Tuning machine rattling driving me nuts

PB+J · #1 01-26-2010, 10:02 AM

On my Shen bass, a 7/8 willow flatback, the machines rattle on certain notes. Drives me nuts. I'll take each machine apart and lube and tighten everything, but while I'm thinking about it--tuning machines--big deal or not? They hold tune just fine, they turn easily enough. Is there a big difference worth the big price for new machines? Those Irving Sloan Machine look really nice, but so does $599 in cash look nice, in my bank account

Greg Clinkingbeard · #2 01-26-2010, 10:59 AM

The Sloans are beautiful but I have no experience with them. However, I have had two basses with the KC Strings machines and like them very much. They are well made and machined to high tolerances which makes them do their job and not rattle.

http://kcstrings.com/bass-machines.html

My preference is for the smooth variety but YMMV.

arnoldschnitzer · #3 01-26-2010, 04:23 PM

If you slightly loosen the screw that holds the large gear in place, the machine will free up. These get bound-up when that screw is tight, and then the handle flops around and rattles. This info was given to me directly from the Shen guys, and it worked for me on several occasions.

PB+J · #4 01-26-2010, 04:57 PM

Thank you Arnold--that's a great tip. My impulse was to do the opposite.

But meanwhile, while I was snugging down the plates, the heads cracked on three of the little screws. Now I have to figure out how to get them out! I might be able to grab the part that sticks out from the wood when the plate is removed.

Sigh...

moles · #5 01-26-2010, 08:36 PM

They make those little screw remover gadgets now - you stick one on your drill and counter-bore into the broken head while unscrewing. Don't know how small they come for the little screws though.

mje · #6 01-26-2010, 08:54 PM

If you can't find a small enough Easyout, you may be able to find a left-handed thread twist drill. Irwin (among others) makes them.

PB+J · #7 01-27-2010, 05:55 AM

I'm off to the biggest local hardware store today to see what they have in the way of screw extractors, and then tomorrow I'll have time and space to try to back the screws out.

It was odd how easily they broke, and they broke in an unusual way. Usually when I break screws I'm really twisting, and the head snaps off the shaft. But in these the heads partially cracked. Never seen if before. I'm going to replace them all with stainless steel screws if I can find them

Jake deVilliers · #8 01-27-2010, 11:42 AM

The head split because modern screws are cast - not the best recipe for strength. Stainless steel is pretty soft - you'd be better off with steel or good brass.

robobass · #9 01-27-2010, 12:47 PM

Quote:

Originally Posted by Jake deVilliers

The head split because modern screws are cast - not the best recipe for strength. Stainless steel is pretty soft - you'd be better off with steel or good brass.

DISAGREE!!!! I'll post later about material strengths when I gather some #s, but SS screws are the best. I even plate 18-8 SS screws and send them with my product so that luthiers won't be tempted to use brass screws - which break easily.

When you break tiny screws like this, you're pretty much "screwed", pardon the pun. There are no extracters this small, and they wouldn't work anyway if there were. If the broken screws were brass, your best bet is to drill out a large bore and plug the hole. Note: You cannot do this with a hand drill. The scroll must be totally secured in a drill press or you will make an even bigger mess.If the screws were iron or steel, you're f#*§$d, and have to dig out the wood around the shaft with a Dremel until you can get purchase and extract the screw, and then you really need to bore and plug!

PB+J · #10 01-27-2010, 01:07 PM

Thanks all for the replies.

The screws were brass-looking, but the phillips slots in the heads are odd--they are off-center and what broke was part of the head where the phillips slots were. I have one screw in my pockets and it's got a crack in the head. I've never seen this before.

I'm skeptical that brass is harder than stainless--but either way, i can't tell if the replacement screws are alloyed with good brass of weak brass just by looking.

Bought one of those tube bits that drills around the screw, and a hardwood dowel for plugging, but I doubt I'll be able to use it. If I'm lucky, I'll be able to grab enough of the shaft with pliers and back the busted screws out. There's no way I can get the scroll on my drill press, no way in hell. I could probably drill the brass out.

Shen used really bad screws--i really did not tighten these hard at all

vejesse · #11 01-27-2010, 01:10 PM

Don't forget that you can make a little plug cutter by taking a piece og brass or steel tube that's just larger than the screw shank and then file some little teeth in one end. Chuck it in an electric drill and you can remove the screw and make a nominally sized hole that's ready for a dowel.

vejesse · #12 01-27-2010, 01:11 PM

just beat me to it.

robobass · #13 01-28-2010, 05:55 AM

Quote:

Originally Posted by PB+J

Thanks all for the replies.

The screws were brass-looking, but the phillips slots in the heads are odd--they are off-center and what broke was part of the head where the phillips slots were. I have one screw in my pockets and it's got a crack in the head. I've never seen this before.

