Gluing a solid body

[johnuk]

The body is Sapele, African mahogany. It was planed at the wood store. I will be using two pieces to form the body, they are 6x2". I gave the edges to be glued a sand with some 80 grit paper, then sanded them with some 400 grit.

I have had expirience with woods like pine, where-by I could cut a really bad join then squeeze it into a nice clean looking affair with sash clamps and a vice. Obviously this will not be the case with 2" thick hardwood! But there is a very tiny point of light occasionally down the seem with the blocks just resting on top of each other. By tiny, I mean sub 1mm, only just enough for light to get thru. I've had a go at sanding it out but it's too small to keep track of really.

When I glue the blanks I am going to be using a type of PVA all weather wood glue which I'm going to be rubbing into the grain of the join. We have some very expensive looking sash clamps at school I'll use to pull the wood together for a day or two while it cures. The question I have is, will I be able to pull this tiny gap shut with the pressure from the sash clamps?

I am asking this because I am used to working with metal and so I'm used to a totally different set of rules. With a 2" block of steel, there is no pulling together to speak of. My only other expirience is with pine, which the clamps could nigh on crush. Does wood of this type and size have any degree of play?

[Brian]

My general thought is if you have to bend or pull the joint together to begin with it more then likely will be under stress to seperate no matter how hard it is glued together.

Might not make a diffference in strength at first with todays modern glues but over time something could eventually give even if it's the grain beside the joint.

Just a thought

[krazyderek]

if we're talking little pin hole size gap that's only a cm or 2 long, i wouldn't worry, just clamp all the areas around that tighter then the gap area. that should compress the wood around it and bring it level, if you clamp the gap area hardest that's actually going to bend one of the peices of wood and as brian said that may lead to eventual boos boos down the road.

[Setch]

Warning.... wood working fascist posting

The purpose of clamps is to hold two pieces of wood together whilst the glue sets - it is not to squueze them together to and close any gaps. If you want this joint to look good, get it so it is light tight - ie: No light whatsoever shows through if you hold the joint up to the sun. Over clamping is not a solution to a poorly fitting joint.

I true up two piece blanks with a handplane, and fine tune with 80 grit paper on a piece of plate glass, and a cabinet scraper. You can also the edges to be joined through a well setup jointer, which should leave them perfectly flat and square, and allow for a perfect joint.

Get this joint right, because anything else will look halfarsed, and possibly be prone to failure later. I'd also advise you to use titiebond original rather than any all weather glue. Waterproof PVA's are sometimes less strong than common titebond, and can fail to dry in a large joint, leading to creeping and glue failure over time, especially in hot weather. This, coupled with the fact guitars aren't intended to be waterproof eliminates any benefits of all water resistant glues. Also, avoid titebond II for the same reasons.

[Jehle]

This, coupled with the fact guitars aren't intended to be waterproof eliminates any benefits of all water resistant glues. Also, avoid titebond II for the same reasons.

Avoid Titebond II? I'm not sure I understand.

If the guitar absorbs moisture, the Titebond II bond would not fail. The wood would be more prone to fail first.

[Setch]

Titebond II is not a good choice for guitar builders. It simply doesn't set as hard as regular titebond, and a number of builders have reported joints glued with it creeping or failing. I've heard of tops laminated with it coming unstuck, and revealing unset glue after several weeks.

Something titebond did to the formulation to improve the water resistance reduced it's strength and changed it's cure characteristics. With this in mind you have to ask what advantages are provided by Titebond II over original - there are none except it's water resitance, which is a non issue on a guitar unless you plan on using it as a canoe paddle...

This information came from the mimf, and is based on the independant observations of many experienced builders over a great many years. I'm not saying T'bond II *will* fail, and if you've used titebond II previouisly you'll probably be fine, but I wouldn't advise anyone to use it given any alternative. Titebond original is a superior product which is just as widely available and no more expensive, so why risk a product which has a track record of failing in lutherie applications?

[daveq]

I'm not arguing for using Titebond II but after reading the mimf info I got the impression that each "common" glue had issues that made it not suitable for guitar building. I asked if I should be concerned since I built one using Titebond II and they said it would be fine. Maybe the person who told me that was wrong. I haven't seen any problems with it yet but who knows.

I'd really like to see some hard facts on this topic if anyone has them. The reports of the glue failing are reason for concern. It would be nice to know for sure.

