Has any one made their rigging out of aluminum pipe?
If its all about weight?
I have some 1/2 od x 1/4 id that I think would work for most of it.

Good question. Is it lighter than 1/2 conduit, per ft.?

Flathead

The aluminum also bends easyier than the conduit and viberation will also cause it to crack. When aluminum is used on the bigger boats it has to be bigger dia than conduit or ss to make it strong enough. The weight ends up being more than ss.
Thanks, Chuck

I was afraid of that( the vibration thing).
Next question: I build a lot of tree stands out of 1/2 emt. To make welds easyr I made a hand press to flatten the end. This makes the pipe double thickness and doesn't burn through. I get a much better weld that way ( maybe u can see it on my duck boat build that I posted).

Now the question; is that looked at as cheating in the airboat world? It takes three times as long for me to fit the pipe if I don't flatten the ends and I have to fill a lot of burn throughs.

This may be petty but I will probably sell the boat one day.

I was afraid of that( the vibration thing).
Next question: I build a lot of tree stands out of 1/2 emt. To make welds easyr I made a hand press to flatten the end. This makes the pipe double thickness and doesn't burn through. I get a much better weld that way ( maybe u can see it on my duck boat build that I posted).

Now the question; is that looked at as cheating in the airboat world? It takes three times as long for me to fit the pipe if I don't flatten the ends and I have to fill a lot of burn throughs.

This may be petty but I will probably sell the boat one day.

Bandit,

If I'd gone the EMT way, I'd probably also "cheated" like you did. Flattening EMT, and wrapping it part way around the piece that it's joining to is pretty quick, and strong.

A potential future buyer may not notice how the joints were even done. However, he'd probably notice cracked fishmouth joints.

So I don't really consider what you're talking about "cheating". ;thumb;

Duane

I don't wrap it though. It's a straight but joint.. Flat into round. It's plenty strong on my tree stands. Laterally by itself it's not as strong as a cope joint but I'm thinking for rigging it would b ok since everything is on angles and cross braced.
If I'm wrong, please say. I'd hate for the thing to come apart.

Just want to confirm because I've never seen one built like this (flat end).

Bandit,

It seems to me that with a flat joint, you will have the same length of welding as you do on a round joint. I would guess it should be just as strong, especially if you can get an even better weld.

I have done it that way occasionally if I was short of room at certain locations. I never felt it was taking any of the strength away. I mainly do it the normal way just for the better looks. jmo

Dave

I don't wrap it though. It's a straight but joint.. Flat into round. It's plenty strong on my tree stands. Laterally by itself it's not as strong as a cope joint but I'm thinking for rigging it would b ok since everything is on angles and cross braced.
If I'm wrong, please say. I'd hate for the thing to come apart.

Just want to confirm because I've never seen one built like this (flat end).

Bandit,

MY mistake. I guess that I was thinking about the way that I built EMT tree stands in the past.

Is a fish mouthed joint harder to weld than a "flattened into round joint?" Not really. At least in my opinion.

Is fish mounting your joints hard to do? Not really. It takes a bit to learn HOW to do it, but once learned, it's fairly easy.

I can't help but think that it'd be just a "little" stronger than a flattened piece of EMT butt welded into a round piece.

The bottom line is this: Is it a securely welded joint? If so, then who cares how you got there?

Duane

What do u use to cut the fish mouth? I may b doing it the hard way.
I prefer that look, I just have a hard time with it.

I know there are better ways to do it, but I only use a chop saw to make my cuts, and a bench grinder to shape the ends to fit. Then I use a wire wheel to clean the galvanizing off before welding. It works good for me.

Dave

What do u use to cut the fish mouth? I may b doing it the hard way.
I prefer that look, I just have a hard time with it.

Bandit,

You use a die grinder, (electric or pneumatic, your choice. My compressor wasn't up to the job, so I bought an ELECTRIC die grinder) with a cylindrical carbide burr. You can buy them in different diameters, and lengths, depending on what material you're working with.

Here's a link to some... Keep in mind that there ARE others. ;garfield;

http://www.mcmaster.com/#carbide-burs/=g2f47g

Carbide burrs DO cost a good bit more than tool steel burrs, but they last a LONG time. I bought 2 of them, because I couldn't decide on which size I needed. Once I figured out what size worked best for me, that's been the only one I've used.

Cut the piece to length, (I usually measure to the CENTER of the piece I'm joining) get your angle figured out, then go at it.

Most of mine have only taken a couple of minutes to fit. But like the old adage "measure twice and cut once", this applies double. But you won't screw up much before you've got it figured out. Do like I did. Start with the LONG pieces first. Then, when you make a mistake, you can cut them off and use them for the short pieces. ;thumb;

Duane

Here's my thoughts, A round object is stronger than a flat one. When making roll bars for or competition cars we use all round tubing bent corners and butt joints when necessarily. Say you weld a round tube on a flat piece of steel that is laying on the floor, now stand on the flat steel and try to bend the tube. You would have a relatively hard time bending it or breaking it loose for the weld. Now take another piece of the same tube and flatten the end and weld it to the same flat steel, Now try to bend that one. I am sure there would be less pressure needed to push the flattened end one over. I also think keeping the original configuration of the materials in tact will help with vibration.

As already stated, take the time to clean the area to be welded by grinding off the Galvanized plating and spend some time of fitment of the two parts connection together. A better fit will weld faster with less heat. When building your cage just tack each piece as you go then come back and work little by little in each one until they are fully welded. Skip around to others allowing other to cool before going back to them. I do the same thing when I'm welding my roll cages, bumpers and other structural parts on my Cars.

Edit: To cut the "fishmouth" I just use a heavy drum sander to size on my drill press. I also use this to clean off the galv plating. If it a piece already on the boat I just use my grinder.

The thing I like about using the bench grinder is that you can hold the piece in both hands and don't need the vice. I have carbide bits and die grinders, but I never found them to be faster or have any advantage over the bench grinder, except if the thing your working with is already fastened to the boat.

Also, My vice and drill press is at one end of the shop, and the chop saw and bench grinder is at the other.;rasta; Probably poor planning on my part.

Dave