This is a post about a play set I made for my (then) 3 year old son. He loves construction trucks and playing in the sand and dirt. I looked around for construction-site themed play sets but I really couldn't find anything available. There are lots of figures and truck sets but nothing that consisted of an entire play set. So I figured I am a crafty guy...perhaps I could make one?
The idea came when my wife would typically set out a baking pan full of rice, flour, peas, noodles or other food items for my son to "run his trucks through". Obviously this proved to be quite a mess. So I thought why not make something contained, movable and at the appropriate height for him to use in a more permanent way. And as an added bonus, keep the house clean!
So I'll begin making some posts describing my journey (over the coarse of a year!) to make this play set. But for now, here is a photo of the finished project.It was a lot of fun to make. If your interested I'll be making additional posts about how I put this crazy thing together.
Play Set Construction
Making the Play Set Box
The first step required making a box. The play set portion (or insert as I call it) consists of a box filled with pink insulating foam and covered with a urethane resin creating a hard outer shell.
mache product called Mu-Cla. It takes a while to harden but is very easy to "mush" into place and soften some of the edges. Mu-Cla is a product used frequently to form rock surfaces and terrain. I wanted to experiment with this product for a while so I decided this might be a good time to use it. So I tried it out. I worked out pretty good. The picture on the left looks like a mess but with enough imagination you can kind of see where this is going.
So this is all fine and good, but it's still foam and paper mache in a box. Big deal. Any kid would tear it apart in 5 seconds flat. Plus it doesn't look very good. So this is where the Polyurethane Resin comes in.
Making the Terrain and Rocks
As mentioned earlier the Alumilite Corporation make a very cool (well, actually very HOT) 2-part resin called "Skin Coat - Rigid". You simply mix Part A and B equally and you have about a minute or so to spread it on. Its probably not the best thing to do, but I just wore latex gloves and just smeared it on everywhere. Be careful though. The stuff gets pretty hot due to the exothermic reaction caused by the two parts combining. But it was kind of fun to just make a mess of it all.
You'll also notice from the photo's a bunch of rock castings. To make the castings I once again used another Alumilite product call "2-part Liquid Plastic". This stuff is what you'll find in most hobby stores. The rock molds I used are from Woodland Scenics. I just mixed and poured in the 2-part Liquid Casting Plastic into the molds and waited. A few minutes later I had perfect rock castings. This liquid plastic stuff is excellent for making reproductions of just about anything.
Now back to the terrain. As you can see from the photos, you just mix the 2-part Urethane and spread it everywhere you can until the entire thing is covered. I had to do this in about 4-5 passes since I couldn't spread as much as I could make in one batch. But that's not a problem. It sets up pretty quick. I think I used two bottles of the stuff all together. While I was spreading the Urethane I also embedded the rock castings randomly wherever they seemed to fit. I just kind of took the castings I had an pressed them into the Urethane where ever I could.
Polyurethane before it had a chance to set. This gave a permanent impression of big construction truck crawler tracks which looked cool. I also occasionally sprinkled small amounts of play-sand into the 'wet' Polyurethane before it set. This gave the terrain a rough, gravel type texture. This is similar to what Model Railroad folks do to make terrain textures. A common technique is to sprinkle ground foam onto wet paint for the same effect.
Finally to kind of smooth the transitions between the rock castings and the terrain I filled in the gaps with Tile Grout. Probably overkill but it was easy to work with and left a real gritty texture on the surface so I think it worked out pretty well. Again I just simply scooped out the Tile Grout and applied in around the rock castings making a point to cover any gaps. Wearing latex gloves I just smoothed and pushed the ground all around the edges as shown in the photo on the right. After the group was applied and obviously the Urethane too, I noticed a lot of brittle sharp edges throughout the landscape. These obviously would cause problems with a small child's fingers getting caught on them and possibly cutting themselves. So I took my Dremel tool with a right angle attachment and small sanding drum and went around the entire play set and ground down those edges. This further helped to blend in the rocks and base together.
Finishing and Weathering The Play SetOK, now with everything covered with urethane, rocks added, gaps filled with tile grout and everything filed down smooth it was ready to paint. I wanted to first give the entire play set a base of tan or brown to represent the color one might see at a typical construction site. So I first washed the play set very well with warm water and soap. Then I spray painted the entire play set with automobile primer. After the primer I painted the play set with Rustoleum American Accents Satin Soft Wheat spray paint. Once the final coat of spray paint was applied the play set was really starting to look very realistic.
