Neck set - bridge height question

[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.

[Ken Smith]

Interesting Math you speak of. For the record, I have had basses with all kinds of necks over time and never has a Neck Heel been broken in my possession in about 45 years.

The Old English bass was most likely a Blockless neck originally but more of a Gamba style construction and not the more common German style. It was later converted to a Dovetail when a Block was added but some of the old Blockless tab was left in. Now it has a deep mortise joint in the modified block.

The Martini, Gilkes and Hart are all out about 35-36mm from the Top. The Old English is out at 46mm. The Loveri came and went as-is, never altered under my watch. The Shoulders helped that despite it being a long bass. The Mougenot needs a Neck Graft as the current neck is thin and bowed forward as well as being an Eb-heel. The overstand is fair at best but with a Graft I can shorten the string length and make it a D-heel. Maybe a few MMs more on the 'Stand or so. The other Bass is an old Neapolitan Bass that is in restoration and will get a graft as well for more reasons than one. That bass and the Mougenot already have added buttons in the heel and need replacing besides. The Storioni Neck is already out of the bass and the Scroll on a shelf at Arnold's. The Block area will be Cut and the new lower Button will be cut and shaped from the existing Back. The Block will probably get beefed up inside as well like was done with both the Old English and hart Basses during their restorations in place of an entirely new Block.

I think the pictures show about how deep or shallow the Necks are set into the Block. Three of the Basses have yet to be restored with new Neck Grafts. Three out of four of the restored basses had Grafts done in the process. The Gilkes Neck and Scroll are still one piece. That had a tiny Button added that moved it from maybe 10-15mm out only but also had a pitched ebony ship under the fingerboard. The Shim Button were removed and a longer button attached put in to help push the Neck out about another inch along with a new FB.. The results were night and day as far as playing over the Shoulders.

My personal test for playability on a bass is the opening of the Dragonetti as well as the harmonic parts in the first movement. That takes you up, down and across quite rapidly as well as playing past the fingerboard on 3 strings hitting the harmonics. This is basic I think for judging the playability of a bass in regards to reach and overstand.

[Matthew Tucker]

Interesting. So you are going to cut the back of the Storioni to fix this



so that the new button is made from the intact back wood, and including the centre stripe, then re-purfling??

Are you grafting the scroll, or using the existing heel?

Are you also cutting the front?