I Made A Ladder!

Yes, I did.

Please note that I did not title this post “how to make a ladder”.

This was for my daughter’s play set in the back yard, which has had my 6-foot stepladder leaning against it for a few weeks now.

I started by leaning a 6-foot length of redwood against the play set to figure out what angle the ladder should lean at.

Ladder
This was close enough to 30-degrees, so I used 30 as my number.
I cut two lengths of redwood to length with matching 30-degree cuts on the top and bottom edges.
Ladder

Then I used a tape measure to mark intervals on both pieces to note where the center of each step should be.
Ladder

I used the table saw and the miter gauge to cut slots at 30-degrees to make the edges of a mortise; and then used a router to freehand cut the insides out (working carefully, the kirf of the table saw cut is enough of a buffer to rout this out freehand).
Ladder
Ladder

Since I’m not very good at measuring, the mortises were all too narrow, so I slapped together a little tenoning jig to trim the ends of the steps (this was easier than trying to cut all the mortises a little wider).
Ladder
Ladder
Ladder

I successfully got all the steps installed on one rail of the ladder (glue and screws), and then realized that I was not going to be able to get all of the tenons to line up on the other rail. There were little imperfections in the wood and construction, and all together across all the steps this was enough to make it impossible to line everything up at once.

So I made a little router jig (read: “I cut a piece of plywood”) to shave a little more wood off each tenon’s width (the tricky part is that the steps were already installed on one side).
Ladder

Meanwhile I was doing a lot of stepping over and around the half-assembled ladder and managed to catch the corner of a step with the underside of my knee…
ladder

REALLY?!?! Not only am I supposed to wear “close-toed shoes” in the garage, but now I have to wear pants too?!

Next you’re going to say I should be wearing gloves!
Lathe compound repair

Whatever.

Ladder

In any case, that last bit of adjusting with the router worked, and I finished the ladder… and then put on some pants and ate dinner.

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Precision Preschmision.

When it comes to manufacturing process, there is a direct relationship between precision and cost: the more precise the product, the more expensive it is.

The reason for this is simple: making precise products requires the use of even more precise tools, and it requires additional steps to measure and verify that the accuracy is within tolerance.

This applies to the home shop as well.

If you want to work precisely, and repeatably, you need to set up your tools perfectly, you need to measure and verify your results, and you need to plan your moves ahead of time, to make sure your plans for assembly and finishing allow you to maintain the accuracy of the components in the finished product.

All accuracy takes time, but there are two different classifications of precision in my mind, and one matters far more than the other.

  • Absolute Precision: making components exactly 3-inches long, or exactly 45-degrees
  • Relative Precision: making components that fit together exactly, with little concern for absolute dimensions

For example: I can make a table with a top that is exactly 6-feet long and 2.5-feet wide, made from 5 planks that are exactly 0.5-feet wide and 6-feet long: this table looks nice, is well made, and is absolutely precise.

OR: I can make a table that is about 6 feet long and about 2.5-feet wide, made with planks that are all the same length and width: The end result looks the same, and has the same quality, but all of my “measurements” are really just making sure the parts fit together. This is relative precision.

Sometimes absolute precision matters: In mass production you need to be able to provide predictable dimensions so that the packaging and usage can be consistent; replacement parts must meet exacting specifications.

But at home it’s often less important that the part be a certain number of inches, and more important that is fits, works, or looks good, whatever the length ends up being.

This is a liberating principle for me. I don’t need to spend hundreds of dollars on Starrett measuring tools to make six cuts of the same length; I can just make the first cut however I like and then keep the setup in place for the next five.

Now, this does require some forethought. If you are planning to repeat the same cut, you need a setup that will allow it. Your bandsaw and tablesaw should have a sturdy fence (but Biesemeyer and Kreg are probably overkill), and you should use stop-blocks and simple jigs where needed.

You may be thinking: “if you’re making something exactly 6-inches wide, isn’t that just as difficultas making something exactly as wide as something close to 6-inches wide?”, and the answer is: …sort of.

You see, I like to start building based on a concept in my brain, and progress through the project adaptively, with the results of each step determining the details of the next.

I don’t want to sit at my computer planning the minutia of the project in Excel when I could be spending valuable time at the bandsaw. And since nothing turns out perfect anyways, my measurements would invariably need adjustment as the project progressed, which then begs the question: Why measure in the first place?

As noted previously, the tape-measure has it’s place, and the blade of any saw should be square to its work surface, but there is nothing magical about hitting the inch within a fraction of a millimeter: These are arbitrary lengths that were made up in antiquity.

The real test of valuable precision is simple: Does it fit? Does it work? Does it look good? If so, it doesn’t matter what the ruler says.

Inca Bandsaw Fence – Part 3 – The Fence

And so we come to the conclusion of the Inca Bandsaw Fence series.

At this stage I had a rail for the fence to slide on, a carriage that follows and locks onto the rail, and a mounting bracket extending vertically from the carriage for the fence itself.

The best material I found to make a fence was extruded aluminum rectangular tubing (about 1.5 inches wide and 3 inches tall). Aluminum extrusions tend to be very straight and since my saw’s table is also aluminum, using a harder metal could possibly damage the table over time.

I picked up a 36-inch piece of the aforementioned tubing as a remnant from the local metal supply store ($2.70 per pound) and cut 16 inches off to make my fence.

