Neck set - bridge height question

[Matthew Tucker]

Originally Posted by Ken Smith

30mm overstand? Is that what you have there? Quite low in my book. Most builders today use from 35-40mm.

Well, it all depends on the bass, doesn't it? Ken's bass is a cornerless model with sloping shoulders, already easy to reach around into TP, so I don't think he necessarily needs a higher overstand.

My cornerless has 30mm and it's perfectly adequate. any more and it would start to look odd ...

Having said that, its good to start with a deeper overstand. You can always reduce it when fitting the mortise.

[Ken Smith]

Originally Posted by Matthew Tucker

Well, it all depends on the bass, doesn't it? Ken's bass is a cornerless model with sloping shoulders, already easy to reach around into TP, so I don't think he necessarily needs a higher overstand.

My cornerless has 30mm and it's perfectly adequate. any more and it would start to look odd ...

Having said that, its good to start with a deeper overstand. You can always reduce it when fitting the mortise.

It's not just the overstand Matt. In order to achieve the desired Bridge height, you will have to pitch the neck more in angle to the Top with a lower overstand. My Gilkes had about 13mm when I got it and no one complained about that for 50 years. I was on my Toes trying the reach the harmonics at the end of the fingerboard. Also, the tension feels better now with the increased overstand and decreased angle to the Top.

I guess a player can notice this best when he has had a bass for awhile, gotten used to it, had it modified and then compares the difference of before and after. In making the bass new and just picking a singe design of overstand and bridge height, there is no comparison to the playability not having tried it with other measurements.

Therefore, playing basses before and after modification is the best way in my opinion to form judgment on this subject. Not being the Luthier that does the job has no smaller amount of awareness than the the player that lives with the results. Actually, the player might notice the changes even most being more familiar with the bass overall than the Luthier.

As you may know I have a fine old Cornerless bass and regardless of the shoulders, the larger overstand makes it easier to play the upper positions. I played the Pulcinella suite and solo within days of purchasing the attr. Storioni and that is moving from a 41" string length to over 44". If not for the combined ease of playability (and my love for the sound of this bass despite the finger stretch) I would not have been able to use this Bass in concert at 44". Actually, prior to bringing it in for restoration I used it for several concerts. If the Bass had a workable c-extension then I might have used it one all of my concerts but the condition of the bass was not getting any better so I retired the bass to Arnold's shop until it's fully repaired and modified with a shorter string length.

[Matthew Tucker]

Originally Posted by Ken Smith

Therefore, playing basses before and after modification is the best way in my opinion to form judgment on this subject. Not being the Luthier that does the job has no smaller amount of awareness than the the player that lives with the results. Actually, the player might notice the changes even most being more familiar with the bass overall than the Luthier.

Well, I guess that means you're right then. How silly of me to even think that it might depend on the bass ...

[Craig Regan]

With a larger overstand, should there be any added heel reinforcement?

Is this potentially a weak spot for a bass neck?

[Matthew Tucker]

A larger overstand does put a greater strain on the neck joint, due to increased leverage. But it's only an increase of around 5%-8%, and unless your mortise is very shallow, I don't think you'll need any extra reinforcement, even at 40mm overstand. You could make your mortise a couple of mm deeper to add glueing surface to compensate.

[Ken Smith]

Originally Posted by Matthew Tucker

A larger overstand does put a greater strain on the neck joint, due to increased leverage. But it's only an increase of around 5%-8%, and unless your mortise is very shallow, I don't think you'll need any extra reinforcement, even at 40mm overstand. You could make your mortise a couple of mm deeper to add gluing surface to compensate.

Matt, I had a question on this after listening to both your opinions and Arnold's on the strength of the lower Heel. My question is as you just mentioned, does the depth of the Heel into the Block itself make up for the possible strength lost when the Heel is cut Lower 'above' the Block?

I will now post a bunch of pics and solicit your opinion on Neck Heel height above, depth in the Block and Overstand as well. Some of these pics are the Basses as I received and left them, some waiting to be restored and some have been restored with either a new Graft or just the Neck itself moved out.

[Matthew Tucker]

Well, from the pictures we can't tell the condition, style or depth of your neck mortises, or what the existing overstand is on each bass.

So what can i postulate?

- the Gilkes has a full length heel with little upper rib taper. Increasing the overstand from 30mm to 40mm would decrease the gluing surface by 5% and increase the leverage on the joint by a similar factor.

- the Hart has a very short heel. Increasing the overstand from 30mm to 40mm would decrease the gluing surface by nearly 8% and increase the leverage on the joint by a similar factor.

- the Storioni has only slightly more heel length than the Hart, but the mortise looks fairly shallow compared to the others, and the button appears just tacked on, so that 7-8% may be more significant.

- the Olde English has what looks like a dovetail mortise. That would change things again, if resetting the overstand was possible using the original dovetail, ie: not converting to an italian heel.

I would hesitate to make any generalisations, however I think a good luthier would naturally compensate for any changes in geometry (overstand or angle), and the reset, if done well, would not compromise the strength of the joint.