"Catherine", a USA "Sweet Pea" engine build

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Benjamin Maggi
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Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

Thanks!
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
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Benjamin Maggi
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Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

Wow, it has been almost ten months since I posted anything new on this thread about my engine, and at times it seemed like nothing new was accomplished. Right after my last posting on May 28 (my birthday!), we were in the process of setting up the pistons and getting them properly spaced on the piston rods. After some discussions on this, we both came to the realization that it didn’t make sense to get the engine chassis assembled and timed properly if I was going to have to then strip it all down to paint it black. Better to do that first, and then finish assembling and timing it. Sure, others have done it the reverse way but this seemed more logical. If I scratched it up during assembly, hitting it again with black spray paint to cover the marks wouldn’t be very difficult.

So, I loaded up the parts into my tiny Toyota and drove it to my place. It was really starting to add up weight wise! Because of the covid, I was at home a lot more and during the summer I had plenty of time to break everything down, clean it with lacquer thinner, prime it with Krylon primer, and then paint it with Krylon satin black. No matter how hard I tried to clean and prime everything though, the black paint sure seems to want to chip off the edges and corners if you look at it wrong. Oh well, I can touch it up later and real engines don’t stay in perfect condition for long.

After it was all painted, a process I dragged out for several months of on-again, off-again work, I brought it back to my friend’s house and we started to assemble it again. However, each week seemed to introduce a new problem. We started by assembling the chassis loosely and noticed that even with just the side rods on it didn’t turn over smoothly. After much fretting and measurements we noticed the coupling rods were not the same length! During construction months ago we had noticed that everything wasn’t lining up properly and determined that the connecting rods, though built to the plans, were an inch too long. https://modeleng.proboards.com/thread/1 ... oblem-helpWhere the discrepancy came in I don’t know, as I assume others have built the engine to the plans (though the Sweet William 7.25” gauge design is much less popular than the Sweet Pea 5” gauge design) but we had to shorten the rods. In the process, we made them different lengths. Last spring I was in the throes of terrible medical issues and the error was likely caused by that. We just weren’t noticing it until now. So, we had to correct one of the rods by shortening it even more.
Rods are different lengths.JPG
Then, we noticed that the cylinder covers had too much of a boss on the back that fit into the cylinder, and the piston was hitting it. It was an easy fix, but took time. Next the crosshead slide bar on one side was just slightly out of parallel with the frame and the bracket that held it had to be remachined. The coupling and connecting rod brasses needed fiddling and scraping until they turned smoothly on the crankpins. The hardware holding the rods together, originally threaded rods with nuts on each end, were replaced with stronger socket head cap screws and only one nut to reduce the amount of play. And like that, last fall and winter slipped by as each week we would discover something new that had to be adjusted.

It was frustrating. I am sure anyone who has built or owned a steam engine is familiar with the testing process, but it was new to me. The Sweet Pea book by Jack Buckler doesn’t talk about the pain of doing it. He just makes it sound like everything will fall together without problem. That isn't reality, though. After each piece of the value gear is added it might need adjustment to take out the slack, or else by the end it will be a mess of mis-fitting parts due to an accumulation of errors and sloppiness. That takes time, and many nights I wanted to throw in the towel.
Adding valve gear piece by piece.JPG


My shop mentor and friend, thankfully, knew how to correct the issues. This engine might be mine, but his blood and sweat are in it too. He did, on more than one occasion, point out that I could have built a popular engine like an Allen mogul which had all of its issues vetted. That was true, and I sometimes wonder if I should have taken that route. Still, some projects were enjoyable, like making the paper gaskets based on advice I got here on Chaski http://www.chaski.org/homemachinist/vie ... p?t=109898 It was the perfect project to work on during a rainy day.
Paper cylinder gaskets.JPG
Finally, we were able to test it by putting a belt around the wheel and hooking it up to the end of a motor. Actually, several motors, as we caused the first one to smoke and burn! But, right now I am pretty happy with where the chassis is. The picture below doesn't show all the parts on it, but I don't always remember to bring my camera.
Motor and belt driving wheels..jpg
The only major work to be done is fabricate the rod that connected the top of the vibrating lever to the slide blocks on the top of the cylinders. That will come as we work on the final timing. I have said “we only need to time the chassis and it will be done” for several years but I now actually believe that it may occur in 2021.
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
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Adirondack
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Re: "Catherine", a USA "Sweet Pea" engine build

Post by Adirondack »

Hi Ben. Any updates?

Thanks

Chris
Adirondack Car & Foundry
Check out our projects: https://www.facebook.com/ADKrail/
Visit our ALL-NEW online store: https://adirondackcarfoundry.square.site/

A little locomotive with 4 wheels on the track is a lot more fun
than a 1/2 finished one with 16 wheels on the bench!
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Benjamin Maggi
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Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

No, but part of that is because I was hoping someone with experience timing the engine could come over and help me through it. We would start and run into a snag, and then I would need to ask for help and wait for an answer, then try and time it again. Over and over. People were friendly and sent me resources (articles, valve gear software program, etc.) which is all nice but what I really need is someone who knows how to time Hackworth engines to help us out. It is quite time consuming and we lose our entire night's work session if we run into a question, or a fit interference, anything actually... and need to stop and research it.

Sadly, no one at our club has an engine with Hackworth. One guy was really helpful and walked us through about 1/2 of it, but he hasn't been able to come back so we are just in a holding pattern for now.

