Tentative first Four stroke

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Joined
May 8, 2023
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Location
Stow on the Wold, UK
My first post after watching for some time.

UK based.
I'd very much welcome guidance and moderation on ambition.

I've made steam engines for quite some time, both stationary, traction engines and railway locomotives.
I've never made an IC engine, being somewhat daunted.

I'd like to give it a go.

I've downsized my equipment over the years, following downscaling on engines.
I've a Warco WM180: with DRO's, 90mm centre height ~3.54"

Supplemented by a Peatol (Taig) CNC micro Mill, with long bed and manual rotary control as well as CNC.
The usual machine tool accessories, but I've yet to decide on rotary table, for the Mill rather than the lathe methinks.

I've searched the usual sources of engines.
I'd really like to keep it simple, anticipating enough new challenges with camshafts and ignition.
Ideally I'd like a twin, boxer, or whatever, but probably more realistic to start with a single.
I'm at a loss:
Those available from Hemmingway seem wonderously aged. The recommended beginners is the Westbury Kiwi mk2 harks back to 1935, revised upwards. The castings cost more than purchasing a modern 4 stroke.
The Kiwi Mk2 - E T Westbury - hemingwaykits.com

I think I've seen a couple of boxer twins, machined from stock.

Drawings are fine. However, drawings supplemented by guidance and machining notes would be a huge help for a first 4 stroke fabrication. Too many jigs or tooling manufacture would put me off.
Simple rather than elegance or beauty.
I'd really welcome some guidance as to where to start, and source of drawings, castings, guides.

Hope that you can start me off

Robin
 

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Hi .
Welcome to the group !

Too many jigs or tooling manufacture would put me off.
Simple rather than elegance or beauty.
I'd really welcome some guidance as to where to start, and source of drawings, castings, guides.

Hope that you can start me off

Robin

Let's start with as simple a 4-stroke engine as possible, like a webster engine. .
It will be a great engine if you try to make it beautiful...
 
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Robin, seems like we have followed a similar path in model engineering, several locos, stationary engines and hot air engines under my belt before embarking on petrol engines my first was a Whippet but even these can be bought from China quite cheaply now. I agree with a bar stock engine as a first as it's not too expensive on practice parts. You could also go on then to Len Mason's Mastiff as I have seen them built from bar stock although mine was from Hemingway's castings. Mine has been a troublesome build but I've learnt and still learning from it trying to set it up in a loco. Whatever you choose you will enjoy the build and it's not as difficult as you may think.
Brian
 
Robin, seems like we have followed a similar path in model engineering, several locos, stationary engines and hot air engines under my belt before embarking on petrol engines my first was a Whippet but even these can be bought from China quite cheaply now. I agree with a bar stock engine as a first as it's not too expensive on practice parts. You could also go on then to Len Mason's Mastiff as I have seen them built from bar stock although mine was from Hemingway's castings. Mine has been a troublesome build but I've learnt and still learning from it trying to set it up in a loco. Whatever you choose you will enjoy the build and it's not as difficult as you may think.
Brian
Thank you, Brian, that's encouraging, and congratulations on your tenacity with the Mastiff
 
Another one to consider is Malcom Stride's Jaguar which is a barstock single, there is also an inline twin of the same design called the Bobcat. Before his death Malcom intended the basic head and cylinder of this design to be use in other formats, I've done an opposed twin and there is also a 4 cyl boxer version

It can be made as an air or water cooled engine and unlike the old designs or those from the US is in metric so easily and cheaply sourced bearings, gears etc. A few back issues of Model Engineer will get you drawings and build article.

This is the inline twin which more people tend to make, the single is just one of them cut in half

me4437_p300.jpg


My opposed twin Ocelot

DSC02498_zpsiklqtf8q.jpg
 
My first I.C. engines were from plans from UpshurEngineWorks.com
The plans are very good and include instructions and building tips.
Miniature I.C. engines can be tricky to get running, but it's a great feeling when they first start!
Scott
 
Welcome to the forum!

Another vote for the Webster here. In addition to the plans-as-drawn, it is simple enough to modify to suit materials at hand (e.g., metric bearings). I did a build log a couple of years ago in which I modified and posted the plans for metric bearings and module 1 gearing (even though I am in the US, it is easier to source inexpensive metric bearings and module gear cutters). I made a few other changes as well to suit my materials, notably using steel in place of the aluminum called for in the frame and several other components, simply because I have access to a good bit of scrap steel, but very little scrap aluminum. If you are interested, the build log and plans are here: Introducing ... the "Steel Webster"

Let us know what you decide, and don't hesitate to ask questions - lots of wisdom on this site, freely shared!
 
The Zero-Six from Model Engine Builder is a little bigger, has the hit and miss mechanism, all bar stock. It is 1-1/4 inch bore if I remember correctly (might be 1-1/8") The picture to the left is mine, the red one in Jasonb's heading is his. There is a lot of latitiude for how you think it should look. Plans should be available from MEB, maybe "mrehmus" can help with that.
It's the most consistent runner I have.
Make the flywheels bigger than the plans say....
Doug
 
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Another one to consider is Malcom Stride's Jaguar which is a barstock single, there is also an inline twin of the same design called the Bobcat. Before his death Malcom intended the basic head and cylinder of this design to be use in other formats, I've done an opposed twin and there is also a 4 cyl boxer version

It can be made as an air or water cooled engine and unlike the old designs or those from the US is in metric so easily and cheaply sourced bearings, gears etc. A few back issues of Model Engineer will get you drawings and build article.

