Gjøa 1872 by Harvey Golden - Roald Amundsen's Cutter built at Rosedahl, Norway

[Harvey Golden]

The aft windlass-- an iron structure-- is completed and installed.  Made from wood, paper, and watch and clock gears.  It was powered by the 3 h.p. Dan engine, hence the drive shaft projecting from the engine room skylight. A messenger chain ran forward from the port side to the pumps and forward windlass.  This assembly still needs the chain linking the lower shaft to the upper.  Some other details: scuppers as they appeared during the voyage, iron braces for the pinrail, and lastly a view of the whole as she sits today. 

Edited January 6 by Harvey Golden

[Srodbro]

Absolutely beautiful work on the windless!  I look forward to your interpretation of the mechanism at the pumps. 

[Harvey Golden]

2 hours ago, Srodbro said:

Absolutely beautiful work on the windless!  I look forward to your interpretation of the mechanism at the pumps. 

Thank you Steve!  I don't have the best info on the pumps and their arrangement, so it will indeed be an interpretation.  Photos of the Gjøa as she is today show her stripped down in this area (merely the stumps and no machinery), and the drawings I'm working from are a little thin or vague in this area.  Several historic images will be of great help, though. 

[Harvey Golden]

The mast's pinrail is completed, along with some of the attached machinery.  The winch heads are hand-carved from dowel ends-- no lathe in my shop. Quite a few other little things to do before stepping the mast, but it's just around the corner.  Next I'll tackle the pumps as best I can from limited information-- seems to be dearth of info as to how exactly they were set up; I don't even know what the big gear on the pinrail does or what it connects to, but photos show its presence. 

[wefalck]

I just had a quick look at my pictures of GJØA in the museum, but today this winch is not present on her. However, normally there would be a pinion that engages with the large cog-wheel in order to effect a reduction and mechanical advantage. This may engage via a dog-clutch.

[Harvey Golden]

3 hours ago, wefalck said:

I just had a quick look at my pictures of GJØA in the museum, but today this winch is not present on her. However, normally there would be a pinion that engages with the large cog-wheel in order to effect a reduction and mechanical advantage. This may engage via a dog-clutch.

I'll keep searching for old images-- I suppose at some point one must decide whether to put in the likely apparatus or leave unknowns omitted.   Too bad she's now stripped down so much in terms of deck machinery-- It does make sense as she's now cleared for visitors.  It looks like the aft winch has been moved back, and the galley has been re-positioned aft on the hatch to make it more accessible.  

[Harvey Golden]

Can anyone identify this bit of machinery on the Gjøa?  The image is from Roald Amundsen's Diaries, as issued by the Fram Museum, Oslo in 2017 (page 485).  It was taken at King William Island (the middle of his NW passage transit)-- note the hose running through the stern hawse pipe; perhaps for loading water?   Thank you!

[wefalck]

It’s kind of a vane pump, a single vane with two valve-flaps. It’s fed through a suction hose (kept open by a metal spiral). There is a suction cage at the end, as would be used e.g. by the fire-brigade.

[Srodbro]

Don’t know if you have these pics … they were included in my Model Shipways kit. 

In the upper pic, it looks to me that the upper shaft ( of all that equipment just ahead of the pumps) can be engaged-disengaged from the large gear on the lower shaft by sliding the open ended gear at the starboard end of the upper shaft. Also, it appears that the chain gear ( on the aft windless, just inboard of the portside barrel), the chain gear on portside of the assembly near the pumps, and the chain gear on the upper shaft of the forward windless, all three align. But, while I can imagine a drive chain running from the chain gear on the aft windless all the way forward to the main windless upper shaft, and a separate, shorter chain used to run from the aft windless to the portside chain gear on the shaft near the pumps; I can’t imagine how any power is transferred from the shafts driven by the chain to the two shafts just forward of the pumps. 

[wefalck]

It appears that the pump was driven from the lay-shaft in the foreground of the lower picture. This has chain-wheel for an ordinary chain just inside the spill-head. This chain presumably led to the frame just port of the pumps, where there was a similar chain-wheel on a shaft that seems to drive an excenter, which in turn seems to have driven the balancier of the pumps. However, that balancier and the piston-rods for the pumps are missing.

 

It is not very clear, but I think the cargo winch in front of the pumps was not driven from the lay-shaft, but traditionally via hand-cranks (missing). As I suggested in an earlier post, there was a sliding pinion that engaged the large wheel. In this way you had a two-speed winch: the upper spill-heads are driven directly from the cranks, while the lower spill-heads were driven through the gear-train, resulting in a mechanical advantage.

There are two ratchet-wheels on the whinch, one oriented clockwise and the other anti-clockwise, so that one could use the winch in both directions.

This kind of winch was universal on small cargo-vessels from the early decades of the 19th century on.

