I've built three over the years.
All three were made using 1/8" thick angle-iron and steel bar picked up from Home Depot.
1st was strictly bolt-together, as I didn't have welding capability. The next two were welded together. None of them were particularly great looking, but with a coat of black paint, they weren't altogether embarrasing either. All were over-built!
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All of them carried my briefcase / lunchbox back and forth to work with no issues.
I have a picture somewhere of that last one - I'll have to dig it out and post it.
Kirk
*edit* - here we go. A '82 Yamaha XT200 from a few years ago. Worked like a champ on my 60-mile-per-day commute. You should be able to do it, too.
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