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I have built a lot of benches, my last shop had 24 workbenches. Over the years, my approach changed with experience.
The surface needs to be anti-static, easy to clean, durable, hard and dense. Normally people use particle board and cover it with indoor-outdoor carpet but after a short time it looks bad, easily scratches customer units, becomes hard to clean and makes the whole shop look dirty and unprofessional.
The best and cheapest method of making a pro style bench, what I found, was the molded laminated counter top with included molded splash panel, which sells for about $3 a linear foot in lengths up to 12 feet. It is resistant to chemicals, solder burn, soldering iron accidents, and is very rigid so it is requires less massive support assemblies than 3/4 in or 1 in particle board. Cleaning is a snap, just brush it off or once a week or which there is a spill, is 409 and shop towels.
No unit touches the bench surface however, every unit is placed on a carpet sample, usually 22X16 inches which sell for $1-2 each with nicely bound sewn edges from carpet remenant or carpet showrooms. When one gets burned, toss it or use in the garage for something. The backing is tough and slides easily on the smooth(usually lightly textured) laminate surface so a heavy unit can be slid out of the way on a typical 8 foot workbench.
A matching height hard rubber AV cart allows a heavy unit to be taken from the shop lobby to the bench by the counter girls without ever having to lift it or potentially drop it. The unit would simply slide from the cart to the bench on its own carpet sample. Customers really appreciate it when their unit is cared for and is not subjected to the risks associated with conventional shop practices. Here are examples, the workbench in my spare bedroom in my apartment here in Russia and one of the AV carts. The AV carts are strong, supporting over 300 lbs and are very useful around the shop. My old shop had dozens of them. A large mixer could be laid over two of them and still able to rotate it and single handed manipulated. A large power amp could stay on it and never be moved to the bench. One of my benches had no work surface, and was intended for having both the tool box and unit under test to stay on AV carts where they could be moved as needed to get at the best angles. They are great for weighted key keyboards. Being rubber, they are never going to scratch a customer unit. My last large shop was houses in a large R&D style modern building that had thick commercial carpet in all but the warehouse. The large wheels of the carts helped transporting equipment over the thick carpet and the carpet meant no units were damaged from accidental drops.
Other considerations about benches include access to the rear. It was not uncommon to add more test gear or remove a unit for calibration so access to the rear of the bench was a very welcome difference between my benches and those of most shops. Being freestanding, the shop can be rearranged as needed when product orientation changes or when new layouts are desired. Also, make the bench large enough to allow keeping a unit disassembled while waiting for an estimate approval while working on a second unit. Since my standard benches were 8 feet, which might be too short to have two large units in disassembled states, I build extra benches for each tech. We had 15 techs and 24 benches, but some techs worked on things that were small and self contained like DAT/DA88 format decks which did not need more space. Leaving a larger unit on an AV cart allowed it to be rolled away into a storage area, still disassembled, if it was waiting on parts. The unit rolls back to being next to the bench when the part comes in. The repair is completed without ever leaving the cart and never but one reassembly. That improves shop throughput a lot. A good work bench has duplicates of some important test gear, like a scope and signal generator and metered variac. That allows close monitoring of a unit being burned in to detect time or temperature induced intermittents while working on another unit. If you are doing a lot of amps, a dedicated burn-in rack is needed. It can be fan cooled, with cooled dummy loads, have programmable signal source, limit alarms etc. Every power amp or guitar amp should have a reasonable burn-in with re-biasing done after after burn-in if a tube amp. A 8-24 hour stress test greatly lowers returns on power amps.
Full power is not the normal stress test, compressed program material with peaks to clipping but averages at about average 1/3-1/2 power will generate the most heat in SS output devices. A burn-in bench pays for itself in a short time in reduced returns and increased reputation. A return has many costs, the most damaging is that customers will tell others in terms that hurt your reputation, even if the fault is entirely theirs. Proper testing and proof of performance is the biggest difference between a real professional shop and a shade-tree hobbyist who happens to have a shop. Most regions of the country have no professional shops, but lots of amateurs with store-front shops.