 

[Harvey Golden]

Dear Steve and Wefalck-- thank you both so much for the images and analysis of the Gjøa's machinery.  These images are exactly what I was hoping for-- they answer a million questions.  Looks like I missed the two smaller gears on the midship winch-- shouldn't be too hard to remedy.  Attached is the pump as shown in the historic image above.   Also shown: the exhaust pipe for the Dan motor (gray). 

[Srodbro]

Another pic from the kit is of the Dan engine. 

This view appears to be looking aft. At the fore end ( right of the pic) adjacent to the flywheel is a sheave that on the model drawings is identified as a chain drive … which would have a chain rising to a mate above, thence to the drive shaft that extends forward to the after most windless. Just guessing that the diameters of all the gears in the drive train to the pumps results in the pumps operating at about 60 strokes per minute ( the rate that might be reasonable for hand pumping?  I can’t imagine that rig stroking at a much higher rate), then, working back to the engine and seeing not many reductions thru the various gears and chain wheels, the engine RPM must have been very low, maybe 120 RPM. I wonder if the propeller, driven from the aft end of the engine, would have turned at this low RPM as well. 
 

This sketch is what I understand Wefalck describing at the pumps. 

 

[wefalck]

Yep, that's what I meant 👍🏻

 

These glow-head engines first developed in Denmark and the Netherlands for the fishing industry had to have long-strokes because the poor fuel they were designed to run on needed time to fully combust. Hence the low RPMs of around 50 to 150. They would literally run on any kind of liquid or semi-liquid hydrocarbons, such as rancid butter or seal-oil, though soot was a problem. One needed to start up the engine on something more flammable, such as alcohol or petroleum and then switch to the main fuel. The boats had two tanks for that purpose and sometime an additional tank on top of the engine to make semi-liquid fuels more liquid.

 

[Harvey Golden]

Here's the pump machinery underway, with the pump logs stepped with iron pivot bracket mounted (and corrected gearing on the winch). Thanks again for the photos Steve and Eberhart-- these have been a tremendous help.  (Looks like the photos that came with the kit were made during the WPA-HAMMS survey of '36-'37...)

-H

[Harvey Golden]

Well, it's back to the Gjøa again....  As I get close to the mast and rigging, I needed a good sturdy work stand for it-- one that will double as a display stand.  (The stand is 7/8" thick Southern Yellow Pine--a heavy and solid foundation).  The hull, as shown below, measures 27" long, and will be considerably longer once the stern davits and the bow sprit are on.  My workspace is only 45" long, hemmed in by a steel file cabinet, and a bookshelf, so this will be tight work.  I expect slow progress from now through the summer, but am aiming for an early '25 completion.  Welcome back!

 

[Keith Black]

 Well done, Harvey. Super nice!

[Reverend Colonel]

Big fan of this ship and this build. I have seen it in Oslo and have been an admirer ever since. The model looks great.

 

 

j

[KeithAug]

On 4/21/2024 at 11:37 PM, Harvey Golden said:

Well, it's back to the Gjøa again....

       The hull is looking lovely Harvey.

[Harvey Golden]

After a five-month break, it's time to work on the Gjøa's rigging.  First photo shows the current stage.  She's 3/8"=1', so the mast is just over 36" high when on the stand.  My work space is quite small, so I've moved the work to the dining rooms table. 

I've begun mounting the chain plates for the backstays and shrouds.  Also, I've mounted the davits after modifying their ends to have double-blocks. 

The shrouds are coming together nicely-- just glued now, but will be tied as well.  

 

 

[wefalck]

I couldn't check against my photographs, but the chain-plates look rather on the thin side to me.

[Harvey Golden]

53 minutes ago, wefalck said:

I couldn't check against my photographs, but the chain-plates look rather on the thin side to me.

They do . . . will double check the pics.  Thank you. 

 

-- They look about right, not knowing exactly how thick the original's are. They are rods and not strapping. They seem proportional to the shroud size I'm using. 

Edited November 7 by Harvey Golden
updated

[Harvey Golden]

Some progress, including blundering (as expected).  I had to re-do the deadeye attachments on the shroud lines, because I got a little ahead of my skis when following the instructions in Peterson's "Rigging."  The Gjöa's deadeyes are metal strapped to a solid thimble in the shroud-end instead of the usual way of running the shroud around the deadeye.  So . . . a fix and then proceeding with the rigging... compare with the above photo showing the incorrectly-made shroud ends. 

[wefalck]

Very good recovery.

 

I don't have Peterson's book, but believe that he based it on 18th and early 19th models in the Maritime Museum in Stockholm. There was no wire rigging at that time. By the end of the 19th century, after wire-rope had been introduced some 30 years earlier, rather than being taken around the deadeye, they were taken around solid thimbles. Normally, bottle-screws then would be used, but I gather they used a combination of old and new style on GJØA because bottle-screws can freeze solid, while with deadeyes and lanyards, one may still have a chance to tighten them. Also, they are easier to replace, when you don't have any supplies.