Sorry, forgot to come back here and post my end result!
Here are some photos (off the boat):
https://www.flickr.com/photos/81273000@ ... 328939361/ https://www.flickr.com/photos/81273000@ ... 328939361/https://www.flickr.com/photos/81273000@ ... 328939361/https://www.flickr.com/photos/81273000@ ... 328939361/Design goals:
- use water safe materials that need no maintenance
- allow the hakas to stay attached while the amas are folded or extended; this was critical for me and I'm glad to say it works well!
Construction Details:
- using .100 aluminum sheet, 20"W x 84"L (~$300 for both)
- a local fab shop bent the edges over so that the seat area is 12"W, the side areas are ~2"D, and the lip underneath is ~1"W (~$100)
- then a different welding shop welded 2" x 1/4" aluminum plates for the mounting brackets. The brackets need to be 57" center to center to match the amas and I left ~24" rear overhang (from the center of the rear bracket)
- I also had the welding shop weld an "upside down" 2x2" angle iron on the bottoms of the hakas, but have since ground it off and removed it. The angle iron added more than 3lbs to each haka and they are more than strong enough as is (total welding ~$100 but would be less than half to just do the cross braces)
- I mounted 2" Stage Light clamps on each cross brace for a quick connect -
https://www.amazon.ca/dp/B0CSW5X7LS?ref ... in_title_4 (needs better ones, see below)
- I also mounted a Quick Fist clamp on each cross brace as well; size 1"-2" for the second support on each cross brace -
https://www.amazon.com/dp/B000CQPANY?re ... in_title_1 - I rounded the front corners with a jig saw and smoothed with a file
- I drilled a few 1" holes down the side; will likely drill more
- added EVA traction grip on the seat surfaces
- didn't keep real accurate total, as had to buy some extras that ended up not working; my guess is ~$600 CAD total??
Learnings:
- end result is amas that weigh ~16lbs each and I think they could be made lighter
- the key in the bend is that it is 2 bends; the first to create the sides, then a second one folded under (makes a C bend not just an L)
- .100 aluminum is overkill with the C bends; I would use .080 aluminum sheet next time
- 12" wide seats are overkill and actually I think they get in the way a bit when folded; I would likely go with 8" wide seats
- I would keep the 2" sides, but see if the fab shop could roll over less then 1" on the bottom bend; the strength is in the bend not the size of the lip (this may not be possible as it will depend on their tools)
- The current hakas are so sturdy you can jump on them on boards on the ground and they hardly flex; I will likely keep drilling more holes on the sides and likely a few along the seat area to lighten further
- the 2" Stage Light Clamps that I used are too loose and all attempts to add rubber materials have not secured it well enough. When floats extended, the combo with the Quick Fists works perfectly, but when folded the clamps are the only thing holding onto the ama's and they want to sag outward. I will experiment with other stage light clamps that may be more adjustable and grip tighter - looking at these but would need testing -
https://www.amazon.com/Clamp-Hook-Capac ... hdGY&psc=1 I will change out the clamps, but will keep the rest as is for now. Next year I may have a lighter set made.
Have a look and let me know if you have any questions; it was a fun project and definitely worth it!
Brad