$100 DIY SLING FRAME

The goal in designing this sling frame was to come up with something that would be pretty easy to build, be able to be assembled and taken apart quickly, be very sturdy and inexpensive. This is the result, put together for around $100 in materials:

It's sized to match the Porta-Sling frame, four feet wide, 5 feet deep and six feet high, but the dimensions aren't critical and adjustments can be easily made as desired. It takes little skill and few tools to make. It's best if you have access to either a router, a radial arm saw or a table saw, but with an adjustment of materials a version can be build with a hand saw, a drill and a wrench (more about this at the end).

MATERIALS

8 - Pole Base Flanges. These are the only parts you probably can't find at a home center, but are available at Harbor Freight Tools
12 - 5/16" x 1-1/2" Lag Bolts
4 - 1/4" x 3" Eye Bolts
4 - 1/4" Fender Washers
4 - 1/4" Nuts
4 - 1" x 72" Unthreaded Black Iron Pipe (Outside diameter is 1-1/4")
4 - 2x4s
Paint (optional)

CONSTRUCTION

The only pieces that have to be fabricated are the four wooden pieces. They are made from cheap 2x4s and it's worth the few extra cents each to get kiln dried lumber. Although they're not really structural, take some time and select boards that have fairly straight grain, few knots and don't have any warp in them.

Cut each of the four 2x4s to 6'5" in length. Each pair, top and bottom, cross at about a 104 angle. Use a protractor to lay out the angle in the center of each board and mark the edges where you need to cut the half lap joint that allows them to cross. I used a router with a straight cutting bit because after marking the cuts I could clamp all four boards togetter, offset slightly from each other, and plough out the necessary material. You could also use a dado blade in a radial arm saw or a table saw or even chisel out the areas by hand. The resultant cut should be 3-1/2" wide and 3/4" deep (but measure just in case the lumber you bought is slightly off from the standard).

Here's the joint and how the two boards cross:


Once you have these pieces made, place the pipe flanges on the ends and mark the places the lag screws will go. You'll need to pre-drill holes for these so that you don't split the wood. Drill about 1-1/4" deep, taking care not to drill through the other side (although if you did it would still work just fine, it just wouldn't look as nice). For the top cross pieces the inner lag bolt is replaced by the eye bolt and these holes will need to go all the way through. Secure the flanges with the lag bolts on the bottom and lag bolts in the outer holes in the top and the other the eye bolt fastened with a fender washer and a nut on the top side:


ASSEMBLY

The sling frame can be put together by one person in less than five minutes and taken back apart just as easily and quickly.

Lay the two bottom boards down, crossed. Insert a piece of pipe in each of the four flanges. Add the top pieces (either one at a time or both already crossed. With an allen wrench, tighten the set screws in each flange. If things seem unsteady when setting it up, stand where the bottom boards cross to stabilize things as you put the pipes in place.

Now just add the chains and sling and you're ready to play. Note that since the sling itself is hung from the eye bolts that run through the flanges, all the weight and force exerted on the frame is confined to the pipes and that the wood members are simply holding the flanges in place. Because each joint is tightened down with set screws there isn't the overall play in the joints and this frame is much more solid than the portable ones. It doesn't break down as small as the commercial frames, but it is easy to store in a closet, under a bed or behind the sofa.

THE SLING

Any good four-point sling will work here. I found some on Ebay and the one pictured here was made in Argentina. You can get one shipped to the US for about $150. The quality is quite good and it comes with a pillow and stirrups. The downside to buying this is the shipping time from Argentina runs around six weeks or so, but the savings are worth the wait.

AFTERTHOUGHTS

I happy with the final product, but would make a few changes if I build another one. First of all I would rip the 2x4s to the same width as the flanges. The slight extra width there now isn't necessary and it gets in the way of the Allen wrench a bit. I also would consider shortening the eye bolt so that it doesn't stick out the top side and I'd counter sink a hole for the nut. I left it long so that it wouldn't loosen up without being noticed, but since I'm not going to be leaving it assembled between play sessions I would just have to look at the eye part when attaching the chains to make sure it wasn't coming out. I've also bought a cheap mirror (the kind for hanging on the back of a door), but haven't yet come up with a simple way to build a holder for it into the frame. At the moment I just attach it with a clamps, but that's not an elegant solution. I'll probably add a paper towel holder to the underside of one of the top cross pieces.

ALTERNATIVE METHOD FOR MAKING THE HALF LAP JOINTS

Since the wooden members aren't structural they don't have to be made out of a single 2x4. Instead we can layer two 1x4s together to make the same thickness. For each cross member you'll need to cut one 1x4 board in half at the 104 angle. Lay this on top on another 1x4 board with a 3-1/2" gap in the middle. Spread yellow caarenter's glue evenly along one of the mating surfaces and clamp them in place. If you don't have access to clamps you can put 1-1/4" screws into both pieces, spacing them several inches apart. After the glue sets up, trim the boards to length and continue as above.

FAQ

How much weight can it hold? I don't know, but the assembled stand is very sturdy. I've had a 230lb pig in mine with absolutely no indication of any problems.
How much does it weigh? As built here, 75lbs. It bundles up into a package six feet long, so between the size and weight of the pieces it isn't something you would want to cart around very often, but it's fine for putting up in your house and then stashing away once you're done playing.
Does it have a lot of "swing" in it? Becasue each vertical pole is secured in the fittings top and bottom by two screws, t's rock solid when assembled. There is virtually no play in the frame, unlike the commercial ones that simply slip together.
Doesn't the "X" crossing get in the way? No. The center of the cross is where the middle of the sling is, so you can't stand there if you wanted to. Front, back and both sides are completely open in this configuration.

COPYRIGHT

2008. All rights reserved. Permission is granted to reproduce and distribute these plans provided that this notice remains intact and no charge is made for them.