ETW Sealion

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Weldsol

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Hi I have not posted this as a blow by blow way of building this engine, just done the photo's to give some idea

Jan, 2020 I decided to go for the sealion but with no castings, so the drawings and ETW's notes from 1959 Model Engineer mag's were purchased from Hemingways and upon arrival started to do a breakdown on CAD to see what metal would need removing from bar stock to achieve each part ready to make a start on machining.

Then the lockdown started so I had to self isolate in my workshop (that is what I told my wife Ha Ha

First was the crankcase I ordered a 6" length of 3 1/2" square, faced the ends and put some datum lines on.
Next was the crank machined from EN16t
Then bearing endplates
Next was the cylinder head
Cam plate
Cam jig
Cam
Rockers (that's another story )
Carb

All the machining was using my lathe or mill.
I will put some more pic's up when I have some more time
Paul
Just remember If it cant be fixed with a hammer it must be an electrical fault
Cam jig.jpgCam3r.jpgcarb 1b.jpgCarb 1r.jpgCarb 2r.jpgCarb 3r.jpgCarb 4r.jpgCarb 5r.jpgcrank end bearing plates r.jpgcrankshaft r.jpg
 
Beautiful work! I am building a Seal Major 30cc. Very similar parts. Getting courage to tackle the camo_O. More pictures please👍
 

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Hi I have not posted this as a blow by blow way of building this engine, just done the photo's to give some idea

Jan, 2020 I decided to go for the sealion but with no castings, so the drawings and ETW's notes from 1959 Model Engineer mag's were purchased from Hemingways and upon arrival started to do a breakdown on CAD to see what metal would need removing from bar stock to achieve each part ready to make a start on machining.

Then the lockdown started so I had to self isolate in my workshop (that is what I told my wife Ha Ha

First was the crankcase I ordered a 6" length of 3 1/2" square, faced the ends and put some datum lines on.
Next was the crank machined from EN16t
Then bearing endplates
Next was the cylinder head
Cam plate
Cam jig
Cam
Rockers (that's another story )
Carb

All the machining was using my lathe or mill.
I will put some more pic's up when I have some more time
Paul
Just remember If it cant be fixed with a hammer it must be an electrical fault
View attachment 126585View attachment 126586View attachment 126587View attachment 126588View attachment 126589View attachment 126590View attachment 126591View attachment 126592View attachment 126593View attachment 126594
 
Hi weldsol,
Very interested in your work, I started making the sealion from castings some 20 years ago and finally finished it about 18 months ago and got it running.
The castings were rubbish but I persevered and managed to finish with modification to overcome the poor quality of the castings.
Recently I've been thinking I'd like build another from bar stock so would be very interested in any info you can give.
Thanks so far.
Where are located?
Graham
 
Hi weldsol,
Very interested in your work, I started making the sealion from castings some 20 years ago and finally finished it about 18 months ago and got it running.
The castings were rubbish but I persevered and managed to finish with modification to overcome the poor quality of the castings.
Recently I've been thinking I'd like build another from bar stock so would be very interested in any info you can give.
Thanks so far.
Where are located?
Graham
Hi Graham I'm in Hertfordshire UK
 
You've just reminded me that I've a Triple Expansion to finish :-(
 
Hi John did you see the other posts ETW2 &ETW3 I did them like that as I could only put up 10 pics at a time on reflection I suppose I could have added to this post as replies and kept as one post ?

Paul
 
Here are a few more pics.
The cam follower one shows a problem I had with the one as on the drawing.
the cam contact was hitting the follower just (and I mean just) above the pad which I considered to be a problem so a fresh set was made with the pad going right up to the boss.
The other issue I had was because I was following ETW's notes and drawings and using BA threads, this was fine until I made the conrods which you drill and tap 5BA and fix the cap prior to machining the big end, I had used 5BA bolts during the machining op's.
Then I tried to source the 5BA socket head cap screws.
Everybody that listed them couldn't supply them then you find out the last known place that had them was in Australia and that was back in 1987 but I went to there site and guess what you got it "unable to supply this item"
So now I was stuck I couldn't go to 3mm cap heads 4BA was to big as the thread would just cut through to the big end.
So I did some checking on BA cap head dimensions and came up with the following :-

The head size on 4BA is only a few thou bigger
The Allen key size is the same
You cannot turn down a 4BA & re-thread 5BA as the core diameter on a 4BA is just bigger than a 5BA so you are left with some 4BA threads .

