HOW TO MAKE YOUR OWN PERIOD LOOKING FLUORESCENT CAMPING LANTERN
by Cian of Storvik, Kingdom of Atlantia


The purpose of this instruction is to make a period looking lantern for camping that produces more illumination and is safer than an exposed candle. This will show you step by step how to make your very own horn pane lantern in a style similar to one recovered from the wreckage of the Flag Ship Mary Rose (c. 1545) Simple lanterns like this date back much earlier in the middle ages. And though similar, some creative changes were done to make the final product as user friendly as possible. Please read through the directions completely atleast once before starting this project so you understand the processes. Note that the only locations that are to be glued are the sides of the door, and the parts of the chimney detail.

EXTANT EXAMPLE: THE MARY ROSE LANTERN

I really don't know much about the Mary Rose Lantern, except for what I have gleaned from images viewed on the web. It appears to be a very simple wooden candle lantern with approximately 6 or 7 vertical slats. The top appears to be turned with a typical "chimney" detail as seen in many lantern illuminations of the period. There also appears to be a bit of a ogee detail on the edge..

The dimensions of the Mary Rose lantern are not known to me, but scaling it for our project so that the lantern internals and wiring will fit, makes the over-all dimensions of this project 7" diameter by 11" tall with 1" wide slats. You can use these directions and plans to simply make a period looking candle lantern as the Mary Rose find by ignoring the electrical instructions and opening the chimney up in the top.

FUNCTION OF A LANTERN

If you didn't already know, a lantern is primarily a piece of furniture with or without a handle, that contains a candle and prevents the accidental contact of the flame which ostensibly could burn you or set a flamable object, such as clothing, on fire. Unlike a candle holder, which simply provides a stable base for the candle, a lantern will usually have semi-transparent or clear panes which allow the light to escape, but keep the flame contained even if tipped over. The lantern also protects the flame from being blown out by a gust of wind or accidental contact.

LIGHT ELEMENT

There is nothing wrong with candles except that individually they do not produce a lot of light. Low voltage lighting has the advantage of producing a minimal amount of heat and no open flame, yet produces a radiant light source that is much brighter (requiring less of them to illuminate an area) and less likely to cause eye strain. For this project I am using the most cost and energy efficient type of light source I am aware of; fluorescent lighting.

I'm using the 9watt fluorescent U-tube 4 pin-base bulb that has come with the lantern, but similar bulbs are also available in 5, 7 and 13 watts in similar shape. Some people have suggested that I use LED (Light Emitting Diodes) technology, to create the light source, and though some numbers look promising, but LEDs are still not as efficient as fluorescents with regards to "radiant" light. That is to say, LEDs cast light in a direction usually in a beam or cone of about 5 to 120 degrees and are usually measured at their optimal output. To build an array of LEDs that will cast light equally in 3 dimensional space like a candle, incandescent bulb or fluorescent bulb, is not only difficult and cost prohibitive. An LED will use energy faster then a fluorescent bulb of similar luminescence. LEDs also tend to have a narrower band of light then natural light. They can have a blue, yellow or white cast to them, but no LED will produce a broad spectrum of light waves as we get from day light (which is what is best for our human eyes).

COMPARATIVE LIGHT SOURCES
I don't want to confuse you with mathematical calculations and theories of determining perceived light output, spectrums, stradian, foot candles etc. Suffice it to say that we're all familiar with incandescent bulbs, and how they radiate light in all directions and they are usually marked with an approximate "lumen" output or luminosity on the box. A lumen is the sum of light that the source is eminating in all directions and that is the bottom line I am going to give you as a source of comparison.
1 candle flame produces 1 candle power or candella of light (1 candle power measured at one foot distance from the source) which is 12.57 lumens of light
A 40 watt incandescent bulb as you find in your oven or in some light fixtures around the house produce about 400 lumens. (cost about $0.50 ea)
A 9 watt array of 150 light emitting diodes shaped like a bulb with a standard B type screw in base will produce about 320 lumens (and is about $60 to purchase as of the writing of this article)
A 9 watt PLSE, G23 base, fluorescent U-tube as is found in some camping lanterns produces approximately 580 lumens (and costs under $5 to replace)

Note that you would need over 46 candles to produce the same luminescense of a 9watt compact fluorescent bulb. And at our current technology, the lumens per watt output of LEDs (30 lumens/watt) is about half of the efficiency of modern CF bulbs (60 lumens/watt).

