Ez Engine Build

[jolijar]

I am taking a basic machining course at my local college and the instructor has been kind enough to let me use the schools tools to work on small projects during open lab time.

I decided to try to build the Ez Engine posted over on the plans forum.

I have all the material required except the 1/4" x 1/16 brass. I need to run off to the local hobby shop to see if they have any in the ks engineering display.

Today I cut out the base and the two square stock parts and faced them to length.

I made the 1.625" long 3/4" square part .0005" too short.
that leaves me with .0525" in between the edge of the block and the edge of the mounting holes. It should be .0575" Can I use this part or do I have to make it over? (its not that big of a deal I have extra material)

the longer 3/4" square part is .0001 oversize. I can live with that.

Both base plates are good.

 

[dparker]

jolijar:
Good for you taking on a small engine to build-----the fun begins.
Don't sweat some of the mounting dimensions (if I'm understanding correctly) just make adjustments for things to fit as they need to on the piston and rod travel. Many models are made that do not exactly follow the plans and will still run very well and nobody will be the wiser (admit nothing and demand proof) if questioned.
Good Luck----don

 

[Twmaster]

"admit nothing and demand proof" <--- Hehe.

Good start Jolijar! Just keep your dimensions in mind where they may be important. You'll be fine. Awaiting further posts on your build.

 

[bearcar1]

Good to see someone else using their time constructively having access to the machines in a shop class environment JJ'. Make the appropriate revisions to the drawings as you go along so that these minor differences do not get overlooked or forgotten about. Of course the goal is to machine pieces as closely to the prescribed dimensions as possible and if one can hit the mark spot on each and every time, then they are a better man than I. Working to .001" to .002-ish" in my mind is considered tolerable. Making corrections to mating pieces is all a part of the game, just continue to strive at hitting the mark as accurately as you can and continue to have fun. Post up some pictures when you can, we would all love to see your progress.

BC1
Jim

 

[jolijar]

Thanks for the votes of confidence. My class is on Tuesday nights so I probably wont have an update till then. I have been thinking about the part that I made undersized and I think that I will be able to use it. On another note I picked up the brass stock for the connecting rods.

I am also taking a welding/brazing class with the same instructor. I would like to build a small boiler for this model after I get it running properly. It doesn't have to be too fancy I just want something to make the engine chug along slowly. The simpler the better though It definitely has to have a safety valve.

Ultimately I am interested in hit & miss engines, model airplane glow engines, and HO scale live steam. But I am taking things one step at a time. More pictures when there is progress.

 

[jolijar]

Update #1
I attempted to build a valve and failed horribly. (lots of chatter and deflection took chunks out of my part)
I was only taking of .010 a pass I might have to take off less next try.

I cut the piston out but it is not at the final length yet its still a bit too long.

I also need to grind flats, & Drill/Tap the holes.

Here is a pic of my piston so far.

 

[black85vette]

When making the valve you can either use a live center to keep it stable or work as close to the chuck as possible moving the work piece out a little at a time to make the next cut. Don't try to extend the valve out far enough to make all the cuts at once. A 1/4" diameter rod is too thin and will flex and chatter if you work too far from the chuck.

 

[jolijar]

Well it only took 3 tries but here it is. Now all I need to do is grind the flat then drill and tap the holes. This valve took about 3 hours and I have spent around 5 hours working on valves total.

Here is a pic with my progress.




What do you guys think?