Looking for advice on the body for my J Bass clone

[sethgali]

Let me begin with this: I don't know anything about basses, I'm a sax player, but I've always wanted to learn. And I've been itching for a while to build one because it looks like fun. The plan is to build this one and then learn how to play it. I'm a moderately capable woodworker with a decent collection of tools and have watched a ton of videos about guitar building in general.

I've always loved the classic look of the Fender Jazz Bass, so that's what I'm working on for my first project. I plan to go with a natural finish and no pickguard. I found full-scale technical drawings of the J Bass somewhere online and have already prepared an MDF template to use for routing the shape of the body.

I purchased a rough cut ash slab in August, and it finally got dry enough to work with last month. It's 56" long, 1 3/4" thick, and averages 14" wide, I'm hoping to be able to cut two bodies out of this in case I have problems. The width is just barely enough for a single-piece body. You'd think there would be plenty of length for two bodies, but now that it has dried, it has a few issues.

It's bowed on both length (about 3/8" gap at the middle) and width (about 1/8" gap at the middle. I should be able to correct this in the flattening process, but it means losing some thickness. It also has a bad check (crack) at one end about 12" long, a bad knot and additional checking at the other end, and some smart imperfections in the middle.

I figure I have two options:

1) Cut out two single-piece bodies as originally planned, cutting around the worst cracks and filling in the knots and other lesser cracks with epoxy as needed.

2) Cut the board lengthwise and get several smaller pieces (probably three each) to glue up into the two bodes, allowing me to not have to work with any of the imperfections.

So that's my first question: which of these options would be recommended by those who have done this before?

I'm documenting progress on my Instagram (https://www.instagram.com/sethgali/) if you'd like to see examples of the issues with the slab. I'm not fishing for followers, I've just already started the process there.

I'm open to any and all advice on this project, so please fire away. Thanks in advance for your help.

Seth

[mistermikev]

1 hour ago, sethgali said:

Let me begin with this: I don't know anything about basses, I'm a sax player, but I've always wanted to learn. And I've been itching for a while to build one because it looks like fun. The plan is to build this one and then learn how to play it. I'm a moderately capable woodworker with a decent collection of tools and have watched a ton of videos about guitar building in general.

I've always loved the classic look of the Fender Jazz Bass, so that's what I'm working on for my first project. I plan to go with a natural finish and no pickguard. I found full-scale technical drawings of the J Bass somewhere online and have already prepared an MDF template to use for routing the shape of the body.

I purchased a rough cut ash slab in August, and it finally got dry enough to work with last month. It's 56" long, 1 3/4" thick, and averages 14" wide, I'm hoping to be able to cut two bodies out of this in case I have problems. The width is just barely enough for a single-piece body. You'd think there would be plenty of length for two bodies, but now that it has dried, it has a few issues.

It's bowed on both length (about 3/8" gap at the middle) and width (about 1/8" gap at the middle. I should be able to correct this in the flattening process, but it means losing some thickness. It also has a bad check (crack) at one end about 12" long, a bad knot and additional checking at the other end, and some smart imperfections in the middle.

I figure I have two options:

1) Cut out two single-piece bodies as originally planned, cutting around the worst cracks and filling in the knots and other lesser cracks with epoxy as needed.

2) Cut the board lengthwise and get several smaller pieces (probably three each) to glue up into the two bodes, allowing me to not have to work with any of the imperfections.

So that's my first question: which of these options would be recommended by those who have done this before?

I'm documenting progress on my Instagram (https://www.instagram.com/sethgali/) if you'd like to see examples of the issues with the slab. I'm not fishing for followers, I've just already started the process there.

I'm open to any and all advice on this project, so please fire away. Thanks in advance for your help.

Seth

hello and welcome aboard.

sounds like you've done some good homework.  I think a jazz bass is a great place to start because it is a well documented build. 

afa blank... I love one piece, but also hate the idea of wasting wood.  Perhaps you can get one 1 piece and two pieces that you glue up?  afa thickness... I generally plan to loose 1/8" flattening things so if all goes well that puts you in the 1 5/8" range which is pretty common for fender.  If you've got a lot of bow you might find yourself too much lower than that... you can always consider adding in a drop top. 

