water sealing aluminum?

[meticoeus]

How would you go about making an aluminum joint water tight without welding it? Are there any common sealants or somethings along those lines?

[GT40_GearHead]

is the joint threaded, couse if it is you could use teflon tape

[meticoeus]

no, joining two plates at a non-90 degree angle. I think welding is probably the only way to go here but thought I'd ask in case someone knew of less expensive route.

[Guttenaffe]

You can braze aluminum together by using an Aluminum solder like the sold on TV infomercials Durafix ( http://www.durafix.com ) and it will be water tight.

This method is not as strong as pure welding, as it become brittle directly above and below and the joint, yet the joint's intermatalic is stronger thus their claim in true yet false. When the alum mixes with the solder metal and creates an alloy that is stronger than the original Aluminum but where the alloy bonds to the aluminum is weaker (confusing huh?)

I think this will fit the needs of case-modding...

It is easy to work with because all you need is a butane / propane torch. Or maybe REEEEAAALLLLLLLYYYYYY hot breath. :p

*note* I cannot support directly the Durafix product nor do I recommend this product over other similar products.

[CanaBalistic]

You could also use some JB Weld. Its a putty that hardens like a rock and bonds most types of metal.

Another thing would be gas tank filler putty, it's kind of like the JB weld and should be water tight.

One thing i have to mention if your not going to weld the piece together is to attach some brackets to the pieces. I wouldnt rely on any putty to be the sole support for anything. Got an old Mecano set handy? :)

Personaly, i would take the whole thing to a shop that does tig welding and get them to zap it together. It shouldnt cost very much. (ie, a cold case of beer in hand would probly sufice)

[meticoeus]

Thanks guys. I don't have an old erector set or anything like that handy (I move too much and things get lost :() But I'm not leaving anything to chance and will fasting all of my joints. I'm might look for a set though, the small pieces might be handy somewhere.

[crazybillybob]

How Thick Are the Plates? If there thick enough you can Drill a hole at the end of the Outside plates and a matching hole in the end (thickness) then tap that hole, The Plates would be held together by the screws. Then to make the joint water tight pick up a tube of RTV silicone (local Auto parts store will have it), It comes in to colors red (High temp -65degrees F to 600degrees F) and Blue (low temp -75degrees F to 500DegreesF) As long as this is a PC I'd get the blue (there are other colors/types from black to copper each has diffrent Temp rating, blue and red are just ultra common). Spread an light even film of RTV into the join Then insert and Tighten the screws. To make sure it's water tight you may want to put a bit of RTV in the hole that the screwgoes through as well as under the head of the screw.

If the plates are too thin to screw together and not going to be structural (hold up weight) you can use the RTV to "Glue" them together. I'd take some blue painters tape and use it to hold the two sides together then put a bead of RTV on the inside of the Joint. Now use your finger to press the RTV into the corner, you want a nice smooth concave bead (for an example look at the caulking around the edges of your tube or sink back splash, there made the same way). If the plates are for making a box You'll have to think through the assembaly so you can glue all the sides on from the inside (or glue the top and sides on from the inside, then glue the bottom in from the outside...or what ever, you just want the part that gets glued from the outside to be hidden)..

Good Luck, and I hope this helps get you thinking !!!

CrazyBillyBob

Friendly Neighborhood Redneck

[Malatory]

If the Aluminum is to thin to do the above. You can also get some of the right angle edging and follow the same steps the Hill billy gave above.

[meticoeus]

The thickness isn't set yet, but how thick should they be if I'm to drill holes into ends and how far apart should the screws be if the thing is structurally significant?

I'm considering making the top-bottom wing bits in my current mod into closed reservior-radiators. It seems better than the other idea I'm toying with, but I want to avoid having anything professionally welded if at all possible. B/c of the odd angle and holding lots of liquid, the whole thing will have to quite structurally sound so the plates will be as thick as they need to be.

If I can find someonethat can weld it all together cheaply, I'll almost definitely go that route.

[Malatory]

if you go with 6-32 screws you would need at least 1/4" thick.

smallest tape set I have is for 2-56. but I have not used it.

[meticoeus]

If I use this method, I'll be using either 1/4" or 3/8" but for now I'm holding off on a decision until I get back to school. Thanks guys.

[Maz]

spray your aluminum with rubbing alcohol or another drig store kind. wipe it off once then let it dry.

one pass with silicone caulk will hold it but caution

it is flexible.

[meticoeus]

Well I'm asking about the wings for my current mod. I've got to redo them from scartch as they were originally done when I was still completely new to sketchup and the original has proven useless for CAD purposes. Anyway, I'm completely torn about what to do here so I'm asking you guys.

If I'm going to drill into the side of an aluminum plate, should I go with 1/4" thickness or with 3/8" thickness? There are pros and cons for both so what do you guys think. I can fully go either way here, but I can't finish the design until this issue is settled and I'm using these purely to get measurements, so if it isn't what is going to be used I'm wasting my time.

In case anyone cares, it looks like I'll be using extruded Aluminum 6061-T6 flatbar or plate.