My Compass Thread

[iandvl]

I just collected my Mk III donor compass from PostNet. So perhaps I'll get the restoration of the Mk 3A finished over the weekend.

As I said in an earlier post - it's in rather shoddy shape. But that is fine - I am only after the compass card and grub screw - and they both look good. Those are the only parts I need from this one.

I will however, keep the leftovers in case I run into another Mk III again. I'd actually rather like to have a Mk III in my collection.




Peter - as you can see, the cover for the prism assembly is there as well as the screws. I'll see whether it fits on the M-73 when I strip it down this evening. I've got no idea how interchangeable parts are. Although they look very similar in terms of style and size etc, they are completely different models with about 40 years in between their "development". I say "development" because although the M-73 was introduced in 1973, they still manufacture them today. The Mk III was introduced in 1932 and production stopped sometime during, or just after the war years.

Strangely enough though, and this is what makes these compasses so confusing, is that the Mk 1 compass was introduced in 1966. This was a Mk III compass but converted to Mils. The differences in the Mk numbers and dates depend on whether they're roman or normal numbers. The Mk 3A is a bit of outlier in this regard - originally designated the Mk IIIAUST, it was shortened to Mk 3A.

Anyways, all these compasses were then superseded the M-71, M-72, M-73 and later the M-88, the last two being the only models still in production.

If the prism cover / screws do not fit, I believe I will be able to find spares for you. Spares are quite readily available for them.

[Peter Connan]

Thanks Ian

[iandvl]

Right, so more worky worky this weekend, but I am almost done now. After disassembling the donor compass, I decided to bastardise my restoration and use the Mk III compass card holder / oil well in the Mk 3A. Yes - this means it is no longer a Mk3A, but I was just impressed with the quality and condition of the oil well internals as opposed to the Mk 3A one. So I cleaned it up, did my doctoring with glow in the dark stuff and sealant and started filling it.

There is still a bubble in the oil. I'll remove it when I have time. I did not want to fill the oil well too much as I was not sure in what condition the gaskets were in. So I first wanted to check whether they gaskets help up.

Two things left to do.

1: I've got to tap a thread where I had to drill out one of the prism cover screws when I disassembled the thing a few weeks ago.
2: There is a design difference between the Mk III and Mk 3A in terms of the bezel grub screw. On the Mk3 A, the screw is internal to the compass and sticks out the side. The grub screw screws onto this. On the Mk III, the grub screw is machined with a thread which screws into the compass. In short, the grub screw will not work as it. I have ground away the grub screw thread, and will drill a suitable hole for it when I can. No idea where I am going to find a suitable tap for that, but I'll worry about that when I get there.

Some photos. Note that I had not refitted the prism cover or the crystal guard in the photo where it is open.




Edit: Oh - I forgot. There is a third thing I need to do. Francis Barker compasses have a rubber ring on the base. The restored one is missing this. I will need to source some suitable rubber, cut this to size and stick it on.

[iandvl]

A serious gem on the way... Hopefully...

Also, mods: please change the title to: my compass thread

[iandvl]

Right... So a new item is currently finding its way to me via courier.

This is quite a gem, as I said earlier.

It's an Aston & Mander compass. Aston & Mander generally manufactured draughting-related equipment, slide rules, navigation-related stuff, although they also manufactured some precision equipment - such as the compass I've just ordered.

It's a 1908 pocket / hunter compass. Case is nickel-plated brass. And something very interesting is that it has a Singer compass card. It is called a Singer compass card as it was designed by a Master Mariner - Samuel Singer. What made it unique was that he patented the design in 1861. It was valid for seven years and expired in 1868. Older variations of the Singer card will include the term "Singer Patented" on the actual card. The reason for the design of the card was because, being before the dates of "glow in the dark" type technology, he designed it with the purpose of being easier to see in the dark - with the Northern section of the card being in black and the Southern side white.

The lyre at due North on the compass card is a reference to the star, "Vega" - also known as "Lyra" and "the harp star". During the 1800's there were seven primary stars used for navigation, and Vega was one of those. Mariners apparently referred to it as the "Lucky Star".

