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PostPosted: February 27, 2018, 4:05 pm 
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Joined: December 6, 2017, 2:20 pm
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Location: San Jose, California
Hi Guys,

I got my metals! Super excite. A small detail. Square tubing has a welding seam, is there a "best" way to position it for more strength, or should I not worry about it.


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PostPosted: February 27, 2018, 4:13 pm 
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Not a silly question, but the answer is it doesn't matter.The tubing is plenty strong enough on all four sides. That said, I tried to keep the seams down and out of sight, but once the frame was painted that became moot.

Good luck and have fun!


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PostPosted: February 27, 2018, 4:33 pm 
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Location: BC, Canada. eh?
You may find that the position of the seams effects the way the tubing warps during bending somewhat, but it's not a big enough problem to worry about. Make sure you CLAMP those frame tubes down to the build table, and try to alternate sides & ends of tubes when tacking and welding. That will keep warpage to a minimum.

I was really OCD about this during my frame construction, and it helped a lot. My frame is within 1/16" or better on all its diagonals. It doesn't really make a big difference in the frame's strength, but it does make adding parts later easier if the frame is as consistent as possible from side to side, etc. (i.e., it's nice to be able to make 2 identical parts, or identical mirror-image parts, knowing in advance that they'll both fit the car precisely).

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PostPosted: February 27, 2018, 4:45 pm 
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I found it's only a potential issue if it ends up where you're trying to drill the tube for rivets. Not only is the weld seam harder material, but it's also much thicker, which can mess up rivet engagement.

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PostPosted: February 27, 2018, 5:01 pm 
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Joined: December 6, 2017, 2:20 pm
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Location: San Jose, California
Ooo. Yes. I didnt think of the rivets. That's something I can think about. But in the end I will paint it. If the strength is the same, I dont think itll be such a big deal.

Yes. I will be clamping all this stuff down. I plan to take my time building this. :)


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PostPosted: February 27, 2018, 10:47 pm 
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Location: White Rock, BC, Canada
As mentioned, make sure the weld is in the least likely spot to be drilled. Other than that, nothing to worry about.
Cheers.

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PostPosted: February 28, 2018, 2:01 am 
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I've seen an argument to orient the weld seem towards tubes that can be welded across it. So on the bottom rail the weld would face up and on the top rail the weld would face down. The additional welds across the seam could strengthen or perhaps as you guys mention now it keeps the welds away from rivet holes. I think you can rely on the tubes being welded together well. So don't worry too much.

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PostPosted: February 28, 2018, 5:19 am 
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zetec7 wrote:
You may find that the position of the seams effects the way the tubing warps during bending somewhat, but it's not a big enough problem to worry about. Make sure you CLAMP those frame tubes down to the build table, and try to alternate sides & ends of tubes when tacking and welding. That will keep warpage to a minimum.

I was really OCD about this during my frame construction, and it helped a lot. My frame is within 1/16" or better on all its diagonals. It doesn't really make a big difference in the frame's strength, but it does make adding parts later easier if the frame is as consistent as possible from side to side, etc. (i.e., it's nice to be able to make 2 identical parts, or identical mirror-image parts, knowing in advance that they'll both fit the car precisely).

I'll add this to Zetec7's comments, don't remove the clamps until the welds have cooled to room temperature. Rushing here will cause no end of headaches down the line.

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