The Steamboating Forum

My vote is for M6 studs and nuts on Fred's layout above.

Dietrich, you do very nice work Einfach Klasse.

-Ron

fredrosse wrote:Steam engine nuts, I usually get "Heavy Hex Nuts", somewhat more meat in them. USA availability, is there a similar option in Metric?

Not that I know of Fred, but I'll check, I know what my local supplier is likely to say, "Just use a bigger size".

Doubt I'll get much if any done today, too much else going on.

I spoke too soon, I managed to skip a 'task' and sneak out to the w/shop for some pics!
12 M6 in North/South formation shows that the centre four do indeed spanner-foul.
11 M6 in East/West works Ok.
Fred's 14 looks really pretty in M6.

M8 in East/West works but looks a touch 'heavy'

I vote for more and smaller. Looks more like a big engine.

Hmmm! It was nice to dodge the 'domestic overload' and spend all but a whole afternoon on this problem and am rapidly coming to the conclusion that there is no 'right answer'.

After re-learning to use the DRO's P.C.D. function (and getting it wrong a few times, angles in decimals, not degs and minutes!) I tried 8 (14) and it only works (ish) if the two on the join are misplaced to be actually on the join. No biggy you might say, but that leaves the two over the valve port end, VERY close to the edge. 6 (11) works pretty much everywhere in East/West, but as we said, not in North/South. I also tried 7, but that throws up 13??? as a total, and 9 (17) with only one on the join, but that's getting precious close to spanner-foul again on the next four out, but looks nice. I haven't tried that with two (16) on the join yet; that might do the needful, but they would also need the join two misplacing slightly.

Suffice to say I now have one cyl. cover with a myriad of 'magic-marker' dots all round it.

Hi Mike,

If you provide me your bore diameters, bore center to center dimension, number of studs and desired bolt circle, I can do you a CAD drawing with X/Y dimensions. Only takes a minute.

-Ron

Lots of websites with calculators that will just do the math for you.

Great for checking your math...

https://littlemachineshop.com/mobile/bolt_circle.php

-CB

DetroiTug wrote:Hi Mike,

If you provide me your bore diameters, bore center to center dimension, number of studs and desired bolt circle, I can do you a CAD drawing with X/Y dimensions. Only takes a minute.

-Ron

Cheers for that Ron, but I think I have that covered. The ploy was to try and use the tools available. If push REALLY came to shove, I could still resort to the old pencil and paper, how I was taught. Now I do find that quicker than CAD.

Right, first job was to set the block on the miller table, nice and true. I used the finger-clock on the bore edge, checking for the bore centre-line with the 'Y' axis, and at the same time re-proved the bore centres to be exactly 3.3".
Then having eventually re-programmed my head to the P.C.D. function, it has an inexplicable habit of converting some co-ordinates to neg. on entry, in this case the first angle. Most frustrating! I set about plotting all the possible stud number variations talked of above. In the end it boils back down to Fred's 8 (14) being the most suitable, the two on the intersection need moving about 1/16" to find the join and if I move the two at the steam port end a little, they should survive the closeness to the port. That's the only place where 7 (13) with one on the join, would be a mild improvement.
Hole positions on the cover,
and next to the bore.

W/shop time is mighty scares here ATM. Far too much Domesticity going on!

Too late!
The deed is done!

Meanwhile back at the ranch, there's been a delivery.
Not only that but they've been for a spin. Just facing up for now.
The next job is to source some suitable bearings. Talking about sourcing I tried for nuts and studs. Nuts, no problem, I could get the lot (valve covers as well) for just over £6, studs would be almost another £70. I think I might be doing that job I hate. One is bad enough, but thirty odd?


Photos??? I GIVE UP!!!!! The two shown below do NOT show up in 'edit' so are unremoveable.