Japanese bass 1960's?

[AntFoster]

Hi,
I'm new to basschat. My 12 year old son plays bass and recently bought a beat up bass off ebay as a project. It's made in Japan and looking at similar basses on google images I think it might be 1960's. There's a faded shape where the maker's badge was (see photo). There's two main things that need fixing. Firstly it has no bridge! Can't figure out what it would have looked like to see if we could adapt a different bridge or otherwise I have a friend who works in metal and could praps make a bridge. I've tried to show in the photo's how high the strings will be when they hit the bridge which seems very high to me. The other thing is the wiring. I've got a diagram of a two pickup set up for a Jazz bass, but the pickups on my son's bass have different amounts of wires coming from them! Does anyone know what's going on? There's an inner wire and an outer wire sheath coming from one pickup and two inner wires plus an outer wire sheath coming from the other. I don't know much about pickups but is this normal?!

Any help/ideas much appreciated,
Anthony

Edited October 20, 2014 by AntFoster

[PlungerModerno]

Those pickups are almost certainly humbuckers - gudging by the 4 wires I can see coming out of one. I could be mistaken as the pic is not completely clear.

I think it does have a bridge - just no saddles.

yer missing something like this:

[Andyjr1515]

I think you've got yourself quite a challenge there!

Because the pickups are mounted on the surface of the top, rather than the now almost universal approach of sinking into routed chambers in the top, the bridge is going to be much higher than most commercially available ones. The simplest way would be to mount a standard modern bridge on a block of wood. Not elegant but, if you can still use the existing string retainers, you wouldn't at this stage even have to bolt it down. Also have a look at the bridge that hofner use on their violin basses. They are also high and free floating. When I have a moment I'll send you a link.

But before you spend a lot of time and effort, find someone who can confirm the pickups are still working...

[HowieBass]

You also need to check that the neck is straight and that the truss rod adjustment still works (moves); there's no point in getting the instrument all screwed back together with new parts for the bridge to find that you can't adjust the neck to set the right amount of relief. This obviously assumes that the pickups work as do the control pots.

[AntFoster]

Thanks for your replies. As it's more a way for my son and me to learn about how basses work (or don't!) I've followed the principle of throwing good money after bad by ordering a bridge similar to PlungerModerno's pic except its the complete unit. We'll try to adapt this by fitting the saddles into the current bridge or could replace that and raise the new unit higher. Then we'll move onto the pickups and cry tears of pain if they don't work. I'll try and put a better picture on cus still don't understand why one pickup has two wires and the other has three wires. The one with three wires looks as if it's been opened up at some point cus there's electrical tape on the back of it (not a good sign). If we can get strings on and it makes a noise when plugged in that will be a happy moment even if it's never really playable.

[HowieBass]

There's a chance the pickup with three wires has a coil tap option where you can achieve both a single coil and humbucker arrangement in one pickup body. First thing I'd do is measure the pickup DC resistance with a multimeter - you'll have an idea then how the three wire unit is connected up. Without knowing much about those pickups you probably will be looking for maybe a 10 to 20 K ohm resistance and I guess the pots might therefore be something like 500 K? Hopefully other Basschatters with better knowledge on the parts used on basses of this era will be able to tell you more.

[PlungerModerno]

[quote name='AntFoster' timestamp='1413803152' post='2581995']
Thanks for your replies. As it's more a way for my son and me to learn about how basses work (or don't!) I've followed the principle of throwing good money after bad by ordering a bridge similar to PlungerModerno's pic except its the complete unit. We'll try to adapt this by fitting the saddles into the current bridge or could replace that and raise the new unit higher. Then we'll move onto the pickups and cry tears of pain if they don't work. I'll try and put a better picture on cus still don't understand why one pickup has two wires and the other has three wires. The one with three wires looks as if it's been opened up at some point cus there's electrical tape on the back of it (not a good sign). If we can get strings on and it makes a noise when plugged in that will be a happy moment even if it's never really playable.
[/quote]

OK dokie - glad to be helpful (If I was - I could be wrong!). Best of luck with the project anyway - if you make any progress please keep us updated (pics please!).

Judging from the first and last pic (full front shot showing bridge cover; closeup of bridge plate). I think it may be worth checking neck function and alignment, as suggested already. even with only two (of 6?) screws holding the bridge plate(I assume) down - you can still take a thread or string under hand tension and see how the neck angle is set. Holding it from bridge to nut should give you an idea. Another vital test is truss rod function. I'd take the neck off (I'm assuming it's a bolt on) and carefully match a wrench to the truss rod nut in the heel - try unscrewing it - it should move without excessive force. If you can get it off a small spot of grease (or oil) will help future adjustments.

+1 to checking the pickups for function.

As I understand it that style of bridge plate works by sitting the strings in the four notches (held in place by string tension & the ball ends) - and resting on the saddles whose intonation screws (with springs) feed through the 4 holes below the notches. I may be mistaken.

[iiipopes]

The bridge may have saddles, or it could be a bar-type bridge similar to a guitar bridge. It looks like it has been replaced once a long time ago. Look at the old screw holes under the current bridge plate. You should be able to find one. The pickups are NOT humbuckers. I've worked on many guitars and basses that have these pickups. They have only one coil under the cover. Look at the back: only one set of screw holes is filled. That's how you tell. The spare wire is a cover ground.

It is great that your son wants to know how it works. I still have my first electric guitar my parents purchased for me in 1975. Over the years, I have rewired it in all ways, changed the bridge and tail piece, added a 22nd fret, changed the bar for string trees at the headstock, had the first few frets replaced when they wore out, and next week it gets new pickups. I still play it out occasionally.

Here's probably what it looked similar to new:

Edited October 20, 2014 by iiipopes

[AntFoster]

Thanks again for your replies. Sure you're right iiipopes about there being a [font=helvetica, arial, sans-serif][color=#282828]bar-type bridge originally. This one must have been on for some time cus the paints faded around it. Feel more confident we can get it working now. Thanks for the advice about the cover ground. It's a long way from it's original condition looking at your photo; must have had an exciting life![/color][/font]

Edited October 20, 2014 by AntFoster