Mark's Monitor Build

[Richard Hed]

The original Monitor drawings apparently show more than one engine configuration?, with one configuration having vertical cylinders (if I am looking at that drawing correctly).
I guess it is understandable that steam engine design of the era was in a state of flux, and there was no concensus about exactly what the best engine design/layout was.
Some of the Monitor's dimensions were driven by the very low profile of the Monitor hull, and the need to keep the engine below the deck of the boat.
The quality of the original Monitor drawings is much better than the quality of the original Mississippi gunboat drawings by Charles Copeland.

I would guess that Rich Carlsedt has compared the original Monitor engine drawings to the actual recovered Monitor engine, and he would have a better idea on the actual "as-built" design of the Monitor engine.


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You are saying that there are original drawings somewhere? I thot they were destroyed or bug eaten or something.

 

[GreenTwin]

Rich Carlsedt will have to weigh in on the original drawings, because I am not sure how complete they are, and I see different variations for the engine.

But I have a set of (some?) of the original drawings for the Monitor engine, and they are pretty good drawings in my opinion, even if a bit light in contrast/visibility.

Unfortunately I don't recall the source for the original drawings unfortunately, but I have a digital copy of them.
The source may be the museum that is restoring the original recovered Monitor engine?

Rich knows all these things; perhaps he will fill us in.

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[kvom]

Interesting to see the cutaway view. I'd always assumed there was one piston and a single rod. So it appears that each piston only sees stem from the outer side to push it towards the center, and that it's retracted by the external crank.

 

[dnalot]

So it appears that each piston only sees stem from the outer side to push it towards the center

The two pistons have steam pressure applied to both sides

Mark T

 

[GreenTwin]

Yes, it is two pistons, both double-acting.
There is I think a cylinder head bolted in place in the center, or perhaps cast in place.

It is quite a tricky little design.
I think it falls into the trunk-engine category?
Rich is the one who can answer all these questions.
He knows this engine like the back of his hand.

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[dnalot]

It is quite a tricky little design.

The tricky part is the steam chest valves. There are 2 in each chest. One works like what you find in most steam engines. The second is timed to take pressure off the first valve when it is in motion. Saving that for last.

Mark T

 

[dnalot]

You are saying that there are original drawings somewhere? I thot they were destroyed or bug eaten or something.

I think they were found recently at Mar A-Lago

Mark T

 

[Richard Hed]

I think they were found recently at Mar A-Lago

Mark T

Are they available to download?

 

[GreenTwin]

The tricky part is the steam chest valves. There are 2 in each chest. One works like what you find in most steam engines. The second is timed to take pressure off the first valve when it is in motion. Saving that for last.

Mark T

I think the correct term is riding cutoff, when you have one valve riding on top of another.

Early cutoff gives far more efficiency of operation over just a standard D-valve, which is limited in how quickly it can cut off the steam after the start of admission.

The idea is to admit steam into the cylinder at or near TDC, and then cut off the steam at some point early in the piston stroke, and thus use the energy available in the expanding steam, as opposed to cutting off the steam late in the stroke.

A late cutoff produces a lot of torque, but is wasteful of energy.
Most steam locomotives had adjustable valve gear, so that when trying to get a train moving initially, the gear could be adjusted for a very late cutoff at or near the end of the stroke, and then once the train was moving, the gear adjusted to give a much earlier cutoff, since maximum torque is not needed when the train is moving.

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[GreenTwin]

I downloaded Rich Carlstedt's drawings a while back, and at a quick glance, they appear to be very high quality, like everything Rich does.
The Monitor engine is so complex that I have not had time to study Rich's drawings in detail.
I understand the Monitor's basic geometry and valve function, but that is the limit of my understanding of the many parts and pieces.
I do understand how trunk engines operate, in general.

Rich posted a link to some (all?) of the original Monitor drawings from the 1800's and I have downloaded quite a few of those.
I had to go back and find that link again tonight, since I had forgotten where it was.

I have not had time to research the original drawings either, to find out how complete they are, and compare then with Rich's drawings.
I suspect that Rich's drawings are very accurate, because that is how he works.

