I think I can squeeze in another project before getting back to the Class 22, I am going to have a go at a Jasons MkII version of the Jowitt Popett Valve Engine.

I think Jason said it is approximately 30% larger than the original having a 24mm cylinder bore. Fortunately Jason has one of his excellent build threads complete with drawings here on the forum so that is a real bonus.

I really like the look of the engine and its a bit more advanced than the little Muncaster oscillator I have been building so a bit of a step up so to speak.

Still waiting for the flywheel to finish the oscillator so having some material to hand I made a start on the Jowitt side frames this morning, going well so far.

Thanks Jason, I did spend a fair bit of yesterday reading your build thread (twice) and studying the drawings to make sure I was happy which I am.

You probably noticed that I did live a bit dangerously today though, I should have set the frames up a bit further out of the vice. I was half way through cutting the large rad when I thought I was going to crash into the vice. I checked the dimensions and fortunately I cleared the vice at full rad buy a gnats whisker about 0.6mm..

Edited By Ron Laden on 16/02/2020 16:26:36

Edited By Ron Laden on 16/02/2020 16:29:09

Very nice Jim, I hope mine turns out as well.

I think it a really nice looking engine, the shapely cylinder block and the twin flywheels. Also watching Jasons videos it sounds good to.

Ron

The side frames are just about there, still need to machine the 3.6 degree angle to the ends and sides. I have sent off for a digital protractor, I have been meaning to get one for a few weeks so now is a good time.

I machined most of the side frames with the ARC 25mm two insert end mill. I have been using it a lot lately, very good should you need to remove a fair amount of material and the surface finish is excellent, really impressed with it.

Thanks Jason, if I had thought about it a bit more I should have realised that the angle is only cosmetic so close enough will be ok. I will give it a go in the morning.

Ron

Thanks guys but maybe my description is wrong, I dont mean a sprung tapping guide the ones I have seen are a length of bar, I,m guessing but maybe 6-8 inches with a small sprung centre. Used with a DTI in centering a workpiece in the 4 jaw, you have a picture of one Jason in your build thread when doing the cylinder..?