appropriate for the instrument. We won't reset a neck on a $199 Asian import assembled with AMG (Asian mystery glue) and likely with a doweled neck joint never intended to be serviced or reset. The cost of the repair is beyond the value of the instrument and unless there is sentimental value and an abundance of coin on the steward's part it's a disposable guitar.

Likewise some of the other repairs that we might do to keep an instrument singing will also play into that cost, benefit equation. What we might do and pay for for say a vintage Gibson or Martin with substantial value might and at times will cost more than the original cost of the instrument and even perhaps more than a new one these days.

It's all about what's appropriate for the instrument and always a consideration in the repair world.

This is an early guitar, a learning experience, it's also largely hand built by the OP and represents an accomplishment of sorts. It may be something that gets gifted or passed down over the decades now as a family heirloom.

Just like all of us I assume that the OP wants to do their very best and likely will and with some patience, lots of learning, a bit of humbling at times, I suspect that they will produce something to be proud of. Very proud of.

So maybe it's me but to my way of thinking what's appropriate for "this instrument?" Everything, taking the time and effort to do it right if not the first time but the second time. Removing and replacing the bridge plate preserves the original intended design, should never be noticed that it even happened once remedied, and eliminates any possibility of introducing any areas that will prematurely fail or cause or contribute to a chain reaction failure such as a crease under the bridge causing it to lift prematurely in time.

It's doing it right!

Regarding strength and bridge plates the strength required for a plate could be described as strong enough.... Meaning that the intended design, as designed is likely fine but this is not what we have at present. Sure you can piece something together but to me an acoustic guitar is a very high-performance thing built two steps back from the brink of implosion engineered and designed to be a very efficient, acoustic transducer of sorts with like most things a functional dependency on it's design. It's a time tested design and no matter what we might come up with these days it very may well have been done before and is simply new to us.

If we will "cap" when "appropriate for the instrument" a bridge plate we are not only renewing the plate surface where the strings balls like to feed... but the cap also acts as a splint of sorts belaying and reducing the possibility of the all too common bridge plate crack along the pin holes. Are we adding extra mass - sure, is the repair ideal, no, is it at times appropriate for the instrument - yes!

Likewise my point is that this guitar needs to be built to a standard that was intended and since it has never sung it's first note yet why not simply remove the plate that is in the wrong place and install a plate where intended?

Additionally this error could be a nasty one because bridge plates DO crack along the pin holes commonly. In this case right where two pieces might be joined, even if reinforced, is very close to the pin holes or where the pin holes need to be for the intended scale length. Anything can be splinted, doubled, capped, edge joined etc - but this of all places is not the place to risk it.

In my world everything gets weighed and stacked up against my own building notes and design goals. I want the bridge, top, plate system to have as little mass as possible to both overcome and/or stimulate. I'll take it a bit further - IMHO adding mass when you don't have to in this critical area is perhaps the most mass-sensitive area of the entire instrument and to be avoided. When the fix is simply doing it correctly why not?

As for tone, too subjective for me to comment. Does mass impact tone for better or worse - you bet. So in that sense your tone and my mass are likely talking about the same consideration.

By the way this is a mistake that I have made years ago too and I know others who have located the bridge plate in the wrong place too. We removed and replaced and all was well. I'd like to be sure that what we advise our friends here to do when they ask us has the highest probability of getting them where they want to go.

Currently the instrument is not finished and even easier to work on to get the plate off and replaced too.

And most recently after reading what they intend to do I have a feeling that they will pull it off very well in more ways than one too!

PS: Remember that we have some fanatics on this forum who may weigh every single piece of a guitar top with a gram scale....

Here's a hand made guitar that a guy brought in for a pickup. At least you identified the problem before it left your shop. I agree with your decision to replace the bridge plate. Let us know how it goes and take some pictures.

_________________
It's not what you don't know that hurts you, it's what you do know that's wrong.

OK, I stand corrected.

I guess because I am just a "repair guy" and not an authorized Martin or Gibson repair center I don't have the luxury of just dismissing a repair over a complete replacement. I was giving my honest opinion on how it could be repaired without removing the bridge plate. I don't have the luxury of turning a client away because they have an inexpensive guitar. I try to do my best to help people in a way they can afford. In some of those cases a repair can be done for half the cost of a replacement. But then again that is probably why I am not getting rich repairing guitars... I also buy guitars to fix them just so I can give them away... so call me stupid...

I know the OP said he was going to try and remove it and I commend him for that. I know he will learn a lot by doing it and that can't be a bad thing. But I was giving him my option on a way to repair it.

Cheers,
Bob

Always lots of approaches in all things Lutherie Bob my friend.

