Simple IC engine

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speedhound

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What is the simplest IC engine that can be built from stock and how difficult is it to bulid and get running? Have seen Jan ridders simple two stroke but some people say its hard to get going.

Thanks
 
I vote for the Nemett 15s, its a very nice simple engine to build in either water or air cooled versions and all from bar stock. It runs well and has a long series of how to make it in the Model Engineer magazine.

example:
ne15s1.jpg

 
I did a Webster as my first I/C. I think because being the plans were complimentary on the internet, I could study them for awhile before getting all in. Very satisfied with the results with some self doubt along the way, I am now comfortable taking on I/C. Read about my experiance as a novice builder here! :) http://www.homemodelenginemachinist.com/index.php?topic=8256.0
 
How about Gingery's Atkinson cycle, build is described step by step and runs easily and very well.
Book is available from Lindsay's.

Peter
 
Knowing what machines are at your disposal and the level of confidence/experience you possess in machining would have a direct impact on the answer to your question. If one has free access to a lathe and milling machine, and has the skills to run them, it greatly increases the choices that one has to choose from. Probably the 'simplest' engine option would be "The Webster" as has already been mentioned. Those drawings can be accessed in the downloads section on this site. The Jan Ridder's engines are relatively simple and straight forward as well (although they are in metric format) and should not present any more difficulties to get running if all of the fits are held to a close tolerance. The same can be said for The Webster, or any engine for that matter. If the valves are not painstakingly attended to in terms of getting them to seal 100% and attention to the piston to cylinder wall isn't properly executed, any engine, no matter how simple or complex in mechanical nature will be next to impossible to get running. Best of luck.

BC1
Jim
 
The simplest engine is probably going to be a 2 stroke. Crankshaft and piston ports do all the valving, Model airplane fuel and glow plug are cost effective and all you need to get it started is a 1.5 Volt battery. Carb can be a fixed carb with a simple spraybar. Check ou the .60 2-stroke plans I uploaded a while back.

Oh - and another plus - no gears.
 
Thanks for replys, i do have machines cnc and manual, i have built Jan Ridders twin cyl vacuum engine with internal valves and am trying to get it going at the moment but not sure if it will go :-\. I have no experience with an IC engine and was just woundering if it would be possible for me.

Thanks
 
Hi Speedhound

You may find my experience building Jans Simple Two Stroke of interest.

http://start-model-engineering.co.uk/category/jan-ridders-simple-two-stroke/

As you will see I did have initial problems to get it to run. After increasing the compression with a modified piston and cylinder head the engine now starts and runs without any problems. I feel that for anyone taking a first step into IC engines should opt for a 2 stroke for a better chance of success.

John
 
What is the simplest IC engine that can be built from stock and how difficult is it to bulid and get running? Have seen Jan ridders simple two stroke but some people say its hard to get going.

Thanks

I have just got my Jan ridders DEBBIE running easy to start and run on model engine glow plug fuel and a spray bar fitted. https://youtu.be/KpeuXRtJy5I
 
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Thanks for replys, i do have machines cnc and manual, i have built Jan Ridders twin cyl vacuum engine with internal valves and am trying to get it going at the moment but not sure if it will go :-\. I have no experience with an IC engine and was just woundering if it would be possible for me.

Thanks

Mate of mine is retired secondary school manual arts teacher ( tech drawing, metal and woodworking) In his time at a local high school he designed, built and made available to a class of kids each year to build a single cylinder 4 stroke engine. Not from extrusions but from a set of castings he made.

He passed his knowledge to several replacement teachers over the years and to this day that same engine design is being built. 15cc with provision for water cooling, can initially be poppet valve and for some kids who were a little more progressive, inlet valve cam and mechanism could be added at a later date. I have some castings here somewhere so maybe get a photo for you. Note that design also allows for a "built-up" crankcase if you so desire.

Many of his former students who are now well established in their careers,still at times comment on this time at the school.
One thing is for certain, it sure beat knocking up a dustpan with rivets that for the most part was chucked in the bin when kids brought them home and the most remembered time was when Johno and his mate received a clip in the ear for sword fighting with a file.:eek:
 
Mate of mine is retired secondary school manual arts teacher ... I have some castings here somewhere so maybe get a photo for you. Note that design also allows for a "built-up" crankcase if you so desire.

Do you have plans for this engine that can be shared? I'd be interested in maybe keeping your mate's legacy going and having a go at building one, possibly even casting the relevant bits if it's not too complicated. All I ever built in manual arts was a brass 'sprinkler' from a bit of 3/4" bar and a short length of steel rod...
 
I tried making a Webster once. Apparently I'm the only one in the universe that wasn't able to get the damned thing to run.

I had good piston sealing, but I never could get my valves to seal no matter how many times I tried, re-made, and lapped them.