The block plane or jointer seems like the right answer for the joint though.

[Setch]

Dave, are you a registered MIMF member? If so, browse the library for "Major problems with bottled hide glue and Titebond II" and "Titebond or titebond II" in the glues section. I won't quote directly, but the general perception is that titebond II leaves more visible glue lines, and doesn't set as hard as titebond original. The thread also discusses Franklin's liquid hide glue, and urges people to avoid it like the plague. I think it was actually the Liquid hide which never sets, so you'll probably be OK with any guitars you've used titebond II on already. That said, I wouldn't use it if you don't have to - it isn't a dissaster waiting to happen, but it simply isn't as good as Titebond original.

I used a specialsed aliphatic resin on my first guitar, and I much prefer titebond, which I've been using since. It has a really nice 'grab' time which allows you to position a joint and clamp it for 30 mins or so, rather than having to keep it clamped for hours.

[Jehle]

Well, I've had problems with Titebond II, that I can't deny. My first laminate job didn't cure, or stick to the body. But, I think that was more my fault than the glue. I used a contact adhesive on my next one and really love the results.

I'll experiment with Titebond classic next time and see what the difference is.

[daveq]

Setch, yes I am a member and I'll take a look. Thanks for the info. I've also requested some info from Titebond on this (who knows, maybe it will be worth it?).

The only reason I am asking all of this is so I can sleep at night knowing that my first guitar isn't going to fall apart on me (it's my favorite so far). The joints were very hard to see and I thought I was in good shape right up until I saw that chart in the mimf FAQ. That's when I asked about it and got that reply.

Jehle, what do you think happened with the first attempt?

[Brian]

What about Gorilla Glue?

[daveq]

Here's what the Titebond people had to say. Now I can see why people say it's OK for guitars already built but maybe try Titebond (original) for future guitars.

Thank you for your inquiry regarding Titebond II. Titebond II creates a

strong bond, but not one that is rigid or brittle. Titebond II can creep if

the glue line is under a long term high load. This creep could be

aggravated by high temperature and or a thicker glue line. A thicker glue

line would have less strength and be more capable of movement. The

recommended service temperature for Titebond II is between -20°F and 120°F.

At temperatures around 150°F, Titebond II can begin to soften and lose

strength. We would not expect a guitar assembled with Titebond II to creep

while stored in good conditions. I hope this information is helpful to you.

Sincerely,

Franklin International

[Jehle]

Jehle, what do you think happened with the first attempt?

I think it had to do with a few things:

I was rushing it.

I didn't sand the body enough to get down to raw wood. This was the kit that I got from Brian. Those kits have a great coat of sanding sealer on them.

I put on waaaaay too much glue. There were wet gloopy places still when I took the veneer off.

No surprise, I vow to never do that again to a guitar without experimenting first. For my last effort I experimented with Titebond II and DAP contact adhesive. See for yourself... Titebond bled through the wood like crazy (it's yellow), and the DAP held it firm and clean.

[westhemann]

man there is some good info in this thread!anyway from what i understand it is the addition of urrea which keeps it from setting tight.and i have been trying to veneer with it and have been having major problems.but i haven't noticed visible glue lines.i bough 2 bottles of it when i built my v but i will try the original in the future.

[johnuk]

That's a lot of replies! Thanks.

I have the blanks sitting beside me right now. I just did a bit of experimenting and can only just squeeze the red outer paper of a kit kat into the join (I mean, I have to wiggle it for a while to get it to fit thru). It stops about 5 - 6" from the ends. I am questioning if I should try to sand this kit kat wrapper sized piece away or leave it, since if I start sanding I may just add problems to one which doesn't seem to major to me. I may give it a try but I don't want to end up just sanding another one somewhere else.

As to the glue, the stuff I have is made by Evostick. I went for the weather proof glue figuring they could have only improved it over the normal glue, which otherwise appeared identical.

It has a firm bond time of 5 - 10 minutes! Full curing takes a few hours. And they suggest.... 'Assemble immediately, pressing pieces together lightly until a firm bond is achieved. For the ultimate bond sustain this pressure for several hours during drying'.

Apparently the glue is 'stronger than the wood itself!'. I will be holding Evostick to their word, and should the glue fail, I will be asking for them to sort it out!

I don't know if Evostick sells things in the US. Here they are famous for making epoxy everyone calls 'evostick'.

Should I sand? Or is the kit kat wrapper gap okay?