This is the inline twin which more people tend to make, the single is just one of them cut in half

me4437_p300.jpg


My opposed twin Ocelot

DSC02498_zpsiklqtf8q.jpg
Fabulous, something that I would wish to aspire. I'll do a search to see if there are any build threads of somewhere to get a peak of the drawings.
 
My first I.C. engines were from plans from UpshurEngineWorks.com
The plans are very good and include instructions and building tips.
Miniature I.C. engines can be tricky to get running, but it's a great feeling when they first start!
Scott
I'd come across these, but couldn't see anything of how simple or complex the drawings are
 
Welcome to the forum!

Another vote for the Webster here. In addition to the plans-as-drawn, it is simple enough to modify to suit materials at hand (e.g., metric bearings). I did a build log a couple of years ago in which I modified and posted the plans for metric bearings and module 1 gearing (even though I am in the US, it is easier to source inexpensive metric bearings and module gear cutters). I made a few other changes as well to suit my materials, notably using steel in place of the aluminum called for in the frame and several other components, simply because I have access to a good bit of scrap steel, but very little scrap aluminum. If you are interested, the build log and plans are here: Introducing ... the "Steel Webster"

Let us know what you decide, and don't hesitate to ask questions - lots of wisdom on this site, freely shared!
An excellent build link, more than informative, and useful as being in the UK, sourcing bearings in metric is easier.
I presume that the gears may be available in the UK too, as I've not a rotary table now gear hobbing
 
The Zero-Six from Model Engine Builder is a little bigger, has the hit and miss mechanism, all bar stock. It is 1-1/4 inch bore if I remember correctly (might be 1-1/8") The picture to the left is mine, the red one in Basil's heading is his. There is a lot of latitiude for how you think it should look. Plans should be available from MEB, maybe "mrehmus" can help with that.
It's the most consistent runner I have.
Make the flywheels bigger than the plans say....
Doug
Thank you, I'll look up the thread
 
Thank you all, I'm delighted with the positive responses and encouragement.

I'd more or less settled on the Webster 4 stroke, especially with the tantalizing opportunity that some bits which I haven't tacked before are commercial.
I've downloaded the drawings. It looks that I've the 'metric' version.

I wonder if I could ask for a little more help.

I'm in the UK. I've a list of supplies that I've used for the this and last century, but obviously for steam.

I've spent a few hours looking through the drawings, and searching for supplies
First observation:

The 'metric version'.
I'm confused. It seems that our esteemed author has simply converted imperial dimensions to metric equivalent:
I've attached a couple of sheets, and as an example sheet 9 showing the gears and ancillaries:

Cam gear washer:
OD 12.7mm
ID 6.35 mm
now these are 1/2 inch and 1/4 inch.
also a reamer of 7.94mm ~5/16

I'm used to working with imperial but my tooling is metric and used to converting to nearest. Reaming to 7.94mm is difficult, I have a 5/16 reamers. Seems an odd method of transcription.

Staying with sheet 9 attached.


20230825_162918.jpg


Upper CAM gear stock drive products A 1B 2-N32048
Discovered the nomenclature for spur gears and this is a 32DP 48 tooth, with hub

No idea how to decode the other dimensions.

Ditto A 1C 2-N32024

I'm having difficulty understanding what I'm looking for. It's probably just ignorance (unfamiliarity) with terminology. I'm sure that they're abundantly common sizes. What are they, how are they more simply defined, where can I find them? UK sources

Sheet 21 attached.

None of the additional items make any sense when searching for them.

Piston rings as described: The source doesn't exist any more. Where in the UK?

As to points, condenser, I'm sure pretty standard items, but again the sources quoted don't exist..
Yes I could use Vitol rings, good for steam, but advised only viable for short runs
Yes I could fabricate the rings.
Yes I could fabricate the spur gears, if I know the dimensions, source a suitable (Sherline probably) rotary table for the Peatol/Taig mill, suitable tooling.


Or perhaps the original imperial drawing are more accessible.
 

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That's is the problem with what some people call metric conversions they simply do a mathmatical conversion or hit a button on the CAD package and get metric dimensions to imperial sized parts. I do a proper conversion when I redraw an engine. Though you may have the imperial version of the drawings but what I have seen of the "metricated" one it only alters gears and bearings.

EDIT you need Awake's metricated drawing. Still mostly imperial but the stock gears are metric see here

So your 32DP imperial gears would be converted to MOD0.8 and PCD adjusted to suit and have a metric hole eg 8mm not 5/16"

Those gear numbers are a makers ref such as Boston Gear in the US and include things like bore and size/type of boss if any

Rings are best done with Viton, should run for hours on a hit & miss engine. Hard to find off the shelf CI metric rings in the UK but common imperial like 3/4" and 1" available from Reeves or Stuarts

My suggested engine is fully metric not an imperial conversion in sight and easily available MOD gears

I'd stick a modern CDI ignition on it rather than old points and a big coil
 
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Thank you Jason, I'll stick with the imperial, and approximate my drills accordingly. My reamers are all imperial.

I'll search out the imperial version, and many thanks
 
An excellent build link, more than informative, and useful as being in the UK, sourcing bearings in metric is easier.
I presume that the gears may be available in the UK too, as I've not a rotary table now gear hobbing
Thanks! I used Module 1 gears, but I cut them myself - it is also easy to source inexpensive import module 1 gear cutters here. Not the best quality cutters, but adequate for the purpose. I would hope there would be a supply of module gears readily available there.
 
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