#1 in progress: cedar/mahogany medium jumbo scratch build

Take us through building your guitar step by step. Post pictures and tell us what you're doing.
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nkwak
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#1 in progress: cedar/mahogany medium jumbo scratch build

Post by nkwak »

I've posed many questions on individual steps in my #1 build but seeing this section made me think that maybe I should establish a thread that puts everything in context.

First Installment - the kickoff (August 2010)

Way back in August 2010 my friend had just completed his first build and was embarking on his second. I'd been following his build thread on the Acoustic Guitar Forum and his enthusiasm was infectious. When I played his completed first build (a very lightly-built mahogany/lutz dreadnought) I commented on how rewarding it must feel and how much fun it would be to try. That's when he said to me "why don't you give it a try?"

Even though he was a newb himself he'd bought out an entire workshop of tools and materials from a guy who'd grown frustrated and just wanted all the stuff gone. Part of that deal was several sets of tonewoods that my friend claimed he'd never use and so he offered me pick of the litter and full use of his workshop.

I admit I mulled it over for about a week and even got my wife to grudgingly approve before I took him up on the deal. The only stipulation he had was that I start with mahogany instead of rosewood. The rest was up to me.

At that time I'd just purchased a Martin D-16GT so I didn't want to follow in his footsteps and build a hog/spruce dread. I admit that my GAS affected my decision. I'd just spent some time with a friend's deep OM that was made with Cuban mahogany and western red cedar top and I loved the warmth of its tone. OTOH I didn't want to do an OM because I was also GASing for a Taylor GS.

I couldn't find plans for that Taylor so I stumbled across plans for a medium jumbo with similar dimensions on stewmac.com. The exact model in fact is the medium jumbo as drawn up by luthier Michael Payne and whose sale went toward supporting the Official Luthier's Forum.

Fast forward a few days and the plans came in the mail and my friend and I went into his wood storage room and picked out a set of Western Red Cedar and African Mahogany. Neither of us knew for certain what made for a good set but both seemed to ring pretty nicely when tapped. Here I was wondering what I'd gotten myself into.

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Next installment: getting underway
~ Neil
nkwak
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Joined: Sat Nov 13, 2010 9:55 pm
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

Second Installment: Getting Underway

Late that August I stole away to my friend's workshop and with his help (and a little fear power tools) we used his jointer table to set about joining the top and back plates. We used the Kinkead method of using a work board, a steel rule and a few nails as well as anything with significant weight to act as a clamp:

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Enter the first setback. After I'd left and the glue had had enough time to set my friend removed the plates and discovered that my WRC top had failed along a grain line. SO he had to rejoin along that break which thankfully was very clean:

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That's pretty much where things stayed for a couple of months. My friend's work schedule became hectic and my kids kept getting ill so we couldn't get together in the shop very much the remainder of that year. He and I also had a helluva time trying to keep the belt on his thickness sander. Eventually we got the hang of it and my boards were down to about 1/8" and ringing like gongs when tapped.

Up next: jigging it up during the downtime
~ Neil
tippie53
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by tippie53 »

nice use of gravity clamps
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
nkwak
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

LOL, yeah that's my friend John's little claim to fame. He has this thing for Wile E Coyote!

Anyway, where was I? Oh yeah..

Third Installment - using downtime to build forms, templates, jigs, etc.

My friend and several others online told me that it would be best to make the mold and bending forms out of MDF. The problem for me is that the stuff is really hard to work with. Nasty stuff too, IMO. I glued three sheets of the stuff together and attempted to trace the outline from the plans on to the MDF using a template that I made out of really thin plastic. That in itself was hard enough but cutting through a piece of MDF that thick exceeded my meager skills with a band saw:

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So I decided to start over using a different method and set out to build a semi-solid outside mold out of birch plywood with soft wood spacers instead:

Using the template, I got one profile as close to perfect as I could...

