Compass Project -- STEP 1

[moribundman]

The insanity continues.

I drilled three holes (1 mm diamter) into the compass housing:

A close-up:

That's a 1.2 mm watchmaker's tap. I didn't use a vise. the tap cuts through alu without any effort:

A close-up:

 

[moribundman]

Alright, just for my own amusement, here's more progress:

Remember the bottom cover that I made? This one:

Well, this is how the back of the cover, which faces the inside of the compass housing looks with the Makrolon lens in place. The edges were sealed with epoxy resin, the lens was masked and the inside was painted flat black (Just for kicks, after all this side can't be seen once the compass is assembled. Call me pedantic...). The lens can be replaced should it get scratched. However, I will apply a precisely cut piece of cling screen protector to the outside of the lens, so I probably won't have to replace the lens ever:

I had to made a new pointer, because the original pointer was too short. The pointer was part of the hinge assembly. I made the new pointer from sheet brass. Here is a picture that shows you how small this part is:

The pointer fits in the vertical slot in the aluminum housing:

I have replaced the rivet that used to hold the mirror in place with my own fastener, which I fabricated from 1/16" brass tubing (drilled with an 0.96 mm drill), 4 brass 00-80 size washers, and 2 brass nails, each 1 mm thick. All parts are press-fit. The mirror's hinged tabs exert enough pressure for the mirror to stay up. I added two inner brass washers to prevent wear on the aluminum parts. The outer brass washers prevent reduce wear on the nails' heads, which otherwise would rub against steel.

In the two pictures below you can also see the pointer. The pointer had a little bit vertical play, which resulted in the pointer getting too close to the compass bezel (not shown). I eliminated vertical play by drilling a 1 mm hole right under the bottom of the pointer. I tapped the hole and a countersunk a 00-90 size brass screw prevents now vertical play. There was no lateral play to begin with, since the pointer's width was a perfect match to the slot's width.

Here is a picture of the temporarily assembled compass. Some screws and a few details are still missing, but you can see how the whole device will look in the end.

The Super-LumiNova is insanely bright. For 10 to 15 minutes it is brighter than luminescent tritium markings. After 12 hours, the luminescence is sufficient to serve its purpose. The large arrow is made from a plastic that contains a luminescent (but non-radioactive -- I checked) substance. Despite the age of the compass (40 to 50 years old), the lume works still fine. The green color of the arrow does not match the Super-LumiNova markings, but I don't care about that. In the picture the Super-LumiNova markings appear more cyan than they really are.

I guess I'll post a few more pictures of the compass from all sides once it's finished. Okay, who do I hear snoring? WAKE UP!

 

[moribundman]

I started the project in late August and worked on it intermittently. I will finish it today. So the project took me just about 2-1/2 months to complete.

- disassembled the original compass, cleaned and sanded the alu parts

- made some sketches based on measurements

- made styrene templates for dial

- cut the dial from sheet alu

- cut an aluminum spacer from alu

- made an adaptor from styrene, made a mold of it, cast the adaptor in urethane resin

- made a locking ring out of brass that holds the compass capsule securely fastened to the bezel adaptor (compass capsule easily replaceable)

- drilled and tapped more holes than you'd expect

- bolted stuff together with mostly 00-90 brass screws, nuts, and washers

- got some Super-LumiNova powder, which I mixed with clear urethane resin to make waterproof luminescent markers

- made a bottom cover out of a spare alu bezel, a "donut" cut from sheet alu, a lens cut from Makrolon, all glued and epoxied together

- fabricated and installed a little cover that allows access through the bottom cover to the declination adjustment screw

- drilled and tapped another bunch of holes into the compass housing and into the bottom cover

- fabricated a new pointer from sheet brass

- fabricated a new fastener for the hinge

- final assembly

Oof...

 

[Oldmoparguy1]

Super excellent!!

 

[moribundman]

Do you prefer a fruit basket or cash?

 

[tom slick]

do you have a matching secret decoder ring?

that is a very nice project and thank you for great detailed photos.

great solution for the pivot pin setup.

 

[moribundman]

A decoder ring would make it too easy.

I usually work on some project to keep me busy during my insomnia attacks. For once I wanted to chronicle a project, mostly because I do it all in a sleepy haze and don't remember to well the next day. I'm basically sleepwalking between the fridge and my work bench.

The pictures pose no challenge, because I have a light tent set up permanently.

I hope the pivot pin will work well for a long time. If not, it's easily replaced. I actually made a spare pin that I will keep in the compass case.

 

[tom slick]

I knew you live in a photo booth!!

 

[moribundman]

It's a photo booth and so much more.

