JM-1 Help

[coriem76]

I'm a newbie building my first jm-1.
I'm struggling with an incorrect wiring diagram, however, don't believe it should be that difficult.
I have four wires ( Green, red, Orange and yellow ).I have the black but know what thats for.
The four wires I believe, tell me if I'm wrong, need to be soldered to the 5 way switch and I'm not sure what goes where.

Hoping someone can help me a trip to the music shop!

Cheers

[WeirdBits]

This thread about JM-1 wiring (http://pitbullguitars.com/?page_id=42&mingleforumaction=viewtopic&t=4.1) may help. Hopefully, your layout looks something like this:

http://pitbullguitars.com/wp-content/uploads/2013/08/1spkd-jm.jpg

It looks like you should have a black ground wire that connects to the tremolo/bridge to the back of a tone pot. Then, you should need to connect an output wire from the switch to the volume pot, and then separate wires from the switch to each tone pot. You should also connect a ground wire from the pickup grounds (negatives) at the switch (ground lug) to the common ground point on the back of the vol/tone pot. Although this diagram has a single coil bridge pickup and your switch position is different, the basic wiring layout should match what you need:

http://pitbullguitars.com/wp-content/uploads/2013/08/836n5-StratImport2.jpg


Does that help?

[coriem76]

Massive Help... Thanks

[lawry]

Timing is everything. I am almost at the stage of wiring up my JM and now I don't need to go hunting. Thanks man!

[cslessar]

Yeah really big help.

I, like Coriem am also a newbie building my first JM-1. That wiring diagram was a big help. I was wondering if anyone could assist with an issue I have been having with attaching the bridge. The two bolt holes that came already drilled into the body seem too close to the hole where the bridge is supposed to be input. I have inserted the bolts that the bridge sits up against, however, when it comes to putting in bridge piece, it won't fit…

So I guess my questions are as follows:
- How likely is it that the bolt holes and the bridge hole have been incorrectly drilled by the factory that makes these guitar parts?
- Should the bridge fit in easily against the bolts, and in fact have some slack?
- Also, do the bolts need to be hammered in flush against the body of the guitar?

Any help would be great.

Cheers

[lawry]

Hi Charles.
I had a few little 'imperfections' with the bridge arrangement on my JM build too. The biggest one being that the post holes were not deep enough to allow the post to be flush when hammered in. So check that. As for your issues, I can't quite visualise what you're saying. Any chance of posting a picture?
Cheers

[dingobass]

OK,
Firstly, dont hammer the bushings in! You are better to press them in with a large g clamp or a drill press..
If you dont have access to either then very gently tap them in using a block of timber to protect the bushings.

Next up, screw the bolts in about a quarter of the way, so they still has a little bit of wobble. the bridge should then slip on.

Then with a large screw driver you should be able to lower the bridge to the correct height when you do your set up :)

[cslessar]

Hey thanks for the quick reply guys,

Unfortunately I am at work right now so I can't upload any pictures, though I will do that tonight Lawry.

Hey Dingobass - ok so I won't hammer them in, but they currently won't sit flush with the guitar body so perhaps I need to drill a little bit more so they can easily get deep enough...? Also, I have tried what you suggested about only screwing the bolts in about a quarter of the way, however, the bridge will not slip in. I have also tried putting the bridge in one bolt at a time, however in this situation I encounter two problems:
1.) When screwing in the second bolt, as the bridge is so tight against the bolts, instead of pulling the bridge down onto the guitar, the bushing lifts out of the guitar.
2.) When I did manage to get the bridge as far down as possible, it is so tight up against the bolts that if I were to attach the tremolo bar, there is no way that the bridge would lift up and down...

What I was thinking of doing is filing down the hole (where the bridge goes) toward the bottom of the guitar body so the bridge can move about more freely once in the hole.

Will upload some photos tonight, though would really appreciate some more help.