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...then I replicated it as best I could 3 more times:

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... and then add in the spacers and use the cut-outs for spreaders:

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I'm leaving a lot out here but at this point nearly 6 months had passed and I was getting antsy. I got lost in the finer details and really poured myself into getting not only the mold near as perfect as I could - and nearly drove myself nuts in the process - but also made a number of plexiglass templates and even recycled my MDF cutouts to make the bending form for my friend's Blues Creek Fox-style bending machine:

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Like I said, I was antsy. Downright bored if I must say. The word "obsession" was uttered by both my friend and my wife but I kept telling myself I was learning something by doing all of this. Maybe it was the frustration of not getting to work with the thickness sander with any regularity but I needed to keep busy.

So I tried building some more things, like luthier clamps:

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I even started buying up tools from Harbor Freight and Rockler. I even came across some actual Honduran mahogany at a local lumber yard. I bought a nice 6" x 3/4" x 24" riftsawn piece that I'm planning on using to make a 5-ply laminated neck. As I type this, it's been sitting for about a year waiting. It should be acclimated by now IIRC...

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Anyway, like I said by this time my family was growing concerned. My friend stepped in and told me that maybe it was time to start working on something else...

Next time, time to do the rosette:
~ Neil
Jim_H
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by Jim_H »

I love threads like this. It's always cool to see how others do things.

BTW, once you get a good template, you can cut your forms close with the band saw, and then get them 'perfect' using a bearing guided router bit.

And I feel your pain about the MDF thing. I've been building a bunch of forms, mostly from MDF, for the last week, getting ready for my next project. Needless to say I'm getting better and dust control (I hate that stuff!).

Keep the updates coming! =)
My poorly maintained "Blog"
nkwak
Posts: 650
Joined: Sat Nov 13, 2010 9:55 pm
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

By this time it was October 2010 and I'd gotten the mold ready and the cedar top to the desire thickness of about .125".

Installment 4: inlaying the rosette

Actually, I should call this one misadventures with a Dremel and the perils of tearout. I made many coasters in an attempt to execute my rosette design:

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Like I said: obsessed. From past experience I know that the devil is in the details. Chalk it up to being a graphic artist and digital typesetter in a former life. At least I got to use some of my old Adobe software to doodle.

Executing the idea using real-world materials is more challenging than just sending a digital file to a printer and having them deal with that headache to make plates and mix the inks. This time I had to learn how the other half lived and get around my lack of mechanical skills. Like the bandsaw and the planer, the Dremel with circle cutter also scared the hell out of me. In the end I rushed things and made a lot of waste:

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My friend even lamented that I beat up his prized work table, but that's a crock. He'd already cut a lot of circles and drilled a few holes into it doing the same thing!

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In the end, my design had to change because my little rosewood ring just couldn't hold up to my ham-handed ministrations. I ended up cutting a much thicker piece to make it work. Then I came up against the tendency for my cedar top to tear out and I have to admit that my skills with inlaying the purfling strips also suffered. By this time I was already committed and getting lost in the build.

TO make a long story a bit shorter, due to schedules no jiving and the holidays it took 3 months to get to this point:

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Some would say I was getting lost in my work!

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That's not all that was going on though. My friend had give me some homework to pass the time during the break. Next time, splitting the billet:

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~ Neil
nkwak
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

Jim_H wrote:I love threads like this. It's always cool to see how others do things.

BTW, once you get a good template, you can cut your forms close with the band saw, and then get them 'perfect' using a bearing guided router bit.

And I feel your pain about the MDF thing. I've been building a bunch of forms, mostly from MDF, for the last week, getting ready for my next project. Needless to say I'm getting better and dust control (I hate that stuff!).

Keep the updates coming! =)

Yeah, MDF is nasty stuff. I do NOT recommend working with it indoors if you have no method of dust control. I was worried I was poisoning my family by working with it in my basement during the winter months last year!

I don't own a router though, nor any means of shaping with anything approaching accuracy. I just eye-balled a lot of my cuts with a hand drill and sanding bobbin.
~ Neil
nkwak
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Joined: Sat Nov 13, 2010 9:55 pm
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

Moving right along...

Installment 5: beginning the bracing

Looking back only about 4 months had passed but I felt like I was falling behind schedule but as you'll see it turns out that I was doing pretty good. Mistakes were yet to come...

