Lads and Dads Mill Engine

[Stewart HartParticipant @stewarthart90345]

A simple engine that can be made with limited equipment

[Stewart HartParticipant @stewarthart90345]

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

The engine is design so that a father/grandfather and his son/daughter could make it with limited equipment, lathe a resonable quality pillar drill and drill vice.

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.

An accurate method of marking out is required something like this

Its just a cheap digcalipre with the legs cut back to form an odd leg, the lump at the other end is just a foot I made so it could also be used as a depth gauge.

I've made a start on the valve chest

I'll add a few more pictures as work progresses

Stew

[Thor 🇳🇴Participant @thor]

Hi Stew,

looks like an interesting project, any chance you can post drawings?

Thor

Edited By Thor on 15/04/2013 17:40:30

[Stewart HartParticipant @stewarthart90345]

Hi Thor

I'm working from an incomplete set of drawings I've already found a few mistakes, and I'm changing things as I spot room for improvement, I'll be writing it up so hopefully it will be published in the mag.

Thanks for your interest.

Stew

[Stewart HartParticipant @stewarthart90345]

A little more progress got the cylinder and covers along with the valve chest and base nearly completed

Stew

[Stewart HartParticipant @stewarthart90345]

This is how far I've got so far, its progressing quicker that I thought.

Stew

[Rob keevesParticipant @robkeeves73950]

Can wait to see this in the mag, young Alex will love making this with daddy. Fab idea Stewart.

[Stewart HartParticipant @stewarthart90345]

Its seems to be comming together very quickly, i had a sort delay waiting for some ally plate to make the engines bed plate from.

Any way this is it so far, the fly wheel is a 4" dia Stuart wheel that I decided was too small for another engine I was building, for this one I think I may fabricate a fly wheel up that will be more in keeping with the origonal.

[_Paul_Participant @_paul_]

Hi Stew, engine build looks great,

I have a question tho how is that foot mounted on the Caliper?

Regards

Paul

[Stewart HartParticipant @stewarthart90345]

Posted by _Paul_ on 27/04/2013 02:42:37:

Hi Stew, engine build looks great,

I have a question tho how is that foot mounted on the Caliper?

Regards

Paul

Hi Paul

 

Thanks for your interest

The foot is made from a chunk of mild steel I simply milled a groove across it to take the caliper, and then so the foot would sit perfectly square on the caliper I took a light skim ocross its base without removing the it from the mill first, I then drill and tapped a hole across the foot opening up half its depth to the clearance size, I then drill a hole in the middle of the groove and put a saw cut into it, this made it into a pinch clamp so that it could be fixed to the caliper, the squence of pics should make this clearer.

If the interest is there i could submit a short article for the mag.

 

 

Edited By Stewart Hart on 27/04/2013 06:41:01

[_Paul_Participant @_paul_]

Hi Stew, thanks very much for the pics and I think it's a great idea for an article.

Regards

Paul

[Sub MandrelParticipant @submandrel]

Looking good so far Stew.

Neil

[martin perman 1Participant @martinperman1]

Stewart,

What an excellent Idea for a set of calipers, must see if I have a piece of metal to make a foot. Why did you shorten the caliper jaw.

Martin P

[Stewart HartParticipant @stewarthart90345]

Hi Martin

So they could be used as a set of odd leg calipers, for marking out.

Stew

[Sub MandrelParticipant @submandrel]

Hi Stew,

Just a thought, but when I was starting my problems were mostly a lack of small thing: no reamers, very few taps, no mill/vertcal slide, only 1/64" stepped drills and a few metric standard sizes.

Are these the sort of limitations you are allowing for? I assume the small cap-head screws are oneresult of this approach? Might be worth mentioning that 50 M3 countersunk screws from Screwfix go a very long way, and are quite close to 5BA. Ideal for any hidden fixins, or those which can be filled later.

Neil

[Stewart HartParticipant @stewarthart90345]

Posted by Stub Mandrel on 28/04/2013 18:03:22:

Hi Stew,

Just a thought, but when I was starting my problems were mostly a lack of small thing: no reamers, very few taps, no mill/vertcal slide, only 1/64" stepped drills and a few metric standard sizes.

Are these the sort of limitations you are allowing for? I assume the small cap-head screws are oneresult of this approach? Might be worth mentioning that 50 M3 countersunk screws from Screwfix go a very long way, and are quite close to 5BA. Ideal for any hidden fixins, or those which can be filled later.

Neil

Hi Neil:- thanks for your input

Yes thats the sort of things I'm trying to deal with, I've used metric threads throughout, these being the industrial standard taps and dies and screws are relativly cheap as you have pointed out. I've also kept away from copper based alloys for the main bits using ally and mild steel, I have resorted to brass and stainless for some of the smaller parts as I have plenty of this in my stash but mild steel would be just as sutable.

When I write it up I'm going to include a bill of material stating size and quantity of material required along with thread sizes and with alternative sizes Imperial and unified

And a list of dills required maybe or I may just say set of number drills.

