Saturday, March 28, 2015

Portable Flea Market Display Case, part 4

(Go back to part 3)


An oak "mud foot" adjustable leg leveler.

To make the mud feet, I resawed and planed a length of 3" wide oak. I hollowed out the insides with a series of forstner bits (using a hand-held power drill), then epoxied in the feet of threaded leg levelers.

Once the expoxy had cured, I sawed them off into squares, sawed the corners off and rasped them to round, then applied finish. I attached the threaded sockets to the bottom of each leg.

I attached the locking hinges to the legs and then to the oak baseplates. I screwed in the mud-feet and closed down the hinges. This revealed my next mistake. Can I say how much I hate dealing with hinges?

This was another case of small problems adding up. First, slight alignment issues in the hinge installation meant that the legs bumped into each other instead of laying down flat alongside each other. Second, the sizing of the mud feet and width of the leg assemblies meant they wouldn't fit properly even without the alignment issue.

This was a more significant mistake than the others. Finally, I drew inspiration from my friend Freddy Roman, maker and restorer. He does a lot of repairs of failed joints, particularly on chairs. He doesn't waste a second of hesitation before cutting them off and remaking them.

Similarly, my wife is an orthopedic surgical nurse who does a lot of joint repairs. They go right in, cut off the old failed joint, bone or metal, and make a new one. Orthopedic surgeons probably make great woodworkers!

OK, so just do it. I could cut one side off each leg assembly, excavate the mortises, recut the tenons, touch up the finish, and the narrower assemblies would fit properly, with some margin for hinge alignment.


Ouch! Cutting off a leg stretcher.


The cutoff ready for remaking the joints. The rest of it went fine.

The next step was flocking the interior. I had never used this material before. The brand is DonJer. The instructions said it was easy, regularly used by junior high school students on their projects, and recommended consulting one in case of difficulty. Since I was fresh out of junior high school kids with mine off at college, I was left to flail on my own.

The setup consists of a bag of shredded flocking fibers, a can of glue in matching color, and a cardboard tube pump applicator. The glue is like a heavy paint. The fibers are very light and a bit dusty.

I taped off the finished edges of the case and painted the interior of the right side with the glue. I poured some fibers into the tube and pumped them uniformly across the wet glue. The process was just as easy as advertised.

The only problem was that I was a little light on glue application. The instructions said to spread it thickly with a brush or roller. I used a brush, but didn't use quite enough. This left slightly visible thin streaks in the flocking against the light colored wood.

I went ahead and did the left side. This time I applied glue generously in the naval fashion: if it moves, salute it, if doesn't, paint it. Thickly. The results were much better, a good uniform coating and flocking.

The instructions said to let it dry for 10-15 hours before reclaiming loose fibers, and allow 72 hours to a week for final curing. While I gave it time, I contemplated what to do about the streaks. I thought about trying to do a second coat, but wasn't sure how that would turn out.

In the end I decided to strip it down and redo it. I used a card scraper to remove it. I'm happy to say this was much more difficult than I expected. That glue and flocking are tough stuff. It certainly eased my mind about the surface getting torn up in use.

I still had enough glue and fibers left to do a thorough coating, and the end result was as good as the other side. After the glue has cured, it feels like velvet stretched tight on the wood.


Flocking applied to both side.


The setup: glue, pump applicator, and fibers.

Next step was installing the acrylic panels in the doors. You cut this stuff sort of like glass, scoring it repeatedly with a knife along a straightedge and then snapping it off.

I wasn't thrilled by the knife sold for this purpose, so I ended up using the chip carving knife that I use as a marking knife. I also ran a veneer saw along the straightedge to cut faster.


Probably tool abuse, but a block plane along the snapped-off edge does a great job cleaning it up and paring it down for precise fit. This still has the plastic wrap facing on it to protect against scratches.


Boring screw holes for the backing strips with a birdcase awl. I've already installed the piano hinge to the doors.


With the acrylic in place after pulling off the facing, screwing down the backing strips.

The final step was installing all the hardware. The piano hinge gave me almost as much heartburn as the leg hinges, but I eventually got it.


Rear view showing the handle, door latches, and screw eyes for securing to chains.


Side view showing a brass lid support.


Side view closed up.


Underside view with legs unfolded...


...and folded. The hinges latch in both positions. It does take a bit of coordination to unlock both hinges and move a leg assembly using only two hands.


Front view in folded-up tabletop mode.


This does mean several inches of interior capacity are lost to the legs storage underneath.

While the locking hinges worked well, they had enough mechanical play in them to make the stand rattly. After all this effort I wasn't going to allow that. I made thin oak strips to act as leg braces. One strip on the near side of each assembly, secured with carriage bolts and wing nuts, was sufficient to make it rock solid.


The latch release on a hinge. The hinges are through-bolted to the legs and bottom as well as screwed, to prevent tearing them off if something crashes into the side.


An oak leg brace.


Securing the brace to a leg unit.


The brace secured to leg and case.


Underside view.

This was good starter project. It was big enough to help expose and sort out several issues, yet small enough that the downside was acceptable. Now I know better for future clients!

2 comments:

  1. Nice project. I like your level of detail, just right.

    I have found out that one can cut acrylic fairly easily with the plywood japanese saw that Lee Valley sells. Works even for the thin home depot acrylic. Also when planing thin acrylic it comes off in a spray of little particles which can be contained by putting a towel on top of the plane. Thicker polycarbonate (lexan) comes of in nice shavings and also saws easier.

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  2. Most acrylic is cut with a zero kerf blade and to clean saw marks a straight router but is used and it can be polished after that if its to be glued ect. I don't think it's tool abuse to use the block plane because I have done the same thing I think tool abuse is hanging them on a wall and not using them as well as using a tool and not sharping is tool abuse.

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