 

[moribundman]

After a lengthy and deserved hiatus from looking at my compass project, I have decided to terrorize you all with the final result. I'll also explain some of the features this 40 to 50 year old, but modernized compass has.

Compass closed:

Compass open. At the bottom of the right rear corner, not the little "claw" that is in locked in the upright position. It can swivel:

The compass closed, standing upright. You are looking at the bottom that I fabricated. The tiny cover allows access to the declination adjustment screw:

The compass with its original leather case. In the case fits also the included, foldable ruler, which can be used for measuring distances and object sizes by holding the ruler at 50 cm distance from your eyes. The ruler can also be attached to the two "claws" at the back of the compass, which aids in determining bearings. On the string is the declination adjustment tool (screwdriver):

This is not exactly how you hold the compass for sighting, but taking a picture with the other hand, I wasn't able to hold the compass properly.

Anyway, you see the sighting slot in the upright cover. Each side of the cover has a slot. Each slot has a horizontal wire, which allows leveling the compass. After sighting your target (Uh, mountain peak, old goat, pirates, Pablo's rock, etc), you turn the compass bezel until north is boxed. You can then read the bearing ("where you want to go") off the dial. You do this of course by looking in the mirror:

This is the original clinometer. It measures in degree and mil ("Strich"). Mil are of course used to calculate target size or object distance:

The small red line with the red indicator dot is the fluid dampened clinometer that is inside the compass that I installed in the old housing. In this case it shows a 20° angle (incline).

The included ruler may be attached to the back of the compass to extend the base:

Normally, if you use a compass with a map, you have to orient the map towards north. With this compass you do not have to do that! The map may point any way. How does it work? Let's say you are at point A and want to go to point B. Place the compass on the map and orient its base to point from A to B. Now turn the compass bezel until the black line in the compass is parallel to either text on the map or to a line of latitude (L - thin red line and yellow line). Now you can read the bearing that will take you to point B off the dial. In this case your bearing is 334°:

I'm afraid this whole thing isn't over just yet. This thread contains so far about 54 pictures.

 

[firemachine69]

That's awesome.


Can I ask about that paint, cost, source, and time to actually receive it from the dealer? Might be just the ticket for the front sight on my Beretta Storm.

 

[tom slick]

You may not want to test your compass right there, Parkfield has lots of earthquakes and changing geomagnetism

I didn't know what all the extras on a compass did, thanks for the update.

 

[moribundman]

Originally Posted By: firemachine69
That's awesome.


Can I ask about that paint, cost, source, and time to actually receive it from the dealer? Might be just the ticket for the front sight on my Beretta Storm.

The manufacturer of Super-Luminova is Tritec in Switzerland. Google "rctritec." They will likely sell only large quantities and none at all to private entities. You have other options:

Otto Frei & Jules Borel (jewelry supplies) in San Francisco (google "ottofrei") sell AF-Luminova (Alfex brand?) pigments in various colors in small refill bottles for $16 each. You can buy a single bottle. The page with the pigments appears unlisted (I don't know why) on their Web site, but I will send you the correct link in a PM. I am not sure if these pigments match the quality of the Tritec pigments.

To find paint and pigments similar to Super-Luminova, google "glowinc" and "readysetglo." Both online vendors carry a line of paint and pigments.

On a gun sight you may want to use tritium markers (vials filled with H-3, hydrogen-3 gas), because they don't rely on being "charged" with light. While the import of tritium is regulated, the sale of small quantities of tritium is not. You "may" be able to get tritium vials from an official importer only.

 

[moribundman]

Originally Posted By: tom slick
You may not want to test your compass right there, Parkfield has lots of earthquakes and changing geomagnetism

I didn't know what all the extras on a compass did, thanks for the update.


I'll navigate around the area marked "Hic svnt dracones."

There are several types of small compasses. Most have specific uses. A hiking compass is a bit different from a mountaineering compass, but very different from a surveyor's transit, while a military marching compass is different from an artillery compass. There are baseplate, sighting, and lensatic compasses. Some compasses have mirrors, lenses, or prisms. Which compass is the best depends on the intended use. Some compasses can meet several requirements, but are often a design compromise.

My modified and updated Bézard can be used pretty well on a map. It is fully suitable for hiking and even navigating while running. It is very usable for sighting and for determining angles, object sizes, and distances. Since the Recta (=Silva) capsule that I installed has a global needle, this compass will work in both hemispheres.

 

[Shannow]

Well there's something new learned today...

Obvious when you see it spelled out.

 

[Gary Allan]

Standard issue for any operative on remote recon for Dr. Evil's next hidden base. In today's budget environment, the most successful freelance operatives are also their own "Q".