Plywood Door – Part 3

Continued from Plywood Door – Part 2 

After the assembly was complete, I turned my attention to the hinges. Since the door was heavy (a full sheet of plywood and a large pane of 3/8-inch tempered glass), I bought four commercial-grade 4-1/2-inch hinges for the job.

Plywood Door - Hinges
In order to flush-mount the hinge I had to cut mortises in the door and the “jamb” (the 4×4 post the door would hang from).

I planned to use a 1/4-inch straight bit with a brass template bushing in my router to cut the mortise, so I needed to make a template that was slightly larger than the hinge itself to account for the diameter difference between the bushing and the bit.

Plywood Door - Hinges

Plywood Door - Hinges

To accomplish this I measured the diameter of the bit and the bushing and then divided the difference to get the difference in the radius (what’s the plural of radius? Radii? Radiuss?).

Plywood Door - Hinges

I traced the hinge on a piece of plywood (hanging the pin side over the edge by the same amount I wanted it to protrude when installed), and then marked a second line with the radius offset on all three sides.

Plywood Door - Hinges

Plywood Door - Hinges

I cut the offset line out with my scroll saw because it makes narrow, precise cuts and leaves a clean edge that requires no sanding or cleanup.

Plywood Door - Hinges

Plywood Door - Hinges

I measured out arbitrary locations for the hinges along the door and marked the center line of each location. I also made a note of the distance between each center line so I could reproduce it on the jamb to hang the door.

Quick tip: In order to keep the door stable while working, I used Rockler Clamp-Its as feet while marking and routing the door:

Plywood Door

Because the glass was already installed, I didn’t have a wide enough surface for the clamps to grab to hold the template in place, so I clamped a plywood strip to the face of the door and clamped the template to that instead.

Plywood Door - Hinges

Plywood Door - Hinges

Cutting the mortises went quickly and smoothly, I just lined up the front edge of the template with the face of the door and made sure the center line of the template was in sync with the hinge location marking, but I wished I had a wider base on the router to hold it more securely in the parts of the cut furthest from the template edge.

Plywood Door - Hinges

Plywood Door - Hinges

I spent a few seconds on each mortise with a chisel to square up the corners and then installed the hinges.

IMAG0189Plywood Door - Hinges

Plywood Door - Hinges

I measured and marked the hinge locations on the 4×4 jamb (offsetting by the distance above the ground I wanted the door to swing) and followed the same process there, reusing the same template.

It occurred to me that I didn’t want bare wood underneath the hinges, so I removed them from the door for painting. I didn’t paint the edge of the door opposite the hinges (facing the ground in the below picture), because I planned to fine-tune the fit after hanging the door, and didn’t want paint to gum up the tools I would use to accomplish this.

Plywood Door - Paint

Plywood Door - Paint

Plywood Door - Hinges

After painting the door and the jamb, and giving everything a day to dry, I installed the door.

Did I mention that this door was heavy? As far as I know I’m not at risk for a hernia, but if there was ever a time that I came close to popping out an organ, it was while wrestling this door into place on top of a pile of shims to balance while I got the first screws in.

Surprisingly, once it was installed, the door didn’t seem all that heavy any more. I had expected an unreasonable amount of inertia, and was worried that the door would be prone to removing fingers and wrecking any latches I would use to secure it, but it actually feels very nice. Just like a good, solid door.

It was hitting the jamb opposite the hinges in some areas, but this just took a few minutes to fix with a little Rockwell power plane I have. No wonder these are a favorite of door installers, this thing was perfect for this application, and now I have a nice even gap along the length of the door and it all works beautifully.

I installed the latch up high to keep it out of reach of kids, and higher than required so that the pin was not sticking out at eye-level (no point in adding adult-hazards for the sake of child-proofing).

My daughter was thrilled with the result.

Plywood Door - Install

Plywood Door - Install

Time will tell if there is any deficiency in plywood as a door material, but as far as I can see, I’ve got a beautiful, sturdy door that serves its purpose perfectly.

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Filling Space

I suspect most people with milling machines fit into two categories:

  1. Professional machinists that use their machine on a daily basis
  2. People with too much disposable income and garage space that bought a machine on a whim and now primarily use it to prevent dust from reaching the floor

Although I may be wrong, I think people like me are a bit of a minority within the population of milling machine owners. I have no occupational prerogative for such a machine, but I use it all the time, for all sorts of things, whether or not it’s “necessary”, or the “proper” tool for the job. If it can be done with the milling machine, it will be done with the milling machine (or at least attempted).

