Harley Benton MB-4 intensive overhaul

[j-stylez]

Hi! I just owned a shortscale Jaguar bass for a while, until I understood I need a real bass with 34" scale as well, for some things to sound differently.

I dig the sting ray sound. I like the simplicity of just one pickup, 2 Band eq, pure but versatile. I like firm lows, scooped mids and some zing. And a lot of other stuff too.

Most of all, I love to build stuff. So I got myself a Harley Benton MB-4 as the basis for an intensive overhaul.

Built the low current consumption 2 Band EQ to original specs. Rewound the Roswell pickup to ~4200 winds, 3.5k per coil. I kept the ceramic magnets, these are of course not Vintage correct. But I think I like them, and I like some bite in my tonal options. So I think I'm good there.

I gotta say, this is killer. I Built the preamp first, tested it with the overwound roswell. Way too dull. Rewinding the pickup was a pain only because taking that black plastic off the back of these roswell pickups is a nightmare. Huge nightmare. Had to drill many holes, plastic bits chipping off and flying everywhere. Had a crack in the cover but was able to fix it. Reused everything except the copper wire. Coils are wax potted. Lowered the poles to be flush with the cover.

Finally, still working on the neck. I like slim necks. The neck felt like a club out of the box. Now it's 37mm at the nut, still working on the profile.

Headstock converted to 3L1R. Reused the original tuner, reversed one tuner peg. Nut will be bone, but only making that when the Profile is done.

Headstock will be reshaped, neck then lacquered with some satin nitro.

I'm loving the sound and feel already! Here are some pics.

 

[j-stylez]

I used a chisel for the battery compartment, no routing on this project. Since it's the low current preamp, a battery under the pickguard is fine.

 

[j-stylez]

The bridge is something I'm not sure about yet. I dont like the big plate, but the original style seems impossible to buy aftermarket. I might just reshape the contour of that big plate and build myself some brass saddles for it, just because I like brass saddles.

I'm still undecided about the final headstock design, probably a slight diagonal concave curve at the top end where the rough cut is still visible.

 

[j-stylez]

I made a bone nut for the narrowed profile. My first bass nut after many guitars... I found it more difficult to do a bass nut, because it is harder to move the slots while working to the final depth. The E-string grove is too wide at the top for that reason. Might have to redo it, but it holds. I'll Keep it for now and see if any problems arise. Still have to glue it down.

 

[Matt Liebenau]

I made a bone nut for the narrowed profile. My first bass nut after many guitars... I found it more difficult to do a bass nut, because it is harder to move the slots while working to the final depth. The E-string grove is too wide at the top for that reason. Might have to redo it, but it holds. I'll Keep it for now and see if any problems arise. Still have to glue it down. View attachment 5144067

As long as where the string actually sits is good. In fact, you could take the top of that nut down until it’s holding only half or slightly more of the string diameter. That’s what I typically shoot for from a shop made bass nut or the wound strings on a guitar nut.

 

[j-stylez]

Much better, strings half covered on E, a bit more like 2/3 covered towards G string.

Also, got some Initial reshaping on the headstock end done. I want to round the top left and both bottom corners a little more I think. Have to work with the available Material, but kind of like this style. Looks a bit like Elvis' haircut.

 

[j-stylez]

I'm thinking about finish options. I have clear nitro and some suitable amber tint. I'll redo the headstock as well and give it my own logo. Now the thing is, I'm unsure how to go about the fretboard. I dont want to sand between frets, but if I just spray the rest of the neck, I have to stick to clear transparent lacquer.

I dont like the bright white look, so I might just scuff the thin PU on the fretboard with some steel wool and do the whole neck with tinted lacquer, so that I get a uniform shade.

Any thoughs on this?

 

[j-stylez]

Meanwhile, I have played this bass a lot and optimized the neck profile to my liking. That also included making the transistion to the fairly wide heel more gradual. I also tidied up the headstock and gave it a complete fret job - level, dress, crown, polish.

Then I finally had the time to get my new compressor and spray gun set up to get this thing lacquered with nitrate nitrocellulose lacquer.

I use a small compressor, set that to about 5 bar, then a pressure Regulator and demoisturizer set to my spraying pressure. That's about 2 bar. Then a 1mm nozzle on a cheap hvlp gun. I practiced a bit to get the fan, material and airflow right. Still working on it, getting there slowly. Thinning ratio has a strong effect on the required settings. I use about 30-50% thinner with my lacquer and go as light as possible.

