Member postings for geoff walker 1

The first one I ever went to was at the Seymour Hall in the early 1970s, just a lad in those days.

YeS, I remember the Seymour hall, first M.E.E. I went to around 1974/5.

It was a little cramped, everything seemed to be squeezed in.

It was much better when the exhibition moved to Wembley a few years later

I remember the Seymour hall had a good sized adjacent swimming pool which looked very inviting. No towel and bathers so couldn't have a dip!!!!

Geoff

Hi All and Chris, thanks for your post,

Well all assembled and ready I believe for a test run.

The engine is made much the same as the original design. I split the crankcase in two and modified the prop shaft to accept a commercial prop driver but other than that made to Ron's drawings and Chris Bolls design..

The compression feels good and all seems as it should be? (hopefully).

Will be travelling to Chester soon to see my mate who is an aero modeller. If this engine will start he will get it going!

So fingers crossed and if all's well a video to come.

Ramon you asked if I had plenty of fuel to run the engine. The answer is no but as you may have gathered I know a man who has!!

atb Geoff

Hi Gareth,

I see you have added your reversing switch.

I added mine some years ago and have had no issues.

I had to reverse the rotation to suit a gear milling fixture I have.

Good luck with the tapping but as J said do take care

Geoff

Hi Thanks again Gents,

More progress reports in due course.

I need to make another fixture to hold the piston while lapping into the cylinder, like this one I used on the firefly.

Cheers for now

Geoff

Hi Keith,

Thanks for the reply.

I think it's unlikely to go airborne, maybe, ...but unlikely.

So I'll leave it as it is for now

Thanks Geoff

I bought this rotary table about 4 years ago. I had to tweak it a little before the first use but since then it's had lots of use and I've been really pleased with it. I added a circular alloy table to make it easier to mount chucks and other attachments. The chuck in the picture is an Indian Zither, bought from ARC, again about 4 years. 4 jaw self centring, very accurate and for the price I paid good value.

Both seen here in use milling the transfer channels and drilling the port holes in the Boll Aero cylinder. The cylinder is made from EN1A mild steel.

Progress has been ok, here is another picture of some completed parts.

The cylinder head screw for adjusting the contra piston is made to the sizes in Ron's drawings. I have seen some engines like this one which have a locking lever on the head presumably to secure the position of the screw and the optimum compression position for the contra piston. My feeling is that the lever is a good addition as when the engine is running (if the engine runs!!!!) there may be a possibility that the screw may vibrate loose and lose the setting? Any thoughts.

Geoff

When I made the "firefly" some years ago I used EN8M for the crankshaft and the cylinder liner.

I assume that the same will be ok for this engine but of course I am open as always to advice.

I will need to place an order soon from M metals.

Geoff

Some more progress today.

After some initial milling, shaping and drilling, set up the con rod on the Sherline.

Perfect for the smaller items.

Last photo shows it alongside the head, finished after some nibbling on the mill and some judicious filing.

Geoff

Hi Again Tug,

Just seen the pictures.

Excellent thanks

Geoff

Hi Tug,

Thanks for your reply.

I can see how a collet driver will be locked very tight on the shaft.

If the driver is not REALLY secure on the shaft then it may shift marginally and loosen the nut. Does that make sense?

In the design above the driver is screwed onto the shaft and then presumably it locks in place when it butts up against the end of the shaft, but perhaps not secure enough to prevent it coming free and loosening the nut.

After your comments I'll look at the collet option in Ron's drawing

Thanks again Geoff

Good project this I'm enjoying it!!

Edited By geoff walker 1 on 23/07/2023 12:42:02

Hi All,

Ron's drawings show three options for the crankshaft. This is one of them which I believe is Chris Boll's original design.

I like this one and will probably use it.

Ron points out that using this design "may" result in a "thrown prop". What is a thrown prop?

With particular reference to this engine has anyone any ideas how this design may result in a thrown prop.

I'm just curious, the design seems sound to me but perhaps I'm missing something?

Geoff

Hi All

Well I'm making a start on this engine, so more questions to come.

I' intend to do all the machining on the sherline lathe which is fine for most of the parts.

I decided to bore out the crankcase using the four jaw chuck. The length of the case was I thought a problem as supporting the work would be difficult. I therefore decided to to split the case into a lower and upper half to make the machining more manageable. The lower half has a recess to accept a register ring on the upper half.

I'll need longer head bolts as the threaded anchor points will be in the lower half of the case with clearance holes in the upper half. The register is a very snug fit but I still plan to silicone seal the joint on assembly.

More post in due course hope this is of interest

Geoff

.......and here is another recently made tumbler reverse for a myford M type.

Complete with acetal (delron) gears.

No two cast iron gears mesh in the fine feed set up shown (214 t.p.i.)

The drive is very smooth and very quiet.

Very impressed with the physical and practical properties of acetal, easy to machine but very tough and in my opinion entirely suitable for replacement gears on a lathe of this size.

This tumbler is here to stay!!!

Geoff

Is it Westbury's? ..did ?Blackgates used to do it? ..or Reeves ..I can still 'see' the line-drawn ad that used to run in ME/?MEW

Just looked up the writer called "NED", and found that it is indeed Edgar T Westbury. So yes an E.T.W. design.

Geoff

Hi again Steve

This is page 473 from 2092

Geoff

Edited By geoff walker 1 on 09/07/2023 17:13:20

Hi Steve,

The first 1/4" drill you asked about was covered in a series of articles in M.E.by the writer "NED".

It commenced in issue 2092 on June the 12th 1941.

It continues in 2094 and 2096.

I have those three magazines, if you would like them send me a p.m. and I'll post them to you.

The build is not complete and continues in 2098 and probably at least one more issue.

Geoff

.....and my golf club has a sign near the practise putting green,....."PRACTICE PUTTING GREEN"

geoff

Hi Gents,

Thank you for your replies.

My gut feeling was that Ron's drawings would be reliable, but nice to have that confirmed

I'll keep posting on this thread with progress as I go along and of course I will have many questions.

Thanks again Geoff

Not sure about some of the "americanisms" on Ron's drawings. A cylinder MUFF, MUFF? MY Nan used a muff and I muffed a lot catches playing cricket, but an engine part!!!!!!

HI all,

I'm looking to make a start on this engine, but before I do an enquiry about the Ron Chernich drawings on the internet.

I have many questions about this engine and the drawings which I will ask in due course.

For now though just one about Ron's drawings. Are these drawings generally speaking "good to go" i.e. no major issues or omissions.

Any comments most welcome.

Geoff

Hi Keith,

Very nice indeed, well presented, and if I might add, for me inspiring.

I have been considering what project to make this autumn/winter and as it is some time since I made an i/c engine (a whittaker firefly) that will be my choice. After seeing your work I have opted for the Boll aero 18. Just planning and preparing at the moment. When I start I'll open a file as I imagine I will have some questions.

Well done again

Geoff