Sunday, February 27, 2011

Make Your Backyard Ball Field Look Professional

Make a Homemade Line Marking Machine
(c) 2011 by Tom King


A homemade line marking machine can be cobbled together from a pipe, some window screen and bits of plywood. A commercial line-marker isn't very expensive, but if you want to put one together for yourself, this is one way to do it.

Stuff You Are Going to Need:

  • Half sheet of half inch plywood
  • 4 round head bolts, one quarter inch by 3-1/2 inches long
  • Saber saw
  • Compass
  • Drill
  • 1 half-inch drill bit
  • 1 hole saw, ¾ inch diameter
  • Large cork
  • Stapler
  • Tin snips
  • 12 quarter inch nuts
  • 8 quarter inch lock washers
  • Screen wire, aluminum
  • 1 3/8-inch all thread rod, 5 inches long
  • 2 3/8-inch nuts
  • Metal punch
  • Mallet
  • 1 steel pipe, 3/4 inch  by 5 feet long
  • Pipe insulation
Mark two 12-inch circles on the plywood and cut them out with the saber saw. Sandwich the circles together and drill four quarter-inch holes evenly spaced an eighth inch from the outside edge and through both plywood disks.

Feed the four quarter-inch bolts through one of the disks all in the same direction. Slip lock washers and screw nuts onto the bolt on the opposite side of the disk to hold the bolt in place. Tighten the nut. Screw a second nut 3/4 from the ends of the bolts and thread lock washers over them. Place the second disk over the bolts and bolt it to the end with four more nuts. This will secure the disks about 2 inches apart.

Drill a 5/16-inch hole in the center of the two disks running all the way through both disks for the axle. Drill a ¾ inch hole in one side with the hole saw. Plug a cork, large enough to fit snugly into the filler hole.

Cut a strip of screen wide enough to cover the gap between the disks and long enough to circle the outside diameter of the disks. Lay the screen around the outside of the disk assembly and staple the edges to the disks to create a drum with screen wire edges.

Drill a 5/16-inch hole horizontally through the end of the ¾ inch pipe about half an inch from the end. Fish the 3/8-inch all thread rod through the hole and bolt one end leaving most of the length sticking out on the opposite side.

Slip the disk onto the axle with the filler hole to the outside. Screw a nut onto the end of the axle to hold the chalk drum in place on the axle. Lay the assembly on its side on a hard surface. Place the punch against one end of the axle and tap it with the mallet to expand the threads and hold the drum in place. Flip the assembly over and expand the other end of the axle.

Slip pipe insulation over the opposite end of the pipe for a handle grip and duct tape it into place. To use the marker, fill the drum with lime or marble dust and roll it along the ground to mark the lines.

Store the marker machine in a dry place with the marker dust.  Keep everything dry so that the marking dust doesn't cake on the screen when you roll out the line.  Avoid using on wet grass to prevent clumping of marking chalk

Note: When I first made one of these I lived in bone dry Texas. If you live in a damp climate, you may have to do as I did and bolt two additional circles of wood on either side of the drum. After I moved north, I found the constantly damp grass clogged my screen so that the lime/marble dust wouldn't flow. By adding disks that were 4-6 inches in diameter larger (depending on how high your grass is) to the outside of the drum, I could lift the screen a couple of inches above the grass. The white dust is neatly confined within the width of the two wheels and still make a neat line. Simply line up the bolt holes, mark the additional disks, drill them and bolt it all together with the larger disks on the outside of the drum. You may need to use a half inch or so longer bolts but it shouldn't be a problem.

© 2017 by Tom King

Thursday, February 03, 2011

Homemade Backyard Swings

(c) 2011 by Tom King

I love swings despite my checkered history with them.  When I was in elementary school and weighed not much more than a mid-sized cannonball, I took to launching myself for distance from the formidable steel and wood swingset on the Keene Public School playground. I was small then and fearless and could outdistance anybody in my classroom, even the older kids.  I was already developing theories about trajectory and experimenting with an early release strategy that propelled my skinny self out to distances that outstripped my opponents by five to ten feet.  I had discovered, just as military scientist and engineer, Niccolo Tartaglia, had  during the Rennaisance, that the optimum angle of initial takeoff was 45 degrees. Therefore if I parted company with the swing halfway to the apex of the swing's arc, I could add significant distance to my jump.

I was light and the grass in front of the swing was thick and deep, so I managed not to break anything. The swing's seats were solid wooden two by sixes, which, though capable of giving you a broken nose or concussion, were really easy to jump out of. Sadly, insurers these days require us to use those rubber, butt-hugging flexi-seats on the grounds that they won't knock children unconscious who walk in front of them. I believe this leads to children being less careful about what they walk in front of, but I do understand the safety people's concerns. 

That said, here's how to make a nice two seater swing.  Make it a little wider and give yourself about five feet of clearance between the swing and the posts and you can play a nifty game with the kids called "Cut the Butter".  (I'll describe how that's played sometime in a later post, in case you missed it growing up).