Since the PU coating was thin, it was easy to sand it off the remaining exposed parts. On the fretboard, I only scuffed the finish with abrasive pads and some steel wool so that the lacquer would bond. No way I am sanding between frets - that would be quiet a nightmare

I gave it about 5-6 coats of clear nitro all over. Then followed with tinted lacquer, about 3 coats of the same nitro lacquer, but mixed in some amber tint. This is the cool Part about using a gun vs. Rattle cans. It's so cool to mix your own tint.

Had to repair a mishap on the face of the headstock - a run in the tinted coat, on the top 5 cm of the headstock ...which I tried to fix with some thinner, thus made it worse. But I Managed to carefully sand that with 320 grit after a bit of waiting, then misted that area with some stronger tint and now I think it has blended in nicely. Since that maple is not the most uniform color, it could pass as some wood discoloration.

It has a stronger amber tint than the pictures seem to indicate, they look brighter due to the weird lighting and camera.

Now it's gassing off a bit, and tonight I will follow up with a few more clear coats. Then tomorrow morning a final clear coat, maybe with some retarder so it all flows out nicely.

 

[j-stylez]

These pictures show the color a bit better:

Once the final clear Coats are on tomorrow, it will gas off for 10 days. Then I will add a decal/logo to the headstock and probably clear Coat the headstock again to get the logo flush.

 

[j-stylez]

Getting there... I had some pores showing through the thin nitro after 10 days of drying (everywhere Except the fingerboard, because there I had left the thin poly on as a base coat). So I decided to top off the coating with shellac and pumice, a light french polish.

 

[j-stylez]

Cut that huge ugly bridge baseplate down to something prettier resembling a real ernie ball bridge. Why hide so much of that actually quiet nice sunburst? Probably to avoid lawsuits

 

[j-stylez]

More progress...

 

[j-stylez]

Getting the decal ready... Ye I made some extras in case I mess up

 

[Beej]

I like your treatment of the baseplate, it looks great.

 

[j-stylez]

Flipped the decal and painted it gold with a small brush, then in the next step I'll slide it on with some water mixed with a drop of glue.

Slide it on. This was not perfect, took me too Long to get some bubbles out. 95% is rough for me, it's a Player and not a showcase instrument.

 

[j-stylez]

Not going to sink the decal in lacquer - too much work for an Almost invisible improvement. Flattening the edges with vinegar worked really well. So this is going to stay uncovered like old fender guitar headstock decals. I've got plenty backup decals that may quickly be applied should this one deteriorate

The only thing I might add now is a custom string tree to cover the G String as well, to slightly shift that inwards above the nut.

Really like this new look and the neck feels great. I have to pat myself on the back for the fret job, it's super smooth.

 

[flavio-san]

One day I will do this too, I've been thinking of it for a long time.
F

 

[willofcrot]

Very great job
I also would like to buy this Bass second hand in order to mod it.
I really like playing on shortscales, which kind of neck would you put on this one to have a short scale ?
Thanks and one more time bravo

 

[j-stylez]

Thats hard to say, you need a neck that matches the neck pocket. Then depending on the neck, you might have to move the bridge and pickup Position to fit the new scale length and intonate correctly. It may be difficult to find a neck that just fits right out of the Box.

For guitars, there are scale-conversion necks e.g. ti get a 24.75" scale on a strat or tele. But these are always designed with a particular target guitar type in mind (due to the neckpocket/bridge suitability mentioned above).

I have no idea what the harlex benton neck pocket specs are, but you can probably search that.

Personally, I like slim J-style necks. Maybe if you are lucky, you can fit some kind of jaguar style neck on there. But I honestly dont know.

 

[willofcrot]

Thats hard to say, you need a neck that matches the neck pocket. Then depending on the neck, you might have to move the bridge and pickup Position to fit the new scale length and intonate correctly. It may be difficult to find a neck that just fits right out of the Box.

For guitars, there are scale-conversion necks e.g. ti get a 24.75" scale on a strat or tele. But these are always designed with a particular target guitar type in mind (due to the neckpocket/bridge suitability mentioned above).

I have no idea what the harlex benton neck pocket specs are, but you can probably search that.

Personally, I like slim J-style necks. Maybe if you are lucky, you can fit some kind of jaguar style neck on there. But I honestly dont know.

Thanks a lot for your quick answer. Am going to search that.