[budman68]

Honestly, I wouldn't sand a joint that is going to be glued. I have to agree with setch as I use a plane(or a cabinet scraper) to true up any surfaces that are going to be joined. I would invest in a plane rather than sand because sanding "rounds over" the edges unless you use a perfectly(and I mean perfectly!) flat block of wood that you could wrap the sand paper around to use as a sanding block. Even then, the results can be undesirable.

Dave->

[krazyderek]

i guess being cheap and going for the original titebond when i was buying supplies instead of paying a buck more for the titebond II actually payed off *pun pun*

[johnuk]

And so it begins!......

I took the blanks down to school this morning and glued them up. I'm not really there for any lessons now (too old ) so they sent me between classrooms to work while the kids were doing their othographic piccies of cars and things. The teacher's room I ended up in is a wood worker.

"Ooooo hardwood?!"

"Yes!"

"What are you making?"

"It's going to be..."

"A geetar?"

"Good guess!"

Pretty damm good considering it's just two planks glued together!

Trying to assemble the two glue dripping bits while man handling the sash clamps into place was fun. The kids didn't seem too bad. I've noticed a major group of asswipes beginning to come thru school now, the kind who are on Ritalin so their parent's don't have to speak to them. Unfortunately, I had to leave the body at the back of the room, so I'm just hoping they leave it alone. The glue had started to go off as I was putting it together, so it should be pretty firm now. It's sad when you have to hide your work in case someone brakes it for a laugh!

The glue was really thick compared to PVA. I had a brush to rub it on and it took a fair amount of it and some work to get it all over the join, as I say, compared to PVA.

Squeezing with the clamps wasn't an issue, since some kids have broken the handles off. So it was hand tight, tight enough that I could pick it up by the clamps though, and it didn't move.

I noticed a nice split in the end of the wood! I'm just really thankful I'd over ordered the blanks by about 10cm, and this one is on the end of the plank where he overshot. So I'll cut that chunk off when the glues set.

I'm just worried I've done something wrong now!!!!! It's like before you go on holiday. If only I had my own fully equipped wood working shop in the garage this wouldn't be a problem!!!

[daveq]

Very exciting time, huh? I hope it turns out to be alot of fun for you. After the glue has dried, how are you planning to smooth the surfaces (top/bottom)? Do you have access to a 13" planer? If not, a block plane will do a good job also.

I always wondered why non-guitar players always say guitar as "geetar"? I think that's what you said that the wood working teacher called it, right? That's always driven me nuts!

Dave

[Ford]

Git-fiddle?

[johnuk]

I have no idea about geetar. It's sad, but until I started playing I could never remember how to actually spell guitar! Maybe it's the same, if you don't play, it's easier to just spell it phonetically, geetar.

Once the glue has dried I'm going to sand off all the extra glue that came out of the join (It was far too tacky to wipe off even after I just put it on, and it's waterproof anyway!).

I'm going to setup a drill press in school with the depth stop at ~50% of the full body thickness, then drill many, many large holes with a spade bit in a 6" strip down the centre line of the body. The neck is going to be deep set, and since I don't have a router of my own, I'll probably end up trying to use the school's. Which means I have to limit the amount of time I'm using it for to the minimum. Added to that, the drill press is about 500 times quieter and will take out a lot more material in one go. Once it's all roughed out, I'll route the slot for the neck to sit in.

Then it, and the neck blank, are going off to a wood supplier near here. I'll get them to plane the body blank down so it's totally flat. The body top is going to profiled like the S series from Ibanez hopefully, but in the middle it'll need to be flat.

The neck and headstock will look a lot like an Ibanez's neck. I wanted to copy the one on my JS10th, because I like the feeling to be consistant when switching between guitars. I have a really beaten up Fender Squire, and I really don't like changing from the tight radius of the JS10th, with it's jumbo frets, to the Squire which in comparison feels almost flat and has almost no fret height (And to think I used to dislike the JS10th's jumbo frets!).

So anyway, hopefully the guys at this place will be able to do all the rebating on the neck, because it's a lot of work for me to do which is somewhat unecessary but could easily make things go horribly wrong.

The most annoying thing is trying to find somewhere to work, the rooms are usually VERY busy.

All the best,

John

(Who's excited because his 'real' floyd rose, tuners, ebony board, strap holders and other bits of junk are in the post to him all the way from the US! )