Guys (and gals, too), Since I recently "closed" shop on my part time business, I've been able to start getting caught up on some of the things I got started, but never had the time to finish (one being a 50 cal flintlock-which is nearly finished). Not that I'm necessarily always looking for something to do (the better half offered to provide a list ) but I love the hit n miss engine concept. We have a steam show nearby a couple of times a year and I just love the hit n miss engines and can watch/listen to them for hours. Decided I want to build one (from a kit) by doing all the machining, etc., but I want a small one (about 12" long or so with about 6" or 7" flywheels). I'm not trying to turn this newsgroup into a small engine group, but I was wondering if any of you out there have built the miniature hit n miss engines, or know someone good enough to get some good information concerning what would be a good type. I've kinda got my heart set on the old water cooled type with the tank on top, horizontal piston, etc. I like one called the Associated
but I would like to draw a little from the experience of this group before I dive right in. Thanks. Ken.
There are lots of people out there that sell casting kits. You are a little late. There was a large model show in Detoit last weekend where you could have looked at many models. There is another show in PA in August. A web search will produce lots of hits and you should be able to find some good pictures of various models. There is probably a web site with pictures of last weeks show too. Search for North American Model Engine Association (NAMES)
I heartily endorse the Strictly IC magazines. They're no longer in circulation, but you might be able to get a complete set of issues from the Washburns.
It runs in my mind that I paid about $500 for the complete set. It was a bargain.
You will find one of the most complete listings of model casting sets at this link:
I also recommend Bob Shores' designs. You'll find the link to his site on my model engineering links page:
Just click on "Bob Shores' Small Engines.
If you don't buy one of his designs you can still find a great support group on the FAME site where Bob is the resident guru:
Another person who offers plans is Jerry Howell. I'm not sure if his designs include a hit 'n' miss, or not; but, if you get one of his sets of plans he will be more than willing to offer help and advice.
Be sure to check out Jerry's Model Engineering Tips page.
Thanks for all the tips and links. I'm looking forward to making a nice little hit n miss, but I've got a little bit of research to do first. I don't just want to buy the first casting kit I see, as I realize some will be better (or more complete) than others. I appreciate the info and will keep the group "posted". Ken.
I built the lil' brother hit and miss engine. This is a scaled down version of the associated engine you've been looking at. Castings are provided by Breisch-Peters, the same company that does the associated.
I was very happy with the quality of the lil' brother castings and drawings, so I suspect that the associated would also be good. Also, their prices are good compared to others.
I have built a couple, one was a kit from Paul Breisch, 4" flywheels, .75 bore, runs great, another is a model of a Sears Economy, I think it has a 1.125 bore and 6" wheels. The latter came from Joe Tochtrop, in California. I can get lots more info, just let me know. These are great fun to build and run, take up a lot less room than the real thing. Tom Robeson
Tom, Thanks for the response - I am getting a little more serious about the Associated Hired Man model which is available. I am looking forward (although it may be a while) to giving 'er a spin and getting it running. About time - got a rough guess on how much time to complete one of these (realizing that you guys with experience are able to find "stuff" which is needed, a little easier/quicker than I will be able to do). Ken.
Thanks, Dave, for the info concerning castings and drawings. As I'm just getting into this (not really planning on getting "hooked"), I was wondering if the drawings/prints include info or drawings of the carb, oiler, and other stuff that will be needed to complete these engines - or will I be on my own (with help from the internet). Appreciate the response. Ken.
(Second post - original to Chuck evidently lost in cyberspace) I believe you are incorrect as far as Jay being out of business. I send him an e-mail concerning prices, availability, ship dates, etc., and received an immediate (almost) response as to the questions I asked. Seems like he is still in business and shipping upon receipt of your money. Ken.
The quality of the plans and whats included in the kit varies widely from vendor to vendor. I have seen some kits where the plans consist of several 8x10 pieces of paper. I have seen other plans that are
30 large blue prints and another set that is a thick book (dinky deer)
Some kits are only basis castings and expect you to make lots of parts from bar stock. Other kits include little castings for things like governer weights, springs and even bar stock.
