Micro hosc build

[Mitchg07261995]

Hi all, I started making the micro hosc engine in my class during free time, like during our 15 minute break that we get one time per day. I am building this and a stirling engine at the same time so i am just working on the hosc when i find a spare few minutes. Im thinking of going in on tuesdays and staying from 7:30 am-3:45 when i normally get out of class to get alot more done on the two engines. I ordered some of the really tiny drills that I need for this engine today from tool king.
any way here is what i have this far.
flywheel, .250'' diameter with a whole in the center from a #60 drill

with air fitting for the engine, i just need a .020'' drill which should be here with in the next 2 weeks

and just to show how tiny these parts are, here is the cylinder back plate to my stirling engine that i am building, the graph paper that it is sitting on has 4 squares to the inch...

mitch
P.S thanks for the plans Steve!

 

[stevehuckss396]

Nice start

 

[Mitchg07261995]

Thanks Steve I hope to start the shaft on monday

 

[Mitchg07261995]

im thinking that i dont have amount of skill needed to make the base for this engine as shown on the plans, so i am thinking of sourcing someone that would be able to do it. I can supply material, and pay for the part. I am thinking of trying these people out
http://www.emachineshop.com/
hey Steve, what did you make your crankshaft out of? im thinking of making it out of drill rod

 

[Tin Falcon]

the main point of building these engines is to build the skills. sometimes you need to make a practice part or 5.
if you want a steam engine buy a kit there are several for under $150 pre machined just assemble.
look at the bottom of my getting started in model engineering thread.
Tin

 

[Rivergypsy]

You'll be fine, Mitch. Just take it one step at a time. If you have a think through the different operations, and write them down, each time thinking how you'll hold it for the next op. Personally I'd block it up into a rectangle of .375x.406 but deeper than the finished part, so you have something to hold on to. Then hold on to the base of that, and nip around the uprights (very, very gently) before putting the .025 holes in. Then work from each side and get the side holes in, before slicing it off of the bar with a slitting saw.

Easier said then done, but just break it down into stages, and be very gentle with it

 

[Mitchg07261995]

ok, I see your points. I do need to work on my skill, ill take this part slowly and think out every step before I do that step of the part. I see what you mean of leaving the part on a oversize of stock,because yesterday when I tried to make the base I got it roughed out. I had the correct thickness, width and length but accidently tightened the vice to much and crushed the part
Ill go look at the drawings study them, then write down on post it notes of the operations that I will have todo. I cant wait to see the #80 drill that i ordered along with a #67, #71, #75, #76

 

[Rivergypsy]

With those drills, high spindle speed, tiny pecks & a good quality coolant/cutting oil - you've got small toys there

 

[stevehuckss396]

I think i made the disk from brass and pressed spring wire rods into the disk.

 

[Mitchg07261995]

is the one in your pic that is not completed, the same one i am building or is it the one above it?
i like your idea Steve for the crankshaft, i think that is what i will do

 

[stevehuckss396]

The two outside engines are full size. The top center is half size. The bottom center is 1/4 size. You are building the bottom center, quarter size engine.

The one on the dime.

I have also built a double size single cylinder and double size with double cylinder.

 

[Tin Falcon]

Mitch IMHO set the tiny one aside build the full size version then go back to the tiny one later. tiny engines require greater precision and better fir and finish.
Tin

 

[Mitchg07261995]

Wow Steve that really is tiny! I cant wait to have this engine completed

 

[Mitchg07261995]

Steve, have you got any tips for drilling these tiny holes in the base and various other parts?

 

[stevehuckss396]

Steve, have you got any tips for drilling these tiny holes in the base and various other parts?

The obvious ones are to drill with light pressure. It takes forever to drill tiny holes. Lube like crazy. Buy top quality bits. Spin the drill as fast as you possibly can.

 

[Mitchg07261995]

The obvious ones are to drill with light pressure. It takes forever to drill tiny holes. Lube like crazy. Buy top quality bits. Spin the drill as fast as you possibly can.

thanks a bunch steve! I will keep that in mind when i get my bits

 

[Mitchg07261995]

I ordered a .032 endmill from ebay and sent a seller a message to see if he would combine shipping on a 0-80 tap, micro boring bar with a minimum bore of .032 and a 1/8 carbide endmill

 

[Mitchg07261995]

i dont think ill do any more work on this engine till my drill bits, endmills, and boring bar comes in the mail. Here look how tiny this baby is!
http://www.ebay.com/itm/321098028043?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
for now i am going to focus on my stirling engine

 

[Mitchg07261995]

well most of my tool's arrived today, Im just waiting on a few drill bits
heres what I got
micro boring bar with a minimum size whole of .032

#80 drills, one is bent

1/8'' carbide 2 flute end mill and 0-80 tap

0-80 screws with fillister heads

Boring bar with .032 solid carbide 2 flute endmill

Parts that are done, and almost complete

 

[Mitchg07261995]

hey steve, do you have a spare 000-120 screw? I am having trouble finding just one and dont want to buy in large quantaties. Also where did you find your 000-120 tap? for the cylinder? Do you think it would be possible to just enlarge the 000-120 whole a few thou to accept a 00-90 screw which my local hobby store carries along with 00-90 taps. Thanks Mitch