It should be noted that the CFLs I'm quoting do have a lifespan that measures around 10,000 hours, and an LED bulb could concievably outlive the purchaser. It is also note worthy that CF bulbs of the type suggested have complex electronic components don't really like being cycled on and off and the 10k hour time span stated by the manufacturers is approximate for use in optimal temperature and weather conditions. Don't write to me to complain that you only got 900 actual hours of usage out of your bulb after taking it on 10 camping trips.

POWER SUPPLY

The camping lantern I am using comes with a removable holder that you can clip 4-D cell batteries into. And because I already have D batteries, I'm using it for this project. Note you need a 6 volt power source, which means you also have the option of using a single 6 volt lantern battery which is nominally heavier then 4 d-cells, but produces nearly 30% more power. With a 9 watt bulb, you should expect about 15-20 hours of continuous use before needing to replace the battery. For comparison, a 7/8" diameter beeswax candle will shrink around 1" every 90 minutes. So a 9" long candle of this type will give about 13.5 hours of illumination.. Just thought you'd like to know.

Before I get to the actual step by step directions, it's only fair that I let you know what this project requires in cost and skill level. You, yourself, will have to decide if any of this is worth the investment of your money and time or if any part of it is outside of your skillset or if you can work an alternative way around certain steps. Please follow all manufacturer's safety requirements for tools and their use. Use safety goggles and gloves at all times.

The skills that are involved in this project are what I would consder simple wood working (straight cuts and use of a drill of some sort), as well as some simple soldering and basic understanding of electric current and how a switch works. Use of a hand held screw-driver and metal snips. You will also need to flex some some artistic work with acrylic paints if you want to make the imitation horn panes.

Parts list
QtyDescriptionPrice*
1Store bought lantern with replacable fluorescent G23 U-tube bulb. For this project I selected an Alpine Design brand 9watt fluorescent "u-tube" camping lantern. It uses 4 d batteries not included.**$9.99
14 D-cell or 6 volt lantern battery$12.99
2Craft store turned 7" round wooden "plaques"$1.59 ea.
1Craft store turned 4" round wooden "plaque"$0.59
1pkCraft store 2" wooden disks (2 per pack. You only need 1)$0.99
14" x 48" x 1/4" poplar craft board$3.00
1SPST Maintained On/Off push button switch (I used a Gardner Bender GSW-21 available from local hardware elec section)$4.33
1pkMale speed connectors from electronics parts store$
1Piece of 20 ga steel (from local hardware center)$
1pkShrink tubing$
4#8 x 1/2" wood screws$0.89/pk of 6
1#10 threaded rod 4" long or a #10 machine bolt 4" long.$1.99
2#10 machine nuts threaded for #10 bolt/rod above.$0.89 /pk of 4
2Fender washers (I think I used 5/32" and drilled out the center for the #10 rod$0.08 ea
1pcClear or translusent plastic panel 1/16" thickness (Poster frame glazing)$12.99
1pair of small 1/2" brass hinges (Optional)$2.99
Approximate total cost of project$53.50
*Prices are approximate suburban Washington D.C. retail without taxes circa 2/09
**As of 4/09 I have been unable to locate the Alpine brand of lantern as used here, but an identical lantern appears to be available at Walmart made by Ozark Trail 505VA UPC code 0-4983367071-4

Tools Used
Soldering iron
Drill press or 3/8" corded or cordless drill
Dremel tool with rotary wood cutter (or other tool to cut grooves for panes in wood slats)
Drill bits: 3/16", 1/4", 1/2", 15/32", 1" forstner bit, 2" hole saw
Narrow wood chisels (optional)
Drafting/maping compass (preferably) or ruler
Tin snips
Small craft saw
Screw driver