In the meantime, I had a bracing billet to work with. I bought some more hand tools and got to work:

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I felt like I was getting closer...

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By this time the holidays were over and I was able to get back to my friend's shop and work on the sides. THAT'S where things started to get crackin'!

(that's a little literary license with wording - some would call it a "pun" - that has ominous implications!)
~ Neil
nkwak
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

Installment 6: bending the sides

If you look at one of those previous installment's pics you'd notice that my MDF bending form was close to being complete. In fact, after a few more sessions with a T-square and a carpenter's scraper I was indeed ready. At my friend's shop my sides were now thickness-sanded to the target thickness and cut out to the profile where the back rim had a taper. I was chomping at the bit to experience one of the most exciting parts of the building process. So last February we got to it:

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Enter the human element however. The moral of the story is don't rush things. I actually made TWO glaring errors. The first was immediate and painful, the second more subtle but with greater repercussions.

Careful there...

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Awwwwww,@#$%^!@!

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Like I said before, I really got crackin' (feel free to moan at the bad pun here) but that wasn't the worst of it. By this point I had yet to bend the other side and I'd just gotten myself nice and frazzled. So much so that I forgot to simply slide my bending form to the other side of the bending machine and... well, you know what happened: I bent two left sides.

I didn't figure that out until a little later though - after I'd glued in the blocks in fact:

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After I'd pulled the sides out a couple of times I noticed that my sides looked "twisted" somehow. I was heartbroken. Since the blocks had been glued in it would be major surgery to remove them and steam the good side flat and bend it all over again. The other option would have been to sand or plane it all down but that would involve reducing the resulting depth of the body and I didn't want to do that.

At this point I imagine that I'd frayed a few more nerves other than my own but I wanted to do it all over with a new set of sides. I even began looking around to see if I could find a set of mahogany sides that would match my back. I contacted tippie (who my friend had bought the sides from indirectly) but in the end my friend just grumbled and handed me another set from his stock. He had me cut the neck block out of the sides and they went into the scrap pile to become a guitar-shaped cat litter box.

In the end I think we both came out ahead. He'd become involved in a local woodworking club and he wanted to demonstrate bending wood for them. All I had to do was thickness sand them and cut them to the rough shape with my template. Well, I got to work and he took his bending machine and my bending form and it was a big hit. For my part I got to do it myself again a third and final time.

Several months had passed during this time and other things got accomplished but by late May 2010 I was back where I'd started from:

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I even went a little further on my own and opted to forego the solid mahogany tail block for one I made myself out of laminated birch plywood. I own a Larrivee OM-03R and I was amazed to find that this was an intentional feature that Jean Larrivee used for durability. I decided to emulate it because I'd had enough experience with key cracks.

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Next time I'll switch focus to my top and back plates which were getting some attention at the same time.
~ Neil
nkwak
Posts: 650
Joined: Sat Nov 13, 2010 9:55 pm
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Re: #1 in progress: cedar/mahogany medium jumbo scratch buil

Post by nkwak »

Installment 7: beginning on the plates

Last time I confessed my sins with mistakes made on the sides. This time I'll share some more with regards to the soundboard bracing. First things first though, I did some work on my back plate including a decorative strip:

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I haven't mentioned it beforehand but I purchased rosewood to use as body binding. My rosette ties into this theme but I'd never really warmed up to the idea of having such a strong line run down the center of my back. So I opted to go a little subtler and procured a flamed mahogany strip instead. As with the rosette, my inlay skills aren't quite up to snuff so that the BWB purfling could look cleaner but I'll deal with that during the final sanding. Meanwhile, I also installed the reinforcing strip:

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Moving right along though, I was really looking forward to bracing my soundboard. I had it all prepped and ready:

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My braces were pre-cut and ready to go and after an hour of scraping my knuckles on a sanding disc in a 28' radius dish I moved on to the initial glue-up. My friend had decided to let me make my own mistakes from here on out, but he still liked to get involved:

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At the same time I was working on the blocks for my sides and glued up the upper transverse brace at the same time as my neck block extension. See if you can spot the mistake there!

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~ Neil
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