Secure Mechanical Coupling

with no picture we can only guess. FWIW there are door hinges where one side lifts off the other.

NT

You want a picture of the boards? Here is a side view...

Secured end Joint Cantilevered end ______________________ _________________ \ || \ / o || o / \ || \ UP /\ / o || o / \ || \ / o || o / DOWN \/ \______________________||_________________\

1x6 deck boards. There are two parallel boards spaced about 1.5 feet. Top view...

_____________________ __________________ Z_____________________||__________________Z | | | | | | | | | | | | | | | | | | | | _____________|_|_____ ______|_|_________ Z_____________________||__________________Z

- Add joiner(s) to provide support up/down and side to side (in and out of the page). I've considered using ordinary door hinges, one on each side of the board. I'm concerned they will be a PITA and require tools to insert/remove the pins, but if I sandwich the board with a hinge on each side they should do the job... maybe.

Is that more clear?

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Rick C

and very heavy duty gate hinge equivalents

NT

Den tirsdag den 8. august 2017 kl. 22.34.38 UTC+2 skrev rickman:

overlap the boards with a metal sleeve around them, or like an extendable ladder with two brackets one that hook over and one that hook under

or put the hinge on the topside and flip the cantilevered side back on the fixed side when you don't need it

Lasse Langwadt Christensen wrote on 8/8/2017 5:15 PM:

The hinge was my first thought, but the boards are only 1 inch wide (2.54 cm) and there really isn't enough width to fasten a hinge. I would have to create a special bracket like your metal sleeve. I'd rather buy something if it will do the job and not be overly expensive. Hmmm... come to think of it, the price is likely going to be the problem. Even the door hinges start to get expensive once they are larger than 3.5 inches and stainless.

I'm picturing something like the buckles they use on toolboxes with a loop that flips over the other half and a handle that locks it down. one or two of those on each side of the board along with a couple of alignment pins in the wood could do the job. Heck, if I got fancy and drilled a through hole in the alignment pins for a cotter to stick through they could do the whole job, but it would be a bit tricky to get the hole lined up in the board both when making and when using.

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Rick C

If you're driving around with this thing, you need a safety flag for any load that extends 4' or more from rear of truck.

You might at least mark this "Off Topic"

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Regards, 

Adrian Jansen

From where do you measure the "rear"? I'll make sure it is 3'11-7/8"

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Rick C

Did I forget to mention that it will have a red electric light on the end to alert drivers. It will be on a cord so it can be attached to the end of the load resting on the frame.

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Rick C

The bumper. Just get a cheap flag at HD, save yourself a $75 ticket and the hassle of going into court to argue it (probably to no avail in revenue conscious counties).

Well, joining boards end-to-end with a metal hinge is a poor idea (the screws that hold the hinge will be close to the board endgrain edge) unless you mount two hinges, and lap the boards. One hinge secures the top edge of two boards (overlapping by circa 6 inches), and another secures the bottom edge, and it comes apart when you pull two hinge pins.

Easier might be to sculpt the boards so that the overlapping faces have interlocking ridge/valley features (sounds hard, but with a V bit in a router, and an Incra-Jig, only takes a few minutes). The iterlocking faces can be clamped together with C clamps, or a few big washers and nuts 'n bolts. Spreading the stress over a large wood/wood contact area is safer than putting it into hinge screws (which is why hinges are carefully mortised into wood when they're holding heavy doors; you need the hinge EDGE to bear on a lot of wood surface).

There are such things as lift off hinges, so you don't have to knock stuff apart. Run search for "2-1/2" x 2-1/2" Steel Lift-Off Hinge" at

where they run about $3.

The tail gate doesn't count?

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Rick C

Exactly what I would do.

Not following this at all.

That would help take the pressure off the hinges for sure and make a standard hinge a possibility I think. I'm still concerned with the pressure on the part of the hinge that the pin passes through. There can be a *lot* of vertical force when the truck hits an unexpected bump. I think the V grooves is a great idea. I will need to get a bit for the router or use a hand saw. I'm not at all sure how I would guide the router cutting the end of a long board. They don't have to be exact cuts as long as they are well mated when the hinge pulls them together.

I would definitely need tools to take the hinge apart and put back together though as there would be pressure on the hinge pin. Using pins that go into both board would deal with all the side forces without adding any tension to the hinge, but will be very hard to make accurately.

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Rick C

This joint will have some fair amount of torque on it. In fact, as I picture this more clearly there may be too much torque for hinges to support. I'm sure a lift off hinge would be a poor choice.

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Rick C

to retain the strength of the cut board any fixture will be extend at-least twice the width of the board along its length and include reinforcing the cut against splitting. it will probably be bespoke. somehting like a ruler hinge but large.

If you want an off-the shelf solution fit a ladder rack, or roll bar, and transport the rig aloft instead of cutting it.

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This email has not been checked by half-arsed antivirus software

And you need to ask a heap of electronics design engineers how to wire up a light :-)

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Regards, 

Adrian Jansen

It's hard without a picture. Two boards, lapped by 6 inches, with torque from the load putting tension on the top edge, compression on the bottom edge. Mount hinges with one on the top edge engaging the left-leaf rotating-weight-bearing surfaces with the right-leaf weight-bearing surfaces, and insert the pin to hold those surfaces together. The pin is under no load, that tension is all on the hinge pivoting surfaces. Do the same on the bottom edge, where there's compression, and insert THAT pin as well.

The tension or compression will bear on the mortise edges of the hinges, and on the screws, which are far enough from the end of the board that they won't just split the wood apart.

It would not hurt if you said how much weight the frame needs to support.

You might look at things like crane and pickup crane at Harbor Freight.

Most cherry picker type cranes have telescoping members and fold up. But making a metal frame may be overkill if the weight is only about 200 lbs.

For things too heavy for me to pick up, I use ramps and a come-a-long.

Dan