Once the entire set of painted I felt it looked pretty good, but it could use some accents or highlights to emphasize the rocks and some weathering one might see. The mono-tone color of the play set just didn't seem to make the terrain stick out very much. So I borrow some techniques from doing Model Railroad scenery and began highlighting the rocks. I painted a light grey color on the surface of all exposed rock outcroppings. I also added some burnt umber and some subtle shades of various brown, tan and red acrylic pains I had lying around. I really didn't have much rhyme or reason to what I was doing. Just kind of used a thick brush, dabbed it in what ever color looked good and stippled it onto the play set surface. Kind of half dry brush technique and stippling. Once that was dry I then high lighted (dry-brushed) the rock surfaces with a white paint. This gave the rock's raised surfaces some depth and helped them stand out from the rest of the surface. Finally I dabbed a small foam brush in a diluted India Ink wash (combination of India Ink and Isopropyl Alcohol) and just coated the whole thing in the stuff. I allowed the wash to run down groves as rest in the valleys. This create a muted effect allowing the colors to blend better and look a bit weathered. It was nice how the wash also settled into the crawler track impressions I made earlier really making the entire play set look dirty, grimy and grungy. Just like it should! Below is a photo of the final result.
The play set insert itself was certainly the most difficult and complex part of the project. However with that done, it was clear I now needed something to put the play set in. Just having the play set box lying on the floor was OK, but something like a table or platform it could sit on or in would be much better. It would need to be an appropriate height for a 3 year old however and also be kind of fun.
With that in mind I decided to build a movable wheeled car in the basic shape of a construction truck. Inside the truck then would be the play set. My vision was to have it look something like a wooden railway train table or how some of the novelty kids beds look (something like those race car beds we see for kids). So the idea developed into a simple construction vehicle with enough room inside to place the play set at a typical child's "play level".
The construction of the cart was done in two parts. One part was the bottom frame which would hold the axles for wheels and provide the basis for a strong sturdy frame to build around. This part was mainly painted in black. The second part was the upper vehicle shell which was mainly in place to contain the play set and give the cosmetic appearance of a typical construction vehicle. This part is mainly painted in yellow. So all together the entire construction site play set consists of 3 major parts; The bottom frame (black), sandwiched on top by the top vehicle shell (yellow) and of coarse the play set insert which would see all the action.
Constructing the Bottom Frame
Next I added 1x4 reinforcements across the 24" width for support in the middle of the frame. These were spaced out inside the frame to actually serve as the axle mounts which would come next. Note it was important to recess the cross supports underneath the frame to eventually accommodate the 2x4 axles. Once the basic frame was put together it was primed with regular latex primer.
Wheels and Axles
The cart obviously needed wheels. I searched around for suitable "truck" wheels which would look realistic but searching for them proved to be quite a challenge. Finally I found a huge lot of 10" diameter tires with hubs and bearings at Harbor Freight. The hubs were white, so I removed the tires and separately spray painted the hubs an obnoxious bright yellow. When they dried I reassembled them and re-inflated the tires.
The bearing hole in the hub was 5/8" in diameter so I purchased a length of 5/8" CRS rod from the local hardware store and cut those axles to length and ground down the edges. I decided to just have each axle run the width of the cart. It seemed a bit easier to construct this way and would also prove to be more sturdy in design even though it turned out to be quite expensive. To hold the axles in place, I cut two 2 x 4's and dadoed a 5/8" grove down the center of them to snugly hold the axles in place. I used mending plates (2 on each axle) to hold the axle in place after they were inserted. I also carefully drilled a hole at the end of each axle to accommodate a cotter pin which would hold the wheel itself onto the axle.
Axle rods installed into painted axle mounts. Axle rods held in place by common steel mending plates.
Constructing The Vehicle Top
Up next was the top part of the vehicle. This would be constructed like a cap that would be placed over the bottom frame. The bottom frame was intended to sit inside the underside of the top piece. The top consisted of yet another frame the thickness of the plywood larger than the play set perimeter. This added a nominal 1-1/2" to both sides but to make sure I could insert and remove the play set easily I added another 1/8" for wiggle room. So the entire outside perimeter of the top is 37-1/2" x 25-1/2".
Before assembling the side panels, I also cut what might be wheel wells into the longer side panels. The wheel wells are the sort of trapezoidal patterns cut in the panel (2 on each side). I also cut a similar pattern on the two shorter panels just to make the shape of the top a little more interesting. Kind of loosely modeling the lines of a construction vehicle. Lastly I also drilled 1/4" holes with 1/2" countersinks to accommodate some black anodized 1/4" x 20 bolts and washers which would be used to fasten the top to the bottom frame. It also served as a nice embellishment from the outside giving it kind of a tough look having some black bold heads visible around the bottom of the side panels.
Painting and Finishing the Wheeled Cart
Assembling and Decorating the Vehicle
grill and applied it. Lastly I had two vinyl lettering signs made up using this Army font I found. I sized it appropriately so that "Sam's Construction Company" could be displayed on each side. After the decals were applied it was ready to go.
My son has spent many hours playing with his "construction site" and always seems to be a popular hit whenever his friends come over to play. You may have also noticed a sand-like substance inside the play set. This is actually Moon Sand which is an awesome product. It clumps and allows kids to make things with it and never dries out. There is a 1 lb bag of the stuff in the play set you see here. A perfect touch for any construction site.