Economy advice

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CMS

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Starting work on an Economy casting kit and was fishing for any tips, helpful hints, do's or don'ts, etc. that those of you may be willing to share. I've been working on the crankshaft, and so far so good. All that should be left to do on it is cutting the keyways. Next I thought I'd work on the base and water hopper/cylinder, so any advice on this subject, fire away.
 
Thanks for the link SD, some very good ideas from a few good pictures. And the kit I'm working on is Joe's version.
 
CMS, it has been quite awhile since I built the Economy. It was my first I.C. hit & miss engine, so I have special attachment to it.

If there is anything I can help you with, please ask and I'll do what I can.

This is a video of the Economy.

 
Thanks for the note of encouragement PPM, as this will be my second gas engine, but my first from castings.
 
CMS, one of the negatives with working with castings is if you screw one up, it is hard to recover. It may cost you another casting.

The first thing I would recommend for you, especially on the main casting, is to do a layout of all the details (holes & bosses, etc.) on the casting. As I recall, some of the locations of the bosses are not quit on print location. If you do a layout it will allow you to move the entire pattern to more effectively fit the casting.

Another hint I have used on all of my cast engines is this. Once I have established a decent layout the first thing I machine is a flat bottom on the casting. This can require a somewhat difficult setup. Once it is setup and the surface has been flattened, I drill and ream a 1/8 shallow dowel hole on each of two sides of the casting. It can be either side to side or front to back of the base. Then I drill the 4 corner mounting holes on location.

Next I take a 1/2 or 3/4 thick piece of steel or aluminum that is a little larger than the base of the casting, square it up nicely, I drill and ream the two dowel holes and drill and tap the 4 corner holes on the same location as the casting.

From this point on, you can fasten the casting to the plate and do all your maching setups with ease. Once you have a difficult setup, you can remove the casting from the plate and replace it on location without disturbing the setup. I think you will find this very helpful and will be surprised how many times you have to repeat setups.

Looking forward to following this build.
 
Thanks again, and I'll try to post updates on my progress. But this time year progress might be a little slow. I do have a question for you, what did you use for the main bearings? In following a crazy ol' farts advice :p my mentor has advised to stay away from the needle bearing and use a bushing.

DSCF2739.jpg
 
CMS, I used needle bearings on my Economy because that is what they called for. I have built many engines since and have used oil lite bushings on all of them. I don't know why your mentor said to stay away from needle bearings, but I can tell you they are not necessary.

This is the tooling plate I started out with. Since I have built 2 Atkinsons, 2 Red Wings, One I designed & built on my own, & have 2 Associates that I will be starting before long. As you can see by the number of holes, the plate has been used extensively.
SetupFixture.jpg


These are some of the setups I have used the plate for. The photos are of the Red Wing engine.

Locating the cylinder bore.
Locatebore001.jpg


Machining & tapping the crankshaft journals.
Machiningframe004.jpg


Boring the crankshaft journals.
BoringCrankHousing004.jpg


Line boring the cylinder on the lathe.
Boringcylinder002.jpg


The time you put into the setup plate will not be wasted.


 
Sorry there's not much to report and for now nothing to warrent posting pictures, but I have be able to get the sleeve bored and the piston is done. And per the prints, the bore is 1.125" and the piston is 1.123", SMOOTH!!! But with the rings installed on the piston, MAN, that dude is tight!!! And .002" end gap for the answer to that question. But are the rings suppose to be tight-tight??? On my other engine I used O-rings and things weren't quite so tight.
Anyway, hope to have the sleeve in the block and the block mounted to the base soon and then I'll try to post some pictures,
 
Run it in for an hour or so and the rings will bed in and become smoother, compression should also get better. You want a couple of thou clearance so the alloy piston can expand when it gets hot which it will do faster than the iron

Jason
 
CMS said:
But are the rings suppose to be tight-tight???

Are you sure you have the correct depth and axial clearance for the ring grooves in the piston. ???

Ask me how I know. :-[

Best Regards
Bob
 
Thanks for the advice guys. I'll keep the break-in in mind, but it's going to be a while before it gets to that stage in the build. As far as the ring groves, I was thinking that if .002" of piston to sleeve clearance was good enough, ( per the plans ), then that should be good enough for the rings for both depth and width. Now for those of you that have way more experience than I at this game, is that allowing enough clearance? Any thoughts on staying with the aluminum or should I make one from cast iron?

 
Starting to look like an engine now. It's taken me a blasted year just to get this far, hope that I'll have it done inside the next 3 years.

DSCF4199.jpg


DSCF4200.jpg


DSCF4201.jpg
 
Thanks, I've been knocking away at it, little by little. I have moved my updates down to the "Work In Progress" area, so you may see my blunders there.
 

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