2013/06/19

Teardrop Update

This post is way overdue, and to prevent it from being even later, it is being done without photos.

We have been making consistent progress, but as with most things, it seems we take two steps forward and one back.  None of our recent projects are complete, which explains the lack of photos.

First issue:  The gas struts and mounting brackets arrived last week.  We proceeded to mount them.  I was pleased that the dual 150-lb. struts appeared to be a correct choice for the load the hatch presents.  Even though the hatch weighs only about 80 pounds, the force applied at the strut attachment point is far greater.

As I was closing the hatch for the first time under "strut power" the resistance felt good.  However, when the hatch was within 10 degrees of full closure I failed to provide resistance to slamming, and slam it did.  With all struts - think of the hatch on your car, if you have one - the last bit of closure enjoys little to no resistance from the struts.

When we opened the hatch, we found that three of the four mounting brackets had deformed.  It is unclear whether this was from the slam or from the fact that we may have mounted them too close together.  The selected strut has a compressed length of 14.8 inches.  We may have pushed this boundary.

In any case, we determined that the manufacturer-supplied mounting brackets are inadequate for the forces at play.  So, I designed two types of mounting brackets, ordered up some stainless steel studs with 5/16" x 18 thread mounts and the correct 10mm ball heads, and went down to a local welding shop with the drawings and asked them to fabricate plates from 1/4" stainless steel with holes for mounting and holes for the ball studs.  We should see these soon.

The new plates were designed to have the closed position slightly farther apart than the original mounts, hopefully avoiding over-compression.  One of the struts tends to deform sideways when we start to close the hatch.  I have already located a substitute strut with a larger diameter rod - aka, beefier construction, should it be required.  

Second matter:  Sean has been working diligently on the wiring.  We have located several fixtures/lights/etc. so that he can bring the wires to the correct points.  We've done some work in the battery box to "locate" the batteries so they do not move around while in-transit.

Of course, there are a raft of dependencies.  For instance, today he was looking to run the wires to the water pump which will automatically turn on when you open the faucet.  Well, where does the pump mount?  That depends on several things:  sink placement, water tank placement, and the placement of the faucet and filter cartridge.  So we spent some time locating all of these items to determine where the pump could mount so no water lines will be kinked so Sean could bring the wires to the correct location.

The location of the faucet also fed into another issue:  I want to have a stainless steel countertop.  I have created a drawing and a template for the piece, including the cutout for the sink.  But, I needed to locate the faucet to have that hole drilled by the fabricator.  

Third matter:  Recently I constructed the tray for the cooler (middle bay under the counter) and the drawer for the gas stove (right bay).  I purchased the full-extension heavy duty drawer slides for these two "drawers" and proceeded with fabrication.  I wanted to detail the faces with rosewood inlays in oak, so I proceeded to find leftover pieces of rosewood to determine what I could do.  I decided on two thin pieces horizontally 3/4" up from the bottom edge with a space between them.

A nice detail, but when I set the saw to make the second groove in the drawer faces I neglected to allow for the width of the saw cut and ended up making the second cut leaving little to no oak remaining between the cuts.  Well, at Sean's prompting, this bug was turned into a feature.  The two very close cuts were turned into one inlay, and another cut made an appropriate distance away, resulting in one thin and one wide inlay.

In the end, I think this result will be visually more appealing.  The rosewood has been glued in and sanded flush.  Finish sanding is required on the faces, after which I will take photos.

Last matter:  When we assembled the wall structure and added the inside layer of 1/4" birch plywood we needed to cut the openings for the doors and windows.  The doors and windows have radiused corners. Rather than try to cut these curves with a sabre saw I purchased a 6" hole saw (just the right diameter).  We mounted the hole saw on a right-angle drill and proceeded to cut out the corners of the openings, then use a circular saw for the straight cuts.

Well, controlling the hole saw, even with a heavy-duty right angle drill and the wall lying flat on a table so that the hole was being drilled vertically, was very challenging and imprecise.  I was ruminating on this experience and contemplating how to cut the openings once the outer 1/4" birch plywood is applied, and again once the skin is on.  I knew the 6" hole saw was not the solution, especially given that it would be a horizontal drilling on a vertical wall.

The idea arose to build up 1.5" thick pieces of poplar 6"+ on a side, drill the 6" hole on the drill press, then cut the outer part into four 90-degree arcs.  These pieces would then be installed at the corners of the openings inside the wall.  Once the 1/4" birch is applied, a router can be used with a trim bit to cut the opening.  Same for the skin.

Yesterday I glued up the four blocks required.  Today we set up the drill press and started drilling.  Well, only for a short while.  The main issue was that the resistance to the 18"+ long cut (6 inch diameter times PI) with even the lightest pressure on the drill press was enough to jar the chuck free of the drill press shaft.  This chuck is a tapered fit onto the shaft, where friction keeps it in place.

So, Sean to the rescue with the suggestion to use the band saw.  I replied that the hole saw could be used to score the surface of the block and thereby create the circle to be sawn.

Sean, sawn.  Whatever.

It worked quite nicely.  Any casual observer would have thought that we were creating some 6" by 1.5" wheels from poplar, but in fact I was interested in the "leftover" parts.  I cut each leftover (a square with a round hole in the middle almost as large as the square) into the four "corners" I needed.  Using the stationary belt/disc sander, I custom fit each corner using the appropriate trim ring, glued and nailed each into place.

In so many ways and in any number of instances, we have attacked a problem, been set back by unexpected or unanticipated issues, regrouped, designed a solution, and implemented the solution.

In other words, much of our journey has been creative problem solving.  And that is one of our strengths.

Next steps: 

  • Obtain the custom-fabricated stainless steel brackets for the gas struts, fabricate the wood support blocks, install and test.
  • Finish sand the cooler tray and the stove drawer, mount.
  • Obtain the stainless steel counter top and stove drawer top, install.
  • Mount the sink and faucet.
  • Once the wiring is in place, connect the pump, tank, filter and faucet.
  • Create the oak facing for the lower part of the galley, design and fabricate the closure (door?) for the sink/tank compartment.
  • Create the system to hold the two propane tanks in place, connect tanks to stove (having mounted the stove).
  • Mount the mahogany dowel under the hatch that will hold the two LED worklights for the hatch.
  • Once the wiring is complete and tested, reinstall the insulation on the sides, insulate the top, install the 1/4" skin on the sides and the two layers of 1/8" skin on the top.
  • Install the filon skin over all surfaces.
  • Create the cabinet closures (probably tambour) under the hatch.
  • Create the cabinet closures (probably tambour) in the cabin.
  • Finish sand and urethane/lacquer all wood surfaces.
  • Get the exterior painted professionally at an automobile body shop.
 Well, we have a lot more to do!

      

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