My impressions were also weighted by the idea that this is a new instrument and that ole "appropriate for the instrument" consideration.

There is another thread right now where the repair guy reset a doweled neck joint. In that thread I give three possible options (actually there are four but ceremonial burnings of musical instruments may be frowned upon by some.... ). Anyway this stuff is never cut and dried so-to-speak and we have to consider budget, value, sentimental value, if the instrument was a piece of crap to begin with with Ov*tion.... coming to mind, etc.

Terry I can hear in my head Don Adams of "Get Smart" saying "missed it by that much...."

Here is one that the Top and bridge plate were both split and had to be repaired . Is this best approach , doubt it But its what I did on a 250.00 guitar and charged 125.00 sounds good and customer was/is extremely happy



The Hole I cut is apprx 1/8" smaller than the bridge itself . I then laminated anther filler to level it with top gluing it in cross grain to the new plate and then reapplied the bridge . Rather Simple really

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Hi ya Wud!

Well it's not the approach that I would have taken but if it works it works, right? On these inexpensive insturments sometimes we break the rules and hope that the Lutherie police, or, whomever has appointed themselves to that role this week.... don't see it.

What I would have done which is really no more work than what you did is not route through the top and instead piece the top back together even if I have to add some spruce. Make a very clean, level bridge patch, chisel the finish away to just inside the perimeter of the bridge foot print and then reglue the bridge.

Frank Ford has yet another excellent toot on his site about piecing together damaged tops.

The bridge would of course be cleaned up as well and we rabbit our bridges making a pocket in the finish for an exact fit AND it holds the bridge in place preventing the slippery HHG from getting the bridge out of place. Then it's all reglued and Bob's your uncle...

On the underside same thing, remove and replace the bridge plate etc.

But again sometimes being creative with repairs so long as the thing does not have much value in any respect including sentimental value can help get your clients where they want to go.

My hats off to ya for learning some repair work. I initially thought that I would use learning repair to be a better builder learning how and why guitars fail. Along the way I fell in love with repairing instruments and now view repair as where my focus will primarilly be although I still build. Besides too I get to meet some pretty famous people, help them out, get free passes to their shows, etc.

It also gives you a view into some practices that we may have done building that from a servicability perspective may..... suck.

So repair is a great thing to learn. Kudos to Rick Turner for shaming us all back in the day into considering learning repair - he was right!

That's Kind of my Idea here as well . I enjoy building but as I get closer to retirement I want to sell my business and semi retire with Repair work as my back up . Best laid plans huh

_________________
The Shallower the depth of the stream , The Louder the Babble !
The Taking Of Offense Is the Life Course Of The Stupid One !
Wanna Leave a Better Planet for our Kids? How about Working on BETTER KIDS for our Planet !
Forgiveness is the ability to accept an apology that you will probably NEVER GET
The truth will set you free , But FIRST, it will probably Piss you Off !
Creativity is allowing yourself to make Mistakes, Art is knowing which ones to Keep !
The Saddest thing anyone can do , is push a Loyal Person to the point that they Dont Care Anymore
Never met a STRONG person who had an EASY past !
http://wiksnwudwerks.blogspot.com/
http://www.facebook.com/groups/GatewayA ... rAssembly/

Update: I applied a sponge wet with boiling hot water to the bridge plate inside and let it sit for a couple hours. Then I applied 2 minutes with a searing hot "Brown's guitar factory" plate iron, then I worked at getting the pry bar under the edge of the plate. I had to do 5 rounds of this over an afternoon. It eventually worked and the bridge plate came out in one piece.



I had some tear out and next time will be even more patient.
I think the bulk of the tear out happened when I first got the pry bar edge under the plate. More wet and heat before getting aggressive with the pry bar next time.



Now I have the old bridge plate to use as a template for its replacement.

Upward and onward!

Good job!

Some food for thought. When HHG or Titebond original are used on a plate or a bridge, etc. what we want is to get the glue to soften and then carefully with pallet knives (curved as you did your pry bar) we slip them into the softened glue joint and work our way through this bond. We don't pry and we take note of the runout direction on the specific top and file this in our minds so that we can approach the plate, if at all possible, in a direction that encourages the runout fibers to lay down instead of digging into the top.

Too much heat or moisture or excessive duration with either can also separate the top seam and ruin your day.... If you hear the fibers you are lifting them instead of pushing them back down.

My hats off to you Linus for your efforts!

The new bridge plate was successfully glued in its proper place and tonight the bridge was glued on. I can see the end of this process. Very exciting.



Thanks for the support and advice everyone.

Congratulations! Aren't mistakes great? One less thing to fear.

_________________
It's not what you don't know that hurts you, it's what you do know that's wrong.