doubletop

Apologies, it has all gone a bit quiet here. I have been given another project and I need to make some progress on that, working out what needs to be done, getting things organised and getting the ball rolling. I don't like having more than one project on the go at once so this one will be parked for the time being

Pete

Quote from: Charles LamontThat all seems to be coming on very nicely. A most productive six months' work.

Charles

Thanks. It is interesting that you say that because I think I am being slow. In the past these projects have sort of consumed me and every day I'd be in the workshop as if I was going to work. This time I am deliberately taking it easy and at times have to give myself a bit of a talking to to get out there rather than making excuses. The problem I am finding with the lack of continuity is making silly mistakes and not taking into account something I had made a mental note of in a previous phase. Note taking has never been one of my strong points.

Pete

Quote from: Sanjay FAll the parts look great and the video of everything moving in unison is very hypnotic! 

Sanjay

Thanks

It is even more hypnotic when you are the one that built it. It begins to become real

Pete

I had meant to include the difference between the design of the original conrod and the thinned version. In Westbury's original the flanks of the conrod were tangential to the crank pin and gudgeon/wrist pin diameters. I have thinned the flanks by 1/64" (0.0156) on each side. I also think the gudgeon/wrist pins are way too big say 5/32" or 4mm may be in better proportion
Original



Thinned



Pete

It looks like it has been over 3 weeks since my last post. I have been a bit distracted but have managed to get a few things done. First the pistons. Basically a simple turning job and I don’t appear to have a photo of that

The plan is to use Viton O rings as this engine is only destined for minimal running and the shelf

I fell into the trap of establishing that I needed 014 rings, going to the store and asking for 5/8” rings and getting 016 rings. I have never really understood why O rings are reference by their ID and not the OD. It is the OD that does the job.

Once the turning was complete the gudgeon/wrist pin was drilled and then the piston set up for the pocket for the little end machined.







Now time for a trial fit and the anticipated clash of the conrod with the cylinder liner was confirmed. I relieved the lower edge the liner. You can just make that out here with the witness make of the end mill just touching the lower face of the casting on cylinder #2

Also the #2 and #3 conrod caps just fouled the inner face of the casting a bit o work with a scraper resolved that problem



That didn’t fix the problem so it was back on to the conrod jig to thin the conrods.



A bit of fettling here and there and the conrods pistons and crank journals were teamed up so an initial full assembly of he moving parts could be attempted.



Without any O rings in place and powered by a battery drill all the moving parts moving in unison. That is all except #3 exhaust valve that is sticking. The valve timing has not been set. This will all come later as undoubtedly the engine will be stripped down a few more times before that is possible.

https://youtu.be/8JD4Gi9MF-A

Pete