Im my opinion, the absolute best cast iron castings available are from PMD. Bob has several kits from a simple Nova vertical to a multicylinder Fairbanks. The Monitor is a beautiful engine when finished well. I am currently building the Mogul which is a cool sideshaft engine. Redwing makes an excellent kit. The engine looks very nice, runs nice and the kit is an excellent value because it includes all the little things and even springs for the valves. Lot of vendors charge extra for gears, springs, nameplate etc. I have talked to others that have build Galloways and really like them too.
The amount of time to build a kit is very dependent on the builder. For example it took my friend joe about 275 hrs to build his redwing. It took me about a 100 more,but a lot of that was tweeking and changing things to make it run well.
My first project was a PM Research steam engine. That engine took me about 200 hrs to build on a sherline lathe. (its in the sherline brochure if you like to see it) Now I probably could do it in 50.
I suggest you find a kit you like and order the plans. Study the plans and see what you think. All vendors will sell you the plans first. Ordering the plans helps you evaluate your kit vendor and determine if you can handle the project. I have numerous sets of plans where I decided I didn't want to build the kit.
If you are serious about building model engines, go to one of the big model shows. You can look at all the kits and see the engines run. There have been models that I thoung looked great on paper but once I saw it I lost interest. You can also talk to other builders and get their opinion about the quality of the plans and castings.
Another thing to consider. Avoid engines with big bores and little flywheels. They will hit hard and move all over the place. Engines with 6 inch flywheels will run faster than engines with 8 inch flywheels. Most engines with 6 inch flywheels run faster than I like but some can be made to run slow and run well.
Thanks, Chuck, for all the good tips and info. This kind of help is what I needed. I liked the info in your last paragraph... something I hadn't even thought about, but it makes sense about the big bores and small flywheels, but I'm not sure I understand why the 6" flywheels would run faster than 8". I guess if the bore and stroke were identical, this would be true, but aren't the flywheels somehow designed in relationship to the bore/stroke? And isn't it the inertia of the flywheel, quality of the bearings, etc., that determines how often it "hits" therefore the speed? Thanks again. Ken.
Chuckle.... I guess that was a pretty stupid comment that I made - wasn't thinking, but I can see where the situation would arise after completing your first one, a guy just *might* like to try a different model and therefore enters into an "endless loop". Thanks. Ken.
Most important constraint is how much mass is in the flywheel. If you build the a model to scale, the flywheels will have pretty thin rims and not much inertia. I suspect this is related to how some things don't scale down well. (I think inertia is related to the square of the radius??) There are models out there with massive 6 inch flywheels and these will run slow, but I think it takes a pretty competant builder to make a model with light flywheels run slow.
Second item is the cylinder size and compression ratio. A large displacement and high compression ratio will require lots of of energy in the compression stroke so the little flywheels will have to be moving pretty fast. If you want it to run very slow you need a low compression ratio. Some builders claim they go as low as 3:1. This way the flywheel does not need too much speed to compress the air and fuel and the engine doesn't hit so hard that the model jumps and barks.
There should be very little drag/friction in a model and most of it will be from the piston and rings. Ring tension should not be excessive. Piston clearance is important too. One very expericenced builder told me he make a piston out of aluminum 6061 and as it heated it expanded and got tight in the cylinder. A little extra clearance solved that problem.
You need very smooth governer action too. Any binding or friction here will hurt you.
Dependable ignition is imparative. All models use mechanical points. This can be ok, but I have seem models where they try to ground the coil through a rotating bearing which is very unreliable. The absolute best hit and miss ignition system is an electric buzz coil sold by jerry howell. It uses hall affect sensors so there are no contacts to corrode or get dirty so it very dependable. I was the first person to mate this electronic buzz coil with a small model coil and got jerry to start selling the model coils too.
Any way, its a great hobby. Try it you will like it! chuck