Stew's Simple Mill Engine

[divided he ad]

Good Start Nick 


We're all watching now so expect plenty of  if you slow down.....

Need plenty of  and some of  myself.....  still haven't finished my rocking engine from 2 years ago! 




Still, will be good to see your progress.   

 



Ralph.

[NickG]

Thanks Ralph - yep, I'll need plenty of those.

Seriously, 2 years for a rocking engine? You need more than a   

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Seriously, 2 years for a rocking engine? You need more than a   

 

Yeah, I know... Time passes so very quickly!


One day 







Ralph.

[Tennessee Whiskey]

It does fly by, but look at the beautiful glow you've shed on the world with your torches. It's all relevant.

Yalls Redneck,
Eric

[NickG]

Quick update - I've been slowly continuing work on the main bearings and have finished them bar the top coats of paint. The dimensions did not
come out as perfect as I would have liked ( dials on the mill aren't great even when used in metric it seems!) The main holes are also slightly off centre, however the main thing is that the holes are in the same position relative to the bolt down holes! The crank will line up ok. Deviated slightly from the drawing, the base of the bearings are 36mm wide rather than 38 ( I didn't fly cut enough down to thickness!) and the bushes are 13 mm OD rather than 14 as didn't have a 14mm drill and don't have a boring head yet. Used an 8mm end mill to finish the bores as don't have an 8mm reamer. Finish is good but prob slightly oversize. This does not matter as I will be turning the crank due to lack of 8mm bar! Still making things difficult for myself - should have just gone and bought the metal!

Another pic attached with first coat of grey primer - for me things always look decent in undercoat but rubbish when finished!

[swilliams]

Looking good Nick.

Steve

[vcutajar]

Missed this build thread but now up-to-date.  Good progress there Nick. You are just like me.  My builds are very slow also.  But then again we do not have a deadline.

Vince

[Don1966]

Hi Nick, just catching up on your latest and she's looking good. Any progress is better then no progress and we are not in a hurry here are we?

don

[NickG]

Thanks guys, am just about to go out and do a little more. You're right, no time limit but I just get frustrated and want everything done yesterday for some reason!

[NickG]

Painted the bearings the other day and they turned out reasonably well,nothing fancy just kept everything square as hate filing radii etc. Never been properly taught how to use a file so have never been any good at it.

Got a bit more done tonight, just the slide bars. I didn't have enough 1/4" square section steel but did brass. Nothing major here just mill them to length then drill holes in same place on each bar - the only critical thing being that in their pairs, the holes need to line up. Annoyingly, I am yet to find the centre of something accurately on this project, they are the same though which matters more!

Will Probably do the supports and spacers for the slide bars next.

[arnoldb]

Good going Nick 

You're right, no time limit but I just get frustrated and want everything done yesterday for some reason!

Bah - we all want that    The journey is a lot more fun - usually in retrospect though

Filing....  Most likely you'll end up loving to hate it, or hating to love it...  The hating to love it bit seems strange, but there's something about wielding a corrugated bit of steel and rubbing it against other "stuff" to make bits come off that can be immensely satisfying 

 , Arnold

[Jo]

I find filing very easy and satisfying but having spent 6 months of my apprenticeship being taught to file might help 

Filing radi is easy with a button. Then there is that old trick of using a marker pen to identify the high points that need filing and making sure you centralise your filing on the mark.

Jo

[NickG]

Probably something I should practise, fine with filing buttons and I can see less chance of messing up than trying milling with rotary table.

[NickG]

Done a bit more - not a lot but never mind! I turned the supports for slide bars, little different to Stew's design because I had some 10mm 303 stainless to do them out of and thought it would be less metal to take off! I've also used 3mm threads in both ends.

The stainless is funny stuff, can achieve a really good finish but strangely it seems to like a fast feed, same seemed true when drilling it. It gets quite hot when turning it too. The only thing it didn't like was being parted off so I stopped promptly, sawed and faced instead - this meant a bit of faffing around measuring to get them all the right length. Chuck backstop would have been ideal!

I then realised I didn't have any 3mm screws long enough so had to make some studs! What a pita lol! I had some 1/8" stainless which meant even more of a pain having to turn them down in the collet chuck from the milling machine a little on each end first. Listen to me complaining - there were only 4 of them lol! Luckily 1/8" passed through the clearance holes I'd drilled.

Next was just some spacers - for this I decided it would be easier just to do from some round - drill a deep hole and part the 3 bits off to desired thickness to give a little clearance for the cross head material (1/4" sq steel). This time I used some 7mm mild steel hex - don't know where it came from but it cuts really nicely and parts off easily. You'll notice in the pic that the back left spacer is missing- this one will be done from square as it has a hole in it which acts as a valve rod guide.

A bit early for an assembly I know but had to do it to keep myself motivated!! I was quite impressed with the way the slide bars and supports went together everything seems nice and square. Just got to do the rest of the engine the same and it might be ok!

[Don1966]

Pretty good progress from what I see Nick. She's shaping up nicely.

Don