tolex is not my friend

[muchxs]

Ive seen the no stretch many places.....

At a glance it looks like a good idea to stand the cabinet on the bench and wrap tolex around it. Do the opposite, lay the tolex treated with your adhesive of choice on the bench and roll the cabinet over it. You'll end up with wrinkles and air bubbles under the tolex but that's what creates your slack. Roll them out. The faux leather pattern in the material will take up the slack.

under stand the need for an untrasharp blade...... had an issue with ragged
cuts.... the miter worked but did have a "precision" issue...

The primary cause of open corners is tight tolex. You have an afternoon to cover your cabinet then your cabinet has 24/7 for the rest of your life for the tolex to snap back to its original dimensions, it usually happens quicker than that. This is a good time to state that complicated multi-color covering jobs are much less your friend than a single color. If you butt two colors together that seam had better not move, ever.

The secondary cause (of open corners) is a ragged cut. This is where practice is key. It might look like the finished corner is a straight cut, it's actually a French curve. Mr. Le Blanc... you were born to cut French curves! This is where practice comes in. Once you've done this enough times you know where your start point is (easy), where your finish point is (not as easy) and the shape you need to cut (the hard part).

and hard not to do..... its very easy to
try force

There are eight corners per cabinet and I usually do a hatchet job on at least one of them. The trick is to warm up on something less critical, start with the lower rear corners of the cabinet then work your way towards the visible corners. Or cover some back panels first, those are mostly straight cuts.

[Andy Le Blanc]

this last one I laid out the material on the floor to apply the adhesive...
and ended up with slack..... which made me worry.... I did think ahead to use
a center line on both the box and the tolex...... that helped a bit to keep things centerd....
the slack was easy to smooth even by hand.....
I have seen cabs and pictures with a large curved seam on the largest visable seam
on the bottom.... but a rounded corner...curved surface , curved cut?......
looking ahead to the type of corner before your there is where you need to think a bit....
been looking at a lot of old cabs on-line.... many cab types have no curved edges.....
I would expect a very linear approach to cut and shape corners...
as you said a miter..... for flat angles.....
the tweed cut looks to match fabric but I noticed it also covers a flat edge...
the round over on the top outside edges to the flat angle cut above the control panel on the fenders...
someone was thinking ahead to a easy and consistant product there...

[muchxs]

I have seen cabs and pictures with a large curved seam on the largest visable seam

On a tweed style cabinet there will be four visible seams, two on the top, two on the bottom. The cabinet can be dressed up by cutting grooves for piping but the fastest way to cover the cabinet is to do a straight overlapped seam like Fender did it. Fender's design philosophy is the benchmark IMHO, make it solid and make it work correctly first. If there's any time and money left over make it pretty.

Pre-CBS and under the leadership of Leo himself Fender was a powerful company that turned out spectacular instruments and amps. Emulate Fender's pre-CBS manufacturing philosophy and you can't go wrong.

a rounded corner...curved surface , curved cut?......
looking ahead to the type of corner before your there is where you need to think a bit.......

It's a French curve. A French curve isn't a constant radius. The cut starts out straight (ish) then there's a little hook on both edges as it finishes. You can actually get away with a sloppy cut but the shape must be approximately correct, otherwise there will be an open spot on the corner.

been looking at a lot of old cabs on-line.... many cab types have no curved edges.....
I would expect a very linear approach to cut and shape corners...
as you said a miter..... for flat angles........

A roundover at the cabinet edge dissipates force if the cabinet gets banged around making the covering job more durable. No roundover means the sharp edge of the cabinet will cut the covering on impact. Remember form follows function. A good design will still look good 50 years from now. I expect the relic look won't last so shredded covering isn't value-added.

the tweed cut looks to match fabric but I noticed it also covers a flat edge...
the round over on the top outside edges to the flat angle cut above the control panel on the fenders...
someone was thinking ahead to a easy and consistant product there...

That "tweed" cut is deceptive. I can do "mitered" corners much quicker than "tweed" corners.

The "tweed" corner has the added benefit of moving the seam away from the most vulnerable part of the corner.

[Andy Le Blanc]

I was working on some flat pieces the other day and noticed that the tolex
had pulled back from a flush edge.... I was very aware to not stretch...
and will give more time next time before making a finished edge.....
it was the baffle that protects the power tubes..... I put aluminum tape
on the side that faces the tubes and needed the finished edge...

anyway..... the shink was only on the order of a couple three 64th
but it happend one way..... and I was wondering which way it tended to
move..... with or across the fabric weave?.......

Tolex and contact cement are very much "live" until the driers in the cement
are finished....

nice pics over on the TW side....

[muchxs]

I was working on some flat pieces the other day and noticed that the tolex
had pulled back from a flush edge.... I was very aware to not stretch...
and will give more time next time before making a finished edge.....
it was the baffle that protects the power tubes..... I put aluminum tape
on the side that faces the tubes and needed the finished edge...

