8 String Bass Bridges with 8 Saddles

[Low End Lover]

If these are aluminum, chances are they're going to bind big time after a fairly short period of time.

Since these are, can someone explain what this means and the issue it will cause?

Thanks,

LEL (Jason)

[aceonbass]

My 5-string aluminum bridges that I use for my 4-2-5 conversions are machined out of aluminum also. I haven't had or heard of any problems yet, but mine weren't chrome plated either. Maybe this makes the tolerances to tight or something?

[teeder]

Thanks to Dane and John for the input.

The bridges will be flash chromed, so the build up will be at a minimum.

John, please elaborate as to what binding issues we may run into.

Thanks!

[Low End Lover]

Paging Mr. Hall... Help us out please!

[Ric N. Backer]

You might want to consider soliciting John Hall's input, regrading the technical stuff, off-line.

[aceonbass]

Paging Mr. Hall... Help us out please!

He already helped us out by saying these were okay to make and advising that brass was a better material. Not that I doubt anything he would say, but once you've intonated your 8-string with these aluminum bridges, I don't think you'll be doing it again any time soon, so the binding issue shouldn't surface in normal use. Like I said earlier, my CNC'd aluminum 5-string RIC-style bass bridges are just fine.

[cjj]

When two metals, especially soft ones like aluminum, and often when they are the same metal, are in contact under pressure, you can get "galling". This is a plastic deformation and adhesion between the surfaces. This can happen with just pressure, but is worse with movement/friction.

The chrome plating will help, but if it's thin, may not be enough...

[rickaddict]

When two metals, especially soft ones like aluminum, and often when they are the same metal, are in contact under pressure, you can get "galling". This is a plastic deformation and adhesion between the surfaces. This can happen with just pressure, but is worse with movement/friction.

The chrome plating will help, but if it's thin, may not be enough...

I've heard of something similar happening with high-end lightweight bicycle parts...

Would it help if a thin layer of grease were applied to the mating surfaces?

[cassius987]

Josh,

Sorry man, the number of bridges is 8. One was a prototype that has some machining issue.

That's okay. I have too many other irons in the fire anyways.

[weemac]

When two metals, especially soft ones like aluminum, and often when they are the same metal, are in contact under pressure, you can get "galling". This is a plastic deformation and adhesion between the surfaces. This can happen with just pressure, but is worse with movement/friction.

The chrome plating will help, but if it's thin, may not be enough...

I've heard of something similar happening with high-end lightweight bicycle parts...

Would it help if a thin layer of grease were applied to the mating surfaces?

I remember once making a model steam engine and I used brass for the cylinder and aluminium for the piston. When I test fitted it slid in and bound. It was like it was welded in there. I mangled both parts trying to seperate them.
I think I used brass and bronze for my next effort and that worked fine (until the boiler blew up)

Eden.

[aceonbass]

Aluminum and brass have two different rates of expansion. Kevin's bridge and saddles are made of the same material. I would think that unless you're cycling the saddles back and for a couple hours at a time, there would be no issues. As I've said, I use zinc RIC bass saddles on aluminum 5-string bridges with NO problem at all.

[weemac]

Well the original cast aluminium bridge had saddles to match and the chrome did a good job of stopping the saddles binding in most cases.

Kevin are the bridges left as a solid bar or are they hollowed like the Rickenbacker ones?
On my 4008 the bridge has sagged a bit in the middle and is held from deforming further by the grub screws locking into the holes in the tailpiece (previous owner had fairly heavy strings on it). A slightly more solid 8 string bridge is not a bad idea.

Eden.

[teeder]

Hollowed, but the side walls are thicker.

[henry5]

Kevin, if you ever do anymore I may be interested.

[weemac]

Hollowed, but the side walls are thicker.

Good stuff! It will put the strength up and keep the tone nice and even.....

Eden.