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Tube Cage Question

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Folks:

I am building an Aikido preamp in an all-metal enclosure. The tubes will stick out from the top cover and I was thinking about adding a tube cage around each of the tubes. In my mind's eye, I am imagining 3 or 4 donut-shaped disks (polished copper or stainless steel, perhaps), stacked on top of each other, separated by similarly-colored standoffs (3 or 4 columns per tube cage). The top of this tube cage design could be another disk, preferably stamped so that it creates a "hat" rising just above the tube.

I can't tell how well this description reads. If it makes no sense to you, bear with me anyway: can anyone point me in the direction of attractive cages for individual tubes?

Many thanks,
Scott
 
I think I have seen what you have in mind on some gear from overseas. I don't know if anything would be available for purchase on a small scale but it would sure be worth looking into if that is what you want. One could also build something along this line with some standoffs and aluminum hollow bar stock cut to the correct size.
 
By the tone of your post it sounds like you are looking for something fancy and attractive. Just in case you are not, you could maybe look for some of those wire cages put around bare light bulbs for protection and cut them down.

If I were making them for myself I would probably buy some large fender washers at the HW store and bore out the centers to a larger diameter. This would save a lot of time and effort.
 
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Joined 2004
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Folks:

I'm imagining something that is well finished and a little exotic looking. It's true, I could probably assemble something using large fender washers and standoffs (with holes of 7/8" and 1+1/8" diameter, we're talking really large washers here), but the finish on those parts will probably disappoint me. I'm guessing that the fee that someone would charge me to refinish the parts would be crazy high, and it most likely still wouldn't meet my expectations.

Anyone else have a suggestion?

Thanks,
Scott
 
If you stick with aluminum parts you can achieve a desirable finish by yourself. If you keep tool marks to a minimum simply polishing with 000 steel wool will achieve a bright finish. Fender washers and standoffs won't cut it though for what you are looking for. You need to take a walk though a couple of HW stores and through the McMaster-Carr catalog.
 
How about purchasing a piece of copper (or aluminum) sheet and using a drill press with a hole saw of the proper size to cut the disks? You can enlarge the center hole with an appropriately sized step bit (7/8 should do it I think).

A simple jig for the drill press made of a board with dowel or plug to center the disk and a hole in which a pin or nail could be inserted to index the disk would allow you to drill three perfectly evenly spaced holes in the disks for your standoffs.

As an alternative to standoffs a 4/32 or 6/32 machine screw could be used. Purchase the screws the length you need or get them longer and cut them down if you can't find the exact length. Get some copper or aluminum tubing just large enough in diameter to slip the screw into (any hardware or hobby shop will have such tubing). Cut the tubing into sections equal to the spacing you want between disks. Drill the holes in the disks large enough for the screw and smaller than the tubing. Drill a hole in the chassis and insert the screws from the bottom. Put a section of tube on each, add a disk, another section of tube and so on for the number of disks you want. Cap off the screw with an acorn nut for a finished look.

Sounds like a fair amount of work but once you make a jig for drilling the holes in the disks and for cutting the tubing to exact length it would go pretty quickly. As mentioned previously some 000 steel wool or 620 grit wet/dry sandpaper will remove any scratches or tool marks.
 
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