Member postings for Ron Laden

I was up for the dawn chorus this morning, turned the crankshaft, finished and fitted the crank arm, turned the crank pin and lock nut plus a pair of main bearings, all went well.

Starting a new project, I am keen at some point to build a Hit & Miss engine and was thinking of starting one but then thought it better if I get another engine under my belt first.

So I have decided to have a go at Jasons design of the Muncaster,s Simple Entablature Engine which he released just over a year ago and sized at 24mm bore. It caught my eye immediately thinking it an attractive looking engine with the four columns and the entablature, just looked a bit different to me.

I am about finished on the Jowitt, just waiting for some compressor fittings and seeing that I have the flywheel casting for the entablature I thought I would make a start.

I have turned the flywheel which didnt need much as it is such a clean and balanced casting plus I bored the wheel for a good fit to a piece of ground bar which will be come the crankshaft. I also turned the crank from a piece of round steel bar, just needs to go on the mill to cut the tapered sides.

Jason, would silver steel be ok for the crosshead guides or is it the wrong material, its the nearest size I have on the shelf. I have some 100 x 40 x 8mm pieces which I thought I could get down to size and most of the shape with the 25mm end mill, if its not suitable I will get some bright steel in.

Morning Jason, would appreciate your thoughts on increasing the crankshaft from 8 to 10mm its just convenience really. I have 10mm ground bar and my smallest boring bar will go down to 10mm. It would mean the bearings growing by 2mm but it looks as if the pedestals have enough meat. I would rather bore for the crank than ream, it would just look a tad heavier in the crank area but I don't think too much. What do you think..?

Ron

Well surely thats a sign of a quality casting, just started on the flywheel (waiting for a new compressor for the Jowitt).

I clocked up the inside of the rim or as near as for an unmachined casting and it took just 1.0 mm removed to clean and true the rim outer face and only 0.8mm to clean the rim side, I doubt it gets much better than that.

Another of your excellent build threads Jason, for those that have a go at your designs they really do get their hand held through the build, it's much appreciated we'll certainly from me at least.

My JDW version which I built was drawn with a single piston O ring but changed to two oil grooves, I see you have gone with 3 grooves and just wondered what your thinking was on that.

Ron

No Jason it has a M4 grub screw locked in there and I will fill over the top on finishing. Also the fitting threads are short of the cylinder hole.

Edited By Ron Laden on 03/04/2020 16:42:58

The Muncaster wheels arrived, amazed at how clean the castings are..excellent.

Made some further adjustments and I am really pleased with it, yes its a bit starved of air hence the need for a higher output compressor. It starts first time every time so the settings must be pretty close a bit more video below.

Thanks Jason, thinking of getting one of these, should do the job and quite compact can live under a bench.

Edited By Ron Laden on 03/04/2020 08:33:56

Thanks Clive/Jason, I think you are right it did cross my mind but thought it was the engine being tight and not set up correctly. The engine is now set correctly and spinning it over it feels really good, smooth and free so I,m sure it is now ok.

My compressor is an on demand type it doesnt have a tank, it is rated as 40psi and 0.8 cu ft per min. Using it to run the little oscillator it switched on and off but with Jowett it is running full time so I guess thats a sign that it is at its limit.

Anyway, now I know the engine runs ok I will sort a new compressor it will be good for shop use as well.

I dont want a largish type with a large tank, I dont have the room so would have to bring it into the shop when needed and then store it somewhere else.

I have found a bench type compressor with a 6 litre tank, 8 bar and 6.3 cfm I,m guessing that should be fine..?

I did try it without the O ring but couldnt get it to run, I,ve checked the springs and think they are ok.

A bit of handheld video below of what I have at the moment, it is certainly a bit better for some running. Going to give it some longer runs and see if it beds in some more. Despite the teething problems I am quite happy with it and hopefully can get them sorted.

p.s. apologise for the sound of the compressor, I need a longer airline to get it off the bench.

Edited By Ron Laden on 02/04/2020 16:06:45

Jason, I reset the eccentrics and I have the engine running but I only have one speed (slowish) but at least I have it running and have had it running for half an hour now.

I know the crank, big and small end are all good so I am guessing the O ring is holding back the speed, do they take much running in. I am hoping that once it gets easier I will be able to fine tune it and get variable speed.

Yes I have the holes plugged, how critical is the timing..?

Yes Jason when I flick it over it sometimes manages an extra rotation on its own as if its almost there. Also with the air on if I slowly turn it over I can feel what seems to be good compression as the piston approaches TDC..

Edited By Ron Laden on 01/04/2020 16:28:01

Having a tea break, I have been playing with the engine for over 3 hours and cant get it to run, something is amiss but I cant fathom what.

Jason, you were quite right re the piston, now the engine is assembled it feels really good turning the flywheel it is really smooth. A good flick of the flywheel and it spins about two and a half times but it doesnt stop abruptly, I know you said yours spins about six times but mine is not yet bedded in so hopefully it will improve.

Thanks Chris and thanks again for the flywheels it saved me a few pounds, much Ron

Ready for a test run just waiting for an airline fitting to arrive, first time setting up eccentrics I think I have it right but we will see. Should it run ok just a few small jobs before paint, fit and blend in the feet plus a bit more shaping to the base frame, make and fit an exhaust and a finishing cut to the flywheel rims.

Great stuff Jason good to see how the reverser works and I like the notches machined on the back face for the control lever, thats really neat.

I enjoyed making mine it makes up into a nice looking engine that runs well, would recommend it for anyone looking for a small project, doesnt take long though it took me 2-3 times as long as Jasons record time.

Mine doesnt have the reverser so I would say go with Jasons as the reverser adds more interest.