New I/C diesel project – ETA15d-x2

[Ramon WilsonParticipant @ramonwilson3]

I really don’t like digital calipers!

Actually I never have done but these were a gift and, it has to be said, they are so much easier on the eyes than conventional ones it’s easy to succomb. Well…… I really don’t like them now ……

 

All the parts are now machined for all three engines – well I thought they were until today.

 

This is the sum total of the parts ready for assembly and they have now all gone together well with very little fettling required – just a small scraping inside the crankcases to allow the big ends to clear where the bore enters the case and a small amount of clearance milled on the S&J backplate to clear the piston at BDC (the S&J backplate has a much deeper register)

 

When I measured the ‘Cox’ carb body and venturi I did so while my friend who’d brought it over waited. I used digi calipers and made a note of all dimensions. The sketches done the engine went off and the parts were drawn out to the dimensions. Once assembled on the S&J however it looked a little out of scale so I asked for another loan. First thing noticed today then was that my version was somewhat thinner than the original

I’d kept the original sketch and dimensions so it did not take long for the penny to drop. Some dimensions were correct but others a consistent 1.38 short. I guess I must have inadvertantly re-zeroed it whilst measuring – something easily done with the pair I have. Deary deary me I said or something rather similar

 

Apart from this small set back – the parts will require making again – I have had an attempt or two at nickel plating the needle valve parts. Though not totally satisfied with them so far they do actually look better ‘in the flesh’ than in the image and far more in keeping than just plain brass. All three parts were made from the same piece of brass but all three exhibited differing qualities of finish. Strangely enough the reduced diameter of the fuel inlet plated with a shiny, bright, almost chrome like finish but the rest was more a dull grey. More work is need here really to get something more satisfactory and consistent but the amount of plating salts is limited for too much experimentation. Whatever this is what the first off looks like after the test assembly – it has to be stripped for anodising so has not been run yet.

 

 

I’m off to Duxford for a day out tomorrow but next week should see them finished and running – more a bit later then.

 

Regards for now – Ramon

 

 

 

[Ramon WilsonParticipant @ramonwilson3]

Hi again.

Well further to the last post I’m glad to say things are now back to square one

 

New parts have been made and they are much more in scale and in keeping to the original.

 

This shows before (on the left) and after (right) and the engine from which the parts were copied.

The other accomplishment has been the nickel plating. I was not happy with the previous parts so re-cut all the hex surfaces and began again. I also cut several more small test pieces from the same bar. Starting with these at perhaps a somewhat more observant pace I found the initial flash of plating was quite shiny and formed rapidly – a matter of seconds in fact.

I had also misled myself by thinking that the plating action should give off a rapid fizzing and began with a current which created such but it quickly became obvious that this was detrimental to the finish. By reducing the current right down until the fizzing was barely perceptible the finish showed a dramatic improvement.

By the time I felt ready to try the parts again I was down to very low current and literally dipping the part in and out of the solution for no more than a couple of seconds.

It still proved slightly inconsistent part to part but the results are far better than the first attempt and give an acceptable overall look installed on the engines. The solution used was bought off ebay – a litre for 9.99 plus postage. There is sufficient nickel in the solution for a small amount of plating without the need for a nickel anode. It appears to have worked well on this basis in this situation so its fair to say I’m well pleased with the outcome – albeit not perfect it proved much simpler than anticipated.

 

This was the first part done – the silicone tube is to prevent the threads from plating – lesson learnt the first time as they became very tight in the intake!

Degreasing is obviously an important factor too. The parts were cleaned in acetone first then washed in water. A 2-3 min dip in 10;1 sulphuric acid followed by another wash then a final 5 min soak in distilled vinegar and salt solution as recommended. Despite this I feel the parts were still not clean enough in areas. On the larger knurled needle valve the area which must have had some flux residue from soft soldering the needle in

simply would not plate at first until it had really been abraded using a small piece of Garryflex abrasive block. Even now there is a change of colour that whilst acceptable can still be seen.

 

All the parts finished including the ‘backadised’ parts. This was done using Koldblak – nothing very special to that – it’s very easy to do but what is surprising is that the Koldblack was bought in from my works in 1985 and this was done in the small tub of solution mixed originally all that time ago. Some shelf life eh It’s so long ago I have forgotten the ration of neat Koldblak to water – 5 to 1 seems to ring a bell – does anyone know the correct ratio?

Well if all goes well the anodising should be done next week then it’s time for a run up

As usual – hope this is still of interest

Regards – Ramon

 

 

[MikeParticipant @mike89748]

Hi Ramon,

I hope you don’t mind your excellent and informative thread being disrupted by an old codger’s reminiscences, but it has brought back to me memories of a time in the 70s when a pal and I ran a pair of ETA Elites in control line team race events. Like you on one of your engines, we made Cox-type carbs (in the local tech school workshops) – couldn’t see the point in reducing the flow through the venturi with the spray bar. As I recall it was quite successful once we hit on the right diameter and tapers, although we never did get as far as copying the Cox drum valve.

