Little Engines Crab - Son's first locomotive

[Jacob's dad]

My family has been involved with some form of steam engines since 1962. When I was a boy I was fascinated with the live steam hobby so as I got older my father and I started building Clishays. We never finished them because other things got in the way but we did have all of the boiler materials besides most of the materials to build the engines. Fast forward ahead until about three years ago when my youngest son, who is a steam fanatic also, decided he wanted his own 7-1/2" gauge locomotive. When he found one for sale he came to my wife and I and asked for the $,$$$.$$ and when he told me the price I told him he was on his own and would have to save his own money for it. He started selling lemonade, and then moved to plants from his grandfather's nursery, and then to bird houses because they were something we could make together and we could store them easily when he wasn't trying to sell them. He set up a stand at the end of the driveway, and went to a model train show and even sells his items at the live steam meets. He sells everything from bags of wood chips that he calls "steam engine starter fuel" to his bird houses that he would place on his flat car behind his speeder.

When a Little Engine's Crab came up for sale on Discover Live Steam, I emailed the gentleman and then called him and we spoke for quite some time. I explained that my son was trying to buy his own engine and I asked him if I could talk to my son about this engine and then get back with him the next day and he said that was fine. I sat down that night with my son and explained to him how long he has been saving and how much he has saved, and that he should consider the Crab on DLS because I just happen to have all of the boiler materials for a boiler that should work on this engine and that he should sleep on it and let me know the next day, so he did and the next day he said he would like to buy the engine because he thought he could be under steam faster. I called the gentleman back and told him we would take the engine and then we kept in touch for a time period until we would both be near each other so we could pick it up. We went to a meet in GA, and we made arrangements to meet on our way back so we met at his family's place and we looked the engine over and my son purchased it. On the way back we just had to stop by two of our friends and show it to them and they were very excited for him.

We didn't get any drawings with it, and it wasn't a casting kit so all we have is the chassis and it runs on air. That brings us to where we have a few questions for this project and I have listed them below.

1. What was the original boiler design for this engine? The boiler material we have is 8" pipe x 14" and will have a 6" x 6" firebox with (36) 1/2" copper flues.
2. What was the original water pump design like? I have been informed by a fellow Crab owner that this is not of the original design. I am just curious what it was like.
3. What was the design for the top of the frame rails/floor of this engine?
4. Did the plans call for oil or grease on the crank pins. The rods still need to be drilled and have the oilers/grease fittings added.
5. How are the gears lubricated? Do they have an oil bath?

We plan to kit-bash this engine into a narrow gauge logging style locomotive and my son can pull a few empty log cars since we understand that they are modest pulling engines. I am familiar with one Crab that a friend of mine built and it would pull two adults on a track that had about a 2-3% (?) grades and it was impressive for the size. We came up with a couple of sketches while on our way back from GA and they are below. If we had two of these we would build something similar to the Davenport Duplex Locomotive as shown at this link: http://gearedsteam.com/davenport/duplex/duplex.htm

I am sure we will have many questions to follow, but we would like to hear from other crab owners and items they have had to work around or modify on their engines.

Thank you in advance,

Jeff Smith

[NP317]

Jeff:
Contact Little Engines about getting a set of plans for the Crab design.
That might answer many of your questions.
And Congrats to your son for sticking to his plans and making them happen!
~RN

[Jacob's dad]

Thank you RN. I have emailed Mike and will wait for his response. I understand that many of the vendors have to work and it may take a few days. If you need a caboose bird house let my son know because my wife would love to have them out from under the island in the kitchen....lol.

[Ray Cadd]

What a great story...that's sort of the way I acquired my first locomotive. I don't think you'll be disappointed with the Crab. It's a lot of fun, and very easy to handle. I 'narrow gauged' mine too- I'll try to post pics here, or you can go either to my FB page or Mike Massee's (Captain Harlock' to chaski readers) web page...google Mike Massee Photography.

[Jacob's dad]

We nearly have the boiler ready to weld and I want to drill and tap all of the holes in the outer shell before we go any farther. The old Modeltec issues show the boiler fittings as brass compression fittings with 1/8" pipe threads and 1/4" compression fittings. After doing some research on those types of fittings, a lot of them are not steam rated and some of them were as low as 30psi for the maximum pressure. I did find many that were 150 psi rated, but were not steam rated. Many of them had a maximum temperature rating of 250 degrees, and steam at 100 psi is 337.888 degrees F. Where I am going with this is that my son has done a great job of funding this project himself and it has really helped to build his confidence in the shop and the hobby, and are there any fittings out there besides scale model fittings that meet the requirements for steam ratings but don't cost an arm and a leg? We hope to have the boiler finished by the end of the next month and it will be another learning experience for him if he has to place his project on hold and hit the streets selling his bird houses to pay for scale model fittings. I am teaching him how to do an excel spreadsheet with all of the boiler fittings and jewelry so that he can see what it costs to build this project, and it is not completed yet, but I bet when it is finished it will be more than the price of the engine and the boiler thus far. I have spent last evening and this evening on various websites from AME to PM Research to McMaster and Grainger and there doesn't seem to be any alternatives out there for the world of fittings. Another big ticket item is going to be the lubricator at nearly $300.00, and that is a big deal for a 12 year old. I am considering a displacement lubricator, but as small as they are I think he would be filling that up every 5 mins. What are some options for the lubricator? I know at the club track some of the people have something that they crank every few minutes and I can look at those the next trip as an option, but I like the idea of the AME dual feed lubricator. Any ideas or suggestions would be greatly appreciated so that we can keep moving forward on this project.

