Building a cab or combo shell

[Bieworm]

Since I've built plenty of cabs and combo shells in all different colors and sizes with a fair amount of succes I've been asked to open a thread on this subject.
I hope this can be an interesting source of information for people who have built and amp and want to do the woodwork and tolexing / grill cloth application themselves.
As expected there are a lot of things that can or might go wrong when building a cab or combo. There are things to be considered before you haul out your tools and start working. The next few weeks I will post tutorials of all separate phases, starting from the beginning...

[AussieTim]

Ok Ive got this far and the next step is covering the actual cabinet, Im a bit worried about how to go about the top vent slot which is why I did a cutout in the back was not really happy with the result, the only way I can work out to do it better is to make sure the width of the slot is more than twice the thickness of the wood. Marshall built these things with a 1 inch slot on half inch timber so how did they het the covering nicely in the slot? I do not think I have done woodwork since high school so it is a bit rough and I have never attempted upholstery.
Tim

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[Bieworm]

Ok Ive got this far and the next step is covering the actual cabinet, Im a bit worried about how to go about the top vent slot which is why I did a cutout in the back was not really happy with the result, the only way I can work out to do it better is to make sure the width of the slot is more than twice the thickness of the wood. Marshall built these things with a 1 inch slot on half inch timber so how did they het the covering nicely in the slot? I do not think I have done woodwork since high school so it is a bit rough and I have never attempted upholstery.
Tim
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Hey Tim

Do you have a hand mill? When you mill out the underside of the top panel around the area of the vent hole you’d be making the panel thinner, thus less need for slack length. It also looks nicer with the grill closer to the surface. When you apply the tolex be careful and slow. Use a hairdryer to soften the tolex.

[Bieworm]

This is a principle plan of how I do an 18 watt Blues Breaker type cab (top controls)

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[Joe Blow]

I'm sure going to follow this thread!
I've built several cabs over the years, both sound reinforcement, and guitar/bass, but always interested in what others, (probably with real woodworking skills), put together. My last few cabs, I've used biscuits to join the panels, and they are holding up pretty well!

[TriodeLuvr]

I've done a fair amount of woodworking, including building my own oak audio rack. Cabinet work is really tedious, though. If not for the fact someone gave me an empty Peavy 1X12 combo, I still wouldn't have a DIY guitar amp. Wish I could trade chassis metal work for cabinetry with someone local.

[Bieworm]

I've done a fair amount of woodworking, including building my own oak audio rack. Cabinet work is really tedious, though. If not for the fact someone gave me an empty Peavy 1X12 combo, I still wouldn't have a DIY guitar amp. Wish I could trade chassis metal work for cabinetry with someone local.

Yeah… but your metal work is off the planet type good!

[TriodeLuvr]

Yeah… but your metal work is off the planet type good!

Hey, thanks for that!

A quick question - How does everyone feel about combos and heads with a wood finish? DIY Tolex is really a deal killer for me. OTOH, I have a stack of solid white oak boards (shelving) I could work with. It's tough wood, and I'm thinking a light finish wouldn't show dents and bruises as much as darker stains. Is it worth building this way, or is Tolex essential for a professional quality amp? I do realize wood affects the sound, and a hardwood like oak might not be best. I'm thinking mostly about head units here.

[Bieworm]

Yeah… but your metal work is off the planet type good!

Hey, thanks for that!

A quick question - How does everyone feel about combos and heads with a wood finish? DIY Tolex is really a deal killer for me. OTOH, I have a stack of solid white oak boards (shelving) I could work with. It's tough wood, and I'm thinking a light finish wouldn't show dents and bruises as much as darker stains. Is it worth building this way, or is Tolex essential for a professional quality amp? I do realize wood affects the sound, and a hardwood like oak might not be best. I'm thinking mostly about head units here.

Getting a good tolex job done yourself takes practice. But wood.. I’m not a big fan of the look to be honest. Oak seems like a pretty heavy option … I use pine
And think about it… a lot of great sounding amps from the past were made with pressed particle wood..

[Joe Blow]

I've always wondered if tolex on the wood doesn't dampen the resonance.
Wood in my area is pretty expensive, so the guitar cabs I've built are plywood. My PA cabs were made with OSB, really heavy!

[TriodeLuvr]

Getting a good tolex job done yourself takes practice. But wood.. I’m not a big fan of the look to be honest.

No argument there, I really like the look of Tolex too. But I already have this oak, and it's very tough. I've used a small amount for wood trim panels on stereo amps. Maybe I'll try to build a head amp cabinet with it later this year and see how it looks. Meanwhile, I'll keep an eye open for any broken amps that can donate an empty cabinet.

Jack

[JMPGuitars]

I'll add these in the download section, but they're relevant here:

files/2x12cabwiring.pdf
files/2x12-parallel.pdf
files/2x12-series.pdf
files/5e3_cabinet_sheet_3.pdf
files/5e3_cabinet-sheet_1.pdf
files/5e3_cabinet-sheet_2.pdf
files/18_watt_head_chassis.pdf
files/18watt_2x12_cab.pdf
files/18watt_head.pdf
files/18wattcabinet2.pdf
files/18wattdimensions.doc
files/chassis_dimensions.pdf
files/chassis_dimensions-metric.pdf
files/head_cab_23in.pdf
files/1958_combo_cabinet_drawings.ppt
files/1960a-slant-cab_rev1.pdf
files/cab_tweed_deluxe.pdf

[TriodeLuvr]

Question - When you design a cabinet, do you consider the dimensions for the purpose of having an aftermarket cover readily available? Or does it just go without saying that most DIY cabinets are copies of popular commercial models?

[JMPGuitars]

Question - When you design a cabinet, do you consider the dimensions for the purpose of having an aftermarket cover readily available? Or does it just go without saying that most DIY cabinets are copies of popular commercial models?

Both are good options, but you don't have to. Covers aren't that hard to make, and there are services out there that will make them for you. I've used digitaldeckcovers.com to make covers for different things for me, including my oscilloscope, mixing boards, keyboards, etc. I'm sure they could do amp covers too, though I'm not sure if they would do handle cutouts or not. EDIT: now that I think of it, DDC I think would do handle cutouts, but you have to give them measurements and a drawing.

Besides that, I think people design cabinets to match preexisting designs, so there's likely covers available anyway.

[Bieworm]

Ok… I have an order from someone who wants me to build a head cab and a speaker cab for his Suhr Bella combo, which he finds too heavy to haul around. So coming soon are more relevant building tips for 18 watters, instead of the slanted faceplate cabs I always build for my amps.

[Joe Blow]

https://mdbcovers.com/
Mike is a great guy, and has built several for non standard cabs.
(Reasonably priced too!)

[Bieworm]

howdie y'all!
Josh asked me to make a guide / tutorial about combo cab building. The 1st issue was for a F*nder type combo, but I have changed it to a more appropriate type of combo cab build.
Pictures of actual building in progress and special tutorials about tolexing and grill cloth-ing will follow in a while...

preparations front controlled combo cab.pdf

[Bieworm]

For anyone who’s interested, this is my method for getting a well aligned front top board. Instead of putting a lot of effort into hand cutting the recess for a front controlled combo cab, I make the top board 18mm narrower than the rest of the boards. Then I cut 2 identical wedge forms and glue them to the front side. Works like a charm!

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[Bieworm]

Finished

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