Here is the link to the original Monitor drawings.
A bit tedious to access and sort through, but thank goodness they have been digitized and posted.

https://rucore.libraries.rutgers.edu/search/results/?rtype[]=&key=root&query=monitor+ironclad

It is a bit of an art to interpret old drawings, and drawings in general.
I have gotten a lot of practice by working on a 3D model for the Mississippi side lever engine, from the original 1840 drawings.
The Mississippi original drawings are poor in quality, and contain errors, so that adds to the challenge.
Screencap of the Mississippi 3D model to date.
It is extremely tedious to 3D model an old engine accurately, and exactly as it was built originally.
There are so many subtle, tiny, but critical details in engine designs.
You basically have to start from the inside, and slowly work outwards, modeling one piece at a time, and making sure it mates correctly with any connecting parts.

As I undertand it, Rich Carlstedt has many years invested in his Monitor 3D model and associated 2D drawings, and I fully understand how long it takes to do that accurately.

 

[Robert Ritchie]

Very interesting, well written and explained clearly, 2d 3d cad drawing video great job! thank you for all the time and effort that went into this build and then sharing your talent with us, well done!

 

[Richard Carlstedt]

Thanks to all for the kind comments
Green twin has been very accurate in his responses and you might say he has saved me many keystrokes : )
Getting accurate information on the Monitor has now amounted to 30 years of research and
let me say, seeing a drawing does not make it right. I found large amounts of incorrect information both in written format or sketches and drawings. To separate the wheat from the chafe was a yeoman's job. I am currently writing a book describing the engine (using My book of drawings for reference ) and will include the errors " I " believe that are prevalent.
The drawings that Green Twin mentions are available on the New Jersey Digital highway website, but be aware that of the 80+ drawings posted , it is more than Monitor's engine. The engine drawings that are beneficial number perhaps 12-15 and most are not dimensioned. One part on 3 separate drawings has 3 different lengths as an example of error. but I don't think it was error as much as being the same part for different engines and the drawings were classified as a " Monitor" drawing
The engine should have been a 2 cylinder engine like the predecessors were, but Ericsson needed
to narrow down the engine's width because of the beam of the ship and used a common casting with a "center-head" separating the steam chambers . The valve chests ( 4) are a masterpiece of engineering, having the cutoff valve in the outside chest and the main valve chest captured between the cylinder and cutoff and driven by 4 eccentrics with the control eccentrics ( F & R) being on the outside ( ! ) with Ericsson's "Phase Changing " reversing gear.
My Original 2 D drawing ( AutoCad 95 ) was the size of a football field as I drew the engine many many times in various configurations on the same field. ( 30-40 engines plus many parts ?)
For example, I spent 6 months on one dimension alone, the C/L distance between the cutoff and main valve chest. It was either 10 1/4" or 10 " and I kept redrawing the engine to find what made all the parts fit. I settled on 10.25"
The real KEY to solving the scale to use was the Navy overhaul report of Oct, 1862
where they recorded the size of the steam ports as 4" x 16" , and that alone was worth gold as
the general layout drawing of the engine had no dimensions. So the drawings that i got from a book were all measured with a 10 power pocket comparitor and scaled to 5 decimal places.
in some cases I had to do a spreadsheet with what fits and what if's ...to get the dim.
I have to say, my Dims have held up quite well as they discover the real engine during restoration.
The highlight occurred maybe 10 years ago ( model was finished) and the museum showed me a "new" drawing they had just obtained from shipyard sources and it showed----10-1/4" valve rod spacing...and I smiled
The years of research required travel and there were only 4 Monitor models in existance to speak of before I built my replica.
The Smithsonian has Ericsson's 1858 patent model (no valve gear) (Not Monitor )
The British Science Museum (Kensington) had the actual Patent Model (1862) ( No Valve Gear )
New England model builder Ray HasBrouck built a non scale model ( magnificent friend !)
Mariners Museum Builder Bernard Denny built a closer model from magazine info ( also Friend )
Ray and Bernie helped point me in the right direction even though they had no drawings as they had scratched built their engines . Bernnie's model is displayed at the museum and both of Green twins pictures are of that model.
Hope this helps answer some questions.
Rich

 

[Richard Carlstedt]

Here is an example of my work. I spent maybe 5-6 weeks on this drawing alone
and from that I will show you what that means
Now I only had a 5 x 7 book Zeroxed print to work with , but the Digital highway shows it full size
and much greater detail but look at it anyway

https://rucore.libraries.rutgers.edu/rutgers-lib/42264/PDF/1/play/

Now here is what I saw in that picture
and the second picture shows what it means
The Purple images are added to the information derived from the above drawing
As an explanation "Why" was this drawing made this way.. it is simple. the Civil War
was going on and paper was being put to maximum use and it was also some
" engineering concepts" being drawn --Ericsson's sketchpad so to speak