This has been a great experience for him because he is now learning how to operate the lathe and he drilled nearly all of the tube sheet holes once I showed him how to do the first few. For me though, there are no breaks now, as soon as I get home from work there is no rest and he is busting my chops to get out to the garage to get to work and he will stay in there as long as mom will let him until it is time to get ready for bed. He even has all of his school work completed and is ready to go when I get there, but I don't even get to sit down. lol

Thank you in advance for any assistance or suggestions on the fittings and lubricator options.

[Fred_V]

I don't think there is any problem with using stock fittings. Just don't use any that have a plastic sleeve in them. Ones with a brass ferrell work fine as well as the flare fittings.

For a lubricator some of the guys at Ridge club had made a manual lubricator. It was a little spring loaded device with an oil reservoir on top. You pulled back the spring loaded plunger and the rest was automatic. They would pull on it a couple of times per lap around the track.

[Mike Walsh]

I think it would be helpful to post a sketch of the boiler and show the lines that you will have plumbed on the locomotive. This doesn't have to be limited to the boiler fittings, but could include water line fittings, etc.

Being that it's his first engine, it might be helpful to consider compression/flare fittings from McMaster Carr. I am fond of flare fittings as they provide a better seal. I've often found compression fittings to be loose even after tightening them. Then they break.

Flare fittings cost a little money, but are usually easy to work on. Don't be hesitant to use steam rated fittings from McMaster Carr either.

It really depends on if you guys want to go for the scale look or if you just want to get it running. For our senior project in college, we used standard off the wall fittings from Home Depot, ensuring that they were of appropriate ratings. It got us running on a minimal budget. You're looking at $15.00 for a home depot fitting vs $35+ for a scale fitting.

Check out page 450 on the McMaster Catalog. An example model number would be 47865K41 .

Just throwing that out there. Have fun!

[neanderman]

What a great story. When I was about his age, my parents told me the same thing when I wanted: a new baseball glove; a new bicycle and a 35mm SLR (in that order, over about 6 years.) It instilled in me a real understanding of the value of a dollar, of the benefits of saving and how much more something means to you when you've spent your hard earned money on it. Kudos to you and your wife for instilling these life lessons.

Please keep us informed of your son's progress!

[Jacob's dad]

We were at the December meet at our club and a friend asked us for an update on my son's engine so here are some progress photos. He has sold the dickens out of his birdhouses and firewood to keep his project going so we are proud of him learning to work for something he would like to have. A great friend in the hobby has been helping him along with his project in his shop and he showed him how to set the boiler up in the mill so all of the holes he would drill would be in line and on the outside of the radius of the boiler shell. He drilled all of the holes and was able to tap the smaller holes, but I had to help him with the tap on the 1/2" and 3/4" washout holes. He drilled all of the holes and then we cleaned out the boiler and now we just have to put the top tube sheet in so we will be heading back to our friend that does the pressure vessel welding and he will put that in for my son. He did all of the other welding on the boiler for him and he even has a few large antique steam engines like a steam sawmill that we help him with sometimes so he was kind enough to weld this up for him because of my son's love of steam. After that, it will be a lesson in cutting the tubes to the proper length and all that is involved with installing them. He said he is looking forward to learning how to use the tube roller so that should be fun for him. He is really looking forward to the day that we do the hydro and then taking the boiler over to the club for their inspection. We have taken it over as we progressed and have received a lot of positive results thus far, so that has been very encouraging for him. After that, we will mount it on the frame and get it piped and then take it for another inspection and if he is granted a boiler certificate we will take it for a test run and that will probably be the highlight of the project for him, because I know it will be for my wife and I. He has learned a lot during this process and he is already talking about the next engine he would like to build and he talks with the owner of those casting sets every meet that he seems him and also goes for a ride with him until he loads up and heads home. He is making some new items now that he will be bringing to the FLS winter meets to try and fund that casting set so that should be a fun project once this one is completed.

[Jacob's dad]

I don't know why it rotated the last three photos. Sorry about that folks.

[LVRR2095]

As far as a lubricator is concerned.....I wouldn't worry about one very much. You will be running saturated steam and the cylinders will be plenty wet. All you need to do is to make sure you get oil into the cylinders after each run....so they don't rust. A simple plug in the steam chest cover that can be removed after each run will suffice. Squirt in some oil and move the locomotive back and forth until you see oil coming out of the drain cocks and you're good. You can always add a lubricator later. Another inexpensive way to go are simple displacement lubricators with a valve to control the feed screwed into the steam chests. You can choke down the feed to practically zero as a again....you are dealing with wet steam. Even with simple displacement lubricators....I would still manually add oil to the cylinders after each run.
Keith

[Soot n' Cinders]

I would absolutely put a lubricator of some kind on there, water is not a lubricant and it will probably squeak and will wear out faster. A simple displacement lubricator from American Model Engineering would do, as would a mechanical lubricator.
I do agree about adding extra oil at the end of each run if it's iron cylinders.