Once in a while I wondered whatever happened to the "Bentley BR2" thread. Now I know. That is an astounding amount of work and so many nicely-done parts. Four and a half years seems too short for what is on display. Four and a half lifetimes would be more my speed.
Congratulations on getting to this spot and I'm looking forward to the assembly and running.
Beautiful work, cant wait to see it assembled! And those mini-demo movies are really excellent.
Re the ring making, at ~ 0:20 looks you are cutting them with a thin cutoff wheel. Was that kerf width called out in the plans & kind of factored in the heat set operation where the gap is opened on a pin? Reason I ask is articles I've read on the 'Trimble' method has the rings parted or cleaved (ie. no kerf material loss, but then assuming this, a calculation is provided that specifies the gap setting pin diameter).
Then the tempering operation where you are heating with OA torch while spinning, is that to stress relieve or something to do with preconditioning before the oven?
What kind of temperature & duration did you heat at in your tabletop oven to set the open gap?
Went to YouTube to see a finished model of this engine. Is this also one that the block or case spins? Was wandering how this engine performed in flight. Wouldn't the mass spinning throw a centrifugal force that you could feel or cause problems with flight?
Hi Petertha and thanks for your words, I read like 10 times the Tribmle method, very difficult for me to understand all the numbers and calculations,(I´m a doctdor!) so, I had the opportunity to visit my friend Roy Sholl (S/S Machine & Engineering LLC) workshop, he is an expert, and he made the calculations for me, we machined a few in his place, and he calculated the gap pin diameter for me, I did the tempering operation in the lathe with the OA for testing, some days later I got the little furnace, and took them to 1200 F for 20 minutes, then to 900 F for 10 more minutes before cool down, I had an extra .010 in. in diameter, so, after tempering and putting them in the Roy´s device, took them to the grinder until they where just on the money, put them in the cylinder without the piston and put a strong light to see if there where any gaps, did not find any so, good to go (sorry for my english) ant the gap kept in .002-.003 in. after the "touch up" with the emery paper. and to Naiveambition, Lee Hogdson once told me that in fact the centrifugal force was the reason to abandon this engine, because the pilots when steering to the other side, had a great difficult to evade the enemy planes. Lee and Roy have been of tremendous help for me, I did the Ageless 9 cylinder radial before this one, after beeing in my first time at a NAMES show in Toledo, and step by in Lee´s booth, and after i showed him some pics of a Stirling engine (my firs Stirling) that I made, he told me "She (my wife was sith me) thinks you can´t do this, but I know you can, I will help you, just e-mail me when you need it", I am sure he regret sayin that, I wrote many many mails, and he was always very kind and tolerant, I decided to take some pictures and tape some video, here is the link in case you want to see it
This is a tons of hours of work. Impressive job.
For being a Doctor you have great machining skills. Did you have some experince with machining/engineering before being a Doctor?
Will be following with great interest.
Keep the photos coming
Hi Edi, no, I did not had any experience at all, indeed, I started about at the age of 55 yr. old, went to a Saturday morning machining introductory course (6 weeks) and had 2-3 patients that are actually tool makers in my town, and they allow me to go to their shops (don´t you touch anything!), and bought some tapes, read a lot in machinist magazines, and started making ships and a lot, I mean, a lot of errors, but is so therapeutic for me, really the best hobby in my humble opinion, my colleagues do not believe that I can do this, now they treat me with respect! Ha ha ha!. and to Byawor, hope i could help you, don´t know if you mean the mechanism in the cylinder heads (like the video I posted) or when the valve lifters are installed, not there yet, but today I started with the assemble, will post some pics and videos hope very soon
Again, thanks to all, I feel like a rock star!!
byawor. When I made my Bentley I made the same cams and cam rings as you show. The only problem I has was after running it for a while I sheared the square key that hold the cam rings in place. When that happen it ruined the cams and cam rings. I had to make new ones and replaced the brass key wit ha steel key. The first set of cam gears and rings I made on a manual Bridgeport. The second set I made on a CNC machine. Rich