DIY Swing Set, Part 3: The Swing Set has SWINGS!


This is the post where Dave tells you how we attached the actual swinging part of our swing set.

Let’s be honest: if you have no immediate plans to build your own swing set (or maybe just an unusually strong interest in swing set construction), you’re not going to read this whole thing. So please feel free to scroll through quickly and look at the pretty pictures.

I’ll be back next week with a wrap up post where we tell you how much everything cost, make sure you can find all the different posts from the series in one convenient landing spot, and do some honest reflection on whether you really want to build your own swing set or not.

But for those of you who ARE here because you actually want to build a swing set, you should have all the detail you need. Maybe even more than you need. For the tower part, we referred you to View Along the Way’s plans, because we did ours pretty much the same way. For this part, we kind of went rogue on a few key points, though, so we’re laying it all out there for you.

Standard disclaimer: we’re putting these plans out there for your information only. Build a swing set at your own risk. We’re not engineers or professional swing set builders! (It actually freaks me out that you can see the beam moving a little when bigger kids swing on it, but I’m pretty sure that’s just physics and not actually a reason to worry if you want to be a human who lives in the universe. But I tend to worry. If you want a swing set not subject to the laws of nature, then this is not the one for you.)

Okay! On to Dave’s part! Take it away, Dave!

It took two months between finishing the tower and starting the swing set.  Stupid life getting in the way.  But the swings are up and everyone (especially Abe) is thrilled.

[this boy? Would swing ALL DAY if he could]

Abe in swingA-frame diagramThis was the desired end result.  I got it pretty close, but things aren’t as flush and level in real life.  I’ll refer to different parts of the above diagram in the description below.

Here is the step by step process.

1) The 10-foot 4×4 posts (B and C) need to be cut at an angle at the top to sit flush against the sides of the 4×6 (A).  I did a lot of possibly unnecessarily complicated math to compute the different angles.  The reason B and C “needed” to be cut at different angles is because the ground is at a slight slope.  For the record, a simple approximation is to evaluate arcos(8/10) (8 being the height of the 4×6 and 10 being the length of the 4×4) to get a 37 degree cut.  My excessive calculations gave me the astoundingly different measurements of 36 and 31 degrees.  Lesson Learned #1.  Swing sets probably don’t need the same level of precision as, say, NASA equipment.

2) Lay out the posts on the ground next to the tower.  I used a scrap piece of 4×4 to get the spacing right, then marked two 2×6 boards (D) with a pencil, cut out the trapezoids, and bolted them all together with 8-inch long 3/8” diameter carriage bolts.  (7-inch long would’ve been better … as it was, I cut off the excess with a Dremel.)

A-frame on ground3) Drill 6 pairs of holes along the top of the 4×6 (yellow dots on A) for the swing brackets.  I used this site ( to determine that 18 inches was good spacing for each bracket.  I bought the brackets at Sweetland Outdoor Decor for $10 (nuts, bolts, and washers not included).  The 6-inch long 3/8” diameter carriage bolts had to be countersunk for the nut to have enough thread to grip.  Maybe 7-inch long would’ve been better again…  So glad I did this on the ground instead of after the post was 8 feet high.  Thanks for the tip, Andy from!

4) This is where it is advisable to be multiple people when assembling (IKEA reference).  The 4×6 needs to be propped up by the tower railing and the A-frame.  Gretchen came up with the excellent idea of pulling it up onto the tower and resting it on opposite railings while getting the A-frame into place.  That part was pretty tricky because the 4×4 and 2×6 joints were flexible (one bolt per joint) and they kept rotating out of place.  Eventually we got it in.  Then, the whole structure needs to be moved into place so that one end is resting on the tower railing and the other is resting on the A-frame.  One adult in the tower moving the 4×6, one adult carrying one of the 4×4 posts and (in our case) two children carrying the other 4×4 post.  (The third child had the task of watching the baby child.)