Rich

You can see my notes to myself in the last picture at the bottom
I had so much data on that football field drawing that I wrote notes all over the place to keep track of info . The above two pictures were small images on that drawing

The two circles represent the Quadrant gear and the pinion gear ( 2:1 ratio) in the first drawing and then shown in purple
Rich

 

[Steamchick]

Hi Rich. It seems that you have done an enormous amount of work deriving the history of this (Unique?) and historic engine. Trunk engines were relatively common at the time - or so I understand? (British naval use, Brunel and others had them?) but the head-to-head configuration - with bell-cranks to shafts to conrods to the drive shaft is a variation that is rarely seen, I think? (Necessary for "packaging" in the Monitor!).
And I didn't know about the special valve gear before reading this thread. - I must read more...
THANKYOU!
K2

 

[GreenTwin]

I finally got around to unzipping all of Rich's drawings, and merging them into one PDF file.
Mother of gosh, that is a lot of drawings !!!!

What a phenomenal amount of work that went into that 3D model and 2D drawing set.
I would classifiy that as a "ludicrous" amount of effort, and I am shocked that anyone could pull that off.

Some comparisions beween the 3D model I am making for the Mississippi side lever engine and the Monitor engine:

1. The Mississippi engine was designed and built around 1840.
It looks like there were some pretty dramatic advances in steam engine design from 1840 to 1861.

2. The Mississippi engine is a big sprawling Cornish-style (check me on that) engine, and luckily there are quite a few examples on paper and physically available for study.
Compared to the Mississippi engine, the Monitor engine is very small and very compact, with a tremendous amount of complexity compressed into a very small area.
The gigantic size of most of the Mississippi engine parts, and generous spacing, makes it seem infinitely easier to 3D model than what I would imagine a 3D model of the Monitor would entail.

3. The Mississippi engine drawings are very poor, and apparently this was Charles Copeland's first attempt at a steam engine design, because there are some real gaffs in his drawings. I did find a set of drawings for an 1840 French-designed side lever marine engine (very close in design to Copeland's Mississippi engine), and the contrast between the French drawings and Copeland's drawings is like night and day. The French drawings were obviously designed by a very seasoned professional engineer and professional drafting person, and they are excellent drawings even by today's standards.

4. I typically model engines that don't have very many parts, and generally one cylinder designs.
The reson for this is practical, given the time it takes to create an accurate 3D model, and also to align my building skills with model complexity.

Rich is on a phenomenal building skill level, and all I can say is his skills are shocking.

I have had the pleasure of speaking with Rich on two occasions, and I recall discussing what it takes to build a Monitor like Rich's.
I told Rich "It is the persistance".
Rich said "What about the skill?".
I said "Well, yes, that too, but many folks who had the required skill level may not persist through such a build".
A person has to have the skills, drive, determination, and persistance to carry on when the build is going well, and more importantly carry on when the build is not going well.

It is one thing to build a model engine, and a whole different thing to create an enormous accurate drawing set for the Monitor.
The combination of engine build and accurate drawings is so over the top of anything I have seen that I really don't know how to give it justice.

And not to forget this is "Mark's Monitor" thread, what a superb job Mark is doing with this very complex engine.
I have done quite a bit of casting work, and Mark's castings look so very nice.
I can appreciate how difficult it is to make such nice castings.

I am in awe of this build thread, and everyone who is involved with it; that is all I can say.

.

 

[johnmcc69]

Nice work Mark! I love the finish!

Keep on going with it!

