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First of all I appreciate the number of responses and advice I have gotten in my first couple of posts here. Here is a mold I constructed from the Martin OM from LMII. As you can see I have a slight gap near the upper bout (2nd picture). Now if I flip the mold over and butt the template against it again it is near perfect, so during my sanding or cutting I took a little too much off one side. The right side (1st pic) is dead on. My first question, is this "good enough" or should I be doing some patch work or starting over?

In my search of the forum I see some have recommended to spread Bondo around and then sanding until a better fit is made. Any thoughts?

I would be willing to bet you , if you didn't point it out no one would ever notice . go with it as is . that's my call

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I would not be satisfied by that. I would encourage you to find a way to make it symmetrical.

Yeah, I wouldn't be happy with that either. The easiest way would be to glue a few vertical strips of softwood , trim then sand to match the profile. Doesn't have to be pretty lol Oscillating spindle sander works great for this.

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Pat

For an early build that is just fine. If you worry too much about stuff like this you will never actually finish a guitar.

I would build with that, as is

Mark

I doubt that the side would conform to the error in the mold, unless you force that part of the side in.
Sides will normally be held to the mold at neck block, tail block, and the waist with a spreader, may be another spreader across the lower bout.
Y'all'd have to be pretty determined to get the sides to curve back in there.
My 2 cents.
I'd be more worried by the 1st picture where the sides seem to run off the vertical.
Have you put the mold on a flat surface and gone all round it inside with a decent square?
Especially at the head block area?
Top picture, neck block edge, may be camera effect, but looks distinctly curved vertically where the 2 mold halves meet.
Could be fun to fit neck block.
I've thrown out my first 2 molds because they were similar or worse, and still have to fix my 3rd, which is salvageable., 6 builds so far, so won't stop you making guitars, just give you more "experience".

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Bondo

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Hmm... I'll have to check that when I get home today. I might end up remaking a mold since I don't even have the materials for my build yet.

You could easily build up that area with "Bondo" we use it in our shop for many purposes.

That said there is no shame involved in using it "as is" as pointed out something like that would never be noticed and has nothing what so ever to do sound quality or construction integrity.

Guitars built using the "no mold" method are often asymmetrical at several locations around the perimeter.

And lastly -- this is copied right out of the LMII catalog :

" Note: These molds are precisely machined based on the guitar plans referenced above. The plans themselves may be assymetrical, and if so, the molds are also assymetrical. The molds have a top and bottom and a left and right and they are not necessarily interchangeable."

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Ken Cierp

http://www.kennethmichaelguitars.com/

If you are planning on doing more than one guitar I would toss it and start over. If you build one, you might get lazy and do another. It's MDF. Almost free. When it comes time, feel free to ask advice on how to do it easily and accurate.

[quote="Colin North"]

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My thoughts also when I first looked at the pictures.
Tom

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

You would be surprised at the amount of asymmetry that will go completely unnoticed (as long as it fits in the case). Keeping a good center-line is important but small differences in the bouts will be hard to detect in the finished instrument (until you point them out). Did you notice the discrepancy before you put the template up to it? Did you even notice the two sides were different.

As has been said, the side will probably not extent to that portion of the mold anyway. By the time you clamp the heel surface of the side in place and use the waist spreader to lock in the waist, the upper bout curve will tend to fair itself into a pleasing curve. Likely very close to the intended curve. You have to remember not to rough-cut the plates by tracing the template; I always trace the actual rim before I cut out the shape.

All that said, there is nothing wrong with re-doing it if you want it to be perfect.

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Bryan Bear PMoMC

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In my opinion, a little (maybe +/- 0.1") asymmetry in the sides is no problem but I feel it is essential to keep the sides, neck and tail blocks as square as I possibly can.

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Steve Smith
"Music is what feelings sound like"

The upper bout not being tight wouldn't be a concern, but I would want to make sure that where the heel block is would be flat across its width and square to the center line (or at least matching the curve if you are planning for a curved heel block. If it is not flat and square to the center line fitting the neck will be much more difficult. If you put your two pictures together it looks like the block will be tilted to the right just a little.

I agree with every single response that has been given thus far. Sure, you can fix it with veneer strips or bondo, etc. But it's also true that your sides probably won't conform to that little bit of asymmetry. And even if they do, it's not likely that anyone will notice. And even if someone DOES notice, it'll probably be you that notices. So, decide whether to repair the mold, replace it, or press on and I think you'll be okay regardless.

Just go for slightly better next time.

First, I would check it with a square to see just how much out it is. If it is more than a 1/16" I would glue some veneer strips in place, then use a spindle sander if you have one or maybe a file to bring it true.

If you don't true it up then just be aware of it and don't clamp the side hard to it in that area.

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