DC Overkill

Doug Shepard

In Memorium
Messages
772
Location
Waterford, MI
I need to have removable DC downtubes for when the GaShop has a vehicle inside. So I'm telling my buddy Mr. Goldberg - "Rube, I know you can just plug some PVC into a bell end, but there's just something about not having a seal there that really bugs me". So Rube gets to work sketching something and hands it to me. Hmmmm sez I, maybe this could work. So here's the Rube Goldberg invention.

There are 4 plates mounted on the bottom of the rafters where the PVC ducts terminate. Each has a 14 ga galvanized ring, and a 1/4" rubber gasket. The plates and the mating ones on the down-tubes are recessed in so that the gasket seals up at the same point where the rare earth mags on the down-tubes contact the metal ring above.

PVC Fab16.jpgDownTube3.jpgDownTube4.jpg

This attaches lickety-split and can be moved from one duct to another in about 3 seconds. This first one will get used on the disc/belt combo, but is probably the same one I'll use for the router table but stuck on at a different location.
DownTube1.jpgDownTube2.jpg

I still have 3 more down-tubes to finish, another with a 6"-4" change but a little longer for the DP. Then 2 more mostly for the TS and BS which will stay 6". Then I'll tackle the flex hose machine/down-tube portion. Starting to see some daylight at the end of the tunnel.
 
I had the same or similar problem. I wanted the down tube to the TS removeable so I could pull my van in the shop if it was threatening hail (too tall to fit in the garage). I made my joint double as the blast gate. Hung the top portion on solid mounts, then put in some t-nuts so that the bottom half bolts up to it. unbolt, take the sliding section out, and it's apart. Even built rollers on the part that sits on the floor! Tilt and roll away. Now there is so much junk in the way, the storm would be over before I could get the van inside! :rolleyes:
I like your fix. Tell Rube he dun good! Jim.
 
... Tell Rube he dun good! Jim.

He'll appreciate that. I was originally going to use 3 T-Nuts and fixture star type knobs to clamp the 2 plates together around the gasket. The mags were a very late afterthought. We'll see how it all works out in the long run, but so far I'm liking the idea.

Also forgot to mention what the pierced ear-lobe is for on the down tube plates. I plan on putting some hooks up high in the rafters to hang these by when not in use.
 
He'll appreciate that. I was originally going to use 3 T-Nuts and fixture star type knobs to clamp the 2 plates together around the gasket. The mags were a very late afterthought. We'll see how it all works out in the long run, but so far I'm liking the idea.

Also forgot to mention what the pierced ear-lobe is for on the down tube plates. I plan on putting some hooks up high in the rafters to hang these by when not in use.

Doug, neat setup and will probably work fine, however, if the magnets don't work out and you still want a FAST but very positive disconnect system, you could use some Aviation type fasteners, called "Zeus Fasteners", and they come in different sizes).

They are used almost exclusively on the (metal type) "engine cowlings" and even on some fiberglass/plastic engine cowlings, and on other inspection plates of many brands of private aircraft. Basically you mount half of it on one of the flanges and it has a strong spring steel wire that goes across the center of the opening and the other half mounts to the other flange and it has a screw in it that is slotted in the middle and you just press it in with the screwdriver and turn it 90* and since the slot is angled it straddles the wire in the other half and pulls the two flanges together and locks in the indented part of the slot. To remove, just push it in, then turn it 90* counterclockwise and "walaaah", it's disconnected.

You can get them from any major aircraft supply house, or for a few, even from an aircraft maintenance shop at your local airport and they can show you how they are mounted on an aircraft and show you how to install them. I would use three per flange to balance it out.

Anyhow, this is just an idea for future reference.
 
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