Dovetail neck join

Aerdna · #1 08-05-2008, 11:40 AM

Hi everyone,

I noticed a lot of basses with a dovetail neck joint. My bass (cheap no name Romanian) has one too. If I wanted to reset the neck, I can imagine a major pain in the butt trying to separate the neck from the block. I would also think it's impossible to do it without damage. What methods do people use to separate dovetail joints? Once the neck is off, could the male dovetail be converted to a "straight", regular insert?

Thanks!

Aerdna · #2 08-08-2008, 05:37 AM

Anyone? Please?

**Matthew Tucker** · #3 08-08-2008, 05:49 AM

With a few cuts, a lot of patience and steam you can persuade the joint to come undone. You'd need to separate the button from the back of the neck, then inject steam and hot water into the joint to sften and wash out the glue. You'd probably need to take the fingerboard off to be able to get at the work easily.

You can convert the neck joint to a standard joint but it's fiddly work. You would need to fill in the dovetail with fresh wood, make new clean flat tapered surfaces around the neck root, and then cut out the block to fit.

Aerdna · #4 08-08-2008, 07:39 AM

Thanks a lot Matthew. I already separated the button from the back. Also, the top is actually off because of other repairs. Next, I'll try to remove the fingerboard, very carefully. I'm going slow and taking my time to think about how to approach things. I need to figure out how to inject steam. I had read about someone (i think it was here on TB) using an espresso maker. We have lots of those here in Italy!

Jake deVilliers · #5 08-08-2008, 09:20 AM

If you have the fingerboard off you can inject steam into the dovetail to loosen the glue.

I use a little Mr Coffee with a rubber hose on the milk frothing attachment and a volleyball inflating needle, mostly on guitars, but basses too. Kay dovetails are just like big Martins!

I use a 5/64" drill bit to get the needle where I want it if there is no gap.

Be patient, it takes a long time to reach all the glue and release it.

Bob Branstetter · #6 08-08-2008, 09:52 AM

StewMac has a nice steam hose and needle that works great with a Mr. Coffee or similar espresso machines. It won't eliminate the possibility, but it will help prevent burning yourself with the steam under pressure

Aerdna · #7 08-08-2008, 01:15 PM

Thanks so much Jake and Bob. I know better what to do now. I'll try to go slow and be patient. This could also be therapeutic for me as I'm not a patient person by nature

ctregan · #8 08-08-2008, 03:00 PM

I have used vinegar before to loosen up the glue, just make sure you do not get any on surrounding parts of the bass or the ribs and block could come undone.

Here is a steam hose I set up; hot plate, pan with water, plywood top with pipe fittings and hose. Be careful, the steam gets really hot! Burn your hand hot!

Good luck!

Aerdna · #9 08-09-2008, 02:56 AM

I like your setup, good idea!

Bob Branstetter · #10 08-09-2008, 09:05 AM

It's a good idea to keep your heavy rubber hose as short as is practical for the job you are doing. A lot of the steam will condense back into hot water inside a long hose. You want to get steam into the glue joint, not a lot of hot water.

If you need a longer hose, you can make a simple in-line water collector out of a glass gar with a metal screw-on top. You can get (threaded one end, barbed on the other) brass fittings at your local hardware store the same size as the inside diameter of your hose. Fit them into 2 holes in the screw-on top. The steam comes in one side and goes out the other. With luck, most of the line condensation collects in the glass jar and not inside your project.

Be careful with live steam. It can be hazardous to your skin.

Aerdna · #11 08-09-2008, 04:34 PM

That sounds very ingenious! I'll also keep in mind your (and ctregan's) words of caution, thanks.

**Matthew Tucker** · #12 08-10-2008, 12:34 AM

i don't think hot water will hurt the bass, just that steam is hotter and more penetrating.

Bob Branstetter · #13 08-10-2008, 10:17 AM

Quote:

Originally Posted by Matthew Tucker

i don't think hot water will hurt the bass, just that steam is hotter and more penetrating.

I prefer to inject the pressurized steam into the dovetail joint with a long needle so that I can get the steam where I want it. There will always be some liquid water in the joint as a result of the steam cooling while it is inside the bass, but I think it is important to minimize the amount of the water inside the bass. You want to prevent the water from getting into places where you don't want it such as into the glue that holds the neck block in place or into the plys in a laminated instrument. In addition to this, if both wood parts of the dovetail joint get excessively wet, the wood will swell and make it even more difficult to remove the neck.

Many years ago, a luthier told me that he had been removing guitar necks by injecting hot water into the joint with a dental "WaterPik". I made the mistake of trying that on a bass one time and I just about never got that neck out.

One steam tip (that may seem obvious to most people) is that you need to position the bass so that water will drain out to the front and not build up inside while you are working on it (i.e. don't lay the bass on it's back).