First thing you need to do is dig two holes about 15 feet apart with a post hole digger. The holes should be at least three feet deep. Site the holes so that there are no obstructions within 15 feet of the swings in all directions.  I like to have a good 20 feet in case you get a jumper...

Dig the bottom of the hole wider than the top. Do this by angling the attack of the post hole digger so that you cut out a bell shaped bottom for each hole as shown in the drawing to the left.

Insert the posts in the holes. Turn them so they are squared with one another. The posts should be six by six posts and 10 to 12 feet long or longer depending on how tall you want your swings. Buy pressure treated posts. You want this swing to last a long time and be safe for the kids to use. Always over-engineer where playground equipment is concerned.

Lift the posts and pour pea gravel around the base - about 2 inches below the bottom of the post so each sits on top of a layer of gravel and then another 4 inches around the base as shown at the left.

Mix up concrete in a wheelbarrow. Depending on how deep and wide you dug the post hole you could need two or three bags of concrete mix. The more you use, the more stable your post will be. Fill the hole to about 4 to 6 inches below ground level.

Allow the whole thing to sit for at least 24 hours for the concrete to thoroughly cure. Fill the rest of the hole with dirt and pack it down tightly.

Clamp a 2 by 8 inch pressure treated board to one side of the two support posts as shown on the right. Get a couple of large Vice Grips (TM) clamps.  You'll be so glad you have them. They are well worth buying just for this project. Another way to do it is to hold them in place with a nail on either end till you drill the bolt holes.

Clamp or nail a second 2 by 8 on the opposite side of the upright so the posts are sandwiched between the ends of cross members. The longer the 2 by 8's the more clearance you can give the swings to the sides. Kids WILL try swinging around in circles, so the more you can do to keep them from wrapping themselves around a pole the better. 

Drill 5/8 inch holes through the ends of the cross-members and the posts. Insert a ten inch long 5/8 inch carriage bolt and flat washer through the holes and bolt them in place with a flat washer, lock washer and nut.

Cut four 8 inch long pieces of six by six post. Tap them into place between the cross members and clamp or nail them in place.  You will attach the eye bolts through the blocks for the swing chains.  Each pair of blocks should be two and a half feet apart for the swings. Center the blocks for the two swings between the posts with 3 feet of clearance between them.

You can also use a three foot long 6 by 6 instead of two shorter ones. It makes it easier to place the support bolts and vertical eyes through the blocks without drilling them too close to each other. For an even sturdier solution run a 6x6 the length of the gap between the cross members. That sucker ain't goin' nowhere. Space the long carriage bolts between the vertical eye-bolts for the swing. Costs a little more with that much lumber up top, but then, peace of mind always costs a bit more!

Drill a half inch hole through the cross-members and the wooden support blocks.  Offset the holes a half inch from center to allow room for the eyebolt to pass.  Bolt the blocks in place. If you haven't nailed the block into place, drive a pair of nails through the cross-member into the post opposite the side the carriage bolt is on.

Drill a half inch hole vertically through chain support blocks. Offset the hole an inch from the carriage bolt through the chain support blocks. Push each ten inch long, half inch carriage bolt through a flat washer and through the vertical holes in the blocks and screw a half inch screw-on threaded eye bolt onto the end of the carriage bolts. 

Hang the swing assemblies on the eye bolts.  You can buy swing seats with chains at big box stores, discount houses and home improvement stores.  They come complete with chains and hooks and can be hung right out of the package.

You are ready to go.  Simply add kids.

P.S.:  I forgot to include a materials list. This bad boy will look nice and last nearly forever, but the materials can add up.  I scrounged a lot of my timbers.  I used some long scrap timbers I found from a demolition project on an old building. I got them cheap and they gave us a rustic look. I had to sand the splinters away and seal with a heavy clearcoat because it was on a children's playground, but it looked good and still saved me money.  Anyway, here's the list -


2 treated timbers, 6 by 6 inches by 12 feet
Pea gravel
5 bags concrete mix
2 treated boards, 2 by 8 by 16 feet You can use
4 pieces of treated timber, 6 by 6 inches by 8 inch or two three foot long six by sixes
1 Box 16d nails
6 Carriage bolts, 5/8 by 10 inches long
12 flat washers, 5/8
6 nuts, 5/8
4 Screw-on half inch threaded eyes with half inch carriage bolts, 10 inches long
2 Swing, chain and hook assemblies

Post hole diggers
Wheelbarrow, shovel and water hose
Circular Saw
Large Vice- Grip (tm) C-clamps
Drill and bits


When I built this thing, I over-engineered the heck out of it because it was going up on a day care center playground. That makes it more expensive, but also longer lasting and sturdier. My license rep was skeptical that I could pass safety inspection with a homemade wooden swing, but I did. I recessed all the bolt heads for added safety. You can do that with a paddle bit to avoid people catching themselves on the bolt heads, but for this swing, the bolt heads are out of reach so unless you want to do it for aesthetic purposes, it really isn't necessary. My license rep was impressed anyway.

