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I just bought a book "Step by Step Guitar Making" by Alex Willis and have a few questions about the OM design. It could be that this book just does it this way, but I want to make sure.

1.) The book builds the guitar similar to a Classical guitar where the guitar is constructed around the neck. Can I build this similar to how I am building my Dread., where I construct a box and use a mortise and tenon to attach the neck?

2.) Also pertaining to the neck, he gives the heel block a lot of surface area where it mounts to the back of the guitar (kind of reminds me of John Mayes method of attaching the fingerboard except instead of being towards the Front of the guitar it's towards the back). Is this something specific to OM guitars? Does it serve a purpose? Or could I make the Heel Block (I believe that's what it's called) just a block? (sorry if this question isn't clear. I'm having a hard time trying to describe it).

3.) Am I correct in thinking that the OM guitar is normally a 25.4 scale length? The plans for this guitar are for 25.5 Scale length. I assume I could just use the 25.4 Scale and be perfectly fine right?

4.) What plans do any of you that build OM guitars use? Perhaps I should go that route as well.

I've only skimmed through this book so far, and I know it sounds like I'm trying to be difficult by not wanting to build it per the book, but basically I bought it online and wanted to build the same way as I am on my first Dread., only a different size guitar. Maybe once I get comfortable building this way, I would attempt to try a different method (like this book lays out), but for now I just wanted to get comfortable building one way but hoped to build different models as well.

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Blain, I'm building my first OM now and using the Kinkead book. I'm using the same neck I use on my dreads. Mortise/tenon bolt on with 25.4 scale. It will work fine.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Thanks Ron and Hesh.

Ron, glad to hear that you're building it this way. I purchased over the internet and assumed that this was how the plans would be and was surprised to see it was so different. Maybe one day I'll come back and try to build it per this book, but for now I think I'm going to go with the way you're doing it and the way that I think I'm most comfortable with. Good luck with your first OM Ron. I can't wait to see the finished product to give me something to look forward to.

I decided to go ahead and purchase the Plans by Michael Payne per your recomendation Hesh. Glad you decided to stick around.

Hesh, if you don't mind me asking, what plans are you using for the L-00?

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Hi Blain,

I bought the antes plans and am doing exactly what hesh mentioned....brace lighter..
Robbie O'briens DVD I find very useful....
but for the spanish heel method you are doing you could have a look at Jim Williams book as it is building using this method.

Be aware Blain that My plans do not detail the neck specifically. I did this because most luithers have their neck designs already. My OLF OM is based off a Martin OM and can be adapted to any neck and neck block configuration including Commercially available pre-carved necks From Jon Watkins, StewMac or LMI.

Thanks Hesh. I'll look for the Mark Swanson L-00 plans on the MIMF.

Thanks for the heads up Michael. I'll just use the neck detail that I already have and it sounds like that should work fine. I look forward to seeing your plans.

Another question for you all.
Has anyone made the depth of the body (sides) deeper on the OM?
If so what depth did you use and how were the results?

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

When you change the depth the chamber resonance changes. That is not to say it will make a bad guitar. if deeper then the guitar is likely to have a hollow, woodier sound.

The other issue when you do that is finding a case for the guitar. OM case are pretty much based off of Martin OM specs so if you go deeper you may have to have a custom case made.

I think what I'm looking to achieve is more of a "deeper" sound rather than louder. Maybe as Michael said "hollow" or "woodier" would be the word as well.

The issue of the case is a good point as well. I hadn't thought about that.

Well, I know I'll build at least one first to Michael's plans before I go tinkering with the design and trying new things. It could be that I fall in love with it's sound just as it is.

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

I really can't take credit for the design of the OM out side of the optional X-braced back. My OM plans were derived from a Martin Kit I built years ago. So the design is basically a Martin with a lighter bracing scheme.

[QUOTE=Hesh1956]

If as I suspect, you are looking to make it louder I don't think that this will get you where you want to go.