I'm skeptical that brass is harder than stainless--but either way, i can't tell if the replacement screws are alloyed with good brass of weak brass just by looking.

Bought one of those tube bits that drills around the screw, and a hardwood dowel for plugging, but I doubt I'll be able to use it. If I'm lucky, I'll be able to grab enough of the shaft with pliers and back the busted screws out. There's no way I can get the scroll on my drill press, no way in hell. I could probably drill the brass out.

Shen used really bad screws--i really did not tighten these hard at all

It's unfortunate, but there seems to be no limit to how crappy low-end screws and fasteners can get, and many manufacturers resort to using them to cut a few pennies off their bottom line, even if the rest of the product is well made.

As to my statement about SS screws, I can't seem to find a good direct comparison online, but in general, 18-8 or 316 SS fasteners have about double the yield and tensile strength of brass. And, don't even bother trying to find decent stuff at Home Depot. You need to go to a fastener specialist online.

As to your predicament, isn't it time to consult a bass luthier? You should have several good ones within driving distance. Try Thomas Andres Double Bass Makers. I really don't want to sound condescending - it sounds like you have some basic tool skills, and you might manage to dig yourself out of this mess without help. But, pro bass luthiers deal with this stuff regularly, and can certainly solve the problem much more quickly and neatly than you can. Again, absolutely no offense intended.

PB+J · #14 01-28-2010, 06:13 AM

No offense taken, and thank you. I've got a lot of tools and some reasonable woodworking skills, enough to have built a couple solid body instruments from scratch a few years back. If I can't back the screws out I'll probably take it to Thomas Andres Wolf--he's done some work for me before and I need to have a crack repaired anyway.

The thing that puzzled me was the rattle, and Arnold explained a good way to fix that

PB+J · #15 01-28-2010, 08:36 AM

Success! I was able to back the screws out with patient application of a good pair of lineman's pliers. Replaced them with a better set of stainless screws, tightened it up, backed of the screws as per Arnold's suggesition and....

It still rattles. On the "A" and the "Bb" on the G string. %$^@!!

Ah well. Perhaps a resonant rattle is part of the musical sound of the universe...

jmpiwonka · #16 01-28-2010, 10:34 AM

i have a shen willow bass with the brass tuners.
the screw that goes through the middle of the actual gear, it rattles. i usually just tighten it with my thumb nail...should get a screwdriver and tighten maybe another 1/16th of a turn...
could maybe try a bit of the light loctite on there so that the screw will stay where you want it.
you want that screw just snug. too tight and it will make the gear hard to turn.
same with very small screws that clamp the shaft of the knob. want them just snug.

PB+J · #17 01-28-2010, 10:40 AM

Makes sense, and that's how they are--snug. If I loosen them, the rattling gets worse. If I tighten them, it gets better, but then they get really hard to turn.

I'm thinking of putting some of that teflon pipe tape under the gears, so there's less room for rattling

**Damon Rondeau** · #18 01-28-2010, 11:41 AM

Two comments, who knows if either of them apply to you:

1) Sometimes it's the ears of the tuner that are rattling. They get loose in the little bridle joint they sit in on the end of the post. I squeeze 'em shut with pliers.

2) Putting screws into hardwood is different from softwood. There's very little room for error. The type of hole you make to accept the screw matters tremendously. If it's too shallow and the screw bottoms out, chances are very good you'll torque the screw apart if you try to man it in there. Same thing can happen if the hole's too small in diameter. Know thy screw, and know the hole thy screw wants.

PB+J · #19 01-28-2010, 12:04 PM

Yes I know, it's true about hardwood and brass. But I feel [i]extremely[i] confident in saying these were defective screws. The phillips slots were cut off center and they cracked at the slots where the slots were off center.

But I did check, it's not the "ear" that's rattling. I took all the tuners apart and checked. It's the big gear, rattling against the plate or the screw. I need my wife to hold the tuner while I whack away on the G string between A and Bb. She's gonna love that.

Probably the solution would be to shim the actual peg shaft where it enters the big gear, so it's a tight fit.

PB+J · #20 01-28-2010, 12:09 PM

Yes I know, it's true about hardwood and brass. But I feel [i]extremely[i] confident in saying these were defective screws. The phillips slots were cut off center and they cracked at the slots where the slots were off center.

But I did check, it's not the "ear" that's rattling. I took all the tuners apart and checked. It's the big gear, rattling against the plate or the screw. I need my wife to hold the tuner while I whack away on the G string between A and Bb. She's gonna love that.

Probably the solution would be to shim the actual peg shaft where it enters the big gear, so it's a tight fit.

I'm thinking I ought to review this Shen bass. It's been five years since I bought it. There's a lot to like but little things like this that are a bit annoying