The swing chains and seats can be purchased complete. You can get the cheap ones at Wal-Mart for not very much and just hang them when you've finished building your swing - easy peasy. If you want the heavy rubber belted industrial strength swing seats, you can order those on-line from a playground supply company and they do get pricey.  If you want to go traditional, you can cut a seat out of a 2 by 6 or 2 by 8, bolt U-bolts into the ends and hang it from chains with "S" hooks.  Just bend the U-bolts in the center to make a sharp "V" shape so the seat doesn't slip and dump the rider.

Caution: I like the wood seats, but with kids around you have to be very careful with them. Wooden seats can whack the little ones in the heads and cause concussions, lost teeth, black eyes and all manner of head trauma. I waited till mine got older before I put in a wooden seat. I went to wood mainly because their mama loves to swing and doesn't like the rubber sling seats (too constricting). I would never put wooden swing seats on a playground where kids are unsupervised or only minimally watched.

With scrounged material I spent about $100 building this one back in 1987.  With careful shopping you should be able to do it for a little more than twice that nowadays if you shop carefully.  The big cost will be the six by sixes.  You can do it with 4 by 4 uprights, but they will tend to flex more and can work themselves loose in the ground, so you'd best dig a larger base hole and put in more concrete if you use smaller timbers. I stuck with the larger timbers because my family are very large Texans and we like to swing high!

With costs for building materials skyrocketing, the best way to figure the costs for this is to carry the materials list down to Lowes and check prices. Also check old downtown building demolition projects. They sometimes tear out big old solid beams that have been cured indoors for ages. If you know someone involved in the project, they might give them to you for a good price. You can treat recycled beams yourself with outdoor wood treatment and spray on water seal. If you have time, you might want to hold off on your project a few months till you find the right wood for the project. I love aged wood anyway and for outdoor garden projects, it can really give you a stunning effect.

Hope this helps. Good luck with your project. It's worth the effort and cost, I promise.

A backyard swing is good for the soul. There have been scientific studies.


Here's a diagram for how to recess the bolts and nuts to prevent injury to the kids. Once the bolts are tight, cut off any excess even with the top of the nut or bolt head. Use a hacksaw or saws-all with a metal cutting blade to cut off the bolt. Use a file to smooth any jagged edges.

Reader Dave sent me this picture and the following description of his version of this swing.

Hi Tom,

Here's the photo of your swing set design that I built last summer.  I was going for tall, so I used 16' 6x6's for the uprights, and 16' 2x8's for the beam, with three sections of 6x6 sandwiched between.  I would like to have gotten the posts buried a foot deeper, but did the best I could with a manual post hole digger in rocky clay.  There are several hundred pounds of concrete around each base, hopefully compensating some for the depth.  (It moves a small amount while in use, but I can't decide if it's really moving at the base, or whether those uprights are actually long enough to flex a little.)  I didn't have a helper so I bolted the beam together on the ground and used a couple inexpensive block and tackle setups to raise it into position and bolt it in place.  The toughest part was digging those holes and mixing dozens of bags of cement.  I would not look forward to doing that again!

All that being said, it's just a backyard set for my kids, and unless one of those 6x6's snaps, I can't see it coming apart.  I know there are easier ways to do a swing set, but I really like the aesthetics of this one, and the kids love the long swings.  I spaced the chain hangers such that it can be set up multiple ways:  three swings with adequate clearance, two swings with massive clearance, or one big porch swing in the middle if we gear down once the kids are grown.

We hope it stands the test of time.  Thanks again for the idea.

Best regards,

Author's Note:  I expect Dave's swing will stand for a good long time. I really like the wooden caps he put on top of the uprights. Gives the swing a finished look.  - Tom

Swaying Problem:  

Jason Hoppert sent me the phone at the bottom. He used 16 foot 6x6 uprights which made for a taller swing. He used almost a thousand pounds of concrete in the bases, but when he got it all together, he found there was some sway at the top. The lower half of the uprights don't sway, but the upper half does because of the extra height. The pull of the chains on the top crossbar get extra leverage on the uprights because of the extra height.

This probably won't cause much trouble for lighter weight kids swinging, but for adults it could cause excessive wear and tear on the wood supports. You could either brace the posts with angled supports or bolt a couple of 2x6s to the front and back of each upright to strengthen it. It's totally worth it to give you the extra height. Jason did some strengthening by attaching a crossbar to a nearby tree giving him some extra support. What he needs though, is lateral bracing front and back. If he gets back with me about measures he takes to stiffen the uprights, I'll add the information here.  Meanwhile this looks kinda awesome. I love the height. Jason is also adding lights so it can be used after dark.

© 2012 by Tom King