Re: Alternatives to Welding?
 

Alternatively, you can use the joints found here: http://www.brunnerent.com/Tools/Port...d/itemlist.asp, but I can't vouch for them (I've only heard of them; our team has never actually used them).

Re: Alternatives to Welding?
 

Would those bend a lot easier than gussets?

Re: Alternatives to Welding?
 

He is of course referring to the "Tubing connectors" shown on that page.

These connectors may be weaker than gusset plates; they will most certainly be heavier. If you used these connectors AND gusset plates, the joints will be nearly indestructible.

Re: Alternatives to Welding?
 

If your main concern with 8020 is the weight, just keep in mind that 8020 is pretty ridiculously as a cross member shape. Also, avoid using brackets if at all possible. Take advantage of end fasteners and anchor fasteners to save weight. Over the past few years of dealing with 8020 I have found that unlike a tubular chassis you need very little cross support to have a sturdy frame, pretty much an outer box is strong enough to hold.

If you have any more questions about lighter 8020 construction techniques feel free to respond/PM/IM etc.

Re: Alternatives to Welding?
 

If I were going to braze Aluminum, I'd probably go with something like Harris Cor-Al rather than stuff like muggyweld. This is an Aluminum/Magnesium/Silicon alloy, not full of Zinc.

http://www.harrisproductsgroup.com/e...um/Cor-Al.aspx

Re: Alternatives to Welding?
 

222 has used the 80/20 quick frame and connectors. Typically we would use gussets along with the corner connector in high stress areas. We have never had a quick frame connector fail on us.

Re: Alternatives to Welding?
 

Good old 1" square, 1/8" wall Aluminum extruded tubing is cheap and durable. Welded or put together with gusset plates and either rivets or #10 cap screws, it's workable.

Re: Alternatives to Welding?
 

The Lotus Elise uses a glued and riveted aluminum extrusion chassis. I don't understand why more teams don't do this kind of work.

Read this for more details:

http://www.sandsmuseum.com/cars/elis...al/asauto.html

Re: Alternatives to Welding?
 

971 works in sheet metal primarily, but I know they've also glued joints in the past. I know it was done on their champion 2009 robot.

Re: Alternatives to Welding?
 

125 has used a box beam/gusset/rivet setup for the past 3 or 4 years on our manipulator frames.

It makes for a very rugged connection that can be removed if necessary, while also keeping a very square frame which is extremely important to us. The frame also is extremely light which is obviously important as well. We have the ability to weld, and will do so in critical areas, but the rivet/gusset system has worked great for us so far.

-Brando

Re: Alternatives to Welding?
 

We welded for the first time this year and loved the light, RIGID result. We welded what we knew would be on the robot in week 2, and used gussets and rivets for later additions. These held up just fine.

Re: Alternatives to Welding?
 

We welded for the 2010 season. What we didn't discover until after the competition was that the welding had twisted the AL frame enough so that the wheels weren't riding evenly. We had clues before the competition, but we didn't catch them. To fix we ended up putting spacers in to make the wheels ride evenly, then we had a lot better performance.

Our students did the AL welding. Having an experienced AL welder probably would have prevented our problems, but then our students wouldn't have learned.

Re: Alternatives to Welding?
 

I have to ask, why use tubing at all? Check out my team's (1501) building method. The best thing we ever did was to embrace monocoque construction. We use 0.040" thick pre-painted aluminum sheets for 90% of our structures and I believe our bots have shown their strengths over the past few years. Monocoque structures can be built with simple hand tools and even rookie students can be making usable parts with minimal training. We have embraced it, it has done us well, it looks good and you don't have to wait for the paint to dry!

Re: Alternatives to Welding?
 

Reported.