Marshall 100W 4x12 Cabinet Clone

[Neve1073lover]

Got so carried away with my Neve thread, I thought I would show my Marshall 4x12 100W build:

Fingerjointed the front panel. Never Again...

Greenbacks. Used 4 x 25W 8 ohm. 2 lots of 2 in series (16 ohm), then in parallel, making an input impedence of 8 ohm:

Left input is mono 8 ohm, use both and automatically changes to stereo 16 ohm.

More fingerjoints:

Salt and Pepper grillcloth:

Proper Tolex design:

Gold piping:

Inside:

Had enough wood etc left over to make a 2x12 (both 16 ohm speakers):

I will load some totally finished shots (corner rubbers and 'Marshall' logo) later tonight.

Happy to provide dimensions.
Garry

 

[thane1200]

I don't know much about guitars, or cabs, but that is some nice craftsmanship. Congrats on the fine build!

 

[thajeremy]

what did you use to make the cuts on the corners?

 

[Neve1073lover]

what did you use to make the cuts on the corners?

For the fingerjoints, I used a dovetail jig, but with a straight router bit.
You need to have a bit that is the exact right size for your jig. I had to grind down one of mine to get the exact size.

I took the guide off the jig and reversed it so that it stuck out in the air and placed the wood under it. Could only do about 18 inches at a time, then move the wood along, and lined up on the centre of one of the jig fingers.

The problem with working out the bit size is that the jig 'fingers' may not be the same width as the jig 'gaps'. the gaps are often wider.

If they are the same width, then the bit needs to be that width.
If they are different, then the bit needs to be half of the combined finger plus gap width.

You can buy jigs that are adjustable and will do both finger joints and dovetails. Much more expensive though.

Also REMEMBER to slide the router OUT of the jig. If you lift it at any time, it will eat the jig.

 

[jrhoden]

wow

very nice build man !

 

[solaris1982]

Very Impressive!

Though, if I were to build something as impressive as that, I'd want to put my own sig on it, not another company's logo! (Plus, isn't that technically illegal?)

 

[Neve1073lover]

Very Impressive!

Though, if I were to build something as impressive as that, I'd want to put my own sig on it, not another company's logo! (Plus, isn't that technically illegal?)

probably....

 

[omtayslick]

Yeah, but it helps the resale value.

 

[solaris1982]

That would actually really make it illegal. Copyright infringement of some sort I think. Light or Muttley brought this up in a thread about someone wanting to put Fender decals on a warmoth neck I think.

Either way, the cab looks spectacular. You wouldn't happen to have any construction plans for it that you'd like to share, would you?

 

[Neve1073lover]

That would actually really make it illegal. Copyright infringement of some sort I think. Light or Muttley brought this up in a thread about someone wanting to put Fender decals on a warmoth neck I think.

Either way, the cab looks spectacular. You wouldn't happen to have any construction plans for it that you'd like to share, would you?

I measured up a genuine Marshall, so is very close. I will put something together and post ASAP.

 

[Neve1073lover]

Dimensions and How To

I suggest you read this and look at my photos.

Here are the dimension of the pieces. Note that this is for fingerjoints.
If you are going to butt joint, then reduce both SIDES (not the bottom or top for strength) by twice the wood thickness:

I used 19mm thick ply. Try and get ply that does not have cavities.

I used 3/4" wide strengthening pieces inside that were screwed and glued.

Measure the internal dimensions and make the rest to fit.

Make sure that the top 2" front piece aligns at its BACK and then plane it down so that the top of the cabinet is flat. This makes it a bit thinner in width, so you could make it 2 1/4 " wide or so to start with if you want perfection.

Use 'T' Nuts (they hammer in) on the front panel so that you can mount the speakers without taking everything apart.

I added strengthening wood at the bottom to take the caster bolts. Use 'T' Nuts again. Leave a space at the front of any such strengthening to allow you to slip the front panel in. Handles must not be on yet....

You will need to notch the top edges of the front panel to allow for any corner joint strengthening pieces.

I put gaffer tape around the edges of the front panel and also across the centre joint to cover any finger joint gaps.

I attached the speaker cloth to the front panel with staples.

I attached the piping to the inside edges of the speaker box 2" strips with staples.

Put 3/4" strips around the inside of the cabinet to mount the back panel onto.

Stop the side strips about 6-8" from the top so that you can slide the front panel in and down. Test placement of the front panel and cut the side strips shorter (at the top) if you need to.

Glue on the Tolex. A story unto itself. Practice edge and corner cutting with waste cloth etc before using Tolex. Actually very tricky on the front of the cabinet (the corners). The glue softens the Tolex and you can work it a bit.

Slide in the front panel and screw through its edges into the 2" strips that make the front of the cabinet. Make sure you do not go right through...

You can then mount the speakers etc.

Hope you can understand all this....

 

[Neve1073lover]

More Pics to Help Understanding

The strengthening piece for the casters with 'T' Nuts. I cut it in half to get the casters wider apart:

The inside showing the corner strengthening at the top, a notch in the front panel, and the back panel mounts that stop short so the front panel can slide in:

The caster mounts and the front panel in front of them. They also strengthen the bottom corners:

The front panel speaker 'T' nuts before I sprayed them black and gaffer tape.:

Finished (with dent where I leant something on the cloth and no rubber corners yet):

Garry

 

[JG96]

was it hard to cut the holes for speakers and what kinda saw did you need?

 

[Neve1073lover]

was it hard to cut the holes for speakers and what kinda saw did you need?

I cut a template in some thin plywood that I then used to mark out a hole and measured that it was accurate. Allowed me to get 4 accurate holes marked.

Then drilled a hole inside the circle that was big enough for the jigsaw blade to fit in. Then jig sawed, and hand sanded.

Also routed a radius edge to the hole on both sides of the hole. Could just hand sand.

If you put any screws in, like I did for the front strips to hold them while the glue dires, take them out when you rout a radius. Then put them back in for strength.

 

[CMunch]

Nice build,

 

[ausrock]

I was trying to figure out your wiring from the pics but couldn't. Is there any chance of putting up a wiring mud-map for the 4x16 ohm to 8 ohm impedance.

Great build BTW ...............the best sounding quad I've ever heard was a mate's Boogie BUT it is an old model, 1/2 closed 1/2 open back 600watt and very compact compared to our Marshall quad. I've been toying with the idea of making a copy but I don't know whether I could still get the same EV 150 watt speakers so would probably have to do with the Etones and Celestions I have lying around.

 

[Neve1073lover]

I was trying to figure out your wiring from the pics but couldn't. Is there any chance of putting up a wiring mud-map for the 4x16 ohm to 8 ohm impedance.

Great build BTW ...............the best sounding quad I've ever heard was a mate's Boogie BUT it is an old model, 1/2 closed 1/2 open back 600watt and very compact compared to our Marshall quad. I've been toying with the idea of making a copy but I don't know whether I could still get the same EV 150 watt speakers so would probably have to do with the Etones and Celestions I have lying around.

I said above 'Used 4 x 25W 8 ohm. 2 lots of 2 in series (16 ohm), then in parallel, making an input impedence of 8 ohm:'

The 'trick' to the mono/stereo is in the connectors. Some photos and explanation of how they work.
You will see 3 (this is a stereo plug, could be 2 for mono) metal tabs that go across and contact the wire connectors on the other side:

A photo with a plug inserted shows they are lifted up, and do not contact. The plug is connected to the other side's wire contacts only:

A photo of the other side:

The schematic: