The Bolton No 5 Vertical Open Column Steam Engine

[MJM460]

Hi Chris, I don’t have the upload button.  Suspect I am not signed in somewhere.  Will lookout my password tomorrow.

Thanks, at least you have confirmed what I am looking for.

MJM460

[Bear]

Congratulations. A real looker and runner. What more could on ask for? 

[Kim]

looks great MJM!  And it runs!  Can't wait to see the video - as soon as the technical difficulties are overcome, that is

Kim

[gary.a.ayres]

Great progress, MJM, and it's looking very nice.

Glad to hear it's a runner... 

Looking forward to seeing the video.

[MJM460]

I think I have it.

Now the trick is, can anyone see it?

<a href="https://www.youtube.com/watch?v=A1A-hB8e1qE" target="_blank">http://www.youtube.com/watch?v=A1A-hB8e1qE</a>


MJM460

[RReid]

Well, I can see it. Looks great, Congratulations!

[MJM460]

Thanks, Ronald,

I will assume that others can also, and add the link back the earlier post for the sake of future readers.

Then I can continue on those finishing jobs.

MJM460

[john mills]

Great to see it running and closer to completed
    John

[MJM460]

Thanks John, glad I was eventually able to get the video to upload. 

It’s always a great day when the new machine first runs.

MJM460

[Kim]

Wow! And she is a runner!   Congratulations MJM!  Glad you were able to get the video uploaded.
Kim

[gary.a.ayres]

Very nice! Running sweetly...

Congratulations!

[MJM460]

Thanks Kim, great when an engine runs straight away.

I am sure the You Tube interface must have changed.  Couldn’t have been my memory! 
I have gone back and added the link where originally intended for future readers.

Hi Gary, thanks for looking in.  It certainly seems very smooth.  My simple attempt at balancing does not seem to have done any harm.  I can relax now while I do the finishing touches.

MJM460

[gary.a.ayres]

I can relax now while I do the finishing touches.

Enjoy!   

[MJM460]

Very slow progress in the last week or so.  I have been thinking about, and making those nuts, plus the studs for the steam chest.

Conscious of the issues Achim had with metric nuts, I had a brief look at what standards I could find.  Google yielded the usual gazzillion hits, which included a bewildering array that were any thing but resembling a standard.  Every reference to ISO seemed to refer in turn to another list of ISO standards without ever specifying any dimensions.  And some, which seemed more promising, started at M5 which did not help much for the M3 and M2.5 nuts I need.

To help make some sense of it all I resorted to my old Drawing Practice Standard which was the text book in student days.  It was based on the imperial measurements we use at the time, but is probably the standard used in all those old drawings we enjoy pouring over, so almost certainly “looks right”.

That standard specified 2D across the points, 7/8D height, and 2/3D for a jam nut or lock nut.  There was also a note that said the nuts were normally drawn at 1D high.

For an M3 nut, this results in 6 mm across the points, or 5.35 mm across the flats, but probably better to aim for using a standard(?) 5.5 mm spanner.  It would be 2.6 high (or 3 mm if 1 D).  The jam nut would be 2 mm high.

For M2.5, the corresponding dimensions are 5 mm across points, 4.46 across flats, 2.2 or 2.5 high with 1,7 mm high jam nuts.  I actually went for a 5 mm spanner which resulted in 5.6 across the points.

The photos show what the proportions look like.

(I tried to put those dimensions into a table.  The formatting icons on the post writing screen, along with all the smiley’s etc, seem to include a table formatting option.  I managed to make a vertical column, but does anyone know how to use these to add additional columns?)

The pictures show the results of my nut and stud making.  The group shot shows three nuts at 1 D high, on the valve rod, piston rod and to lock the crosshead guide rod.  (Perhaps these should have been lock nuts?)

I have assembled one of the columns to the cylinder lower head with a jam nut and a 7/8 D height nut.  The nuts on the remaining columns and the remaining jam nuts are in the foreground.

The studs have been inserted for the photo, with the nuts at 1D high as I felt the extra thread length might be worthwhile.  An extra (unusable stud and a spare nut can also be seen.

I have been looking at the proportions of the nuts for a few days now, and overall, I prefer the 7/8 D high in the M3 size.  However, the slightly higher 1D height of the M2.5 ones also looks ok, though that may be because of the larger dimension across flats.  What do others think?  Or is there a standard somewhere that I should have used?

With the nuts now made, I had to tackle the studs for the steam chest.  Unfortunately, my 5C collet sets do not include a 2.5 mm size.  And I don’t have any 2.5 mm material.  Even the 3 - 2 ER16 would not close in enough to hold 2.5.  So I turned the 2.5 mm studs from 3 mm stock.  The photos show the setup for turning.  Threading the first end was no real issue.  Then parted off.

I tried drilling and tapping a mandrel to hold the threaded end.  I used a lock nut to help with releasing.  Perhaps the brass mandrel was too soft, but for whatever reason, the trial was a failure, I simply could not release the stud from the mandrel without damaging it.  Hence the spare in the first photo.

I then remembered that I have an MT 5 x 3 sleeve so I could hold a second chuck in the head stock.  I have a 16 mm chuck that can close into 1 mm and this enabled the second end to be threaded.  I will buy some 2.5 mm stock when this latest lockdown ends, as 2.5 mm seems a good stud size for these small engines, and using the second drill chuck worked well.  So four 2.5 mm studs duly completed.  I don’t mind cap screws, but studs are better for the steam chest, as they allow the cover to be removed for valve adjustment without the valve chest loosing position.
 
A few more finishing touches off the list before reassembly.

Thanks for looking in,

MJM460

[gary.a.ayres]

These will make the engine look really handsome when it is done!