Sundry supplies that may be needed for project if you don't already have them:
Spool of electrical flux core solder
Lighter or other heat source for shrink tubing
Sand paper various 260 to 400 grits
Wood glue
3' of cord (preferably hemp).
Wood stain of your color choice (optional)
Polyurethane clear coat to protect the wood parts (optional)
Assortment of acrylic paints; white and brown particularly (optional)

MEASURING AND MARKING WOOD PARTS:

1)Mark the center point of each of the wooden disks. You can use either a compass or a ruler for this.

2)On one of the large 7" disks, you'll want to measure radially on the top 6 points towards the top, near the Ogee equally distant from each other (Should be slightly under 3" apart). This is where the compass is really handy, adjust the width of the compass until you can flip the compass approximately 6 times around the circumference. Mark each of the 6 points. This is where you are going to drill the 1/4" holes for the vertical slats.

3)On the 7" round disc (FOR THE TOP ONLY) Mark a rectangle approximately 1" x 5/8" for the body of the on/off switch to fit into.

DRILLING & CUTTING:

4)Drill a hole through the center of the 2" wooden disk with the 15/32" drill bit.

5)Drill a hole through the center of the 4" wooden disk with the 2" hole saw. You also at this time may wish to sand down the ogee'd edge to look more like the chimney on the Mary Rose example (optional).

6)Using the 1/2" drill bit, drill two holes through the rectangle you marked on the single 7" wooden disk. This will remove enough material for you to finish squaring off the sides to the proper 1" x 5/8" size for the switch (Confirm with the switch you purchased). Note that the chimney and 2" disk will cover this hole, and so it doesn't really need to be this neat. You could simply take a big old 1" hole saw or your forstener bit and drill a 1" hole through the 7" disk. You may have to remove a little bit extra for clearance for the wires that are on the side of the switch (see picture).

7)Drill the 6 holes that you marked around the circumference of one of the 7" disks using the 1/4" bit. *Make sure the drill bit penetrates perpendicular to the surface of the disk*. It's very important you make these holes square to the piece, which makes a drill press the best choice for this operation, but it is doable with a hand drill. You can now set this disk centered on top of the other disk and use it as a template, drilling down through to the disk underneath. This will ensure proper alignment of the vertical slats. Use a pencil to mark proper alignment so that you don't rotate the disks misaligning the holes you just drilled.

8)Using the 1" forstner bit, drill a 3/8" deep 1" diamter hole as a recess in the center of the base plate for the bolt.

9)Use the 3/16" bit to drill a hole in the center of the disk for the base. This will allow you to pass a bolt through to mount the battery pack.

10)Also use the 3/16" hole to drill 2 holes in each 7" disk to pass a rope through, in the case that you want to have a handle or way to hang the lantern.

11)Rip/Cut 4 identical 11" long by 1" wide slats from the 1/4" x 3" poplar boards. (I suggest you use poplar or some other hard wood for durability. I chose poplar because the dimensions were right, and the grain is the closest to match the soft wood of the craft store wooden disks).

12)Rip 2 identical 11" long by 5/8" slats.

13)Rip 2 identical 11" long by 3/8" slats. Then cut off 2 inches off of each to make two (2) 9" long slats and two (2) 2" long slats.

14)On the 1" wide slats, you want to shoulder-cut a 1/4" wide by 1" long tenon on each end of the 4 slats you made. These will fit through the disks that make-up the top and bottom of your lantern. (See illustration).

15)On the 5/8" slats, you want to do perform this same task, but instead of centering the tennon in the center line of the tenon, you want it to be off-set on one side.