In the photos, you will also clearly see the gem / crystal used for the pivot of the compass card. Whilst the F Barker compasses also use a crystal for this purpose, one cannot really see it without removing the compass card from the compass.

The condition appears to be pretty good and it even has its original bag / cover. It is missing the loop which is supposed to be on the knob at the top and there appears to be a bit of water damage to the compass card - which is not surprising considering its age. These compass cards were hand-painted, so I'm not going to do any restoration of this item when I receive it. It is just for the collection.

Pretty excited about this one. Some photos of the item. I'll post more when I receive it.

[iandvl]

So the item has arrived. Since I am more used to the bulkier military-spec compasses, I find it surprisingly small. It's super pretty though.

Apart from the stained compass card on the Southern side, it is in absolutely mint condition. I presume some of this is because it is still in it's original chamois baggie thing.

Despite not being dampened (ie: it is a "dry" compass) the mechanism is smooth and there are no "clunks" if you shake it slightly. If you try shaking a cheap "dry" compass you will know what I mean when I mention this.

The compass card will roll true at even strange angles - albeit not as impressive as a mil-spec one in terms of this. It is surprisingly forgiving in terms of the angle it is being held at.

Pity about the stain on the compass card, but I am not going to attempt any restoration on this piece. As I mentioned, it has a hand-painted compass card. Any attempt at restoring it will be an injustice and, considering its age (116 years old), some "damage" is to be expected. it is a nice complement to my collection and I am happy.

[iandvl]

I've been pretty quiet on this thread as work was hell shortly before leaving on my Bots trip, and then I was in Bots - which was awesome.

But I've acquired several new items for my collection.

First up - German pocket compass. I'm still battling to identify the manufacturer from the manufacturer mark. But research so far points at manufacture date some time between 1890 and 1902....

This arrived about a week before I headed for Bots...



Second up: An S. Mordan WWI war-issue vernier prismatic compass dated 1918. Beautiful and with original carry case. Similar to the FBarkers in that the compass card is mother of pearl. The two knobs on the side: one is the thumb-screw to lock the dial on a specific course and the other one is a transit lock to lock the compass card when the compass is closed.

There are two issues with this one - it is still mildly radioactive - I've tested... Older compasses used Radium 226 for illumination, which has a half-life of about 1600 years (I think). They stop emitting light after about 30 years, but the "rust brown" paint on the reticule is radium paint which is still radioactive. Does not pose a massive risk from just having the thing - but a lot of care needs to be taken when cleaning it off as it may affect you when ingested - either by inhalation or open wounds on hands. Also needs to be disposed of properly - but I have the contacts for that. The sapphire crystal is cracked and the radium needs to be removed. Otherwise - it is super pretty.




Third up: One I've been wanting to add to my collection for ages. A 1942 Francis Barker MkIII compass (not to be confused with the Mk3A I was restoring). Also original carry case. Two issues - I need to drain and refill to get rid of the bubbles, and I need to tighten up the screws on the cover tab thing. They are a little loose. Other than that, pristine.



Finally: This a fairly unique (and pristine) trough compass manufactured by JM Glauser. Also WWII issue, and probably around 1942 based on serial. Artillery trough compasses were designed to allow blunt end arty officers to align their maps, plotting charts etc on the plotting table - hence the fairly strange shape...

The little funny brass "button" on the top end of the box in the second picture is also a transit lock - so that the needle is locked in place when the lid is put on.




Anyways, I probably have an obsession with compasses. But I love them. I must start building a display case for all of these at some point, I guess.

[iandvl]

I said a while ago I've been battling with bubbles in the dampening fluid with the liquid-dampened compasses I have. Even when refilling, they still build up bubbles. A little bit of research indicates that white paraffin actually absorbs atmospheric air. And this had me a little stumped, but then I decided to build a vacuum chamber...

Bought a cheapy 12V automotive negative pressure pump, mounted it on a piece of plywood lying around in the garage. Put a pneumatic coupling on a mayonnaise jar, sealed with epoxy and bolted down nice and tight...






