angled endpin - drill endblock at an angle ?

[Damon Rondeau]

Nobody's talking sin and sandpaper, I don't know where that came from. I'm only saying I find it crude and unpleasant. I'll add expensive to the list, too.

Blades are more controllable and produce a nicer-looking result.

You'd think that, with even inexpensive reamers going for big dollars, someone would come up with an adjustable reamer. The cutting edges would only need a couple of degrees of movement. If there was a big market for luthiery tools, I'd bet that it would be done already. 'Course, the reamers wouldn't be as expensive in the first place under those market conditions...

Wasn't it Mr. Branstetter who used to turn the endpins to a precise fit?

[Silversorcerer]

Let's just skip the sandpaper issue for now;- it is at best a personal preference methodology thing or one of ingenuity vs. specialized equipment and no one is going to see inside the tapered hole unless it needs repair anyway. If you are patient with either process and don't get in a hurry and have accurate tools, I think a well matched reamer or sandpaper on the plug will do the job.

Rather, I'd like to return to the central issue of the thread concerning the structural integrity of the end block / end pin interface and the common use of spruce for end block material.
Arnold S.:

I install my endpins with a slight down angle which eventually becomes straight due to string pull.

This is a tacit admission that the spruce will distort eventually, that the maker anticipates it, that a perfect fit of the plug is, in that case quite irrelevant, and it is more important to compensate for the anticipated failure of the material by boring the hole off axis than to achieve a perfect fit.

Summarizing, first we have the lengthy defense of the use of a material possibly ill-suited for this purpose. Then a failed attempt to disqualify a suitable substitute (yellow poplar) coupled by admissions that harder denser woods (maple, mahogany, etc.) have been used successfully by other builders, and finally an admission of a work around method that allows stubborn builders to accommodate the use of traditional spruce. And all the while, the meaningless banter over blades vs. sandpaper, originally poorly fit sockets, when I'm going to finish a bass, etc. I think I'm quite done with this thread.

[Eric Jackson]

Originally Posted by Aaron Noguer

I wish Bob Branstetter was still posting around here.

I'd bet this thread is a perfect example of the reason he doesn't bother. Too much sanctimonious lecturing based on too much hypothesis and too little experience.

[arnoldschnitzer]

"Knowledge" triumphs over experience...

[Damon Rondeau]

There's no Triumph in this thread. Some Motorhead, maybe.

[Eric Jackson]

Originally Posted by Flamin' Condo

There's no Triumph in this thread. Some Motorhead, maybe.

Are you talkin' heavy metal bands or motorcycle/ automotive enthusiasts?

[myrick]

ahem, interesting diversion.

I've been offline for a few days since I first started this thread, and returned today to learn much valuable information about the specific gravity of tulip poplar and the philosophy of sandpaper.

anyway. . . .

anyone know who sells laborie pins ? google only shows me Slava, whom I have never dealt with before. any first hand advice on installing them (at an angle) ?

also, back to original query, is drilling a new hole at an angle (for laborie or whatever pin) okay ? sounds like this is all one does to install laborie pins. is it too much for the block (wood as yet unknown) ? 500 to 1 risk I can live with.
thanks

[Silversorcerer]

Erik Jackson:

Non- luthier- specific mechanical engineering stuff:
Having the point at which the end pin enters the bottom block directly above the point at which the tip of the end pin rests on the floor is the ideal situation. This will impart the least amount of levering or wedging force on the bottom block. An angled hole for the tail plug will accomplish this if you drill the hole at, say, 30 degrees from vertical then lean the bass back 30 degrees when you play. An offset pin like the Egg pin will accomplish the same thing without modifying the bass.

The worst possible case would be to have a conventional straight end pin extended a long way, then have the bass leaned back. This would put the plug a ways behind the floor contact point and the end pin would be acting as a lever in the plug.

Part of the answer depends on whether you are going to be leaning the bass back to play seated or keeping it vertical to play standing. As Erik points out, it is not a good idea to create a situation where in addition to the string tension the block also must withstand an additional levering force from the weight of the backward leaning bass on the extended pin. For playing seated, if the hole is angled so that the pin extends angled backward, this puts less stress on the block than a vertical hole with pin extended. If you are playing standing with such an arrangement the same angle introduces a levering force that is counter to the string tension. That might actually tend to balance the forces acting on the block as long as your bass is not real heavy and the pin is relatively short. As long as the endpin does not come too close to the table when retracted, I think you will be OK. Just don't make the angle too severe. You may want to fill in the old hole also because there would be a chance that the wood would be too thin between the old vertical hole and the new angled one and the pin could split through more easily than the 1/500 (actually 2/500) statistic for blocks with only one hole through them. Or, if you do go inside the bass, you could put in a new block, wood strength of your own choosing. I think Erik is correct that the metal flange is overkill. You can gain plenty of strength with wood if need be, without using metal.