[wokkaboy]

should be able to work out a solution Charles once we see some photos.
Take some above and below photos so its clear

[cslessar]

\\\\uds\\5\\cslessar\\Desktop\\guitar 1.jpg

Alright so I've measured it and it is 7mm from the bridge hole to the edge of the bolt holes

[cslessar]

Alright, I know that this doesn't look good but I have no clue how to add a photo. Have tried everything other than writing code, because I can't.

Sorry fellas.

[WeirdBits]

Click the "Reply" button (part of the blue 'Reply | Subscribe | RSS feed' lower and upper right of the page), then there should be three 'Choose File' buttons to upload images below the text box.

[lawry]

/<\\/p>[]<\\/p>/Quote from cslessar on August 12, 2014, 18:45
Alright, I know that this doesn't look good but I have no clue how to add a photo. Have tried everything other than writing code, because I can't.

Sorry fellas.

Don't feel bad about that, mate. You're by no means alone if you're new to the forum. Weirdy has all you need above.

[cslessar]

Thanks for the support lads, I got there in the end.

So here are three images of the guitar in progress:

The first is a body shot. I have measured the distance between the hole where the bridge goes to the edge of the bolts where the bridge sits up against and it is 7mm (give or take half a mm)

The second shot is a profile of the bridge in place. As you can see, it will not sit flush against the guitar and bolts.

The third shot is a kind of a diagonal shot of the bridge looking down the body of the guitar where, once again, you can see that the bridge does not sit flush against the guitar.
http://www.pitbullguitars.com/wp-content/uploads/2014/08/821h9-IMG_2377.jpg
http://www.pitbullguitars.com/wp-content/uploads/2014/08/srber-IMG_2381.jpg
http://www.pitbullguitars.com/wp-content/uploads/2014/08/37hvj-IMG_2382.jpg

[cslessar]

Also, you can see from the third image above that the bushel also does not sit flush with the guitar.

[dingobass]

ok.
first, the bush can be fixed by drilling the hole slightly deeper.
or you may be able to file a bit off the bottom of it, there should be plenty of meat there to allow the stud to seat properly.
Secondly, the bridge actually sits in the vee groove part above the thread (you probs know this so tell me to shut up) :)

[dingobass]

BTW, I really like your minimalist approach to the finish... Very slick :)

[cslessar]

Thanks mate, yeah I was aware that the bridge sits in the vee groove (but I couldn't upload a photo so fair call). The only trouble is when I put the bridge into that groove and screw the bolts down into the bushels, the bridge is really tight against the vee groove such that I don't think I am going to be able to utilise the tremolo once the build is complete.

Should it be that tight?

[dingobass]

No... It should not be that tight.
A work around would be to grab a half round jewelers file and adjust the bridge grooves so it fits properly.
Prolly only needs a smidge removed to work :)

[dingobass]

I should clarify that it needs to be firm, not loose and wobbly!

[wokkaboy]

I agree with DB, looks like you have to file away some of the rear of the bridge cavity so the bridge can pivot while sitting on the V groove when they are screwed down flush with the body

[cslessar]

Yeah riiight...

That's what I thought. Not an issue, I'll get on it.

My only concern is that I have done a few measurements from the saddle to the 12th fret and from the 12th fret to the bridge hole and they aren't the same (the second measurement is about 2cm longer).

So I guess my last question (hopefully) is - how important is it that the distance from 12th to saddle is the same as the distance from 12th to bridge?

[wokkaboy]

I've not built a JM-1 so would be better if a forumite who has built one checked their measurements. Looking at the above photo the bridge pivot holes don't seem to line up with the cavity. Can you please post a photo of the bridge installed on the pivots from above ?
2cm difference seems too much 12th fret to saddle distance. The bridge should be perpendicular to the centreline of the neck and you move the bass string saddles more rearward than the treble strings.
I'll wait for a photo, maybe if you can please place the ruler on the neck so zero is on the 12th fret - cheers. Also if you can post the nut to 12th fret distance would be great.