Edwards Radial 5 Build

[petertha]

... to purchase some nitro methane and suitable synthetic oil and an electric starter. I have already sourced some methanol. Recommended percentage of nitro methane in methanol is 3% to 5%..

Beautiful work. You likely already know about all this but just in case... 'grades' of both methanol & nitro-methane very important for successful starting & running of glow engines. When its off-spec, it can make for very frustrating experience. I've even experienced this with good commercial RC fuel gone bad over time because the recipe is quite hydroscopic. What complicates matters is subjective labelling: industrial grade, fuel grade, premium garde.. So try & delve into what you are buying if its off the shelf. You can google some of the RC fuel manufacturers because they typically cite their ingredient specs as example below. Ifthey could get away with lower purity, then they would... but they can't & therefor don't

http://www.odonnellracing.com/about/

I know the Edwards is primarily 'methanol' fuel because the oil pump takes care of lube as opposed methanol/oil premix RC fuel. But another issue to think about is compatibility of the small% oil in your methanol with your choice of circulating oil (if I understand your plan).

IMO a safer solution, maybe just until the engine is running & dialed in, is to buy a gallon of RC fuel. Its available in 0% - 40% nitro-methane & yes will have some typically synthetic and/or castor oil. But if you do the volumetrics & add methanol to this, you will arrive at the target specs. This gives you a bit of latitude if you want to tweak the nitro content which helps with starting & idling particularly. If you can find a supplier of 'FAI' fuel, that has no nitro in it, but takes care of the quality issue. There may well be a cost add, but you'd be surprised. We used to do homebrew mixing & basically threw in the towel because the cost differential just didn't make sense anymore (and nothwithstanding storage danger etc).

 

[petertha]

Not sure how close Bruce is to you, but at least on the same side of the planet. He knows all about F3D racing which consumes 'FAI' fuel (no nitro) & other racing classes at typically 15% nitro. He could likely direct you to some suppliers close to you. Hopefully there is a solution in there for you.

http://bigbruceracing-public.sharepoint.com/

 

[Brian-in-Oz]

Hi Petertha,

Thank's for the fuel info. I had a look at the O'Donnell Racing site and we have a business running an almost identical model in Adelaide only an hours drive away. They are a specialist motor sport supplier and also have a hobby section dedicated to model fuel and oils and claim their methanol is extremely pure and so fresh it is never more than a few days old as they are almost next door to the manufacturer. They have nitro methane available in 1 litre lots and are also a distributor for Coolpower oils. I was aware of Big Bruce Racing who appears to have a nice little niche for those who "have a need for speed". I have one of his models on my flight simulator and it requires lightning fast reflexes just to keep it in sight and from being imbedded in the ground. Good training though!
Future developments will be posted.

Cheers Brian

 

[Brian-in-Oz]

Hi all radial enthusiasts,
Finally the Edwards is firmly bolted to his very own folding, portable test running bench. All that is required now is to fuel and oil up and get a starter motor, cross the fingers and see if I can get him to run. I have a very busy schedule this week but this should all happen if not this week certainly next. I have posted some photo's of the set up and next post will report as to whether a successful run has been achieved or otherwise.

Cheers all - Brian scratch.gif

 

[petertha]

Looks great. Best of luck & keep us posted.
ps - when I first saw that gloss finish on your test bench, I assume the was the 'castor oil mist' finishing system from some extended bench running already

 

[xjs]

Wow. I've slept on less comfortable benches than that. What a beauty. And the motor is a jewel. I trust the Australian media has been properly alerted that something very special is about to happen in Murray Bridge.

All best, Brian -- and keep your fingers clear.

m

 

[Brian-in-Oz]

Hi Michael and Petertha and all - thanks for the good wishes - they worked

On Friday I purchased an electric starter but the flexible cone would not engage the prop. hub so I had to machine up a spinner (see pics). The thread is left hand so that it is being tightened when starting.
This morning was spent going over the Edwards checking valve clearances and filling the fuel and oil tanks and setting the carby to manufactures recommended positions for needle valve and throttle opening for starting. By now it was lunch time and after a very quick lunch it was back to the Edwards to see if it was going to run.
With the starter engaged on the spinner my head was full of teenage memories trying to get small single cylinder Taipan diesels and Glo-Chief engines to run with more often than not the only result being cut fingers from backfiring propellors.
With emotions running high it was with much trepidation that I pressed the starter button and wonder of wonders the Edwards started immediately and almost scared the sh-t out of me. Gathering my senses I checked that the oil was being pumped to the engine and scavenged from the sump - all OK there so proceeded to run at various RPM settings for about five minutes including just ticking over at idle and nothing but nothing sounds like a radial particularly at low RPM.
By this time some neighbours had come over to check things out and I got side-tracked talking to them and forgot to switch off the glow driver (duh!) and flattened the batteries so could not restart it for them. The batteries are on charge now so should be able to have another run tomorrow.
I will post some pics. of the Edwards running and a movie when I figure out how to do that.

