ETW Sealion

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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.
Hi there
Yes the centre was completed partially when the crankcase was machined ( the bearing cap ) and the bearing was made after the crank was finished and is now installed with the crank.

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
Hi Graham I sent you a private message
Paul
 
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.
Hi there
on re-reading your post here is the description on how I made my centre bearing.
The first thing I did was to make a plug gauge to the diameter of the centre bearing of the crank,
Then another one to fit the OD (between the flanges) of the crankcase and bearing cap.
Next was to mark out the centre of the bronze (leaded) bar then onto the mill and drill and tap & counter bore for two 4mm cap head screws ( the clearance for the screws are opened up after slitting ) Note allow enough material to allow bearing width and screw heads) then slit down the centreline then saw the top half through just passed where the cap heads are. Now clean up the faces and tin with soft solder (not quite up to the threaded holes)

Now you can bolt the two halves together, heat the bar until the solder runs, tightening the cap heads as you heat I also used an old toolmakers clamp on the end just to make sure it was pulling down equal.
Now you can chuck in the lathe, I did the bore first (using the plug gauge) , then roughed out the OD between the flanges, keeping the outer flange a bit thicker as this can be reduced after getting the OD to size using a mike and the gauge for the OD as a reference.
For sizing the width between the flanges I used the bearing cap and a feeler gauge to give me my running clearance. Now face back the front flange to give you the required thickness (distance to outer edges taken from the crank) I put a groove behind the rear flange so that I could measure the total width
Now you can put in the bore the oil groove then part off .
I know this sounds long winded but after doing the bearings for my Shay loco and having the two halves separate during machining I went this route with no further issues

Paul
 
Thanks for your detailed explaination Paul, it makes good sense. The use of solder is interesting, I understand the need to insure the two halves remain secure in the proper orientation while turning the ID and OD of the bearing. I have not made my crankshaft yet, but will keep your method in mind for when I am ready to fabricate my center bearing.
 
Finally found some time to get on with a bit more of the engine.

The oil trough I machined from 1/2" flat plate by bolting uprights each end and setting it on the mill between centres using my rotary table and tailstock and ball nose milling cutter.

The oil and water pumps I carved from round bronze bar using the lathe and mill, the sockets for the gears were done on the lathe using a three jaw chuck held in a four jaw chuck so I could set over for the gear centres.
Note the P.C.D. on the oil pump gears is 1/4" and 5/16" for the water pump gears.

The drive for the pumps is by a skew gear driven by the crank. and the cross shaft is grooved to drive the oil pump

The distributor cap was a pig the setup for drilling due to its shape and the hole centres were pre marked in the injection moulding and were way out for the 90 deg, between each one, so took a bit of head scratching but got there in the end.
I'm going the contact breaker points route for the ignition, I say that but all the points will do is trigger a processer so will only have 10 milliamps across them.
The rocker for the points was made from Peek and brass.
Then the clips for holding the distributor cap. I contacted a clock repairing friend who was able to supply me with some clock spring material and once made soft with a bit of heat were easy to shape then a bit more heat and a quenched.

Paul
 

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Hi Paul
May I ask where you sourced the skew gears, or if you machined them could you touch on that briefly. Im curious as to how I would cut these.
Thanks
John
 
Started to do the final assembly two weeks ago then the calamity happened.

When I finished the block and the liners were installed I lapped the face of the block, I also lapped the face of the cylinder head as I was not going to use a gasket just a smear of Hylomar universal.( this was around 3 - 4 months ago)
I had trial fitted the head to the block when doing the centres for the cam drive gears and drilling the front plate for the cam bearing so I knew everything was in line and the gear mesh was correct.
Then 2 weeks ago I had to move some stuff in the workshop, turned around with a box I was carrying only to clip the cylinder head and knock it off the surface plate onto the bench so maybe a 100mm drop.
When I had got rid of the box I was carrying I picked up the head only to find it had taken a hit on the lapped face.
It didn't look that bad maybe a 1/4" mark and it didn't look very deep more of a scratch BUT it was where it was right across the narrow part where it would have to seal the centre cylinders.
After a lot of very strong words and thinking how to overcome this I decided to re lap the face which I did, then all the knock on effects started to add up as I had taken 3 1/2 thou off to clear the damage so the cam bushed no longer fitted and the gears no longer fitted.
So I decided to do a PTFE gasket I managed to find a local company that produce different thicknesses and spoke to a very nice person and asked if they did 0.1 mm thick sheet or tape, he could not get his head around that it was for a small engine and I only needed a piece 150mm x 50mm but after explaining things to him he ok I will send you a free sample ( which turned out to be 300mm x 300mmm) which was a result.
As soon as it arrived it took me around 1hr to produce and fit the gasket and once fully tightened the head the cam bush slid in and the gears fitted and were back in mesh as if nothing had happened.
So it goes to show that **** happens but it can be cleaned up