There must be some technique on poppet valves that I just couldn't figure out.

Eventually I gave it away to a friend and wished him the best of luck. I went back to steam and hot air engines.

Does anyone have a primer on how to properly make and seat poppets?

Thanks

...Ved.
 
Does anyone have a primer on how to properly make and seat poppets?

There's quite a few different techniques around. For me, I cut the valve stem down in sections around 8-10mm long to reduce deflection, til the whole stem is around 0.01 - 0.02mm oversize, then finish to size with wet and dry. Then I cut the angle on the head at 45 degrees (or somewhere close is good enough) and part the valve off with at least an inch-or-so extra material on the head end, as a handle to hold on to for lapping. Repeat for however many valves you need, plus a spare or two, and another to become the seat cutter - this one with at least a couple of inches extra material. Doing them all without changing setup in the lathe is critical to keep all angles the same.

The valve seat cutter needs some milling to make the 'head' have some cutting teeth (plenty of examples on here, I could dig one up if you need it) then operated by hand to make thin seats in the valve cages. Then it's a matter of lapping each valve into its' individual seat - this is the bit where opinions vary wildly.

What works for me, as long as the valve seats and heads are well made (smooth and shiny), is a generous amount of standard white toothpaste and revolving the valve through 180 degree by hand while applying a little bit of force on the seat. Every 30 seconds or so I poke the toothpaste around so a fresh bit is covering the lapping area and rotate the valve 90 degrees then start again. Repeat that maybe 4-5 times and it should generate a good enough seal to fire. Once the engine starts firing the valves improve their sealing quite quickly.

The only time I've had real trouble getting valves to seal was my first engine where I applied my full size techniques and used a rotary drill in a vain attempt to lap the valves in. They absolutely refused to seal and I eventually remade both the valves and the cages.
 
I've mentioned this before somewhere but anyhow....
We have found the only successful way to get a good seal on valves ( repeatedly and first time around) is to cut both the valve and the seat insert at the same time without moving the adjustment on the lathe.

I will ask George about drawings etc. sometimes he has committed his work to the magazine for publishing and that sort of ties it up there.
Below are the castings.
Maybe he would be prepared to sell a set.
For size comparison, the water cooling barrel section is around 55mm square x 45mm high.
Meant to put a ruler in there but the camera battery went flat. Try again later.

Cheers Jorgo

DSCF2999.jpg


DSCF3000.jpg
 
As can be seen by the above, the castings he does are free of any defects (blowholes etc)
Managed to achieve this by many years of trial and error and a tad of good luck on the day.:)

George presented me with these castings a while back, just haven't managed to get around to building it at this stage.
We tend to trade expertise, one bit for another.:cool:

See if I can get a photo of the completed engine to post here.

Cheers Jorgo
 
Went to see George today and he gave the ok to put all the plans, write up and photos in here.
Apparently no magazine agreement but he does ask that people send in their versions/ build.
We all like to see the way our efforts spread out worldwide and are recognised.

So........... do I post the stuff here or make a new thread.???

Just sometimes for whatever reason, some get a bit funny like that on these forums.

Presently have all the plans scanned and will combine in a single file ( about 1.2meg)
Hope a file that size is allowed.
Edit....ok...just found file in pdf up to 3.8meg so no worries.

I have to redo the construction notes as the scan came back HUGE....:)

Cheers Jorgo
 
I'm not 100% sure but I think there's a limit of around 2mb for attachments to a post. However, if you go to the downloads section - http://www.homemodelenginemachinist.com/downloads/ - there is a button at the top to 'Add a File' and you should be able to upload to there. If you don't want to do that you could either split it into parts for uploading within a post or upload it off-site to somewhere like Dropbox and provide a link.

BTW - those castings look great. Looks like I'll have to investigate how to make cores though.
 
As the heading states, I made an error when I said about George's design being 15cc as it is indeed 25cc.

Not that one wouldn't be able to rehash and make it 15cc though. Just make the hole a bit smaller in the top. :p

Have the plans here....sorry but when they were joined it came back with the drawings all sideways. Not sure where I stuffed up but it can be easily rectified.
Open each main set, right click somewhere in the first drawing and, rotate.
Well yes, the cover drawing is a-up but the rest seem ok....sorry for that.

Pdf files are ....NewC_21 (cover to page 21) and New22_34 (pages 22 to 34)

This is just the drawings at this stage. I tried to scan the construction notes but the files came out HUGE so George is looking on his old PC for the originals in doc (word) files. They should be a respectable size.

He is not interested in doing any castings as time runs away with other projects he has in mind. What I will do though is see if I can get a couple of photos of the patterns for the castings and for the cores as well.

Cheers ....Jorgo

View attachment NewC_21.pdf

View attachment New22_34.pdf
 

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