Another thing we did was to fit aluminium bronze contra pistons, with the thought they would aid heat dissipation. The al-bronze was valve guide material scrounged from the old BRM Formula 1 workshops at Bourne, Lincs. – a fascinating place to visit.

I can also remember seemingly endless fuel brewing experiments to get 34 laps at max power out of the allowed 7cc of fuel. Best anaesthetic-grade ether rather than solvent, and I also remember writing to all the leading paraffin manufacturers to ask them the calorific value of their fuel. I think the engines ran best on Aladdin Pink! We also tried many different oils in addition to the usual Castrol R, and I seem to remember a lubricant developed by Valvoline for outboard hydroplane racing allowed us to considerably reduce the oil content of our fuel.

We were the champions of our own club for a couple of years, but never got further than the quarter-finals in the Nationals.

Ramon, many thanks. You have brought back some very happy memories!

[Ramon WilsonParticipant @ramonwilson3]

Hi Mike, No I don’t mind at all, in fact it would be pleasing to hear a few more

 

Although a life long control line flyer I only had a short foray into team racing in the early/mid nineties via trying to encourage some youngsters to get involved with ‘Mini Goodyear’. That died an early death due to lack of interest after the initial buzz – that’s the kids lack of interest, not us.

 

My interest in TR though was from the outset but for some reason this corner of Suffolk never seemed to produce any like minded competively interested parties so it remained for years very much a ‘magazine led’ interest.

Mini Goodyear did however take a hold and my wife became my pilot for about three years. We never did particularly well mainly due to not having powerful enough motors – at the time all plain bearing – and never anything that would consistently re- start ‘first flick’ but we did enjoy ourselves tremendously. It was this event that began my interest in trying to improve the performance of the stock engines – mainly MVVS 1.5’s and PAW’s which although never really successful did lead to making various bits and pieces – a forerunner of current interest. Ipswich ‘boys’ Green and Long’ had something truly unbeatable but we never ever came close.

 

I also built a (my third over the years) Contest Kits Voodoo for an Oliver Tigre for vintage TR but this one proved a poor model in flight – undulating and difficult to keep in a groove. This period coincided with a deep (and my main) interest in C/L aerobatics along with some extreme pressures at work so I took a complete break for a year or so returning later to concentrate solely on the latter. I sold all my TR stuff off at the Nats swapmeet about eight or nine years ago.

 

Fortunately (?) there is little control line flown in this area now which I have to admit would be a big distraction if it were. It would not take much to respond to an ever present itch

 

Nice to hear your reminiscences on fuels, as you can imagine we dabbled a bit with that

too but the Ali- bronze CP is new. You’d have a job getting Aladin Pink these days though!

 

Thanks for your thoughts

 

Regards – Ramon

 

 

 

Edited By Ramon Wilson on 26/06/2011 23:52:36

[Ramon WilsonParticipant @ramonwilson3]

Well Guy’s journeys end fast approaches……

 

I’ve had a really good session in the workshop today anodising all the requisite parts and the engines are now finally complete. There remains but one thing and that is to run them. I was about to do this this afternoon as the last part was done but my neighbour decided to have a Bar-B so I felt it was not exacly an opportune moment – ”Maybe tomorrow Jack”

 

The anodising itself went well but the dyeing could have been a little better. I used ‘Waterman’ ink – ‘South Sea Blue’ – for the blue which took well – too well actually it had to be diluted considerably to get the light blue I was after and even then it’s a little brighter than I would have liked. When sealing it over boiling water I left it static and some of the colour leached out on the side nearest the water. Ready for this on the Mk 2 with a deeper blue I continually turned this which proved much better. However so keen to see what it would look like on the engine I sprayed WD40 over it too quickly and this leached out some colour too. The test pieces I had done were not sealed but left on the bench. I tried these to see if the WD would affect them but it was fine – lesson learnt there then – after sealing I shall let it stand for a good while.

 

So finally after this very pleasurable journey here they are

 

This is the Mk1. The colours are as the original the blue a little brighter perhaps but it did vary from engine to engine

 

The Mk 2 had a sturdier and longer front housing along with a beefed up crankshaft. It also had an extra fin cut in the head. The prop drivers were not anodised but the compression screws were blacked. I decided not to on this one.

 

This is the Stocton and Jehlik version. Herb Stockton and Don Jehlik were an American team race pair that were very successful with their ‘version’ of the Eta 15. Apparently the only Eta parts were the liner and piston, crankcase and shaft. The August 1967 Aeromodeller featured drawings for the modified parts and these are what were used to recreate this as a 5cc. The original rotor disc intake was replaced by a steel drum running in an ali housing driven (as per a rotor) by the crankpin. As previously mentioned it utilised the front housing and venturi system from a Cox 049 glow engine.