Paul
 
Got a bit more done over the last two weeks
All the oil / water /exhaust pipes which were in copper are now wearing a nice coat of Nickel via the vinegar / Nickel/ phone charger, for the Nickel I used the pure Nickel core wires from some cast iron welding rods.
Got the HT leads done apart from plug connectors (waiting on them along with the rest of the electrics including the plugs)
Got sort out making a Radiator / Fuel tank / way of starting, also got to dry run it for a bit just to bed everything in

Paul
 

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Hi Paul, is the electroplating for "a nice coat of Nickel via the vinegar / Nickel/ phone charger" as simple as that? When I tried copper plating, I managed to get a layer of copper that didn't stick to the steel I was trying to plate. - so I painted it instead... Do you simply pickle you parts before plating?
K2
 
Hi Paul, is the electroplating for "a nice coat of Nickel via the vinegar / Nickel/ phone charger" as simple as that? When I tried copper plating, I managed to get a layer of copper that didn't stick to the steel I was trying to plate. - so I painted it instead... Do you simply pickle you parts before plating?
K2
First I'm not a plating Guru I just looked online to find the easiest /low cost way.
All the Nickel plating was on Copper / Brass / Bronze parts these were all pickled in Citric acid ( to remove all flux residues after silver soldering) then prior to plating given a thorough de-greasing.
The vinegar was 20% acidic (used in UK for weed killer ) plus a small amount of salt (one teaspoon to 2.5 ltr vinegar).
the depth of coating was down to how much time / power of phone charger plus you can always keep re dipping the part for a thicker coating.

Paul
 
Thanks Paul. Sounds like my de-greasing wasn't any good. I thought after pickling it was de-greased.... only handled with tongs, but the copper simply wiped-off my stuff with my fingers.
Thanks for the help!
K2
 
Found some more workshop time so got on with the radiator, I looked at the computer radiators but I did not want the inlet / outlets on the same side so sketched out an aluminium rad then worked out how to make it.
the pictures below will give you some idea how it was done.
I TIG welded the top & bottom closing plates though if you don't have welding kit then it could be made using bolted plates.
The side plates I ended up slitting to get a better clamping effect for the fins to the tubes

Paul
 

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I used to use zinc based rods for soldering aluminium, but now I used a fairly new solder that is 95% aluminium. (It is cheap!). Works very well, easy use use with a blow-torch. I have used to make small boxes for ceramic burners using 1mm aluminium sheet. Careful use of the flame avoids melting the whole lot, but I do not have TIG, and this makes very strong assemblies. As a method, it is not like capillary silver soldering or brazing, but much more like stick welding to make fillets of the added material. I have fitted 6mm aluminium tubes into the 1mm ally sheet , so this could make a radiator, if the material is big enough. But if I was making one with 4mm tubes, or smaller, I think I should make a brass assembly using silver soldered tubes into headers. Although they used to be made with lead soldered copper or brass in full size.
So lots of ways available without TIG.
K2
 
That radiator looks great. I am building a Sealion also and have been thinking about a radiator. would you consider sharing the particulars of your design?

Ron
 
I used to use zinc based rods for soldering aluminium, but now I used a fairly new solder that is 95% aluminium. (It is cheap!). Works very well, easy use use with a blow-torch. I have used to make small boxes for ceramic burners using 1mm aluminium sheet. Careful use of the flame avoids melting the whole lot, but I do not have TIG, and this makes very strong assemblies. As a method, it is not like capillary silver soldering or brazing, but much more like stick welding to make fillets of the added material. I have fitted 6mm aluminium tubes into the 1mm ally sheet , so this could make a radiator, if the material is big enough. But if I was making one with 4mm tubes, or smaller, I think I should make a brass assembly using silver soldered tubes into headers. Although they used to be made with lead soldered copper or brass in full size.
So lots of ways available without TIG.
K2
I wanted an aluminium radiator and yes I could have ally gas brazed the whole thing (12% silicon ally brazing rod and flux) but the problem with brazing aluminium especially fillets is you cannot easily remove the flux (corrosive)
The design was done so that no welding or aluminium brazing needed to be used.
I welded the top and bottom plates because one I've got the welding gear and two it would have meant a lot of drilling and tapping but if you have not got the welding gear then the rad could still be made.
all the tubes are sealed by "O" rings (as shown in the pic's ) the tubes are machined from solid bar so I could have the flanged bits for the "O" ring closing the tubes are 6mm dia, with 1mm wall

Paul
 
That radiator looks great. I am building a Sealion also and have been thinking about a radiator. would you consider sharing the particulars of your design?

Ron
Hi Ron yes I can put up some PDF's with no dimensions that will give you some answers
Paul
 

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