The fence needed to be connected to the vertical bracket attached to the carriage. My first thought was to attach it with bolts on the backside of the fence, but then the width of the fence would be limiting the cutting capacity of the saw by a full 1.5-inches. So I decided to attach the bracket to the inside of the tubing.

In order to do this I cut a slot in the bottom of the fence, right along the front edge where I wanted to attach it to the carriage.

Then I drilled and countersank two mounting holes. I transferred the location of these holes to the bracket and then drilled holes in the bracket accordingly.
Bandsaw Fence - Mount
Bandsaw Fence - Mount
Note: If you are a particularly observant reader, you will notice that I showed a picture of the bracket in “part 2” of this series, but here I am claiming that they were drilled as a step in “part 3”.  Well done.

The arrangement of the holes is not merely aesthetic. If the holes were aligned with each other horizontally, they would provide only limited vertical support. Likewise vertical holes would provide limited horizontal support. My theory is that diagonally arranged holes will be the best of both worlds.

Bandsaw Fence - Mount

I inserted brass (because it’s pretty) machine screws through the holes and secured them with washers and locknuts (to prevent loosening during operation).
Bandsaw Fence
Bandsaw Fence

And that’s it.

IMAG1284Bandsaw Fence

There is a bit of flex on the far end of the fence if to apply a lot of lateral pressure, but since my workpieces will be small and kickback is not a concern on the bandsaw, I won’t be pressing hard against the fence, so I think it is rigid enough.

That said, I’ll probably tinker with it at some point to make the far end lock in place as well.

Inca Bandsaw Fence – Part 2 – The Carriage

For lack of specific knowledge and due to a general laziness when it comes to looking things up on Google, I’m calling this part of the bandsaw fence a “carriage”:

fence scribble

(actually, I’m not certain my affliction can be considered “laziness” since I just went through the trouble of drawing a picture instead of just looking up the correct name… maybe I just feel like it is a carriage, whether or or not that’s what it’s officially called).

In any case, after completing the rail, I turned my attention to the part connecting the fence to the rail.

Essentially this works like a C-clamp, with the rail being pinched between a screw and a pressure plate. The construction may vary, but the most important aspect is that the carriage must be designed so that it is rigidly square with the rail when it is tightened in place.

I used a small piece of angle iron to act as the pressure plate. I shortened one side of the “L” (the “pressure plate” side) so that it wouldn’t hit the bolts on the underside of the rail.

Then I attached a vertical piece of steel that I milled flat and square. I kept it parallel to the angle iron by clamping a piece of metal in between it and the short end of the angle while welding it.

I drilled and tapped 1/4-20 threads into the vertical piece of steel and ran a Rockler star knob through it.
IMAG1232Bandsaw Fence - Slide/Lock

Bandsaw Fence - Slide/Lock

This tested okay, but I didn’t want the screw to mess up the rail over time, so I added a thinner piece of steel that was flexible enough to allow the fence to move while the knob was loose and still bear down hard on the rail when the knob was tightened.

Bandsaw Fence - Slide/Lock

So now I had an assembly that could be locked into any location with a mounting surface that was consistently parallel to the rail. The next step was to make a bracket that the fence itself could attach to.

I made the bracket out of a piece of trailer hitch tube I had leftover from another project.

I started by milling two sides flat and square with each other.

Bandsaw Fence - Mount

After that I cut off the other two sides and shortened one side so that the other would stick up above the bandsaw table perpendicular to the shorter side which would be mounted to the rest of the carriage assembly.

Like so:

Bandsaw Fence - Mount

I mounted this with a single 5/16″ bolt through the carriage assembly, which allowed it to be pivoted as necessary to keep the upright portion vertical (parallel to the blade).

Bandsaw Fence - Mount
Bandsaw Fence - Mount

And now I could turn my attention to the final component: Part 3 – the Fence!

Coming soon.

Inca Bandsaw Fence – Part 1 – The Rail

My little Inca bandsaw, which I love, came without a fence. For many uses this is okay, but the functionality and precision really are limited without a fence, so I set out to build one.

Outside Front

I picked up a piece of 2″x4″ rectangular extruded aluminum tubing from the local metal supply store to act as the fence itself, and for the rest I used other scraps of angle iron and trailer hitch tube I had saved from previous projects.

There are basically three parts to the fence assembly (and three corresponding blog posts):

  1. the rail
  2. the carriage
  3. the fence

The carriage and the fence are connected to each other and slide along the rail to set the distance between the blade and the fence. The carriage must be able to lock itself in place at any point along the rail.

My typical approach to any project is to just start building and figure things out as I go (for typical results, see my cyclone separator). I tend to rely on relative measurements (“about this big…”, or “the same size as that…”) rather than actually measuring with a ruler or tape measure. Since this project required a greater level of precision than my typical project, I did nothing different (I’m not entirely certain where my ruler and tape measure are anyways).

Bandsaw Fence - Rail

I determined the length for the rail by marking a piece of scrap hardboard while holding it against the bottom of the saw’s table.

After cutting the rail (a piece of 1″ angle iron) to length I used the same process to determine the proper location for the mounting holes. I drilled the holes a little large, so that there was some slack for adjustments.

Bandsaw Fence - Rail

Short segments of angle iron are pretty straight but they have some scaling and bubbling from the forging process which I filed off and sanded a bit to ensure that the surface was flat (enough).

I happened to have a couple of metric bolts and lock washers that fit the threaded holes in the table, and installed the rail.

Bandsaw Fence - Rail

Next step: the carriage…