davepolaschek

A while back, my sweetie expressed a desire to have a bedside lamp and a night light. I worked with a few different ideas for the lighting part of it before finding the Lanterna 3-Stage Battery Powered Lamp at Lee Valley. It’s just about exactly what I want, except it takes 3 C-cells. More on that later.

So I started by making a twisted tangential turning roughly the shape I wanted for the lamp base.

I also went searching for a rechargeable battery for the lamp. Turns out our door cameras have a battery which is just about perfect. The battery has charging circuitry built-in, and the terminals are on one end of the battery, and the charging jack on the other, so I ordered a spare battery. The only question was whether the 3.7 volt battery would drive the light circuit which was expecting 4.5 volts (yes, yes it does).

Then I disassembled the Lanterna and figured out what I could use. It was pretty easy, as there is a ⅜ inch threaded rod down the middle of the lamp holding everything together and carrying the wires from the head to the base. All I needed to do was cut off the battery holder, shorten the rod to fit my base, and then solder the wires onto the rechargeable battery terminals.

Then because my base was a little short, I cut a piece of walnut and carved out a battery-shaped hole in it, leaving the hole just large enough to slide the battery through, but tight enough that the battery won’t fall out when you pick up the lamp.

With the walnut base glued to the twisted base, finishing was just a matter of a few coats of danish oil, a coat of shellac, followed by two coats of violin varnish, and then a thin layer of carnauba wax so the lamp should be easier to dust.

My sweetie thinks it’s wonderful.

Technical notes: the battery charging circuit may not support operation of the lamp while charging. I don’t think this is a big problem, but that’s part of why the charging jack is on the bottom of the lamp. It’s less tempting to try and use the lamp while it’s charging this way. Also, Ring doorbell batteries are about half the price of the TP-Link batteries, but the charging jack and battery terminals are on the same end of the battery. Depending on your design, this may be good or bad.

Finally, the three stages of the lamp were chosen fairly well. The dimmest is slightly too-bright for a night-light, but putting a colored lens in front of the LEDs would solve that. And would be easy given the way the lamp screws together. And the current draw is low enough that the lamp should last 10-20 hours at full power, and almost a full week in nightlight mode. I think that’s a pretty decent life.

#project #lamp #woodworking #woodturning

Discuss...
Reply to this in the fediverse: @davepolaschek@writing.exchange