Probably the most frequently asked question I get is "how much tolex do I need for my cabinet". Often times, in reality, I don't think their question involves measurements and sizes as much as it does layout and patterning. In other words how do you take a piece tolex, which when layed out flat on your workbench (or dining room table) is a one dimensional, flat piece of vinyl, and wrap it around a 3 dimensional wooden box (and make it look good). Therefore this article should probably be read in conjunction with our "retolexing project" tutorial. This will really help you get a grasp on the whole subject. After all, the purpose of this article isn't to tell you how much tolex you're going to need, but to help you figure it out yourself.
"So, how do you do this?"
This isn't always an easy question to answer as not only are there dozens of different styles and sizes of cabinets, and many times there's more than one way that the cabinet can be wrapped, which can alter the amount of tolex that's required to do the job. For example you can sometimes get away with purchasing less tolex simply by putting a couple of extra seams in the tolex. There is, of course a tradeoff. The seams can be a source of frustration as they can be difficult to hide and can sometimes come loose or separate over time leading to all kinds of problems. Also, while some tolex patterns hide the seams fairly well, others like snakeskin or alligator do not, as most often the pattern will not line up at all, making the seams stick out like a sore thumb. All cabinets will have at least one seam, but you should avoid having any more than necessary and you should plan the layout so that the seam(s) are in the most inconspicuos place possible (like on the bottom side of the cabinet). If you're redoing a cabinet you can often see where the factory seams were when you strip the old tolex off (yes the old tolex has to come off!). Putting your seams in the same location as the factory seams is almost always a good idea.
If it's a typical guitar combo amp or 2x12 speaker cabinet (Like the crude drawing below) then it's probably an open back cabinet or a cabinet with a removable back panel. This makes the job of measuring and installing tolex a lot easier. The easiest way to wrap this type of cabinet is to use one long piece of tolex to wrap completely around the shell of the cabinet starting at the bottom and wrapping all the way around the bottom, side, top and other side, with the with the ends of the piece seaming together on the bottom side of the cabinet. So if you took a typical 2x12 cabinet or combo amp which might measure something like 26in wide, 22in tall and 10in deep, you would need a long narrow strip of tolex at least 96in long (26+22+26+22=96). You would of course need at least a couple of inches to overlap and double cut the seam, and don't forget about the back panel if needed.
You could also do this type of cabinet with four separate pieces of tolex -one each for the two side and be top and bottom, with seams at the corners, but I don't think this is best option, as the seams are normally the biggest problem areas in tolex application.
Now, up until a few years ago, you could only purchase tolex in 54in wide rolls and was sold be the linear yard (36in) so to get the 96+ inch piece to wrap the cabinet above you would have had to order 3yds (108in) of tolex 54in wide. This meant that you were purchasing a 54in x 108in piece which is way more tolex than you actually needed. Many suppliers are now offering tolex in narrower 18" and 34" widths, which can save you a lot of money. In the case of the 2x12 cabinet above you could order 3yds of 18" material. You would still need to order another yard of 34" material to cover the back panel but this is still a lot more cost effective than ordering a 54in x 108in piece. Speaker Builder Supply even sells tolex in handy 2x12 kits which includes both the 18"x108" piece and a 24"x36" back panel piece which can save you even more. We even sell 4x12 kits for larger cabinets. The thing that you really have to measure carefully is the depth of the cabinet. Most cabinets are only about 10 to 12 inches deep so an 18" strip is normally wide enough to cover the depth plus allow a couple of inches to wrap around the front and rear edge of the cabinet, but if your cabinet is extra deep and/or has an extra wide front or rear lip, then you may have to order a wider 34" piece.
If your cabinet is larger or smaller than the 2x12 illustration, just alter your measurements accordingly. For example a typical 4x12 cabinet is normally about 30in x 30in x 11in., so you'd need a strip of tolex at least 120in long (30+30+30+30). Of course, just as in the 2x12 example above you still have measure for depth, and a back panel.
So what if you're working on a
cabinet with a solid non-removable back?
Yeah, like the pesky front mounted bass cabinets. As you can imagine, this makes things a little more difficult. Cause' now the tolex has to wrap over a 5th panel with no breaks, and make it look like one piece. This is also where it gets difficult for me to explain to someone how much tolex they need for their cabinet, cause there's normally at least 4 different ways these types of cabinets can be done.
So lets take a look
So as you can see, there's often more than one way to wrap a closed back cabinet with tolex, and normally one of the four above will work. It's just a matter of figuring out which will work best for your particular cabinet design. Normally speaking, you'll want to choose a layout that will give you the least amount of seams and/or at least put the seams where their going to be the least noticable. On a closed back cabinet there's no way to avoid having a bunch of seams, so you may want to stay away from any kind of a patterned tolex like snakeskin or zebra stripe, as the pattern will never line up at the seams.
Of course, there's always going to be those oddball cabinets with funky angles that are going to require some mad tolexing skills to pattern out. I find that it's sometimes helpful to get some heavy weight paper to pattern out the project. Poster board works good for this. You might have to tape a few pieces together to make it large enough to draw out a full size pattern. Lumber yards sell a product called patterning felt which flooring installers use to pattern out vinyl flooring. This works great, but you normally have to buy a full roll, but it's a lot cheaper than scrapping out expensive pieces of tolex. Laying out a pattern this way would be really useful on something like an angled monitor cabinet, or something with odd angles.
And speaking of cabinets with odd angles, I get a lot of questions about those big Ampeg 810 SVT cabinets, so I'm including a rough drawing to help you get an idea for how you might do an installion.
This drawing is for a one piece install similar to most Ampeg factory jobs. One long piece of tolex wraps around the entire perimeter of the cabinet (bottom, side A, top, and side B). Most of the cabinets were roughly 48" tall 30" and 16" or so deep, so you would need a piece of tolex at least 156" long (48+30+48+30) and a couple of inches to overlap and double cut the seam where the two ends meet (should be at the bottom of the cabinet). This same piece must be wide enough to wrap the front lip of the cabinet and to wrap around and seem together on the back side of the cabinet. You can do this with 34" wide tolex but it's cutting it close so you'll have to use caution to get the tolex lined up perfect when wrapping. To get the 156" length we'll have to order 5yds.
So 5yds to 34" material would be required.
This drawing shows the seam pattern as view from the back of the cabinet
There is an alternative method when doing these cabinets. You can do a 3 piece install which might save some yardage, but you'll have to start with 54", but you'll just need just 3yds of material. Out of the 54"x108" piece that you order you would cut one piece to wrap the back, bottom and top of the cabinet (represented by the yellow part of the drawing. This piece would need to be about 30" or so wide. This should leave you enough material to cut two strips for the side, which would need to be about 50" long and wide enough to cover the depth of the cabinet plus 2" or 3" to wrap the front lip and an inch or so to wrap around the back edge of the cabinet and seam to the back/bottom/top piece.
I don't care for this method as much as the first, because with the first method most of the seams are on the back side of the cabinet, but this method is an option.
It would require 3yds of 54" material.
So there you have it. Any questions, comments or suggestions, just us the Contact US form. Thanks