16)Once the tenons are cut, you need to cut a groove (approximately 1/16" wide and 1/4" deep) in the sides of your slats. I made a small jig on my dremel tool so I could hold it in a bench vice and used a wood-cutting saw blade that did the job. But you can do a similar job by putting your slats into a vice with a fine toothed back saw.and carefully saw a groove into each slat. The groove should go the full 9" length of each slat. Note that you need a groove on both sides of the 1" wide slats, but you only need a single groove on each of the 5/8" and 3/8" slats. On the 5/8" slats, you want the groove in the side opposite the side you put the tennon on. (See Illustration).

17)You can now use a dremel, knife or file to round off each of the 12 tenons so they are a nice round post that will fit into the 1/4" holes you've drilled. This will be one of the most laborious parts of the project but take your time as rushing this will only set you back. As you round off each tennon, try to dry fit it into any one of the holes in the disks. Continue this with all 12 of the tennons.

THE DOOR

18)At this point you can dry fit all of the tennoned slats and assemble the wooden parts of the lantern except for the door. Although this is not absolutely necessary, if you are hand-cutting all of the parts, I would suggest you dry fit at this point as you work on the door so you can ensure it's proper fit. (See illustration for order of slats)

19)Each of the 2" long by 3/8" wide slats you've made are for the top and bottom of the door. The ends of these (3/8" sides) you need to file or sand down to a 30 degree slant. This will make the edges of the door align with the narrower 5/8" tennons you have made that are supporting the door and making it look from a short distance that the lantern has six evenly spaced slats around it's perimeter.

20)You can glue together 3 of the door's sides. DO NOT FULLY ASSEMBLE THE DOOR. This is the one part of the project that requires glue and once you've glued the pieces together you will not be able to install the horn pane in the grooves of the door. Ensure that the grooves in each of the four door pieces is oriented to the center for installation of the horn pane. If you install the grooves facing outward, you will have to re-cut new door pieces.

20a)OPTIONAL: At this point, you can disassemble, stain and varnish/laquer your lantern's wooden pieces. Though it's not required for a properly functioning lantern, it will add a modicum of durability to the lantern and provide a bit of weather resistance, and really adds a finished presentation to your lantern.

21)Once staining and finish are complete and all the parts are dry, you may need to re-sand the tenons on your slats or file-out the holes of the disks where they mount, as they may have become gummed up by stain and laquer. At this point you can install all of the veritcal slats into the base plate. DO NOT BOTHER TO PUT THE TOP ON UNLESS YOU ARE JUST MAKING THIS INTO A NORMAL CANDLE LANTERN! (In which case, you are either done, or to add the finishing touches, skip to the horn pane section below).

LANTERN DISASSEMBLY

22)Disassemble the modern lantern you purchased using the screw driver and you may need a pair of needlenose pliers. The only pieces you are going to save are the U-tube bulb, the plastic bulb retention plate, the circuit board and the battery assembly pack (if it has one).

THE ELECTRICIAN IN YOU

23)You will want to solder or crimp a short length of wire (7 inches or so) to the tail of your on-off switch. Once of these connects to the + side of the battery, the other you will solder to the circuit board. (See diagram).

24)From the circuitboard, you will solder three (3) 9" long pieces of wire; one to each of the locations as shown on the detail photo of the circuit board; identified as "bulb post connections".

25)Each of these wires you will want to terminate (crimp or solder) with the female speed connector ends. Add heat-shrink tubing and heat with a lighter or heat gun to cover any exposed solder crimps or connectors.

26)As one of the last parts of your electical work; you want another wire 5" in length to go from the negative terminal connection on the circuit board. This wire will eventually be connected to the negative terminal of the battery pack (or lantern battery). Depending on the battery or terminal you have, you may want to terminate the wire with a small solderable alligator clip or ring post terminal. With the battery assembly that came with my lantern, I was simply able to wedge the wires of each lead under the metal contact plate. If I had to do it over, I would have soldered a terminal connector on so it would hold better. But this is entirely up to you.


