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- Jan 7, 2016
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Wow. That is incredible. Do you have a build thread somewhere; maybe on another site? Would love to know more but don't want to derail Jeff's thread.
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Edwards Radial 5 build thread --- PHOTOS!
- Thread starter JRaut
- Start date
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- Dec 23, 2019
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- 1,138
First I want to apologise to Jeff I dont want to push in on his thread but I am not sure where to go to answer brino's request. But no i dont have a thread for the traction engine as I am new to all this so just posted a few photo. Thanks for all your kind comments.
- Joined
- Mar 26, 2018
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- 2,719
Well, I for one would greatly enjoy if you made a new thread to share your excellent work!
- Joined
- Mar 9, 2018
- Messages
- 461
Ditto, let's see some photos of that thing.
Hello Gentlemen
Being looking into where to get the materials and parts for the radial engine. Have a question the valve cam gears I have found in the UK but the internal ring gear is either in steel or delrin plastic rather than the brass one shown. I was thinking the steel would be fine would like your ideas on this.
Regards
Myford10
Being looking into where to get the materials and parts for the radial engine. Have a question the valve cam gears I have found in the UK but the internal ring gear is either in steel or delrin plastic rather than the brass one shown. I was thinking the steel would be fine would like your ideas on this.
Regards
Myford10
Hi Myford10.
The Ohrndorf 5-cyl I'm building is similar to the Edwards & it calls for steel ring & steel spur gears.
www.engineman.de
Same for the Jung-5
www.cad-modelltechnik-jung.de
These 2 examples & the Edwards are somewhat similar in that the cam itself is a separate part which is mated to the ring gear. Thus the cam surface can be hardened & not the gear itself. Other model radials have the cam lobes cut directly from the ring gear OD blank and then the whole part is hardened. Therefore steel is likely the only choice. I cant help you on Delrin, it would be the first time I've heard of it. Suspect you might have to delve into how it would be retained. I see more downside than upside overall.
Having said that, I really don't know what the loads are on the planetary gear drive. I've been wondering because my design calls for Loctite on the gear surfaces. I guess their sole purpose is to lift the valve rockers, which cant be a lot compared to more driveline related components.
The Ohrndorf 5-cyl I'm building is similar to the Edwards & it calls for steel ring & steel spur gears.
Bauplan: 5 Zylinder Sternmotor | Martin Ohrndorf Modellbau & Technik
Bauplan des 5 Zylinder Sternmotors von Martin Ohrndorf. Für den Nachbau ist der Bauplan des 9 Zylinder Sternmotors zwingend erforderlich!
www.engineman.de
Same for the Jung-5
Construction plans model engines
www.cad-modelltechnik-jung.de
These 2 examples & the Edwards are somewhat similar in that the cam itself is a separate part which is mated to the ring gear. Thus the cam surface can be hardened & not the gear itself. Other model radials have the cam lobes cut directly from the ring gear OD blank and then the whole part is hardened. Therefore steel is likely the only choice. I cant help you on Delrin, it would be the first time I've heard of it. Suspect you might have to delve into how it would be retained. I see more downside than upside overall.
Having said that, I really don't know what the loads are on the planetary gear drive. I've been wondering because my design calls for Loctite on the gear surfaces. I guess their sole purpose is to lift the valve rockers, which cant be a lot compared to more driveline related components.
- Joined
- Mar 9, 2018
- Messages
- 461
Hey @Myford10, looking forward to someone else building this motor as well. Hopefully I can find some time to get back into the swing of things before you beat me to the punch!
I don't think there's anything special to the ring gear being brass. Seems to me steel would work just fine. I suspect Edwards opted for brass because that's what was available.
If you were really feeling frisky, you could try to cut your own. I've got a set of drawings/construction notes on building a clock that features an internal brass ring gear. The author of the construction notes goes into great depth on building a mini sub-spindle holding a form-tool fly cutter of sorts, driven off a small motor coupled with an o-ring (if recollection serves).
Let me know if you're keen on trying to pull something like that off. I'm sure I can find those notes somewhere in my shop library.
I don't think there's anything special to the ring gear being brass. Seems to me steel would work just fine. I suspect Edwards opted for brass because that's what was available.
If you were really feeling frisky, you could try to cut your own. I've got a set of drawings/construction notes on building a clock that features an internal brass ring gear. The author of the construction notes goes into great depth on building a mini sub-spindle holding a form-tool fly cutter of sorts, driven off a small motor coupled with an o-ring (if recollection serves).
Let me know if you're keen on trying to pull something like that off. I'm sure I can find those notes somewhere in my shop library.
Hello Gentlemen
Thanks for your replies and it is good for the steel gear. ( delrin is a type of plastic). JRaut i have thought of making the gears but could not go though broaching them on the lathe as doing some keyways was bad enough. So had an idea of some power cutter so if you could dig out the cutter you have described would be great. Looking at the price of the brass to make the ring gear is not that far off the price of the steel gear here in England of around $45. PS I dont think I will start before you finish let alone finish it.
Regards
Myford10
Thanks for your replies and it is good for the steel gear. ( delrin is a type of plastic). JRaut i have thought of making the gears but could not go though broaching them on the lathe as doing some keyways was bad enough. So had an idea of some power cutter so if you could dig out the cutter you have described would be great. Looking at the price of the brass to make the ring gear is not that far off the price of the steel gear here in England of around $45. PS I dont think I will start before you finish let alone finish it.
Regards
Myford10
Hi JRaut, how goes the engine build? I'm back working on mine again in between distractions.
I thought you might find this interesting because of your creative mods to adjust your timing. I found this website which is a mutherload of past engine reviews. http://sceptreflight.com/
I was there principally looking to evaluate carb orifice size as a function of displacement (more on that later). But while I was recording numbers I also made note of the timing where it was stated. I focused on O.S. engines (all methanol glow like ours). I could probably go back & harvest sme Saito or others too. Then I added some 'designed' radial radials just for comparison. Here are some screen grabs of my spreadsheet. Among the O.S. engines its a bit of apples & oranges of course. The single cylinders generally have higher rpm, they started to grow bigger valves over time, usually had muffler pressurized fuel tanks etc. Anyways here is the data FWIW. Hope the chart makes sense, if not ask. Its about the only simple way I could think to display.
I thought you might find this interesting because of your creative mods to adjust your timing. I found this website which is a mutherload of past engine reviews. http://sceptreflight.com/
I was there principally looking to evaluate carb orifice size as a function of displacement (more on that later). But while I was recording numbers I also made note of the timing where it was stated. I focused on O.S. engines (all methanol glow like ours). I could probably go back & harvest sme Saito or others too. Then I added some 'designed' radial radials just for comparison. Here are some screen grabs of my spreadsheet. Among the O.S. engines its a bit of apples & oranges of course. The single cylinders generally have higher rpm, they started to grow bigger valves over time, usually had muffler pressurized fuel tanks etc. Anyways here is the data FWIW. Hope the chart makes sense, if not ask. Its about the only simple way I could think to display.
