Monitor V - Yes, another one!

[sshire]

Monitor V - Yes, another one!

“At no great distance from the Minnesota lay the strangest-looking craft I ever saw. It was a platform of iron, so nearly on a level with the water that the swash of the waves broke over it, under the impulse of a very moderate breeze; and on this platform was raised a circular structure, likewise of iron, and rather broad and capacious, but of no great height. It could not be called a vessel at all; it was a machine—and I have seen one of somewhat similar appearance employed in cleaning out the docks; or, for lack of a better similitude, it looked like a gigantic rat-trap. It was ugly, questionable, suspicious, evidently mischievous—nay, I will allow myself to call it devilish; for this was the new war-fiend, destined, along with others of the same breed, to annihilate whole navies and batter down old supremacies. The wooden walls of Old England cease to exist, and a whole history of naval renown reaches its period, now that the Monitor comes smoking into view; while the billows dash over what seems her deck, and storms bury even her turret in green water, as she burrows and snorts along, oftener under the surface than above. The singularity of the object has betrayed me into a more ambitious vein of description than I often indulge; and, after all, I might as well have contented myself with simply saying that she looked very queer.”

Nathaniel Hawthorne



The ship, designed by John Ericsson, was powered by a single-cylinder horizontal vibrating-lever steam engine, also designed by Ericsson, which drove a 9-foot (2.7 m) propeller, whose shaft was nine inches in diameter. The engine used steam generated by two horizontal fire-tube boilers at a maximum pressure of 40 psi (276 kPa; 3 kgf/cm2). The 320-indicated-horsepower (240 kW) engine was designed to give the ship a top speed of 8 knots (15 km/h; 9.2 mph), but Monitor was 1–2 knots (1.9–3.7 km/h; 1.2–2.3 mph) slower in service. The engine had a bore of 36 inches (914 mm) and a stroke of 22 inches (559 mm). The ship carried 100 long tons (100 t) of coal. Ventilation for the vessel was supplied by two centrifugal blowers near the stern, each of which was powered by 6-horsepower (4.5 kW) steam engine. One fan circulated air throughout the ship, but the other one forced air through the boilers, which depended on this forced draught. Leather belts connected the blowers to their engines and they would stretch when wet, often disabling the fans and boilers. The ship's pumps were steam operated and water would accumulate in the ship if the pumps could not get enough steam to work.

A most amazing evening in the hotel lobby at Cabin Fever. Rich Carlstedt explained, in detail, his exquisite build of the Monitor engine. After that, there was nothing for it but to build one from Julius’ excellent drawings.

I’ve apparently been trumped by the three current builds on the forum. That turned out to be a good thing as I’ve noted setups, differences between the metric and imperial drawings and general construction details.

After checking the stock on hand, metal was ordered and off we go.



Inner and Outer Base Frames





First, a rough indication of where to bandsaw the corners away.




Fortunately, before I cut right into the corner, I remembered that there is a .25” radius. That was marked out. First Bozo move thwarted!



My intention was to make a fixture to hold all four plates and do all machining, drilling and boring one time rather than four.

Note the precise fixture layout.



With holes drilled and reamed to fit over the dowel pins, the fixture was indicated and metal removal commenced.





Holes drilled and reamed and slots slotted with a center cutting end mill.







Next,the .75” holes were drilled and bored.



And, the “window” openings were removed.



The cylinder mounting plate and rear frame spacer plate  are the same size.
Clamped together and face milled to dimension.



Since the QC Department acquired a .0001 Johansson Mikrokator at NAMES, it was used to compare the widths of the parts. It was zeroed with a 1" gauge block.



Part 1; Close Enuf



Part 2; .0002 high.



Looking at Julius’ drawings, I realized that the cylinder mounting plate and rear frame spacer plate have a total 24 4-40 tapped holes. Add the 16 holes on the ends of the Outrigger base frame, we now have 40 holes to tap.

Form tap, Tapmatic head to the rescue.

<a href="https://www.youtube.com/watch?v=ZCdLqUZEtWs" target="_blank">http://www.youtube.com/watch?v=ZCdLqUZEtWs</a>

The Outrigger Base Frame has 4 - .125 x .5 deep slots. After 2 passes with a .125 end mill, I knew this was going to take way too long.  I broke out the heavy artillery. A Malco 5” x .125 wide slitting saw.



I’d been thinking about a very rigid setup for the cuts. Added a Kant Twist clamp to back up the part so it cannot pivot away from the blade. 80 RPM, Bridgeport in back gear and the Micro-Drop was moved right at the cut after this pic.





One pass; full .5” depth (per Malco's advice) and done.






The Outrigger Top Plate is just 10, 4-40 clearance holes.
I did model the part in Inventor and set the center (Y) and the left edge (X) as origins. Easier to machine.



Progress to date. Stay tuned.

[b.lindsey]

You are off to an amazing start there Stan!!  Looking good already and thanks for adding IV to the build log, that will help keep them all separated

Bill

[crueby]

Great start on the engine! Please tell me this was more than one days work!?

 

Though isn't this one the 5th monitor build? Hard to keep track!

[mnay]

Stan,
great start.   Were the plans posted somewhere on the forum for the monitor engine?
I know he has posted quite a few plans.
Thanks
Mike

[b.lindsey]

By my count it will be #5. Stan, let me know if you want me to go back and change the subject lines to V instead of IV.

Bill

[Don1966]

Stan that's awesome buddy, your sure off to a good start.........


  Don

[vcutajar]

Great start Stan.  Will be keeping tabs on your build also.

Vince

[sshire]

Thanks, guys.
This was a week to this point.
Bill
Please change subject line. I must have missed one unless Zee is doing two.

[zeeprogrammer]

I must have missed one unless Zee is doing two.

Har har. I suspect more than a few are wondering if I'm even doing one. 
And yes I am.
I think I was number one to start. I expect I'll be number last to finish. 

Good start. Always interesting to see how different people approach the same project.
Even better to have other people show better/correct methods. 

Were the plans posted somewhere on the forum for the monitor engine?
Mike

Yes Mike. The plans can be found in 'Plans and Drawings', OTHER TYPE STEAM ENGINES 10 & 11.
Go for it!

[crueby]

Zee, maybe we should name this one 4.5 then!?!?   

[b.lindsey]

OK, that should do it.

Bill

[sshire]

Zee
My unfair advantage is retirement. Highly recommended.

[crueby]

Zee
My unfair advantage is retirement. Highly recommended.

I second that!!

[Tennessee Whiskey]

With no due disrespect,  you retired a holes can just kiss the side the sun don't reach  . However,  Vern,  great work so fer.  That slitting saw looks like something I would cut BBQ cooking wood with. So, is the 3D printer printing the hull  ?

Cuz

[sshire]

Zee is in charge of the Hull Department.
The engineers at Malco Saw are very helpful. That 5" puppy took the .5" cut in the steel block with not one butt-clenching moment. I never would have done that if they hadn't told me that a full depth cut with a slitting saw was preferred over small bites.