BULB MOUNTING PLATE & INTERNAL ASSEMBLY

27)Since we are basically suspending a fluorescent U-tube in a wood and plastic box, you will need to add a stand-off so that the bulb's terminal posts can be reached and the wires connected. Take a 1" wide by 6" long piece of thin gauge steel or tin (20 or 22 ga is fine) and cut a slot into the center of it approximately 1/4" wide and 1 1/4" long. On either side of this slot, you want to drill a hole so that you can screw the #8" sheet metal screws through the plastic mounting plate you saved from the lantern disassembly. Bend the plate as shown in the diagram.

28)Install the on/off switch into the hole in the top. Use the nut that comes with the switch to secure it in place.

29)The mounting plate needs to be located on the underside of the top wooden disk, centering the bulb over the location of the on/off switch. Use 2 of the #8 sheet metal screws. Make sure so as not to cover any of the other holes you have drilled in the top with your mounting plate.

30)Connect each of the wires in the proper sequence of the bulb (wire 1 on the first teriminal, wire 2 on the second and 4th on the forth. Skip the third post on the bulb). When all is assembled and you connect the battery and turn-on the switch, if it does not work, simply remove the connector on the #2 bulb terminal and place it on the 3rd position).

31)Using the #10 bolt or threaded rod and your fender washers, mount the battery pack in the center of the wooden bottom disk.

32)At this point, you can install the top plate. Make sure to align the holes up of the top with the holes for the cord below. Carefully align the tenons with the holes around the perimeter of the top plate. Slowly work around the circumference pressing down until the plate is all the way on. Be careful not to force the top on.

33)Feed a cord through the holes you made for the suspension cord. This must feed

MAKING FAUX HORN PANES (OPTIONAL)

34)You do not have to make panes for the lantern, but they do hide the battery, wires and modern bulb and really finish the look of the lantern. To make the panes, you will need to cut some panels out of your 1/16" thick acrylic. This can be done with a few passes of a sharp razor blade and a straight edge. You will need five (5) panes that are 9" tall by 2 3/8" wide. And you will need one pane that is 8 1/2" tall by 2 1/8" wide

35)Sand one side of the acrylic panes with a fine grit sandpaper (200-300) grit. This will give the acrylic craft paints something to hold-on to.

36)Here you get to flex your artistic muscle and paint the sanded side of the plastic panes with acrylic craft paints. Use primarily white, but add streaks of black, brown and burnt sienna or whatever natural colors you think will make the plastic look like horn. It doesn't have to be neat, in fact you want streaks and a bit of blotchyness to make it look more organic. Allow the paint to dry for an amount of time as recommended by the manufacturer.

37)With the PAINTED SIDE FACING THE INSIDE OF THE LANTERN, install the panes by sliding one edge into one of the grooves in the vertical slat. Then carefully bow the pane outward by pressing from the inside of the lantern outward until you can slip the opposite edge of the pane into the slat on the opposing side. You want the smooth, unpainted side of the acrylic to be facing outward. Install the adjacent pane and work your way around the lantern until they are all installed.

37)Install the last (and smallest) horn pane in the grooves of the door. Finish assembling the door's frame. Glue and clamp the wooden pieces in place. Once the glue is dry, you can insall the door and hinges onto the lantern.

FINAL NOTES:
I glued the vertical slats into the bottom plate of my lanterns (never glue the top). This isn't necessary, but I don't feel that there will be a need for me to be able to remove the bottom plate, and I feel it might add some rigidity and stability to the lantern. In period, these tennons were probably foxed into position with a small wedge rather then glued. The top should always be free to be pulled apart in case you need to replace the bulb or repair a loose wire. The final weight will be around 3 lbs. (much heavier then a wooden lantern holding a candle), but because the cord simply passes through holes in the top and is fixed at the bottom, the weight of the lantern is fully suspended at the base. So there is no need to glue the top in place.

It is not mentioned in the instructions and was really an after thought, but shortly after completion of this lantern I added a handle of 3/4" diameter x 5" made from an oak dowel that I drilled a 1/4" hole through and finished to match the lantern. Though not necessary it makes it much more comfortable to carry than by holding it by the cord.

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