Author Topic: Potty Lads and Dads Mill Engine  (Read 32540 times)

Offline sbwhart

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Potty Lads and Dads Mill Engine
« on: April 15, 2013, 02:13:27 PM »
I have an old works friend who's just getting started in Model Engineering along with his 11 year old son who's his showing a great interest in engines with a developing tallent for 3D CAD. Chatting to them got me thinking about an engine that could be built in a relative short time with limited equipment and I came up with the simple mill engine design that I showed the drawings her http://madmodder.net/index.php/topic,8128.0.html (be warned it has mistakes) that a Dad or Grandad could make together

Hence Lads and Dads.

The design is based on this engine that I saw at the Northern Mill Engine Association at Bolton at their Christmas steam up.
http://www.nmes.org/



I've used standard bar stock size to eliminate milling along with a piston valve, the fly wheel can be a standard 4" Stuart wheel or a fabricated one, I will also use lower cost material avoiding as must has posible copper based alloys.

Any way thats enough of that lets get on with the job,

You will need a small lathe an 1/2 decent drill with a good drill vice and some way of accuratly marking out like this



Just a cheep dig caliper with the legs cut back to form a set of odd legs

First Up the steam chest from 5/8 square ally. Cut a chunk off the bar face off to length in a four jaw and mark out the position for the piston valve.



The back into the four jaw and using a wobble bar set the centre pop running true



Deep centre drill then to avoid the use of expensive reamers drill through with a 5.9mm or a 7/32 drill this will cut over size and make the hole near to dam it 6mm, if the bar you're going to make the piston velve out of is a bit tight just lap it down for a nice slide fit.



Then accuratly mark out the position for the inlet ports don't centre pop them, into the drill vice and line up with a sticky pin this is just a pin held onto the chuck with platercene and nudged until it runs true. Clamp the vice to the drill table



The start with a small centre drill then follow up with a 3mm drill, don't unclamp the vice from the table just losen the jaws and slide the job along to line up the second hole again with the sticky pin a drill that one, do the same with the exhaust holes.



Mark out for the position of central inlet fead, and the 2mm dia clamp down holes, you don't need the sticky pins to line these holes up as their positions are not as critical just use the centre drill.



Thats it job done, just a few more holes to drill in it off the inlet and rod gland fixtures when they are made.



The deburing tool is what my late Dad made I can tell he made it as it's got his personality writen all over it.

Stew

A little bit of clearance never got in the way

Offline b.lindsey

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Re: Potty Lads and Dads Mill Engine
« Reply #1 on: April 15, 2013, 02:22:56 PM »
This is a great idea Stew and I like the name of it too!!  Looking forward to seeing it progress as I do with all your threads.

Bill

Offline steamer

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Re: Potty Lads and Dads Mill Engine
« Reply #2 on: April 15, 2013, 02:24:49 PM »
Looking forward to this Stew!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Bearcar1

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Re: Potty Lads and Dads Mill Engine
« Reply #3 on: April 15, 2013, 02:48:46 PM »
BRAVO! Stew. That is a terrific name and a marvelous idea in the title of the project. BRAVO! :praise2:


BC1
Jim

Offline NickG

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Potty Lads and Dads Mill Engine
« Reply #4 on: April 15, 2013, 04:18:10 PM »
Nice 1 Stew, a great start. Will definitely be watching.

Offline Stilldrillin

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Re: Potty Lads and Dads Mill Engine
« Reply #5 on: April 15, 2013, 04:55:46 PM »
I'm watching Stew!  ;)

Love your Dad's deburrer!   :Love:    That's given me an idea.......  :thinking:

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline sbwhart

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Re: Potty Lads and Dads Mill Engine
« Reply #6 on: April 15, 2013, 05:09:51 PM »
Thanks for youre interest Chaps

Dave:- the handle is made from a scrap firing plug from a 30mm cannon shell, that how I know he made it  :mischief:

Stew
A little bit of clearance never got in the way

Offline Stilldrillin

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Re: Potty Lads and Dads Mill Engine
« Reply #7 on: April 15, 2013, 07:04:11 PM »
Thanks for youre interest Chaps

