The AM Forum

My 813 rig power supply is going to weigh over 100bs so I assume that it will be built around a STEEL box.  The mod deck would also probably have to be steel though I would think the RF deck could be aluminum.  I am looking for ideas on what to buy or build.  I am guessing that most people buy the box that the components are mounted on and the fabricate sides that support the weight.  The front panel that mounts into the rack can be bought but doesn't seem like it would be that hard to fab.

The prices for sheet metal parts seem very high (bud etc) so I am open to cost saving measures.  I do want metal panels as opposed to Plexiglas.

I appreciate and words of wisdom.

Thanks

Rich

We used Bud cases. You can get them cheap and they take up little space on the floor.

Rich -

Look up scrap metal yards in your area. They sell sheet aluminum by the pound - cheap.  You can have a local shop cut it to size and then use aluminum 1"X1" angle to hold the various boxes/chassis together with 6-32 screws/nuts.

You can make your own panels out of scrap steel or alum too.

Break free of the commercial metal working limitations and save lots of $$ and have no restrictions in construction parameters.  Maybe you already have a shop full of machines for this stuff. A bandsaw and drill press is handy. A brake and sheet cutter is even better. Though, visiting a metal shop is usually a good way to go. Give them a diagram and the materials and the price is usually cheap.  They will see you know what's going on and will price it right.

T

All my big PS transformers, chokes and caps  sit in the bottom of the rack. From there they're wired to the various chassis's.

Salvaged steel panels, either from appliances (washer, dryer, etc) or shelving.  strong but Need good tools to work it.

Aluminum sheet from salvage when i can get it- easy to work but expensive if not salvaged.

Sometimes just Masonite sheets when nothing else is available - Cheap for new materails, easy to work, obviously no shielding but I have lined areas with aluminum flashing to provide some shielding in receivers.

Before WW2, hams often made rack panels of tempered masonite, then painted it black wrinkle. Outwardly, you can't tell it from real metal panels. I have been fooled a couple of times when I grabbed vintage hamfest bargains.

I keep a lookout for metal panels at flea markets, whether commercial rack panels or heavy sheet metal stock.  I have a scrap metal pile in the garage that has got me out of many a jam when building a homebrew project. I never throw away a used rack panel unless it is so full of holes I could never possibly use it.  One or two small extra holes can be filled with wilke buttons. (http://www.cessna170.org/forums/download/file.php?id=2082&sid=206291acbbc543604395c914f48abe24)

I don't have a band saw (no place to put one), but I  have been able to do a credible job making straight cuts on sheet metal using a skillsaw with a sheet metal blade, or a jigsaw with a metal cutting blade, a couple of C-clamps and a good straight piece of angle stock to use as a guide.

You need to be collecting this stuff like most of us old timers.  A 3 foot Bud cabinet would be a good housing to use, if you can find one.  I have a number of them, but there're in NJ.  Ask around, some local ham may have one they don't need.

Another good place to find stuff is a local college or university.  They usually have a salvage dept.  They pull all kinds of labortory equipment from service.  Some of the best stuff I ever picked up was from Rugters University here in NJ.  I could fill a whole van with equipment for 20-30 bucks.

Sheet metal,  like Tom said, check out a local scrap yard.  You'd be surprised what shows up in some of these salvage yards.

I would use aluminum for everything, it's much easier to work with.  You can use 1/4" plate for the heavy power supply.

Rich, one thing you may realize is that it can take longer to get the mechanical portion of the project done than it takes to do the electrical.

Fred

There is a metal fabricating place up the road a ways where I can get 4x8 sheets of aloonium rather easily. They carry several different thicknesses. They supply most of the dirt track racing fellows around here since the cars are mostly aloonium. Go to a dirt track race and make a few contacts!

Stop Signs ::)

Before you go out on a midnight run check with the towns highway dept for any that are getting tossed.

A couple of stacked pieces of 1/2" plywood will hold up any iron youre apt to use and you dont have to worry about leakage to the case. Just dont ever go near it without pulling the plug and using a shorting stick on the caps.  Lots of things can be mounted to the rack side walls, just like the BCB boys did. Use decent wire for anything carrying serious voltages. I like to use solid RG-58 or 59 with the shield removed but the jacket back on for a lot of point to point stuff

Masonite front panels are great, easier to work than 1/4" aluminum or 1/8" steel. Use L angle mounted front to rear to slide the chassis in as masonite doesnt have any strength. You can use side support brackets to mount handles to the panel so it can be pulled out to get a grip on the chassis. Many racks already have drilled and tapped holes for the L brackets; I picked up about 100 brackets back in the 70's when Sanders Associates was scrapping them, got 6 nice enclosed racks also

If the RF unit is all shielded and mounted to the chassis you can use masonite for a panel, recess the upper part of the cage a bit to fit meters in the panel.

If you need to shield the masonite go to a shop that does duct work and get some scrap pieces of galvanized sheet, there are several adhesives to bond them together. You can get aluminum from a place making gutters.

Carl