The surface needs to be anti-static, easy to clean, durable, hard and dense. Normally people use particle board and cover it with indoor-outdoor carpet but after a short time it looks bad, easily scratches customer units, becomes hard to clean and makes the whole shop look dirty and unprofessional.
The best and cheapest method of making a pro style bench, what I found, was the molded laminated counter top with included molded splash panel, which sells for about $3 a linear foot in lengths up to 12 feet. It is resistant to chemicals, solder burn, soldering iron accidents, and is very rigid so it is requires less massive support assemblies than 3/4 in or 1 in particle board. Cleaning is a snap, just brush it off or once a week or which there is a spill, is 409 and shop towels.
No unit touches the bench surface however, every unit is placed on a carpet sample, usually 22X16 inches which sell for $1-2 each with nicely bound sewn edges from carpet remenant or carpet showrooms. When one gets burned, toss it or use in the garage for something. The backing is tough and slides easily on the smooth(usually lightly textured) laminate surface so a heavy unit can be slid out of the way on a typical 8 foot workbench.
A matching height hard rubber AV cart allows a heavy unit to be taken from the shop lobby to the bench by the counter girls without ever having to lift it or potentially drop it. The unit would simply slide from the cart to the bench on its own carpet sample. Customers really appreciate it when their unit is cared for and is not subjected to the risks associated with conventional shop practices. Here are examples, the workbench in my spare bedroom in my apartment here in Russia and one of the AV carts. The AV carts are strong, supporting over 300 lbs and are very useful around the shop. My old shop had dozens of them. A large mixer could be laid over two of them and still able to rotate it and single handed manipulated. A large power amp could stay on it and never be moved to the bench. One of my benches had no work surface, and was intended for having both the tool box and unit under test to stay on AV carts where they could be moved as needed to get at the best angles. They are great for weighted key keyboards. Being rubber, they are never going to scratch a customer unit. My last large shop was houses in a large R&D style modern building that had thick commercial carpet in all but the warehouse. The large wheels of the carts helped transporting equipment over the thick carpet and the carpet meant no units were damaged from accidental drops.
Other considerations about benches include access to the rear. It was not uncommon to add more test gear or remove a unit for calibration so access to the rear of the bench was a very welcome difference between my benches and those of most shops. Being freestanding, the shop can be rearranged as needed when product orientation changes or when new layouts are desired. Also, make the bench large enough to allow keeping a unit disassembled while waiting for an estimate approval while working on a second unit. Since my standard benches were 8 feet, which might be too short to have two large units in disassembled states, I build extra benches for each tech. We had 15 techs and 24 benches, but some techs worked on things that were small and self contained like DAT/DA88 format decks which did not need more space. Leaving a larger unit on an AV cart allowed it to be rolled away into a storage area, still disassembled, if it was waiting on parts. The unit rolls back to being next to the bench when the part comes in. The repair is completed without ever leaving the cart and never but one reassembly. That improves shop throughput a lot. A good work bench has duplicates of some important test gear, like a scope and signal generator and metered variac. That allows close monitoring of a unit being burned in to detect time or temperature induced intermittents while working on another unit. If you are doing a lot of amps, a dedicated burn-in rack is needed. It can be fan cooled, with cooled dummy loads, have programmable signal source, limit alarms etc. Every power amp or guitar amp should have a reasonable burn-in with re-biasing done after after burn-in if a tube amp. A 8-24 hour stress test greatly lowers returns on power amps.
Full power is not the normal stress test, compressed program material with peaks to clipping but averages at about average 1/3-1/2 power will generate the most heat in SS output devices. A burn-in bench pays for itself in a short time in reduced returns and increased reputation. A return has many costs, the most damaging is that customers will tell others in terms that hurt your reputation, even if the fault is entirely theirs. Proper testing and proof of performance is the biggest difference between a real professional shop and a shade-tree hobbyist who happens to have a shop. Most regions of the country have no professional shops, but lots of amateurs with store-front shops.
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