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Amateur needs advice
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10101&t=18425		 Page 1 of 1
Author:  mhh [ Sun Aug 17, 2008 4:25 pm ]
Post subject:  Amateur needs advice
I recently completed the construction of a ukulele kit from Steward-McDonald and there are some things about the finished product that I would like to change but do not know how to go about doing so. The action of the strings is slightly too high at the nut, but at the bottom of the neck it's just ridiculously high and almost unplayable. The bridge is as low as it gets, and I think the problems with the ukulele's are because the neck is at an angle pointing slightly higher than the body (kind of like the opposite of a violin, but much less extreme) and I think it there was some way I could mold the neck down than my action problems would be lessened. Also, there is a bad buzz on the 6th fret for the 2nd and 3rd strings where I hammered in one of the frets too low, and I'd like to know if that problem is fixable or if I just have to avoid playing those notes. Thank you for reading, and thank you in advance for your advice.

Here is a picture so you all can see what I'm talking about

http://img135.imageshack.us/my.php?image=photo36by4.jpg


~Matt, New Jersey
Author:  Rod True [ Sun Aug 17, 2008 4:43 pm ]
Post subject:  Re: Amateur needs advice
Matt, first welcome to the OLF.

What you've described is called the set of the neck or some call it the neck angle. When you are fitting the neck to the body you need to ensure that the neck is set so as the plane of the fretboard is above the bridge (without the saddle) at some determined amount. I've not built a uke but my guess is that it's very similar to that of a guitar. So when I set my neck, I try and get the plane of the fretboard **WITH FRETS INSTALLED** to be 1/16-1/8" above the top of the bridge.

The way to do this is to remove small amounts of material (sanding is the best way) from the back of the neck heel (the side which bears against the body). If you need to get the plane of the fretboard down (this brings the neck forward) you would remove material from the upper portion of the heal (from the fretboard down) and feather it along the length of the heel check. If you need to get the plane of the fretboard up (Which is what you need to do I think) you remove material from the lower portion of the heel (from the bottom of the heel) and feather it along the length of the heel check.

This is an exagerated detail from your picture

Attachment:
photo36by4.jpg


As for the low fret, take a straight edge and see how much clearance there is between the low fret and the two on either side of it. If it's really low (like 0.015" or more) you should remove that fret and install another one, if it's not to low than leave it in and than you should level the frets (search for fret leveling, it's been discussed here often) so that no one fret is lower or higher than the other's, this should eliminate the buzzing. But you need to set the action first which is best done by setting the neck correctly.
Author:  RodN [ Mon Aug 18, 2008 8:30 am ]
Post subject:  Re: Amateur needs advice
I think I can see where your problem has happened. I have built a few of these Stewmac kits.

The kit is designed that the neck set angle is at zero degrees. That is, when the bare neck (without the fingerboard) is placed against the body face down on a flat surface, the top of the ukulele (the soundboard) is dead flat and the neck face dead flat in relation to eachother. The heel is already pre-shaped to match the top of the body.

Like this (this one is a Stewmac kit, but with added binding and purfling)

Image

Image

You see... the body and the neck are face down on a flat surface, and this is the "zero angle" of the neck set.

Now, that zero degree neck set angle can only be achieved if the top end of the body is built vertically. It looks from the photo that yours isn't. Therefore, when you fitted the neck, it is not in the same plane as the body top.

This exaggerated drawing shows what is happening on yours.
Image

In other words it is a compound error... if the neck block wasn't dead vertical, then when you glued the sides to it, they would not be vertical either. Hence the top end of the uke isn't vertical (shown by the red line in my drawing). Then when the neck was fitted, its face isn't vertical either. That is the result of your high action.

See the photo by "Rod True" above... his red line shows the problem too.

A little "bodge" was needed when you set the neck in place to allow for that slight angle misalignment. This still could be done if you can get the neck off. Wood needs removing from the business face of the heel (where it meets the body). i.e. at the narrow end of the heel face. That would bring the neck (fingerboard surface) back into alignment with the top face of the body.

Rod
Author:  RodN [ Mon Aug 18, 2008 9:11 am ]
Post subject:  Re: Amateur needs advice
An afterthought... and where the problem really originated....

You assembled a jig, as per the Stewmac instructions, right?
One like this:
Image

Can you see what would happen if the upright at the neck block end (on the left) wasn't dead vertical to the base plate? Yes, the neck end of the body would be tilted over slightly. Then everything goes pear shaped from then onwards.

Don't let mistakes put you off !!
We all make them, and invent interesting "bodges" to overcome them.... and then try not to make the same mistakes again.

The Stewmac kit makes a really good ukulele! And it sounds great too.

Rod
Author:  mhh [ Wed Aug 20, 2008 12:13 pm ]
Post subject:  Re: Amateur needs advice
Alright, so I understand my problem with the neck. However, is there a way I can sand it down to a proper angle now that it's already glued on? Also, if I do this and reglue it somehow, will the intonation be incorrect since the bridge is already attached to a place that's correct in relation to the current neck angle?
Author:  Michael Dale Payne [ Wed Aug 20, 2008 12:52 pm ]
Post subject:  Re: Amateur needs advice
You could remove the frets and nut and sand the fretboard to the proper back angle but will end up with too thin of a fretboard at the nut end to install frets. . It should not be to dificult to remove the fretboard and neck and reset it the proper way.
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