ptwizz Posted October 21, 2016 Author Share Posted October 21, 2016 Still not much to see. Here is the beginnings of a rocker. You can see how little is left from the 3" diameter billet. At the risk of repeating myself, I'd like to tell the story of the duck carving man: I was at a local village fete some years ago, where there was a stall selling assorted carved wooden ducks. Behind the stall sat a man on a stool, beside him a pile of logs, each about a foot to 18" long and maybe 4" diameter. As I watched, he picked up a log and began carving it with a small knife. After about 20 minutes, he had produced another duck, which was waxed and added to the display on the stall. As he picked up another log, I asked him "Do you have a design in mind when you start, or just make it up as you go along?" He replied "I just pick up a log and cut off all the bits that don't look like a duck". Since that day, I have described my approach to machined parts in the same way. Pick up a billet of Aluminium 2014A-T6 and cut off all the bits that don't look like a rocker. I have been telling this story for years. Recently I overheard someone who I have never met telling the story to another. Quote Link to comment Share on other sites More sharing options...
ptwizz Posted October 25, 2016 Author Share Posted October 25, 2016 Now looking more like a rocker. I am carrying out each machining operation on all 14 rockers, so I won't know if any of them are any good until I've finished all of them. 1 Quote Link to comment Share on other sites More sharing options...
admin (Simon W) Posted October 25, 2016 Share Posted October 25, 2016 Bonkers amounts of patience! SW Quote Link to comment Share on other sites More sharing options...
ptwizz Posted October 26, 2016 Author Share Posted October 26, 2016 If I were a patient man, I wouldn't have bought the Russian cylinder heads in the first place. As the project progresses, I am leaning more towards the idea of making my own heads. I'll probably get it running with these heads first. Quote Link to comment Share on other sites More sharing options...
Dariuszk24 Posted October 26, 2016 Share Posted October 26, 2016 Thats yout own CNC machine?? Quote Link to comment Share on other sites More sharing options...
cas_whitmore Posted October 26, 2016 Share Posted October 26, 2016 Careful ' you can be shot for mentioning those letters ? Cas. Quote Link to comment Share on other sites More sharing options...
kiwi k Posted October 26, 2016 Share Posted October 26, 2016 2 hours ago, Dariuszk24 said: Thats yout own CNC machine?? i think you'll find Pete will say "Made entirely on my Chinese milling machine" with help of a rotary table and thats it no fancy Machinery Quote Link to comment Share on other sites More sharing options...
ptwizz Posted October 26, 2016 Author Share Posted October 26, 2016 Darius, it's not CNC. It's a manual milling machine with a manual rotary table. I have fitted a set of digital readouts to the three primary axes of the machine, but these are simply an easier-to-use version of the dials on the handwheels. For complex parts like the rockers, my drawings have several sheets. The first one or two sheets simply define the part and tolerances. Other sheets show the angles to set the part for particular operations, the linear distance to move the cutter at that angle, etc. When I design parts, I have to think of how I will make them, how I will hold the part to the machine at each stage, how I will cut a particular face with the tools I have in my workshop, etc. It makes sense to record all this information at the same time as I record the design of the part itself. Quote Link to comment Share on other sites More sharing options...
ptwizz Posted March 28, 2017 Author Share Posted March 28, 2017 I now have a complete set of rockers, each fitted with bronze bushes and a roller tip running on a hardened pin. The cylinder heads require more modification to provide clearance to the new rockers. I had measured one head, made all the rockers and then found that the heads are all slightly different and the one I had measured was the only one which the rockers would fit. As a result, I've had to make another substantial fixture to support each head on it's side so I can machine them all to match. Unfortunately, I still can't post pictures, despite clearing all cookies, history etc. Quote Link to comment Share on other sites More sharing options...
cas_whitmore Posted March 28, 2017 Share Posted March 28, 2017 You need to sort this pic post problem out , interesting to see how you've held parts for milling . cas . Quote Link to comment Share on other sites More sharing options...
kiwi k Posted March 29, 2017 Share Posted March 29, 2017 Funny thing you posting up Pete as Geoff round the corner asked me Monday how your engine was progressing, him being an ex engine designer * is very interested to see it finished. * he designed the Hesketh V twin motorcycle engine. Quote Link to comment Share on other sites More sharing options...
ptwizz Posted May 9, 2017 Author Share Posted May 9, 2017 A little more progress.. The engine now has all it's rockers and pushrods assembled, so I can turn the crankshaft and all the valves open and close at the appropriate times. That's the valve timing phase of the project complete. I've just ordered some more large lumps of metal, most of which will end up in the bucket under my lathe. The first will be the 'seal plate' which closes the oil space at the front of the engine and houses the supercharger drive gears. The second will be the supercharger planet gear carrier, which also functions as the nut which pulls up against all the bearings and spacers on the timing end of the crankshaft. I still can't post photos here. Kiwi - I see Geoff about once a week. I believe he also designed, or had a hand in, the BRM H-16. Quote Link to comment Share on other sites More sharing options...
cas_whitmore Posted May 10, 2017 Share Posted May 10, 2017 They were talking about the BRM on the radio other day. John surtees Bloke called harry and think they mentioned Geoff come up with idea . As you do . Cas . Quote Link to comment Share on other sites More sharing options...
