Cheap Chinese headless tuners. How do I make them work right?

[smart51]

I've nearly finished building my first bass and today I put the strings on (yay!). I'm having a bit of trouble with my tuners though.

For a 5 string headless bass, there seemed to be 3 choices. A Hipshot bridge with tuners at £300 (about the cost of a whole Squier 5 string), individual ABM tuners at £250 or cheap Chinese ones off eBay for £50. I bought the cheap ones.

There is a base plate that screws to the body, then the tuner bolts to the base with a single small bolt. This allows the bridge to be moved for adjustment. The problem is that it slips, even when the tiny bolt is done up tighter than seems a good idea. You can see in the photo that the G string has slipped.

The grub screw that holds the string is even smaller and I don't think it would survive many tightenings. Turning the tuners takes a lot of finger force too, though the ends are slotted, so I might make a winder for them.

The threads were covered in swarf and the bearings not greased, so I'm not very impressed, though that was easy enough to fix. I had to drill out one of the tuners to take the low B string too. They came drilled out to 3.2mm, enough for a 125 gauge string. With a bit of work, I think they can be made to be servicable.

Anyway, do you have any ideas how I get them to stay put when I tighten them up?

 

[bholder]

Buy better tuners? Sorry.

 

[buldog5151bass]

Can't make chicken liver out of chicken poop. The only thing I can add is to look in your classified for a used headless bass to cannibalize for better tuners.

 

[wraub]

...those look more like guitar tuners imo.

 

[charlie monroe]

You haven't shown us an exploded view, but my first instinct would be to use a threaded insert to receive the machine screw that holds the bridge in place on the mounting plate.

Is that plate threaded?

Is there enough clearance under that plate for the screw you are using? ie is the body causing the screw to bind?

I'd love to see one unit completely disassembled. Pics?

 

[bobdabilder]

Yes, disassemble one and take detailed photos so we can help.

 

[smart51]

You haven't shown us an exploded view, but my first instinct would be to use a threaded insert to receive the machine screw that holds the bridge in place on the mounting plate.

Is that plate threaded?

Is there enough clearance under that plate for the screw you are using? ie is the body causing the screw to bind?

I'd love to see one unit completely disassembled. Pics?

Good suggestion. Yes the plate is threaded, and with the screw tighened, there is about 1mm spare before the end of the bolt goes through the plate.

This eBay listing has photos of the part that show how it works.

Metal Single Headless Round Bar Bass Bridge Kit Music Instrument Accessory Well | eBay

The body of the tuner has a long hole milled in it, with a slot in the bottom. The screw goes in the long hole and through the slot into the base. The slot allows the body of the tuner to be moved along its length so that the distance from the nut to the bridge can be adjusted.

The bridge is a round brass insert. There are two tiny grub screws to adjust the height, plus a locking grub screw in the end of the body.

The tuner part is a hollow screw, with a grub screw to clamp the string. Turning the tuner handle pulls this screw towards the end of the tuner, pulling the string with it. The opposing force is put on the body of the tuner, which is clamped to the base with the small bolt in the milled recess. The tension in the string is overcoming the clamping force of the small bolt, so the body is sliding towards the pickup rather than the string being pulled tight.

Here's another photo, with a spare tuner to show what's going on

 

[smart51]

...those look more like guitar tuners imo.

I think so too now I've seen them, though the bore is quite big for a guitar string. There are lots of them on eBay from different sellers. All of them are the same. Most of them are sold with 5 string in the title. It doesn't guarantee the seller knows what that means.

 

[bobdabilder]

Is the body only attached to the grey/aluminum colored riser with the small single screw? Can you detach that and take a pic from the side?

 

[Reedt2000]

Put some loctite on the screws that go into the plate. Try to lube the tuning mech with something light that doesn't evaporate off, lithium grease maybe. I think that's the best you'll get them. You can't polish...



Edit: almost forgot, pics of the whole bass! (Or link to a build or NBD thread).

 

[bobdabilder]

Drill and tap another screw from body into that block so two screws are holding.

 

[Dirk Diggler]

Yeah those knobs are really small diameter compared to the ABM or Hipshots, that would explain the hardness of tuning.
The Hipshots are almost identical to the ABM.

I've been tempted by these, and now will most likely not grab some to try.
Maybe they would be workable in guitar builds. It looks like those are clones of Strandberg ones.

Dirk

 

[kodiakblair]

The 5mm machine screw is used to fix the saddle and set intonation or at least that's how I viewed it.

 

[arbiterusa]

As far as tuning them goes, check out the Nova Headless threads (there are only a couple) you want the one where some awesome dude explains thrust washers. That's going to make them work a LOT better.

 

[kodiakblair]

you want the one where some awesome dude explains thrust washers.

The cheap Chinese headless tuners I bought came with thrust washers,none of these tuner types work without them.

 

[Reedt2000]

So, the whole saddle assembly moves to adjust intonation? I wonder if you could line the surface of the plate in the body, and the underside of the saddle/tuner assembly with material that would create friction. Rubber? Cork? Gasket material? Strips of super-light sandpaper? Something to help resist string tension. Maybe even a tiny washer under the head to spread out its grip a bit (with split washer if it will fit).

 

[Roland GR 88]

Good luck but........I would just buy a set that actually work and are designed to last. Compare yours with the Hipshots and you'll see where the extra $$$'s go and why.
Plus, as already mentioned, those are guitar tuners. That's not a spare, it's the 6th one.

 

[kodiakblair]

Maybe even a tiny washer under the head to spread out its grip a bit..

That sounds the best solution.

 

[Clark Dark]

I've never bought anything from ABM that wasn't built to last. Quality stuff.

 

[kodiakblair]

Maybe this will help.