5) Bolt everything together.

a) The apex of the A got a 10-inch long carriage bolt with 5/8-inch diameter.  Since the 4x4s are diagonal, the washer and nut won’t fit flush against the wood unless you square it out.  I borrowed a friend’s 1.5-inch forstner bit, but a 2-inch would have been better.  The washer was too big to fit in the 1.5-inch hole, so I just left it out.  Anyway, this bolt goes through both 4x4s and smack dab in the middle of the 4×6.  I got a little carried away with the forstner.  Ideally, the hole wouldn’t be so deep on the top.  As it was, I had to notch out the right side of the hole with a chisel so I could get my wrench in there to tighten the bolt.

chiseled out part

b) The tower side of the 4×6 is carriage bolted to two 2x4s (that match the pickets for the tower railing, cut taller to accommodate the height of the 4×6).  Those 2x4s are in turn carriage bolted to a piece of 4×4 cut to hold the weight of the 4×6.  Finally, the 4×4 is carriage bolted to the 2×6 top railing of the tower.  So many carriage bolts!

carriage bolt where beam attaches to tower dave putting in more carriage boltsThe problem with waiting two months between buying the posts (with the tower lumber) and assembling them is that they were just sitting in the driveway alternately being soaked and baked in the Georgia spring.  This caused some unfortunate twisting, especially in the 4×6, so things aren’t quite as flush in certain places as they could be … as is evident above.  So Lesson Learned #2. Hold off on buying wood until you’re ready to use it!  (Or at least store it in the basement or garage or something.)

6) Attaching the horizontal 2x6s (E) to the A frame seemed like a really easy step, but I managed to screw it up … So this is what I should have done.

a) First, grab a random son to hold some wood for you.  I guess it doesn’t have to be a son.  Have your helper hold one 2×6 board level against the A frame while you use 2-inch deck screws to hold it in place.  Repeat on the other side of the A frame with a second 2×6. Make sure the two boards line up nicely and stay that way during this part.  Remove the screws from one side with your helper holding up both boards nice and snug so they don’t slip.  (Huge clamps would work, too, but I don’t have those.)  Once the screws are removed drill the ⅜-inch hold for the carriage bolt and hammer it in.  Let your helper rest (or get a new helper) and repeat on the other side.

b) Mark the diagonals you need to cut to make it flush with the A frame.  Take out the carriage bolts, which can be a royal PITA without a hex headed bolt!  (Here’s something I learned.  Sometimes when you hammer the threaded end of a carriage bolt to take it out of wood, you can compress the threading enough to prevent nuts from screwing on.  To protect your threads, leave the nut on the bolt while hammering.)  Anyway, with the marked boards detached from the A frame, cut the diagonal lines and reattach.  Washer and nut, tighten, and boo yah!  You’re done!

My mistake was that I reversed parts a and b above, which required my helper to hold the beams in place two times (one for marking and one for attaching).  It was impossible for me to get them to line up nicely.  I think having the holes drilled first will eliminate much of this sloppiness.

/Dave’s part!

A couple of notes:

*I’ll probably talk more about this when we do a price breakdown, but that swing hardware is crazy mega super swing hardware. If you have only young kids, you probably don’t need something that hardcore. Also, there was a problem with the chain on one of the swings, so Dave picked up some hooks so it would fit better. Anyway, here’s the super hardware:

swings10I guess that was just one additional note.

A couple of pretty pictures, as promised:

swings02 swings03And here’s where you can find the other posts about the swing set:

The Tower

The Rock Climbing Wall and Ramp

The Kitchen

Don’t forget to enter the BLACK+DECKER lithium cordless drill giveaway!


DIY Swing Set, Part 3: The Swing Set has SWINGS! — 12 Comments

  1. Awesome job, kids! I keep getting questions about how we decided the angles of the beams and such, and the answer is always, “Um, we laid it out til it looked pretty good, then just went with it.” I’m going to refer future questions to your post instead. 😉

    • What?! You mean your husband didn’t insist on spending an entire evening make a separate page with all his careful swing set calculations to post on the off chance a single person ever wanted to look at it? Weird 😉

  2. What an awesome place for your boys just to romp around! It is just fantastic friend! Dave did such a great job! Wishing you a great week ahead! Nicole xo

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