Cheers for now - more to come - Brian woohoo1

 

[Swifty]

Well done Brian, the engine looks very impressive. Isn't it funny, we put in a lot of work and care into building an engine, make sure everything is set up correctly, but are still surprised that it runs I'm looking forward to the video.

Paul.

 

[petertha]

Congrats. That must be a thrill. Well deserved & way to go.
(And what a unique spinner solution!)

 

[Brian-in-Oz]

Thanks for your interest and comments Paul. I see you are well on the way with a Howell V4 and I will be following with interest. It looks great. Once the novelty of playing with the Edwards has worn off (if it ever does) I will be looking for another engine to build and the Howell looks like being on the short list. I wouldn't mind doing a flat four either if I could find some good plans for one.
The Edwards was actually my first engine build and I feel I have learned so much from the experience and now feel much more confident than I did when starting on it. Keep up the good work.

Cheers Brian Thm:

 

[ozzie46]

Oh man! What an accomplishment! Can't wait for the video.

Ron

 

[petertha]

I wouldn't mind doing a flat four either if I could find some good plans for one.

Here is an option. I have some of Jungs plans & they are quite complete, metric, suspect off 3D cad model & appear to have 'it runs' track record.

http://www.cad-jung-shop.de/epages/62479729.sf/en_GB/?ObjectPath=/Shops/62479729/Products/00-Z0004-0

http://www.cad-jung-shop.de/epages/...729/Categories/Baupläne/Bauplane_Modellmotore

 

[Swifty]

Thanks for your interest and comments Paul. I see you are well on the way with a Howell V4 and I will be following with interest. It looks great. Once the novelty of playing with the Edwards has worn off (if it ever does) I will be looking for another engine to build and the Howell looks like being on the short list. I wouldn't mind doing a flat four either if I could find some good plans for one.
The Edwards was actually my first engine build and I feel I have learned so much from the experience and now feel much more confident than I did when starting on it. Keep up the good work.

Cheers Brian Thm:

Brian, you certainly pick a challenge for your first engine, but it was executed with great skill.

The links that Petertha has mentioned are the engines that I have been looking at for the next build.

Paul.

 

[Brian-in-Oz]

Thanks for the link info. and accolades guys.
I have had a look at the Modelltechnik link and some real interesting engines there. I was particularly taken by the 165cc OHC V8 with reduction gear drive to the prop. What a lovely looking low profile design but no mention of what
type of ignition. I guess glow would work and if you want a gas engine with spark ignition sort it out yourself.

Addendum: Had a better look at the parts list and Glow plugs are listed so it is glow plug ignition.

But calm down Brian, you haven't even run the Edwards for ten minutes yet. First things first.

Cheers Brian :shrug:

 

[Stieglitz]

Hi Anthony,
Very interested in your build,top skills and yes more pictures please.
Cheers and Thanks.

 

[Brian-in-Oz]

Hi all radial fans - here is a link to a video of my recently completed Forest Edwards Radial running. This is only the second startup and I am still using oil in the fuel and have not yet played with the slow running carby settings. I won't bother with this fine tuning until run in and no oil in the fuel.

Cheers and enjoy - Brian

https://youtu.be/nvmaAWSJdRI

 

[jimjam66]

Man that sounds sweet! Well worth four years of slog just to hear that, I'll bet!

 

[Swifty]

Very nice Brian, if that bench had wings, it may take off.

Paul.

 

[petertha]

Beautiful radial soundtrack, Brian. Its a keeper. Congrats again!

- assume this is your glow plug drive battery? What did you end up using for cells? Is it on all the time or just for starting?

- any idea how the heads are comparing in terms of relative temperature to one another, or is it still just settling in? I often hear the lower cylinders run a bit richer & cooler all thing equal if there is no diffuser type device.

 

[Brian-in-Oz]

Hi Petertha - I am using a McDaniels glow plug driver which is contained in a compartment in the side of the engine mount you can't see. Two batteries are also in this compartment. One 4.8v pack the same as the one you can see in the video and another smaller capacity 4.8v receiver pack that powers the glow driver. In a RC plane the driver can be powered off of the receiver to switch on when it is most required (i.e. at low RPM) and this could be triggered from the throttle servo or even when landing gear is lowered. In bench running it can be manually switched on or off.
The battery you can see in the video is another 4.8v pack which plugs in (as recommended by McDaniel) and acts in parallel with the onboard glow plug battery just to provide extra battery capacity for starting - it is then un-plugged. Helpful if the engine was reluctant to start I guess. I made up all of the battery packs myself from tagged Sanyo eneloop cells and so far have not had to recharge them.
As regards to cylinder temperature I have noticed that after running the lower ones are a little cooler than the upper ones. Apparently some of Forest Edwards later engines were fitted with a fan diffuser in the inlet manifold (also spark ignition).
It has crossed my mind as to the possibility of trying to add a diffuser some time in the future. Maybe a magnetic coupling - anyhow something to think about.
Thanks again for your interest and input to the project.

Cheers Brian Thm: