I would like to ask you to start looking at your 2x4 cut list.
how many pieces of what length do you need (do you want to add some extra horizontal pieces like I did)
how can you assemble these pieces to make efficient use of a 10’ length of wood (or, a 140" piece, just shy of 12’, but a common size in metric countries, and not wasting a lot of a 12’ board in the US)
This is the cutlist for my alternate2 design (shortening the supports to 10"
I agree, that’s the version where I say I know it will work, the question is if the one on the left is strong enough.
But these are permanent joints, adding glue makes sure they won’t work loose over time.
lol… I was just doing that… will post soon. I have to double check… I’m at six 2x4x10 total… but need to check
I think that the left one is probably more than strong enough and should sag minimally if at all and if it was an issue a diagonal brace could be added.
A combination of the two, with the ‘left’ 2x4 attached to the beam and a copy of the ‘right’ 2x4 beneath it as a support would take little extra material and would make the beam adjustable by moving it and the ‘left’ 2x4 in or out but keeping the ‘right’ support fixed.
This is my rough draft at it. I left off the top 2x4 that tied the two legs together. I don’t think its necessary in my design.
The design uses (4) 2x4x10 and (3) 2x4x8. I hope I’m not leaving something out.
The two greens are the top and bottom beams. Oranges make up the legs, yellow make up the bottom protrusions for the stretchy string and the light blue is the top plywood edge stiffener. This is based upon a wide separation of the legs and the only thing that’s affected by the separation is the length of the plywood edge stiffener.
I want to check the dimensions of my design to make sure it makes sense. What is the angle of your frame and the vertical distance between the motors and the top of the workpiece?
This doesn’t include the top beam, bottom support, or the tension supports on the bottom support
I would add a horizontal bar across the back legs to make sure they don’t get kicked sideways
Yellow are the tension supports. Green is the top beam and bottom support.
Regarding the back legs, I was thinking about using a piece of plywood off the back extensions to provide support for sliding plywood on and off (for storage). That would tie those two legs together.
Well, mine folded so any angle 
But plan for 10-15 degrees
You need 9+ in clearance on the bottOm (more if the bricks hang down)
allow 16" from the top of the work area to the bottom of the top beam
normal doors are 80" tall, garage doors are usually 84" tall
Think if someone is not extending the crossmembers for storage
(Or add a second sheet of plywood to the build requirements)
If this didn’t have the 2x4 on top, how would that change the evaluation? (Loojing at @madgrizzle design)
One thing I don’t like about drilling through the legs is that if the holes are not right (at least parallel and the same height in both boards, even if not straight) the top beam won’t be level. Some error can be accepted (cut the bottom support to be level with the beam)
I think that lining the board supports up with a factory edge on the leg will be more reliable
@dlang, in alternate design 2, how do you brace the back legs to keep them from sliding out. I see what I assume is a pivot point at the top, but nothing between the front frame and the legs down low, to keep them from splaying out.
At this point, @dlang, my design is essentially your alternate design 3 except I put the brace between the front face and back legs at an angle and extend it some for plywood storage…
the plan was to use rope/chain to limit how far out they go (and adjust the angle)
Similar requirements, similar results 
I’m not good at onshape (runs real slow on my computer for some reason)… can you look at possibly extending your brace out about 9 to 10 inches and raise/lengthen your back legs so that there is a little over 4-feet between the brace and where the back leg touches the front frame (so as to fit a 4-foot tall sheet of plywood along the back) and see what all that does to your material list? Have you made one for alternate 3?
When my 1:15 late train arrives I’ll give it a shot. I didn’t make a list for alt 3, it was just a “quick” way to show the differences
I’m taking the train to bed…
What are the advantages and disadvantages of using a lag bolt vs using a carriage bolt with a nut on the back.
A) Which is more likely available in a big box store or hardware store?
B) One is a 1 time use fastener with a 1 time limited use range - go to far and it’s over. The other has infinite degrees off adjustment.
Thank you