Ultimately, you just need approx 1/2" below the neck for mount and 5/8" depth for pickups so in theory you could go for a thinner guitar if you wanted.

nice looking ash.  I highly recommend you update this site with your pics and just link/copy to instagram... you'll find lots of great folks that will be willing to help you and I'm sure most of us would appreciate being able to watch your progress. 

hard to really see any major issues on that slab.  Voids - as long as they aren't structural, can be filled and personally I like to see little imperfections in a guitar, but ultimately you have to decide.

 

one piece of advice I'd give is to spend $20 and get a postal scale... that way you can keep a close eye on weight as for me that a big consideration.

Get your templates perfect and check them with your fingers... lot easier to get mdf smooth than 2" of hardwood. 

look fwd to your progress, and hope some of this helps.

[sethgali]

tThanks for the great input. Good to know about the required thickness. That's something I was going to investigate as I got closer to those parts. I hadn't thought about dressing the top. That could be an opportunity for a nice show piece of wood. I'll keep it in mind.

As far as the "blemishes" go, I'm not averse to some character, I just want to make sure they aren't going to be a problem structurally. I don't think those smaller knots should be a problem, but I am worried about the larger knots and checks.

I hand-sanded the template pretty thoroughly to even out all the transitions, but it's worth hitting again. I know that the better the template, the better the final cut will be. And I do have a scale handy to check on the weight. What is considered a good target for that?

I've attached some pics of the serious problems. The first is a large check in one end. The other is a significant check within the heartwood near the other end. There are a couple of big knots at the same end as the second one, but any layout I've tried so far avoids them. For higher res pics, I created an album on Google: https://photos.app.goo.gl/WninU6UtABRt5L6n9

I tried some layout options and it appears the only area I can fit the full width of the body is the end with the check in the heartwood. It would also fit at the other end but not clear of that bad check. It also seems that due to the position of the bad check, there doesn't seem to be any way to get a second body out of this slab, even in pieces, which is disappointing.

So how bad is that check in the heartwood? I can't tell how deep it is. I don't think it goes all the way through, so maybe it's not a problem? There is a very slight check on the other side in that vicinity, but the orientation is different than this side so I don't think they're connected, but I could be wrong about that.

I can cut out enough pieces to do one body and not worry about any of the major flaws, so that's still an option. And I'm sure I can find a use for the leftover wood, just not in a guitar project.

Maybe I'm just overthinking it and over-worrying and just need to bite the bullet and do it. Any further advice is welcome.

Seth

[willliam_q]

Hey Seth, welcome to the forum.  
 

the checks in the wood can be dealt with but As a first build I personally would look for a piece of wood that had no checks.  However I’m not very experienced myself at guitar making so don’t take my word for it.

Ben at crimson guitars is fond of using similar woods with cracks in them, have a look at crimson guitars on YouTube.  He has been known to hold two pieces together with threaded rods!  Also, there are plenty of videos out there where guitars have been made with say skateboard laminates and crayons etc.  These guitars have been flooded with epoxy to make a solid body and perhaps you could do something similar here.

[Bizman62]

Hi Seth and welcome to the addiction!

As @willliam_q said, cracks and knots can be used for adding interest to the build. Rods through the entire body to fix a crack right in the middle may not be the ideal solution. Filling with epoxy/resin might work for bigger holes, a scarf joint like the ones April Wilkerson made to solidify her guitar while on a course at Crimson is also a valid option. The latter is a widely used technique in a variety of single piece wooden constructions, I first recall having seen it in a video where they made expensive design dining room tables without any screws or glue with a single piece top! Think about the hidden tensions that can lurk in a four inch thick six foot wide and a dozen feet long piece of wood that has withstood all kinds of conditions for hundreds of years...

Cutting along the imperfections and gluing the "good" pieces is also a valid option. Done right that would also help with cupping and twisting as there will be opposite forces overruling each other.

Re cupping during the drying process: Did you turn the blank upside down every now and then? And did you have slats under the blank to ensure proper airflow on both sides? If not, turn the cupped side down for a few weeks to see if it straightens. The cupping can indicate that the upper side is drier, having shrunk more than the down side.

 

[Andyjr1515]

Hi, Seth

Welcome to the forum   Another sax player!  Excellent

Not much to add to the above other than to ask - is the timber now fully seasoned?  That is, has it stopped moving? 

If it is and it has, then no worries.  The body of a bass is pretty much just a convenient place to hold the bridge and pickups - you can take HUGE liberties with it.  You can fill the cracks or just leave them - although I would personally 'wick' thin CA into where the crack disappears to prevent it spreading further.

If it isn't fully seasoned, however, I would personally not use it yet.  It will keep shifting and that will affect everything. 