kiwi k Posted May 15, 2017 Share Posted May 15, 2017 On 5/9/2017 at 16:32, ptwizz said: Kiwi - I see Geoff about once a week. I believe he also designed, or had a hand in, the BRM H-16. Yes your right Pete but after that he also designed the V12 which was more powerful and had more success Quote Link to comment Share on other sites More sharing options...
ptwizz Posted September 8, 2017 Author Share Posted September 8, 2017 I still don't have the facility to post pictures. If anyone is still following the slow progress of this project, there is a complete photo record of the build here https://groups.yahoo.com/neo/groups/R_and_R_engines/photos/albums/1849802645 Much time has recently been devoted to getting my microlight up to date with servicing etc, installing a new bathroom and a string of issues with my wife's bike. Winter should see more progress, provided I don't dragged too far into redecorating. Quote Link to comment Share on other sites More sharing options...
alan_k Posted September 8, 2017 Share Posted September 8, 2017 Didn't know they had bathrooms in microlight now I'm definitely following your progress Pete, I want to see this running in the future Quote Link to comment Share on other sites More sharing options...
ptwizz Posted September 15, 2017 Author Share Posted September 15, 2017 The word 'bathroom' may be a misleading description of a hole in the cockpit floor. Any jokes based on the word 'cockpit' in this context will be treated with appropriate contempt. Quote Link to comment Share on other sites More sharing options...
admin (Simon W) Posted September 15, 2017 Share Posted September 15, 2017 I would like to think that you will still ride whatever it ends up in to one of our events when it's all up and running mate SW Quote Link to comment Share on other sites More sharing options...
ptwizz Posted December 21, 2017 Author Share Posted December 21, 2017 Simon, You can be assured that whatever this engine ends up in, it will be shown off to anyone who has expressed the slightest passing interest. End of year progress report: I have now made the supercharger drive gear arrangement and its housing. The supercharger is driven through a planetary gear when 'engaged' and driven at low speed through a roller clutch when not engaged. The planetary gear has a floating ring gear, so that when a brake band is tightened the ring gear is stopped and the blower is driven at 4 X crankshaft speed. I have a few fiddly bits to do for the brake band actuation, then on to the supercharger impeller. The impeller looks exactly like a turbo impeller, but it's 5" diameter! Rather than try to machine it from a single billet, I will be fabricating it from a machined 'cone' and separate vanes. Each vane will have tabs which pass through slots in the cone, to be peened over and finally brazed in place. The impeller will run at 14,000 rpm max. At work, I have access to a 7.5kw pump test rig which I can use to spin it up and check for vibration, distortion and pressure / flow rates. Still have no facility to post photos. I only have the 'Insert other media' button available. 1 Quote Link to comment Share on other sites More sharing options...
ptwizz Posted December 29, 2017 Author Share Posted December 29, 2017 I've created an album, titled 'Off topic - radial engine build'. Here I have posted some more photos showing machine setups for the rockers, finished and fitted rockers and the supercharger gear housing. I'll post more soon. Quote Link to comment Share on other sites More sharing options...
admin (Simon W) Posted December 29, 2017 Share Posted December 29, 2017 SW Quote Link to comment Share on other sites More sharing options...
ptwizz Posted December 29, 2017 Author Share Posted December 29, 2017 Cheers Simon. More photos added: A large bearing is fitted to the cam front plate, concentric with its bearing on the crankshaft nose. This large bearing supports a ring gear which runs free except when the supercharger (S/C) is engaged. A nut screws onto the nose of the crankshaft and locks the bearing inner races and cam drive gear in place. This nut also carried the planet gears for the S/C drive, each of which runs on a needle roller bearing. A brake band will be mounted to the S/C gear housing. A cable will pull the brake band tight around the ring gear, holding it still so the S/C impeller is driven at 4x crankshaft speed. The arrangement is similar to that used in Model T Ford and automatic transmissions. 1 Quote Link to comment Share on other sites More sharing options...
ptwizz Posted May 30, 2018 Author Share Posted May 30, 2018 (edited) A few more photos added to the album. The supercharger (it'd be rude not to) impeller is fabricated around a cone, turned using my home made radius turning attachment. Nine of each of two sizes of impeller vane are cut from 2mm steel, with tabs which fit into the slots on the cone. Each vane is TIG welded at the back of the cone where the tab goes through, then the whole assembly is brazed, using the TIG torch at lower current to accurately heat and draw the Sifbronze material along the join (mostly) without forming blobs and puddles. The assembly is finally trued in the lathe. PS I have now passed GST for the microlight, so look out for G-BZNP at an airfield near you (provided its not too far from me). Edited May 30, 2018 by ptwizz 1 Quote Link to comment Share on other sites More sharing options...
AndyB Posted May 31, 2018 Share Posted May 31, 2018 Absolutely brilliant. I've got a large model plane that you could test it on when finished! A half scale Giles 202 aerobatic model, up for sale this weekend. Quote Link to comment Share on other sites More sharing options...
alan_k Posted June 5, 2018 Share Posted June 5, 2018 Well done Pete on the GST, plus of course your continued work on the radial engine. Quote Link to comment Share on other sites More sharing options...
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