I didn't follow the plans very closely (my bolts and dimensions were different) - I just used the general layout of the stepladder as a guide.
This was the first project I've made using a tablesaw. You could make this stepladder with a circular saw or even a handsaw, but I found the tablesaw made precision cuts really easy.
In this instructable I also describe how to use a router to make dado joints and consistent curved corners.
Step 1: Materials
You'll need a sufficient quantity of reasonable quality wood - I used about 7 planks of white pine, measuring 90 x 20 x 900 mm
8 x M8 carriage bolts, about 55 mm long
8 x M8 washers
8 x M8 lock washers
I used carriage bolts which have a large dome head, this means you only need a washer on the end with the nut.
The lock washers are needed because the bolt are inside a moving joint. Without the lock washers the nuts would gradually undo themselves.
M6 bolts would have worked fine too.
Step 2: Tools
Drill press (the bolts really need straight, 90 degree holes)
Router (not essential)
Jigsaw (not essential)
Sandpaper - I used grits 180 and 320.
Eye protection (essential)
This project uses several power tools. Respect these tools, never take shortcuts. Safety First. Remember hearing and eye protection.
Step 3: Overview
- Back support: Two sides with three joining pieces (stretchers). Joined by dowel-reinforced butt joints
- The steps: Two sides with three steps. Joined by dado joints.
- The top: Five slats with two supports. Joined by dado joints.
- Side supports: Two simple side pieces with rounded ends.
The stepladder folds up to form a compact unit for storage.
Step 4: Inital cutting
Next I ripped several boards in half. I used a piece of scrap to check that my fence was set at the right distance from the blade.
I cut the ripped pieces to length (various parts) and put an angle on the top supports (my first deviation from the plan).
Step 5: Top Piece
I used a router to cut these dados.
I didn't line up the slats perfectly with each other while I cut the joints (oops), so after the top was glued up I used the router again to trim their ends straight and flush.
Step 6: Rounding Template
The template is made out of a scrap piece of MDF. First I cut it to the right width. Then I drew a half-circle of the right diameter on it.
I rough-cut this half-circle using my electric jigsaw, then filed it closer and closer to the line with a rasp and a file. Sandpaper gives the template a very smooth profile.
It is worth spending a bit of time at this stage to make sure the template is very accurate, since you will be using it on several parts of the project. If it is wonky, the wonkiness will be copied to all the curves on the project!
Using the template is easy. With a flush trim bit in the router, I clamped the wooden piece to the template and ran the bit around gently, then more firmly, to form the curve.
It's an easy, repeatable cut, just needs a bit of cleaning up with sandpaper due to the way the curve cuts into endgrain.
I rounded both ends of the step supports, the top of the back supports, and the side supports.
For each piece, I cut curves on one side and used that side as a template for the opposing piece - this makes sure each pair of pieces are identical.
Step 7: Steps
I cut the six dado joints in the step supports, which I cut using my router.
These are the nicest joints I have ever made, they were a very tight fit even without the glue. I like making things 'properly' - without any screws or nails - I think I will try to use more joints like these.
I cut the three steps to length and made sure they were identical. I also made sure there were no large knots in these pieces of wood. We don't want a step breaking due to weakness introduced by knots.
There was a bit of tearout at the edges of the joints, will have to try harder to avoid this in future - maybe use a bit of scrap at the edge to try and prevent this.
Step 8: Back support
I made my stretchers fit between the back supports instead, and used blind dowel joints. I think this is more attractive and it is very strong and sturdy.
I made a simple jig with a piece of scrap to make lining up the dowel holes easy.
Step 9: Adjust Folding Action, Drill Holes
I hadn't made anything which folded up this way before, so I used some scrap pieces of wood to demonstrate to myself how the folding mechanism would work. The legs and supports basically form a diamond which folds to bring the two sides flat together (in theory!)
In reality, the back support did not want to fold fully flat against the steps. D'oh!
After a lot of experimenting and thinking I improved the not-folding-properly situation by cutting the tops of the back stretchers at a slight angle, using a simple jig on the tablesaw.
This angle improves the folding but doesn't fix things totally.
I think the correct way to fix this would be to drill the bolt hole in the back stretchers quite a lot closer to the edge of the wood.
Once I was satisfied I had done all I could to fix the folding problem, I drilled the bolt holes. All the holes were drilled in my drill press with pairs of parts clamped together, so the holes would be aligned correctly.
Step 10: Sand
I also ran sandpaper along all of the edges to round them off.
I like to make my projects as accurate, strong, well-made and nicely finished as possible, to push myself to develop my woodworking skills. Although the stepladder will have a utilitarian purpose, that doesn't mean it can't look good.
Step 11: Glue Up
Clamping the back support was quite awkward and it came out slightly warped, but this doesn't seem to matter much in the final product.
I glued the top slats onto the supports two at a time, spacing the slats with a scrap piece of plywood so they were all evenly spaced apart.
Step 12: Test fit and adjustment
I found that the stepladder didn't lock firmly into a level position when open. The plans I was using had a piece of wood at the top of the steps which sits firmly against the top when open, which I left out in favour of a third step.
You could fix this problem in a number of ways, I simply found some small bolts with large heads and screwed them into the top of the step supports, these sit solidly against the top when the stepladder is in the open position.
Step 13: Finishing
The thinned polyurethane was easy to apply and I had no trouble with brush-marks. You do need to be alert for runs and drips though.
I sanded lightly between coats with 320 grit sandpaper. I also took the time to sand out any drips/runs.
Finishing can be the most boring part of a project, but doing a good job at this step can make a big difference to the finished product.
To speed things up, I:
- Wore an old coat to protect my clothes (no need to put on old clothes for each coat)
- Wore disposable gloves (no need to wash polyurethane off hands)
- Used cheap, throwaway foam brushes (no brushes to clean)
Step 14: Final Assembly
Don't forget the washers and lock washers at this point - without lock washers, the nuts will undo themselves over time as you open and close the stepladder.
Step 15: Final Thoughts
If I was going to build this project again, I would see if I could make deeper steps. I was limited by the quantity of wood I had on hand. It works fine with the shallow steps, but deeper steps would be nice.
Now that the stepladder is done, I can see it would have worked fine with two steps instead of three. Not a big deal though.
A slightly wider stepladder would be nice too, it would be that much more stable.
Getting the stepladder to fold flat properly would have been nice. Following the plan more closely would have fixed that. Alternatively, you could make a full-size or scale model of the folding joint using scrap, to make sure that the folding parts will sit together properly when closed.
I think you could build a reasonably tall ladder using a similar layout, but you would want to angle the legs outwards, and then you would need to use something other than dado joints for the steps.
I am quite keen to make more projects with moving parts like this, it is neat being able to change the size of the stepladder for storage. Maybe you could make a fold-out toolbox ... or a transforming coffee table ... the possibilities are endless. :-)