Nothing matched the scaled up version so the housing was machined from hard plastic. The ‘gold’ anodising is just yellow dye.

You know, it’s strange but now they’ve been anodised I think I preferred them in ‘all ali’.

Well that’s it folks – I’ll let you know how they run tomorrow.

Regards for now – Ramon

Edited By Ramon Wilson on 27/06/2011 23:38:33

[Bill PudneyParticipant @billpudney37759]

Beautiful Ramon, just beautiful.

Can’t wait to hear how they run.

I’ve thoroughly enjoyed your story, and the Racer one before it.

Once again beautiful work!!

best regards

Bill Pudney

[adyParticipant @ady]

Amazing to watch, and fascinating.

Thanks for sharing.

[Ramon WilsonParticipant @ramonwilson3]

Well that’s it then folks, journeys end

 

Mk 1

 

Set each one up this morning and pleased to tell they all started well once the compression setting was established and all appear quite powerful. They swung a 12 x 5 wooden prop with ease. No rpm check was done as obviously they need to bed in first and I had to think of the neighbours. They certainly have a lovely ‘bark’ and to hear and see them run after the build period is a real bonus.

 

Mk2

 

They were purposefully kept rich for this first run hence all the exhaust and whilst they were not run for long there was no evidence of excessive black exhaust gunge. Compression seals with the CI piston and En1a liners are better than anticipated – remains to be seen how long that will last though these engines will never have more than the occasional run.

 

S&J Version

 

Just remains to say thanks for your kind words, Bill and Ady, and thank those who have responded over these last few months either by post or PM. It’s been difficult to assess whether it’s what is wanted by the majority but as you obviously keep looking I could only assume it was. Hope I haven’t gone on too much

 

 

Now, I’m respectfully(?) reminded by my tolerant and ever patient better half that perhaps it’s time to catch up on those domestic issues that have been somewhat neglected over recent weeks so it’s time for a break for a short while before tackling the next one.

 

Regards to you all – Ramon

Edited By Ramon Wilson on 28/06/2011 14:17:05

[MikeParticipant @mike89748]

Only one way to describe the whole project, and the way it was narrated – absolutely brilliant!

Incidentally, just finished reading Matt Oxley’s book “Stealing Speed” – a must for anyone interested in two-stroke design and tuning. Highly recommended.

[Bill StarlingParticipant @billstarling10428]

Dear Ramon,

If any one had asked whether I was interested in small I/C engines I would have said ‘No’. However I’ve been fascinated by your series. Superb workmanship, excellently described and illustrated. It’s been an eye opener. Thanks very much. I’m looking forward to the next one.

Best wishes,

Bill.

[WindyParticipant @windy30762]

Thanks Ramon a very informative series.

 

As an old ex motorcycle competition rider I have just ordered Matt Oxley’s book “Stealing Speed.

 

I would like to see some articles on building and tuning model home built engines for maximum performance.

 

Any offers.

 

Windy

[Ramon WilsonParticipant @ramonwilson3]

Hi Windy,

I would have thought you don’t have to look far for that within your own hydro group – from what I have seen the accomplishments there are impressive indeed to put it mildly. I was in awe at the examples of the motors on the stand at Ally Pally.

 

My own attempts (at tuning) have been based on others knowledge, both written and first hand, but found it a bit hit and miss – and very much easier to miss than hit and bugger up the reasonable performance that you began with but when it does work ……….well

 

I may be wrong here but outside of some basic principles I feel it’s also ‘event specific’ – what may be okay for one kind of use may not do for another. I must admit though that building the S&J engine has harboured thoughts of an own design 5cc incorporating features to enhance performance but it’s a way off yet.

 

Regards – Ramon

 

 

 

 

 

 

 

 

 

Edited By Ramon Wilson on 28/06/2011 23:34:42

[SpurryParticipant @spurry]

Hi Ramon

 

A wonderful project. I’ve really enjoyed all the posts and explanations. Thanks.

 

I have to make a prop driver, so will try your little dodge with the knurling tool at 90°.

 

Keep up the good work

 

Pete

[John McAvoy 1Participant @johnmcavoy1]

Hello, I know this is a really old post, but I am wondering if plans are available for the ETA 15D?

thanks, John

[Old SchoolParticipant @oldschool]

John I believe that the original ETA drawings are on the internet somewhere an ask on the Barton club website might help with location.

[JasonBModerator @jasonb]

Ramon's 5cc drawings can be found in this build series

[Steve Talbot 1Participant @stevetalbot1]

Hi Jason your link only seems to go to part one. Unable to find any continuation sites

[Roger ClarkParticipant @rogerclark]

Look about halfway down the page, links to all 13 parts Steve.

Roger

[JasonBModerator @jasonb]

Or just change the URL from ……………..engine_1 to ………..engine_2 etc

[Author]

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