I use Nomex board for heat protection. It looks like cardboard except this cardboard is made of DuPont Nomex fiber. It's very hard to get but I have access...

anyway..... the shink was only on the order of a couple three 64th
but it happend one way..... and I was wondering which way it tended to
move..... with or across the fabric weave?.......

IMHO it has nothing to do with the cloth backing. The solvent in the contact cement migrates into the vinyl, it grows about 1/8" per foot in all directions. Just one more little thing to add to the fun factor...

Mojo had a batch of discontinued covering material (blue) a while back with polyester backing. The only way to get that stuff to stick was to nail it on...

Tolex and contact cement are very much "live" until the driers in the cement
are finished....

It's very important that you don't have any wet spots in the contact cement. Most of the solvent evaporates within 24 hours. If it was up to me I'd do all my covering in New Mexico or Arizona, hot and dry would make my life easier. We don't have hot and dry, there are still a few patches of snow outside my workshop...

[Andy Le Blanc]

understand "dry" ...... part and parcel of doing the chore
its good to know that backing materials really matter.... cant make every thing stick
I magine it would be an issue of "solvent"... getting more creative with
differnt materials would mean a differnt adhesive.....
good little piece of info..... I would have thought opposite......
first thought was shirink not swell.... every little bit is good
the next job is tolex but ive been eye'in other fabrics to play with for giggles..

[muchxs]

the next job is tolex but ive been eye'in other fabrics to play with for giggles..

When you get really good try one in leather. With leather you don't have to worry about the interaction of solvent and vinyl.

[FunkyE9th]

Not to hijack the thread but... what's the difference between Tolex and the Vinyl that you can get from a fabric store? I saw some on clearance at a fabric store (seemed pretty heavy duty) and thinking of using it for my 1st tolex attempt.

-FunkyE9th

[Andy Le Blanc]

Ive eyed' the stuff too..... it seems much softer..... maybe a synthetic backin
I was thinkin of doing test patches..... before commiting

[rfgordon]

I can speak a bit to the vinyl vs tolex thing. First off, the product we generally know as tolex is fairly hard and stiff. Some versions, like snakeskin and marshall-style elephant, are thicker or stiffer. In my experience, a really good water based glue (like Mojo) is key. Some solvents will interact with the material in unpredictable and very icky ways.

With regard to vinyl materials, be aware that there are lots of types. I have used several types of auto upholstery grade material from www.yourautotrim.com with excellent results. Their stuff generally meets pretty tough abrasion resistance standards, so it holds up well. But this stuff can be a bit stretchy, and, again, water based glue is key. If you can get the spray on contact cement that auto upholstery guys get in the giant, propane tank-size cans, that works well. Anything else solvent based works poorly. ANY aerosol can adhesive is gonna ruin you day.

Furniture grade vinyl is very soft, stretchy and prone to tearing. many of these types have thick fabric backing which can separate from the vinyl, but stay stuck to the cab. Yuck, yuck, and double yuck.

I had a guy ask me to quote a price for an ultra lightweight 20 watt, 1x12 combo. OK, so light amp chassis and neo speaker are no problem. I did actually find a source for carbon foam core and carbon fibe sheet, so I could build a cab that would weigh about 3 lbs. Cool, right? For some reason the guy balked at the price!! Over $1000 for the cab materials alone! But wouldn't that be so much cooler than tolex?

[candh]

Lot of good info guys. And just for something a little different....

In the future, for a challenge you might want to try doing corners like I do them..ala Komet. They take a while to get down but are sure attractive and draw a lot of positive attention. My amps certainly fall into the "must be babied" category though.

http://i142.photobucket.com/albums/r107 ... G_6608.jpg

or

http://i142.photobucket.com/albums/r107 ... rtone2.jpg

or

http://i142.photobucket.com/albums/r107 ... stlogo.jpg

Chris

[Andy Le Blanc]

thats fantastic....... hadn't seen that yet
Now thats pipping and tolex in a channel cut into the cabinet?
on the corner like that, does it compromise the strength of the cabinet?

[billyz]

Pretty sweet piping work.

[candh]

Thanks for the compliments.

Yes, the channels are cut at 45 degrees. Cutting these mitres in 18mm box jointed material poses little compromise in structural integrity. I wouldn't be as confident with thinner stock though.

[Noel Grassy]

Lot of good info guys. And just for something a little different....

In the future, for a challenge you might want to try doing corners like I do them..ala Komet. They take a while to get down but are sure attractive and draw a lot of positive attention. My amps certainly fall into the "must be babied" category though.


Chris

Nice work Chris! What's your technique for cutting the kerf all the way around the miter to the front of the cab? You can't possibly do that freehand on the tablesaw, right? Is the channel/kerf made before the cabs are assembled? I'd love to do one using your technique. TIA, Noel.