The most recent use was to create a few spacers to fill gaps in my pergola. I had assembled a horizontal beam from two 2×6 boards and set it on top of 4×4 posts, but the combined width of the 2x6s was actually a bit thinner than the 4x4s, leaving an unsightly gap in the connecting bracket.

My work my not be precise, but I try to make it look good.

I needed to fill about 1/4-inch.

I happened to have some 1/4-inch plywood that would work for this task.

<start humming inspirational tune>

But I also happened to have a milling machine, so such band-aid fixes will not suffice! 

If I have the means and materials to make a spacer that will outlast the structure, the bracket, and likely human civilization itself, I will avail myself of such means and materials!

So I cut some squares out of a piece of aluminum tool plate (same piece I used for my miter saw fence) with my portable bandsaw (I love), and then used my milling machine to batch them square and bring them to their final dimensions.

Post Bracket Spacers

Post Bracket Spacers

Filler

Filler

I made a paper template and marked the hole locations on the newly square plates, which I then drilled out on the drill press.
Post Bracket Spacers

Post Bracket Spacers

Post Bracket Spacers

Space filled. Problem solved. Milling machine used.

<stop humming inspirational tune>

Plywood Door – Part 2

Continued from Plywood Door – Part 1

I picked up a sheet of multi-ply from home depot for $40. I like the Araucoply more than the “cabinet grade” plywood because it doesn’t have a delicate veneer layer that is prone to chipping during cutting and blistering when exposed to the elements; instead it has full-thickness layers front to back, making a more durable product for my purposes.

I cut the sheet down, according to my Sketchup plans, into strips wider than necessary for the final product.

I stacked and cut the similar sized pieces all at once on my 12-inch sliding miter saw; it was perfect for the task.
Plywood Door

Plywood Door

IMAG0117Plywood Door

Then I laminated the pieces together with waterproof glue and left them overnight.
Plywood Door

Plywood Door

Plywood Door

A quick tip: Buying a gallon of glue is cheaper than buying the small bottles for a project like this that requires a lot of glue. To dispense the glue during the glue-up, I just poured it into a disposable water bottle with a slot in the lid and threw away the bottle when I was done.
Plywood Door

After the glue dried, I cleaned up the squeeze-out with a block plane and ran the new 2-1/4″ thick plywood timbers through the table saw once on each side. cutting them down to final dimensions.
Plywood Door

This is an important step. I could have theoretically eliminated the need for this by cutting the plywood strips to the final dimensions in the first place, but it is nearly impossible to prevent a little slipping between the pieces during glue up, and after the glue dried I would have to even out the edges and ended up with a board that was narrower than intended.

Next I cut the ends at 45-degree angles and ran them over my router table to cut a 1-inch deep slot 3/8 of an inch wide down the length of each piece to accept the glass pane.
Plywood Door

This was my second time using the spiral cutter on my router table for a major project, and I must say I love it. I always got a significant amount of chatter on all but the shallowest cuts with a standard straight bit on all but the shallowest cuts, but the spiral cutter handled full-depth (1-inch) cuts smoothly and without complaint.

Quick dry-fit to make sure I hadn’t done anything stupid… all clear… this time.
IMAG0126Plywood Door

I cut 4 squares and notched one of the corners on each square about 1-inch.
Plywood Door

These notched squares would act as something between a tenon and a biscuit (or possibly a spline) to hold the corners together. The notch was needed to act as a continuation of the slot the glass would set in.

I attached three sides together, leaving one side open to later install the glass (the below picture shows the final side in place, but it is a dry-fit to keep things aligned while the other end dries).
Plywood Door

After the glue dried, I temporarily clamped the fourth edge in place and routed a decorative bevel around the inner edges of the front and back. Since I routed after assembly, I had to define the corners in a second step with a cabinet maker’s rasp.
Plywood Door

Plywood Door

You may be thinking: “why didn’t he use the router table to cut the bevel before assembly? Then he wouldn’t have had to clean up the corners…”

This is true, but at the time I would have routed the bevel prior to assembly, the baby was sleeping, so I decided to take advantage of the time doing the quieter assembly activities, rather than waiting till the next day to make any further progress.

Once the bevels were cut, I applied a small amount of silicone caulking to the inside of the slots in the frame and slid the glass into place.

The glass didn’t seat as deep in the slot as I hoped and so I had to dredge the slot in the final piece by another 1/8-inch on the router table to get everything in position to glue the frame segment in place and complete the major assembly.
Plywood Door

Coming Soon: Hinge Mortises, Paint, and Lynching!

Plywood Door – Part 1

Pools + Babies = Significant legal liability

All access points to pools must be secured with self-closing mechanisms and latches at least 54″ off the ground. Swinging-style doors and gates (as opposed to sliding doors) must open away from the pool, so that a latch failure will not allow a child to push the door/gate open.