Dave:- the handle is made from a scrap firing plug from a 30mm cannon shell, that how I know he made it  :mischief:

Stew

Aaawww. Stew! That's done it!   :hellno:

I've been looking all through my scrap pile. Not got one er them!  :facepalm:

Got a handle from a Cincinnati miller! Will that do instead?   :thinking:

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline sbwhart

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Re: Potty Lads and Dads Mill Engine
« Reply #8 on: April 15, 2013, 07:12:08 PM »
Thanks for youre interest Chaps

Dave:- the handle is made from a scrap firing plug from a 30mm cannon shell, that how I know he made it  :mischief:

Stew

Aaawww. Stew! That's done it!   :hellno:

I've been looking all through my scrap pile. Not got one er them!  :facepalm:

Got a handle from a Cincinnati miller! Will that do instead?   :thinking:

David D

Yah go on then it'll just about do  :Jester:

Stew
A little bit of clearance never got in the way

Offline sbwhart

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Re: Potty Lads and Dads Mill Engine
« Reply #9 on: April 16, 2013, 07:41:25 AM »
A 3D CAD animation of the engine, that my friends son did


Enjoy

Stew
A little bit of clearance never got in the way

Offline NickG

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Potty Lads and Dads Mill Engine
« Reply #10 on: April 16, 2013, 08:58:55 AM »
Awesome!

Offline AussieJimG

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Re: Potty Lads and Dads Mill Engine
« Reply #11 on: April 16, 2013, 11:41:12 PM »
I have not seen an odd leg digital caliper before. How do you use it Stew?

Jim

Offline sbwhart

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Re: Potty Lads and Dads Mill Engine
« Reply #12 on: April 17, 2013, 06:16:06 AM »
I have not seen an odd leg digital caliper before. How do you use it Stew?

Jim

Jim:-  Say you want to scribe a line 10mm from an edge you just zero the caliper then set it to 10mm then with long leg against the edge you use the short leg to scribe the line.

Just buy a cheap digi caliper, the legs are too hard to cut with a saw so cut them back using thin cut off discs you get with dremels, and finish off on the hand grinder.

The foot at the other end is something I made so that you can use it as a depth gauge.

Stew
A little bit of clearance never got in the way

Offline AussieJimG

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Re: Potty Lads and Dads Mill Engine
« Reply #13 on: April 17, 2013, 08:55:14 AM »
Thanks Stew, I have used the caliper in that mode but did not think of modifying it to improve the accuracy. And the Depth bit at the other end looks useful.

I have a spare caliper, it is likely to be modified in the near future.

Thanks again for the hints.

Jim

Offline sbwhart

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Re: Potty Lads and Dads Mill Engine
« Reply #14 on: April 17, 2013, 10:46:24 AM »
No wories Jim  :ROFL:

A couple more bits finished off this morning up bright and early before six and a good 3 1/2 hrs in the shed, while it was quite (heaven   :mischief:)

Whilst i'd got the four jaw in tha lathe I quicly made the square base bit this was just a simpler vertion of the steam chest, so no pics.

Then got started on the end covers, I made both covers at the same time but you may choose to make them one at a time.

First job chunk of 35mm ally bar in the lathe face off and rough out the OD then just mark the centre with a small centre drill, black the end up, and using as et of deviders mark the PCD for the four clamping down bolts, then to mark the holes position on the PCD using one of those digi protractor thing stick it onto one of the jaws (they are magnetic) zero it up and scibe a line across the centre, rotate the chuck so that it reads 90 and scribe another line across thats it you've got the hole positions marked out, no fancy kit required. If you havn't got a digi thing you can do the same trick with a spirit level.



Then don't remove it from the chuck take the chuck off the lathe and clamp it to the drill table locate on the position centre drill then drill to required depth I drilled it deep enough to make both.



Put the chuck back onto the lathe, and turn the 16mm register for the cylinder, I did this with a part off tool then zeroed the dial and cut a groove down to the zero in the position for the second cover.



Part the First cover off.




Then turn the features for the piston rod gland drill and tap M6 and part off



Job Done





Stew
A little bit of clearance never got in the way