Oh, that and my newborn son...
Last edited by Benjamin Maggi on Thu Jun 09, 2022 6:33 am, edited 1 time in total.
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
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Harold_V
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Re: "Catherine", a USA "Sweet Pea" engine build

Post by Harold_V »

Benjamin Maggi wrote: Wed Jun 08, 2022 7:57 pm and my newborn son...
Congratulations! May he have a long, healthy and productive life.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
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Benjamin Maggi
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Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

Thanks!
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
User avatar
Benjamin Maggi
Posts: 1409
Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

After 16 months of ignoring it, I decided to start working on the engine again. We had hit several roadblocks last time we tried timing it, and now we had to correct them. First off, the chassis needed weight on it to simulate how the suspension would settle once the actual boiler was in place. I asked on the Sweet Pea Facebook group and was told a Sweet William boiler was about 140 pounds (empty). So, I purchased 120 pounds of tube sand and hauled it over to my friend's workshop. We set it up in a bucket and set it on the chassis and the axle box springs compressed a bit.
IMG_4504.JPG

We then realized we needed more weight, so we started adding surplus metal vices that were laying about the basement.
IMG_4508.JPG

Then, we took some set screws and drove them through pre-drilled and tapped holes in the axle box steel retainer bars (this design feature was part of the original plans) so that once the extra weight was removed, the axle boxes wouldn't spring back down. In the picture below, you can see them sticking down about a 1/2". I may go back and replace them with proper, shorter bolts at some time, but for now they are fine. Naturally, once the engine is finished they will be removed and the chassis will again be re-balanced for weight.
IMG_4507.JPG

At the recommendation of another friend, we then lowered the chassis onto the floor of the shop which was covered with rubber anti-slip tiles and pushed it around. Whereas before we had either set the chassis on a rolling road or propped it up on blocks and tried to rotate it by hand while grabbing the rims of the wheels, now we could easily push it along on the rubber floor. Or at least it should have been easy... we hit a couple of snags. Though the motion brackets which held on the ends of the slide bars were laser cut to plans, the coupling rods (connecting the drive axle to the cylinder) were hitting portions of the brackets at their upper-most revolutions. So, we removed each one in turn and machined more metal away and then carefully reinstalled it so as not to dislodge anything else.
IMG_4505.JPG

The weighshaft bracket, which held a valve gear slideblock on each end, was also sliding back and forth between the brackets which extended up from the frame. The plans were somewhat vague on solutions for this, but I purchased some collar clamps and installed them (one per side) on the weighshaft just outside of the frame brackets. They don't look great but they should work well, and perhaps someday I will replace them with a more elegant solution.
IMG_4506.JPG

Finally, the chassis rolled freely back and forth along the rubber floor. It is still stiff, suggesting that it might need to be broken in by towing it along at the club, but at least the problems we experienced before (valve gear binding or hitting other parts, pistons hitting cylinder covers, valve gear sliding around, etc.) are gone. Hopefully.


Another friend had helped us immensely with the timing of the chassis, and we nearly got one-half done when the problems described above forced us to stop and take corrective action. Hopefully, I can get the other half timed.
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IMG_4509.JPG
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
User avatar
Benjamin Maggi
Posts: 1409
Joined: Wed Apr 25, 2007 10:38 pm
Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

After 11 years of work, my Sweet William (a 7.25" gauge upscaled version of the 5" gauge "Sweet Pea engine) chassis finally ran on air! A lot of thanks go to my friends Warren and Mark, who had the steam locomotive and machining experience to help me get this far with timing the engine. We discovered that the original return crank design isn't optimal and one of them kept rotating on the end of the crank pin no matter how much we tightened it, and every time it did that the valve gear would jam. But, I can remake those parts.


It turns over by hand but not easily (though without binding), and running it on air to work it in might be possible but it will take an awful long time. So, I might need to take it up to the live steam club and pull it around for a bit to help it slowly break in.

There are some loose bolts to tighten up, some cylinder gaskets that I might want to remake, and we realized that I hadn't installed the piston rings yet (they were sitting in my parts box, safe from damage). I didn't know you needed them installed to run the chassis on air (oops!). Thankfully, we can install them without undoing all of the timing work that went into the engine.

But, it is nice to finally get it to this point! A big thanks to my friends Warren and Mark for helping me time the engine.
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
Mike Walsh
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Joined: Sun May 06, 2007 10:14 pm
Location: St. Louis, MO

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Mike Walsh »

Congratulations!! Glad to hear it. When do you plan to head to the track? I'm headed to FLLS in May for a Roc visit. Need me a garbage plate!
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Builder01
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Re: "Catherine", a USA "Sweet Pea" engine build

Post by Builder01 »

The May "Run and Rides Day" is May 20th. Maybe we'll see Ben or Mike there?? Bring your Sweet Pea, Ben. Is it 7-1/4" gauge? I'll be running steam on the 4-3/4" track giving rides from 1 to 4. Lots of time to visit afterwards. Mike, bring whatever you can. David.
jcbrock
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Re: "Catherine", a USA "Sweet Pea" engine build

Post by jcbrock »

Congratulations Ben, it has to feel like a major step. I'm close on my loco (I have my rings installed!) but am doing some painting. I found I needed to have the reverser etc in place to hold the link blocks before setting the valves. It's always something, but eventually you get there if you keep at it. Looking forward to your first run on steam!
John Brock
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Benjamin Maggi
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Location: Albany, NY

Re: "Catherine", a USA "Sweet Pea" engine build

Post by Benjamin Maggi »

ME TOO! :)
"One cannot learn to swim without getting his feet wet." - Benjamin Maggi
- Building: 7.25" gauge "Sweet Pea" named "Catherine"
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