My back yard is compliant with this, but once you are out in the back yard there is nothing separating anyone from full access to the pool. And I would really like having an outdoor area that my family and friends could be in without worrying about the kids being combined with the pool in any unplanned way.

This is why I am building a pergola off the back of my house.

pergolaPlan

The barrier to the pool is a deck railing of wood and tempered glass, and I would normally make a gate the same height as the railing, but I want to place the latch up high, and I think there are better looking alternatives than the commercial pool gate latches.

So rather than building a gate, I’m building a door.

The opening I am filling is just over 40-inches wide, so it will be a big door. And I want the door to feel like it belongs with the rest of the design, which is very open with large glass panes, so it will have a large single sheet of 3/8-inch tempered glass within the frame.

I did a little research into the best wood to make a door out of, and the two woods people recommended most where white oak and mahogany. I eliminated Mahogany quickly, because I don’t want to pay for it. White oak was interesting, but even then I would pay around $100 for the wood, and I’m stingy. I considered poplar, which is cheaper, but there were a large number of warnings against using it for doors due to warping in exterior conditions, which would be bad for my application (which is essentially a wooden frame around a large piece of glass).

So I needed something inexpensive that could handle weather and stay perfectly straight. It then occurred to me that Plywood might be the answer.

I didn’t find anything online indicating that this was a bad idea (not that I would have listened anyways).

I could buy a sheet of good quality multi-ply and build it up into the thick timbers I needed by gluing layers together.

Building the frame out of layers would make it a simple matter to use a form of mortise and tenon joinery in the corners that would make this a very strong frame; which it would have to be, considering that it would be made of a nearly full sheet of 3/4-inch plywood and a 6-foot by 32-inch piece of 3/8-inch glass and would easily weigh over 100-pounds.
Before rushing off to Home Depot, I did a quick proof-of-concept in Google Sketchup, just to confirm that I could make everything out of a single sheet of plywood.

Plywood Door Layout

It all worked out in theory, now for reality.

(To Be Continued…)

Miter Saw Fence

I have a monster of a miter saw.
Plywood Door

It’s a 12-inch sliding compound miter saw that I picked up from a guy on craigslist. It’s awesome.

However, I’ve been using it a lot lately and have been noticing that the angles need a lot of fine tuning to get exactly 45 or 90 degree cuts.

At first I thought it was just the positive lock mechanism needing some tweaking, but on closer examination, I found that the problem was the saw’s fence itself.

If I held a straight edge against the fence, I could see that both sides (although one more than the other) drifted further back as the neared the center, and the two sides were not parallel with each other.
Miter Saw

This meant that the angle of a cut could be wrong in three ways, depending on how I held the board (one angle if the board referenced both fence surfaces, and another angle for each of the two surfaces alone if trimming the end of a board).

I know I’ve recently outed myself as something of a rebel when it comes to precision, but not being able to cut at a specific angle when needed is always a bad thing.

But how to correct this? The fence is a single piece of cast aluminum, and can’t be bent without breaking, so I couldn’t just straighten it out, I needed to fix the surface.

When I looked more closely I saw that the fence was not bent out of shape, but rather worn out of shape. The saw had been previously owned by a production shop that used it almost exclusively for cutting aluminum, which apparently, over time, had worn down the fence.

So then I thought the solution might be the milling machine (to be perfectly honest, I try to use the milling machine as the solution to almost every problem). The difficulty with milling the surfaces flat would be keeping the fence perfectly parallel to the milling table in two different clamping positions to address each side. Ultimately this seemed like a big risk.

Then I noticed two 1/4-inch holes on each side of the fence, and realized that the solution was to add an auxiliary fence to the saw.

I wanted the fence to be rigid and thin (so as not to reduce the cutting capacity too much), and I decided to make it out of 1/4-inch thick aluminum tool plate (I had some laying around that I picked up as a remnant from the local metal supply store).
Miter Saw

I roughly cut two 3-inch wide strips and squared the edges on the milling machine (I knew I needed it!). I then marked the locations of the holes and edges in order to keep from mixing up the two parts, and then countersunk and drilled holes (in that order) to line up with the holes in the fence.
Miter Saw

Unfortunately I countersunk the wrong side of each piece, but luckily the hole positions are mirror images of each other on the left and right sides of the fence, so I just pretended I meant to do that and casually attached them to the opposite side with beveled machine screws and nylon lock nuts.
Miter Saw

That’s it.  Now I have a straight and sturdy secondary surface that I can shim if necessary to get a perfectly true alignment and then never think about again.