I made the body deeper on an OLF SJ and already had an OLF SJ built to plans to compare it too. The deeper one was no louder than the one made to plan. In fact the deeper one lacks the responsiveness and "punch" of the one made to plan.[/QUOTE]

Ive heard that deeper bodies on OM models actually do increase volume on that particular model - but only to a point, I believe...
There was a discussion with several people in the MIMF forum (proly archives now) that had done OM's this way, what they had done - what worked, and what thier magical depths were for achieving volume increase in the said model.
Cheers
Charliewood

whilst spanish heel steel string guitars are not unheard of they are rather rare. jim williams, australian builder of some note and is another author of a building book as well wherein he illustrates his spanish heel steel string construction technique.

it obviously can be done, but it is much easier to build a separate neck and body, an down the track some poor repair person will be casting aspersions on your intelligence, or lack of it, your ancestry, etc., etc., come neck reset time if you go the spanish heel route.

as to your question about the foot of the spanish heel, it is just a part of than method of construction. it is not anything to do with an om or any other model, just the method of construction.

most om's are nominal 25.4" scale, simply because martin originated the model and they used 25.4", or as hesh points out actually 25.34", but 25.5 would work fine if you were to use it.

the thing to realize is that if you work from different plans/design specs there are small details which you have to reconcile to ensure you end up with a whole that works as it should. if you are going to do this you should do a complete, full size working drawing of the guitar as you intend to build it.

personally i feel that if you really wish to build excellent guitars, and particularly if you want to sell them and have long term satisfied clients, then when starting out you should build from one well established and recognized plan, build enough of them that you can get a rally good, consistent degree of excellence in that one model. when you have achieved that, then go on to doing variations on woods and bracing to learn the effects of your changes, on that model.

only when you have done this model sufficiently to be able to reliably predict what result any given change in wood or specification will make should you then begin the process again with a new model.

I tend to agree with you Hesh. We have a given amount of energy driving two different sets of air mass the lesser mas is driven with more force than the larger one. Now with that said there are resonance issues in the problem as well. But in my experience from the one and only deep body 4 1/2" OM I have built the mid tone was flat sounding the bass lacked punch and the sustain was most certainly diminished on the high end.

Hesh,
I should say that I have no experience whatsoever with building OMs at any depth and to take my statement for what its worth - which is what I charged for it
anyhow there was a lively discussion on the MIMF about this as I said... and I would find the link for you,
although I can never find anything in the MIMF archives!
And I find it to be a really confusing ordeal looking through trying to find something specific there.
Cheers
Charliewood

I just finished up a 4-5/8 or so deep body Cocobolo/40 year old cedar topped OM venetian .. it did not lack for bottom , mids, highs, sparkle, volume or sustain - it had it all in spades, and is one of the best guitars I have built. The top was floppy as all get out, and it ended up at about 140-145 thou in the rough, so maybe 135 finished .... some things just WORK. It had my regular symetrical X brace and sizings.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Oh .. forgot .. it was a 13 fret 24.9 scale, wide 1-7/8 nut with a slotted headstock, 3 on a plate Waverlies, lower bout was 15 5/16. So maybe not technically an OM ... but I still call it one, curves came off a Martin ... thats really all I wanted, as that particular one sucked huge - it was awful, but stll useful for something - plagerism !!!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

.140-.135 and the top was floppy. Wow my Om tops typically are .125-.115 range and pretty stiff. No doubt intended. Just an observation.

Yeah, floppy at that thickness, just the particular chunk it came from, got 4 tops, but they sure make nice guitars. Most of my regular tops in sitka/lutz/adi are closer to 110 on average, maybe less for a really stiff piece. Even some cedar I have is about 115 at the flex I like

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Blain;
I've used both neck to body construction .
If you use the spanish foot type -where the side slots are cut into a heel block you still have to have a neck angle so the arched top and neck will join up .-PLUS for the correct string action for the life of the guitar!
Just as you would have for a dovetail or mortis & tenion!

take your time and find what is best for your guitars !
www.collinsguitars.com

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Mike Collins

Just for you Hesh ....

Karol OM venetian, 40 year old cedar top, coco B&S, headplates, Braz bound soundhole and bridge, Laskin armrest.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Wow! That's a beaut Tony!

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Dave Rector
Rector Guitars