[Savino]

I have no idea what all this fuss is about. I have a Laborie endpin on my la scala. I love it. The hole i had drilled is nowhere near my other endpin. Buy it from George Vance. Its 75 beans. It comes with precise instructions for luthiers. You wouldn't use it to sit. That defeats it's purpose. In no way do I feel that it jeopardizes your end block unless its made from balsa wood

[myrick]

sliver, thanks for the input.

of course you are correct - how the stresses bear on the block depends on the angle of the hole through the block relative to the angle of the force vector from the bass's weight bearing down to the floor. Without wishing to ignite a debate about posture and supporting the bass, let me explain how I hold the bass. Over the years I have tried everything from the Karr-style (bass quite vertical, even leaning slightly forward so some of the bass's weight is driven into the fingers of the left had) to the Rabbath approach (with the bass low and more horizontal, cello-llike) and all permutations in between, both sitting and standing.

I have ended up preferring to stand, with the bass relatively horizontal, leaning back onto me, supported by my chest (back upper bout) and left shoulder/neck (crook of the neck). To accomodate such a stance, after much experimentation, I have the point at which my DIY S-shaped, non-retractable endpin meets the floor at 1) forward/rear, approximately on the same plane as the back plate of the bass, to brings the support point at the floor closer to underneath the bass's center of gravity, thus reducing the weight on my body somewhat; 2) left/right, a few inches to my left from the bass's centerline (toward treble side), to encourage the bass to torque clockwise into my body for stability, treble to bass; and 3), up/down about six inches below the bottom plane of the bass.

Eyeballing, I would estimate this means with a straight pin if the hole were still through center of the block it would need to be at an angle of roughly 35 degrees from the orginal "vertical". I could reduce the angle and thus the leverage forces by moving the hole closer to the back and side of the block, but of course I would have less wood on one side of the hole (unless I make a wider block or put it off center - too wierd).

To reiterate, the main reason I want to make a new hole in the first place is to replace my DIY S-shaped pin (which works OK) with something that'll retract for transport. I also hope to switch to a wooden pin in hopes that Traeger is right about sound - and I'm quite sure he must be.

I figure its a fair bet that the Laborie pin will work sonically more or less like wood, so I think I'll give it a try.

Sav - its encouraging to hear you say how simple it is. You just drilll the hole and stick it in, eh? Sorry to pester with so many questions, but I'd really like to understand more how this worked for you. how much angle do you reckon you have off the straight vertical ? No sign of stress from this angle? how far away from the orginal endpin hole is the new one, leaving about how much wood surrounding it? Did you plug the old hole? Does the Laborie thing retract like a normal pin? Where is the tailpiece wire afixed? Did you notice any sound difference after the switch?

thanks, all

[Savino]

Originally Posted by myrick

Sav - its encouraging to hear you say how simple it is. You just drilll the hole and stick it in, eh? Sorry to pester with so many questions, but I'd really like to understand more how this worked for you. how much angle do you reckon you have off the straight vertical ? No sign of stress from this angle? how far away from the orginal endpin hole is the new one, leaving about how much wood surrounding it? Did you plug the old hole? Does the Laborie thing retract like a normal pin? Where is the tailpiece wire afixed? Did you notice any sound difference after the switch?

The Laborie pin is a very simple thing. It's a carbon fiber shaft with a tapered collar at one end and a rubber ball at the other. Your existing endpin remains untouched. The hole is made with an endpin reamer about 3/4 of an inch from the back at a 44 degree angle. Your luthier should bore the hole until the pin fits snugly. Then you cut the shaft of the pin until your nut is at eye level. (Insert witty remarks here) If the endpin was smaller in diameter I'd be worried but it is actually quite thick, reducing the stress on your endblock. I feel that the increased mass of the endpin allows greater vibrations to pass between the bass and the floor. It doesn't retract at all. You just pop it in and out like an old school wooden endpin. Your sound gets projected up and out. Some times in my studio, when i bow a really fat note all the **** hanging on my walls (banjo, guitar, saz, snare drum) sypethetically ring. Thats a great day for me.
Hope I got it all.
buona fortuna
sav

[myrick]

thanks savino

for anyone still following this thread, here is a bit from a David Gage article on endpins:
The Rabbath-Style Endpin
Another non-adjustable endpin is the “angled” type, conceived and used by French bassist Fran¸ois Rabbath. France’s Christian Laborie makes a carbon-fiber version of this endpin style. It is installed at about a 45-degree angle so that the bass slants back toward the player. Great care must be taken to examine the endpin block’s location and health before installation. The hole for this endpin should not be drilled too close to the block’s outside edge, and there should be no cracks or weaknesses in the block—especially since this is usually the second hole in the block.