The neck...also a completely different issue.  That does have to be the right grained timber, seasoned and without structural flaws.  I presume you are using a different type/source of timber for the neck?

[mistermikev]

15 hours ago, sethgali said:

tThanks for the great input. Good to know about the required thickness. That's something I was going to investigate as I got closer to those parts. I hadn't thought about dressing the top. That could be an opportunity for a nice show piece of wood. I'll keep it in mind.

As far as the "blemishes" go, I'm not averse to some character, I just want to make sure they aren't going to be a problem structurally. I don't think those smaller knots should be a problem, but I am worried about the larger knots and checks.

I hand-sanded the template pretty thoroughly to even out all the transitions, but it's worth hitting again. I know that the better the template, the better the final cut will be. And I do have a scale handy to check on the weight. What is considered a good target for that?

I've attached some pics of the serious problems. The first is a large check in one end. The other is a significant check within the heartwood near the other end. There are a couple of big knots at the same end as the second one, but any layout I've tried so far avoids them. For higher res pics, I created an album on Google: https://photos.app.goo.gl/WninU6UtABRt5L6n9

I tried some layout options and it appears the only area I can fit the full width of the body is the end with the check in the heartwood. It would also fit at the other end but not clear of that bad check. It also seems that due to the position of the bad check, there doesn't seem to be any way to get a second body out of this slab, even in pieces, which is disappointing.

So how bad is that check in the heartwood? I can't tell how deep it is. I don't think it goes all the way through, so maybe it's not a problem? There is a very slight check on the other side in that vicinity, but the orientation is different than this side so I don't think they're connected, but I could be wrong about that.

I can cut out enough pieces to do one body and not worry about any of the major flaws, so that's still an option. And I'm sure I can find a use for the leftover wood, just not in a guitar project.

Maybe I'm just overthinking it and over-worrying and just need to bite the bullet and do it. Any further advice is welcome.

Seth

(see what I told you about nice folks chiming in? keep in mind that you should always weight responses... there are many veterans here and while I've been a woodworker all my life... I am only on builds 5/6/7 so keep that in mind)

while I think you could probably just fill those end splits with epoxy... myself I would avoid them.  the most expensive part of a guitar is your time... and if they decide to start running further that'd suck... just not worth the risk to me.  Then again you see lots of folks using just a few sticks and the rest of the body is epoxy so... def could be done.  I guess once you have epoxy in there it's probably not going to be able to run.

What about taking your template, scaling it down a few percent, and making the center wood work?  I know you pretty much got yer template done... perhaps do this one as a 2 piece with plans to do a smaller 1 piece later?  well, something to think about anyway.  My first build was a p bass that I scaled down a hair... then again it was a 32" scale.

afa weight... for me... the lighter the better but my end goal is generally in the 7-8lb range.  that's going to be about a 65/35 split between body and neck... so IME you really need your body wood to be 4.5-5lbs or less as the bridge/pickups/finish is likely to add a pound. 

 

[sethgali]

@willliam_q Oh yeah, I'm a big Crimson Guitars fan. And while I don't love everything Ben does, it certainly shows just how far outside of the box you can go and still have a functional piece of art. For a first attempt though, I'm going to try and avoid the checks as much as possible.

@Bizman62 I watched April's build with Crimson (also been a fan of her work for years), but don't remember her using a scarf joint. I'll have to go back and look again. I do appreciate a good bit of joinery. Unfortunately, I stored the slab standing on end while it was drying. I'm guessing this is the largest cause for the cupping.

@Andyjr1515 Woohoo!  I last measured the moisture content at the beginning of December and it was around 5.5%. Started at 15% when I got it in August. I suspect it's mostly done drying at this point (or maybe I'm too impatient to wait any longer). The guy I bought it from had it in his garage, and it's been in mine since I got it. I plan on using a prebuilt neck. Not ready to tackle bulding one from scratch on my first project.

@mistermikev I'm an IT guy for my day job so I look at a lot of forums. I could tell pretty quickly that this was a good one. Thanks for the advice on weight. I was thinking about the option of using the narrower portion of the slab and just shaving a bit off the edges, just hope it won't make the overall shape look too unbalanced.

Right now, I'm leaning towards staying away from that bad check in the end entirely. The one in the middle of the heartwood at the other end of the slab (which actually starts about 13" in from that end), while it looks potentially significant, seems like an acceptable risk. It's location would put it right in the middle of the body, which seems less critical than say near the neck pocket. I'll have a better idea how deep it is once I surface and flatten the rough cutout. Then I can stabilize it with either CA or thin epoxy. Does that sound reasonable?