Stripped down all three of my liquid compasses yesterday, and voila... no more bubbles...

These are the Mk3A (top) and MkIII (bottom). I refilled the M73 as well (it had a few bubbles) but did not take photographs...



Cost: a vacuum pump for about R300. Rest of the stuff was lying around in the garage...

[iandvl]

I have two new items for the collection. One is super special...

First up - German Wehrmacht. It is marked CLK, but the compass itself was manufactured by Breithaupt. It is WWII issue as it has the Material- Prüfungsamt stamps on the back.

This will date back to prior to 1944 as from 1944 onwards these compasses were stamped with a big white capital "A" on the lid... It is my first German Wehrmacht compass. So I'm rather happy with it.




The second up is a treasure... This is an air ministry Type P.4 compass. These compasses date back from the mid 1930's and were used in various large aircraft - including Sunderlands and Lancasters. It needs a bit of work - dampening fluid etc. But I'll get around to that when I have time.

[walkabout]

Iandvl what do you think of this one? A guy was selling it at a local antique market but did not seem to know much about it.

[iandvl]

Heya. Mach III clone. Stanley was never really in the wartime compass game. This one has a serial number, which in most cases they would not have.

Luminiscent markings are incorrect. Looks like tritium and not radium as it would have been in the war years.

Does it have markings (as in directional markings) around the base of the compass - ie: not on the compass card itself ?

Also, is the thumb ring / clasp rounded or square cut ?

I would place it either as.

1: A fake Mach III.
2: A post war model.

It will be a good compass in any case, depending on what they want for it price wise. A lot better than the generic run of the mill compasses you can get. Alternatively, for spares. It does have a mother of pearl compass card and jewelled swivel. I can see this from the photos. You will need to get rid of the bubbles. But it looks good - despite not being war issue.

Edit: if you do not want it and the price is good, I would be interested purely in terms the compass card, crystals and prisms. Let me know.

Edit 1: Just noticed that it is graded in Mils. So much, much later. Possibly 60's / 70's. Still a Mach III clone though. Not M73.

Edit 2: After considering all of the above, and considering the 'Stanley London' stamp, on a Mach III in Mils, I am going to call fake. As I said, still probably a fairly good and accurate compass (test it) unlike the Stanley London Sine compasses, but I would not pay more than R300 for it.

Edit 3: What were they asking ?

[iandvl]

Final note on this.

It is possibly a knock off of a Mk1 compass, which dates from 1966 and was a Mach III compass converted to Mils.

I say knock off, because Stanley London would not have manufactured those and the serial number would be incorrect even if they did.

Edit : I could be a Stanley G150 which was apparently stamped Stanley London and is considered fairly iconic by the British Army and produced between the 70's and 99. But the serial number is incorrect and there is no war department or radiation stamp on it.

So in my honest opinion, still a kock off. Unless it was a precursor to the G150 (ie: if it has directions stamped on the sides of the compass).

[walkabout]

Thank you for you detailed reply iandvl. Sjoe, you know your way around (without!) a compass!

He wanted R650 for it, but just with me looking he already said he "can give it to me for R500". This being "Durban & all'. Having said that I did not feel he was a swindler, merely a reseller, and I also did not get the impression he knew too much about the product - it was one of probably 40 different things he was reselling.

If you are interested, I can take more detailed photos for you next time the market is held, it's a monthly thing I think; or just tell me what to look for or take photos of for you.

I want to get a decent working compass for myself, to have in the car on trips, just for in case, for fun, but also to teach my daughter a bit. I never know whether the cheapies in the shops are worth it for that though.

Anyway, I have derailed your thread enough, just thought it might also be of interest to you.

[walkabout]

Having read your last 2 posts now again I see you gave me quite a few clues - I will have a more detailed look next time and report back.

[iandvl]

Having read your last 2 posts now again I see you gave me quite a few clues - I will have a more detailed look next time and report back.

At ZAR500 (if that is what was said), it will still be a better compass than you can will be able to acquire elsewhere. Anywhere...

The only issue will be the mils thing. Not everybody gets it.