rear triangle
- Thread starter jj256
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Maybe this will help. To get a good strong weld , you need good fitment.
I think the problem your having is not with the strength of the tubing your
using , more the way your trying to put it together.
This is good fitment. Its called fishmouthing the tubing. You pick your angle and then
make the tube fit exactly to the tube your welding it too. Once welded the two tubes
become one and the strength of the weld is greater than the actual tubing itself.
This is just stick one tube next to another. Still a good welder can do a pretty good job
and it will be fairly strong.
This is wrong. You can't touch one end and then glob 2 pounds of weld on that end and
expect it to hold anything. Even filling up the void with a bunch of weld will still make
a weak weld. You can't build tubing out of welder wire. Hope this helps.
I think the problem your having is not with the strength of the tubing your
using , more the way your trying to put it together.
This is good fitment. Its called fishmouthing the tubing. You pick your angle and then
make the tube fit exactly to the tube your welding it too. Once welded the two tubes
become one and the strength of the weld is greater than the actual tubing itself.
This is just stick one tube next to another. Still a good welder can do a pretty good job
and it will be fairly strong.
This is wrong. You can't touch one end and then glob 2 pounds of weld on that end and
expect it to hold anything. Even filling up the void with a bunch of weld will still make
a weak weld. You can't build tubing out of welder wire. Hope this helps.
I saw a video where a hole saw was used to make the cut in the tube ends. The tube was held in a jig to get the correct angle needed and then the hole saw in the mill (drill press would also work) was brought down to cut the tube by running the one edge of the hole saw through the end of the tube.jj256 said:
i second the opinions of Luke and draco. Hole saw and a 4 1/2" grinder, a 1/2 round file will be sufficient for making just a few fittings. Take your time and do it right. And finally, yes use a jig for putting the pieces together it can be as simple as a couple of pieces of plywood for the sides and another pieces for the bottom in the center of the plywood would be an axle that is level with the bottom piece of plywood and perpendicular with the side pieces of plywood. Than just make sure that all clearances on one side are on the other. That all of the fishmouth cuts look like what Luke showed in his pics... When all the clearances are good all the joints are tight, Than weld your pieces not before.
Take your time and do it right and it will last, and work as expected, build it quick and cheaply and you could seriously hurt yourself or in the least have to build it all over again...
Rich
Take your time and do it right and it will last, and work as expected, build it quick and cheaply and you could seriously hurt yourself or in the least have to build it all over again...
Rich
Yep tubing notchers are $45 at Harbor Freight . Then another $7 for the hole saw to make them
work. You can do a pretty good job with a 4'' grinder and a flap disk . A file will also do them.
work. You can do a pretty good job with a 4'' grinder and a flap disk . A file will also do them.