John

 

[Richard Carlstedt]

Hi Rich. It seems that you have done an enormous amount of work deriving the history of this (Unique?) and historic engine. Trunk engines were relatively common at the time - or so I understand? (British naval use, Brunel and others had them?) but the head-to-head configuration - with bell-cranks to shafts to conrods to the drive shaft is a variation that is rarely seen, I think? (Necessary for "packaging" in the Monitor!).
And I didn't know about the special valve gear before reading this thread. - I must read more...
THANKYOU!
K2

Yes, It is a rare engine of sorts (for a trunk) and unique and I cannot find any other engines built like Ericsson's design- It is actually a "Half Trunk" since it is only on one side of the piston and is unlike many other half trunks, which are usually oscillating engines. Monitor was the first Vibrating Lever Half Trunk engine ( 40 x 22 Bore/Stroke) , and they built 10 more slightly modified and then went to 48 x 24 for another nine engines so a total of 20 engines were built to that design. Unfortunately some folks refer to the Monitor engine as a 'Side lever engine" which is completely incorrect. Look at Green Twins Drawing in post 70 for what is a side lever engine design. World of difference !
I am very pleased that outstanding models of Ericsson's design have been made by both builders Geoff and Mark.
They truly reflect the complicated construction and operation of this engine and committed to the details to show that ...Bravo !
Rich

 

[Richard Hed]

Does anyone know if John Ericsson wrote anything about his engines and work?

 

[GreenTwin]

The book that Rich refers to "Drawings of the U.S.S. Monitor" by Earnest Peterkin has an extensive list of drawings that have been found in various places for the Monitor.

It appears that Ericsson envisioned a prototype called a "Sub Aquatic Weapon" in 1826, which he tried to market to several countries.
I aways suspected that while the Monitor may have been constructed in 90 days (so they say), the design of this gunboat materialized over many years, and was refined as time progressed.

Each drawing has a brief description of where the author thinks the drawing originated, and who he thought drew it.

The book describes how Ericsson requested that upon his death, all of his papers should be destroyed.
I assume this means he wanted the Monitor drawings destroyed too, but I am not positive.
Luckily someone rescued Ericsson's papers after his death, so they were not destroyed.

There were some in the Navy that harshly criticized Ericsson, and did not consider his boat/ship designs up to navy standards.
Others noted that the Monitor hull was not watertight, and so the concerns did play out, and the Monitor sank, I think during a storm while being towed in the ocean.

Given the demanding circumstances of the time, I think the extremely fast construction of the Monitor, and its ultimate function in battle were significant. There is much debate about who won the Monitor/Virginia battle. It is often decribed as a draw, but it did appear to stop the Virginia from inflicting further damage to the Union wood ships.

The drawings in Peterkin's book appear to be monochrome, but some of the original Monitor drawings I downloaded from the Rutger's Library (link above) are in color, which is really cool to see, and are works of art in my opinion.

Peterkin's book contains some coorespondence between some Navy folks and Ericsson, concerning things such as how stable the Monitor was, etc.
Apparently there was concern about the weight of the turret, but Ericsson proved that the Monitor stability was more than adequate even with the massive turret sitting on top.

I also read a book about the actual battle, and I forget the title, but is a fascinating story for sure.
As I recall, the captain of the Monitor was in the forward lookout position, and it took a direct hit, blinding him, but not killing him.
I thought my job was tough.

Another fellow inside the turret was injured when a shell/cannon ball struck the turret, as this fellow was leaning against the metal armor.
I guess the shock wave or the deflection of the metal was sufficient for injury of anyone toughing the turret.
The men inside of the turret that were not touching the sides were not injured.

You can download a PDF copy of the book "Drawings of the U.S.S. Monitor" by Earnest Peterkin at this link:

https://archive.org/details/drawingsofussmon00pete/page/n3/mode/2up
I suspect that John Ericsson must have written about his work, or at least we can learn a lot from his coorespondence with many people.

There is so much history wrapped up in this engine and boat, both from a technical standpoint, and from the standpoint of the human side of the navy men that operated it.

Edit:
I think the book above also mentions that Ericsson already had a patent for an engine design that is very similar to what was used in the Monitor.
This reinforces the idea that the Monitor boat and engine were the result of many years of Ericsson designing and refining both.
I am not sure how they could make patterns, cast the engine parts, and machine the engine parts in 90 days, much less install all of the equipment in the boat, but that is the story that is told (not sure I believe the 90 day thing, but I suppose it could be possible).

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[Richard Carlstedt]

Does anyone know if John Ericsson wrote anything about his engines and work?

Yes Richard there is a book. you can find the digital version here
https://archive.org/details/contributionsce00eric/page/n39/mode/2upIt is sort of a autobiography of his accomplishments
I have a thousand comments about John Ericsson but am tied up now, so will respond more
comprehensively in a short time
Rich