I drew it up in metric but amazingly I found suppliers to the model engineering comunity don't stock metric size material so I had to resort to imperial equavalent.

The fly wheel is causing me some problems I have a 4" Stuart flywheel, but I want to fabricate a wheel out of 4" thick wall steel tube and 1/4" plate.

It would be nice if one of the supliers could supply a kit of material and fixing: in a similar way they do for cast kits. Hint Hint.

Stew

[1Participant @1]

I also have found difficulty sourcing metric sized stock. I was at a dead end looking for 4mm thick brass flat until I tried M Machine who cut me a piece to the size I needed at a very reasonable price and with fast delivery. Usual disclaimers apply.

Certainly, imperial sizes are more common among the usual model suppliers but working in metric is still achievable.

Jim

[Sub MandrelParticipant @submandrel]

OK Stew, I have to ask. What on earth is the lump at the left of this picture and where does it fit?

Neil

[Stewart HartParticipant @stewarthart90345]

Hi Neil

It doesn't fit anyware:- its a deburing tool my late Dad made )

Its made from a drill stub and a scrap component from the production line he was in charge of.

I just like using it, I have quite a few tool he made and they kind of remind me of him, as he always seemed to get a little of his personality into things.

Stew

[Sub MandrelParticipant @submandrel]

Ah! I thought it was a very short screwdriver! I might copy that. I have a few things in the same vein – tiny, very worn pliers that belonged to my (coppersmith) grandfather, for example.

I hope something I make has a similar fate.

Neil

[Stewart HartParticipant @stewarthart90345]

Posted by Stub Mandrel on 29/04/2013 20:06:19:

I hope something I make has a similar fate.

Neil

Me too

When I drew the engine up I drop a bit of a cod, in that I had made no provision for adjusting the valve events, I did a bit of head scratching on how to correct this came up with some weird and totaly impractical solutions, so had a look through the pictures i took of the Bolton engine to see what they did and it couldn't be simpler:- they just link the eccentric rod to the valve rod by a simple link that could be slid along to make the adjustment.

This is my take on the system

Works fine though a little over scale but thats just one of the compromises you have to make. I've losly assembled the engine up and roughly set the valve events and she winds over nice, I'm waiting on the delivery of some steel tube to make the fly wheel so in the mean time I've been working on the bed plate and a mounting plynth, it was common for this typ of engine to be mounted on a stone plyth, so I fabricated on up from chip board.

This is very much a suck it and see job, I'm planning on felt tipping the mortar line in and stipling it over with thin emulsion paint followed by a thin coat of mat laquer to seal thing.

If any one could give me a few pointers on this it would be very apreciated.

Stew

[Ian S CParticipant @iansc]

For one of my hot air engines I used a similar method of construction, mine is 6" dia, I collect old brake drums, and discs, and one disc brake was top hat shape, just over 6" dia x about 1.5" high, so cut the brim/disc off, and the top/flange, the cylindrical bit left about 3/8" thick. The section with the spokes was made of 3/8" plate, this is pressed into the rim, and also held with six counter sunk screws through from the outside of the cast iron rim, on this one the hub is brazed in , on later flywheels the hub is held in place with shaft lock adhesive. The motor that this flywheel is on can run up to just over 2000rpm running with out a load. Ian S C

[Stewart HartParticipant @stewarthart90345]

Hi Ian:- I always sneek a look in the scrap box at garage I have our cars serviced to see if they have anything of use,(always ask before you take). Do you remember the days when you could service a car yourself without plugging it in to a computer.

Whilst waiting delivery of some material to make the fly wheel I had a look round our local hobby craft shop they had a sale on so i pic this lot Its some water based wood stain and some felt tip pens, the felt tip pens we're useless all dried up but the wood stain was ok, to mark the cement line i just mixed some of the wood stain with some white emulsion and put it on with a thin brush. Then to seal it I watered down some PVA and brushed it over. I don't think it looks too bad. Just taken delivery of the fly wheel steel so its just some M2 studding I'm short of now Stew:———— this site is playing up

[Ian S CParticipant @iansc]

One place to get reasonably thick walled steel tube, car starter motor, or old type car generator. If you want to collect it, I'v got an old cylinder liner, about 4.5" dia, think its around 3/8" thick, think it came out of an old tractor. Ian S C

[Stewart HartParticipant @stewarthart90345]

Posted by Ian S C on 02/05/2013 12:26:50:

One place to get reasonably thick walled steel tube, car starter motor, or old type car generator. If you want to collect it, I'v got an old cylinder liner, about 4.5" dia, think its around 3/8" thick, think it came out of an old tractor. Ian S C

Thanks for the offer Ian and the tip as to where to look, but the posti had just dropped off a length of 100mm*4mm thick welded steel tube and some 1/4" plate fro the fly wheel, just waiting on some M2 studding but in the mean time its flywheel her I come.Thanks again Stew

Edited By Stewart Hart on 02/05/2013 14:47:18

[Author]

Posts