Thanks for putting up with my rambling and the great responses. I don't know anybody to talk directly to about these things so I'm basically thinking out loud and looking for advice here. I'm sure once I build a dozen of unplayable instruments, I'll figure out what actually works. 

[Andyjr1515]

10 minutes ago, sethgali said:

I'm sure once I build a dozen of unplayable instruments, I'll figure out what actually works.

I wouldn't bank on it.  I still haven't figured it out yet 

[Bizman62]

51 minutes ago, sethgali said:

I watched April's build with Crimson (also been a fan of her work for years), but don't remember her using a scarf joint.

Ouch! Foreign language, poor memory, wrong word. Bow ties! Bow ties! That's what I meant.

[mistermikev]

50 minutes ago, sethgali said:

@willliam_q Oh yeah, I'm a big Crimson Guitars fan. And while I don't love everything Ben does, it certainly shows just how far outside of the box you can go and still have a functional piece of art. For a first attempt though, I'm going to try and avoid the checks as much as possible.

@Bizman62 I watched April's build with Crimson (also been a fan of her work for years), but don't remember her using a scarf joint. I'll have to go back and look again. I do appreciate a good bit of joinery. Unfortunately, I stored the slab standing on end while it was drying. I'm guessing this is the largest cause for the cupping.

@Andyjr1515 Woohoo!  I last measured the moisture content at the beginning of December and it was around 5.5%. Started at 15% when I got it in August. I suspect it's mostly done drying at this point (or maybe I'm too impatient to wait any longer). The guy I bought it from had it in his garage, and it's been in mine since I got it. I plan on using a prebuilt neck. Not ready to tackle bulding one from scratch on my first project.

@mistermikev I'm an IT guy for my day job so I look at a lot of forums. I could tell pretty quickly that this was a good one. Thanks for the advice on weight. I was thinking about the option of using the narrower portion of the slab and just shaving a bit off the edges, just hope it won't make the overall shape look too unbalanced.

Right now, I'm leaning towards staying away from that bad check in the end entirely. The one in the middle of the heartwood at the other end of the slab (which actually starts about 13" in from that end), while it looks potentially significant, seems like an acceptable risk. It's location would put it right in the middle of the body, which seems less critical than say near the neck pocket. I'll have a better idea how deep it is once I surface and flatten the rough cutout. Then I can stabilize it with either CA or thin epoxy. Does that sound reasonable?

Thanks for putting up with my rambling and the great responses. I don't know anybody to talk directly to about these things so I'm basically thinking out loud and looking for advice here. I'm sure once I build a dozen of unplayable instruments, I'll figure out what actually works. 

"I'm an IT guy for my day job " - I'm sorry to hear that... we've reached our quota on IT guys in here.  pretty sure everyone that freq this website is in IT/Dev!  hehe.

afa narrow... I guess it all depends on how close it is.  You could do a 1.1 piece... just use a small edge piece glue on.  Might  be a nice option. 

Seems like you are on the right track and in good hands with all the input above so... you got her otter.

[sethgali]

1 hour ago, Bizman62 said:

Ouch! Foreign language, poor memory, wrong word. Bow ties! Bow ties! That's what I meant.

Heh, and all this time I always called them "dutchman" patches.  But yeah, that's not a bad idea. Thanks!

[sethgali]

1 hour ago, mistermikev said:

"I'm an IT guy for my day job " - I'm sorry to hear that... we've reached our quota on IT guys in here.  pretty sure everyone that freq this website is in IT/Dev!  hehe.

afa narrow... I guess it all depends on how close it is.  You could do a 1.1 piece... just use a small edge piece glue on.  Might  be a nice option. 

Seems like you are on the right track and in good hands with all the input above so... you got her otter.

Something about IT guys (and gals) I guess. We think we can do anything.  Now that you mention that option, that's an easy fix. I can probably do that one almost seamlessly with the wood grain, too. You'd think I would have thought of that one. Thanks!

[mistermikev]

1 hour ago, sethgali said:

Something about IT guys (and gals) I guess. We think we can do anything.  Now that you mention that option, that's an easy fix. I can probably do that one almost seamlessly with the wood grain, too. You'd think I would have thought of that one. Thanks!

happy to be of some use.