The solution I used was to get some 1 1/2" long 4BA cap head bolts which gave me approx, 3/4" plain shank to turn down to 5BA o.d. and then thread them

Paul
 

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Hi Paul,
Nice work. How did you profile the outer block shape?
You are obviously trying to replicate ETW build. I was thinking of doing away with the gear drive to the cam and using belt and pulleys. I also had real problems with the original distributor so triggered the ignition from 2 magnets on the crank pulley to hall switch.
Graham
 
Hi Graham
The out profile I had to mark out where the ribs were and the mounting lugs.
then mark out the profile on one end then it was onto the mill with a rotary table and tailstock and then roughed it all down with a 1/4" ripper endmill then for the last 20 so thou used a 3 flute endmill to finish then blend with a fine file.
Mine is not a true ETW build as I have changed a few things mainly on the top end such as pressure oil feed to the cam bearings and change the top cover, also changed his exhaust / inlet manifold.
I will be using gear drive for the cam and oil & water pump, for the ignition will probably go hall effect sensor inside distributor cap.

You never said where you were ?
Paul
 
Hi Graham
The out profile I had to mark out where the ribs were and the mounting lugs.
then mark out the profile on one end then it was onto the mill with a rotary table and tailstock and then roughed it all down with a 1/4" ripper endmill then for the last 20 so thou used a 3 flute endmill to finish then blend with a fine file.
Mine is not a true ETW build as I have changed a few things mainly on the top end such as pressure oil feed to the cam bearings and change the top cover, also changed his exhaust / inlet manifold.
I will be using gear drive for the cam and oil & water pump, for the ignition will probably go hall effect sensor inside distributor cap.

You never said where you were ?
Paul
 
Hi Paul,
I'm in Kent, personally I would think very carefully about putting the hall device in the distributor, they hate emf. And I speak from experience. That's why I timed the spark from the crank.
Others might disagree.
Anyway fine progress can't wait to see it running.
Graham
 
Many production cars use crank mounted sensors, because there is no drive to affect the accuracy of timing. With electronic ignition, the advance timing is done electronically, the can give up to 5 degrees more advance than points and mechanical advance mechanisms. The electronics can also use piezo sensors (like microphones) to sense and retard the engine should any knock occur (e.g. For poorer fuels than manufacturers specify. You hope the garage is giving you the octane on the label, but can never be sure without testing.).
But modern cars use individual plug mounted coils, so individual cylinders can have slightly different timing as throttle and load conditions vary, and should a cylinder be knocking for any strange reason. Electronic triggering of multiple coils is now cheaper than distributors, but plug mounted coils are unlikely to appear on models for reasons of authenticity, and size.
K2
 
Many production cars use crank mounted sensors, because there is no drive to affect the accuracy of timing. With electronic ignition, the advance timing is done electronically, the can give up to 5 degrees more advance than points and mechanical advance mechanisms. The electronics can also use piezo sensors (like microphones) to sense and retard the engine should any knock occur (e.g. For poorer fuels than manufacturers specify. You hope the garage is giving you the octane on the label, but can never be sure without testing.).
But modern cars use individual plug mounted coils, so individual cylinders can have slightly different timing as throttle and load conditions vary, and should a cylinder be knocking for any strange reason. Electronic triggering of multiple coils is now cheaper than distributors, but plug mounted coils are unlikely to appear on models for reasons of authenticity, and size.
K2
 
Re the ignition side I may go to these people or even try ETW's points & coil as this engine will never be driving anything
https://minimagneto.co.uk/Home.phpI'm not sure what way to go yet as it will be a fair bit of time before I have to make that decision

Paul
 
Hi Paul,
I tried standard points and coil ( and I believe many of these engines have worked fine) but I had lots of problems stopping arcing inside the dizzy cap so tried all sorts of fixes even 2 x twin Honda coils using "lost spark" finally getting it running with 2 x magnets on the crank to a Hall device to a CDi.
Also tried buzz box with no joy.
Thanks again for the pics.
Graham
 
Paul,

Great work, I have the Sealion on my "to build" list; I consider it the most refined ETW's designs. I am now building his Wallaby borrowing many of the construction methods from the Sealion--such as main ball bearings in bearing holders and the arrangement of the timing case.

Have you decided how you are going to fabricate the main center bearing? Will you use ETW's design of 7/8" leaded bronze rod? I am still noodling on this one.

Good luck, I will be closely watching your progress.
 

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