Neck block work

[Matthew Tucker]

This type. This is not the one I'm repairing though. All rubners i have come across have the same neck/rib arrangement with no ledge and decorative strip at the top and thus very thin mortise walls.

[Ken Smith]

Originally Posted by Matthew Tucker

This type. This is not the one I'm repairing though. All rubners i have come across have the same neck/rib arrangement with no ledge and decorative strip at the top and thus very thin mortise walls.

Looking over my Basses in the rack earlier I would say many of them are like this originally without any cappings but sunk in about 3/4" to 1" into the Block on average. Some much more but closer to an Inch on average. Personally I don't like the Neck too deep in as it plays easier with less Heel moving into thumb position.

If the Top is off you can do more. Blocks can be beefed up inside and the Neck sunk lower as well. Depending on how deep the Block is you can drop the Neck in a little lower if making a new Neck. If not, then you don't have room without altering the Back Button.

In this case you need to re-build the Block slightly and if need be, repair the Rib meeting the Neck. From the outside things are harder to make look its best but without seeing the actual bass, I can't say much more which way to go. If the Block is good, a slight re-build and a good re-fit should be just fine.

With the cappings you mention on some commercial basses, this is totally decorative. It is the bottom fit mainly with the block sides and Back supporting the fit that holds the Neck. How much platform across the sides of the Block till it meets the Rib has little to do with support. In this case, you need more Block inside the Bass to hold it all together.

Arnold is away this week but I am sure he will chime in on this. On just my basses alone that he has worked on, just about every method I mentioned above was done depending on what the Bass needed.

[Matthew Tucker]

Ken, there is plenty of block inside the bass and i don't need to set the neck deeper for scale length reasons. On basses where the walls of the mortise are this thin there appears to be little lateral strength, but perhaps this is unimportant, which is why i was after another luthier's view. I can easily rebuild the walls of the mortise but I was wondering how much strength this would really add, as I would have only a small glue surface to the actual block.

The "decorative" strip, in my view, caps perhaps 6-8mm of thickness at either side of the mortise and this thickness provides significant strength to the block area. This is how i build my neck blocks.

On this bass, the back is off, so there is scope for some extra work. I'll look forward to what Arnold and others might have to add.

cheers M

[Jeff Bollbach]

I always hate refitting a mortise like this as it seems as if there is not really enough gluing surface-especially if you have a lot of weight on the scroll with heavy German tuners or an extension. But if it is very well fit then it winds up being sufficient. Remember that by far the most important of the three gluing surfaces [sides, bottom, or button] is the button. Leverage!

[Ken Smith]

Originally Posted by Jeff Bollbach

I always hate refitting a mortise like this as it seems as if there is not really enough gluing surface-especially if you have a lot of weight on the scroll with heavy German tuners or an extension. But if it is very well fit then it winds up being sufficient. Remember that by far the most important of the three gluing surfaces [sides, bottom, or button] is the button. Leverage!

Jeff, what would be in your opinion the 'least' important surface then. the bottom or the sides?

[Ken Smith]

Originally Posted by wayne holmes

anyone ever use screws from block to heel?
if not - why?

I have seen it. More work fixing it from the screws than it took putting them in I'm sure. Bad idea. If someone did that to one of my Basses, that person would need to hide! A good joint with strong hide glue would work just fine.

Screws put in from Heel to Block is an emergency repair that ruins the integrity of the Neck. A neck graft would be needed in my opinion to un-do the damage as well as possibly needing a new Block as well. For a cheap school plywood bass it's like fixing furniture, a handy man repair, not a Luthier job regardless of who does it. If put in from the inside, either the same mentality or the person doesn't know how to fix the block or use glue.

What if a screw comes loose? What if a screw breaks because that was all that was holding the neck and it suffered more damage in handling breaking the screwed repair? Do it again with more holes, more screws? Junk on junk.

At that point, instead of screws you might as well try using 2-ton epoxy!

Wayne, are you asking about fixing a normal made carved bass or a cheap bass shaped object?

I just got in an old Mittenwald Bass c.1850 and the Block/Rib area is just like the Rubner bass Matt described. The difference is the age. This Bass has a button repair and wood plate overlay on the Back showing that it had past damage. Basses are big. They take hits and things break. No reason in my mind to stop being a Luthier and start becoming a handy man. Right?

[Jeff Bollbach]

The sides would be the next in holding power. I have taken out many a neck in which there was almost no contact between the bottom of the neck and the mortise yet it was still holding under tension. The leverage factor and also that the bottom of the neck is end grain adds to this being the weakest link.

Don't be such an elitist re screws. I've done it plenty of times-don't worry, not on your basses! ...and of course not on any carved bass but sometimes its the only cost effective way to get a Kay or something similar up and running. Generally you see only amateurs using metalwork but a skilled luthier can screw with quality.