Scale model Economy hit & miss engine builders wanted

[Charles 2010Participant @charles2010]

Thank you Jason for the information.

 

The direct link to the issue was great. I have ordered the back issue and placed a subscription of 12 months !!!

 

There is a lot of good info in the mags …

[JasonBModerator @jasonb]

Publication can be very irratic, you will get your 5 issues but unlikely to all be within 12months.

 

But there is some good stuff in there, my hit & miss is based on their zero-six plans

 

Jason

[Charles 2010Participant @charles2010]

I have added pictures to the album showing a near finished cylinder liner. What a big job to machine from solid ..It took me about 12 hours of lathe watching !!!

Also shown is a near finished flywheel.

 Can any one tell me what supports the outer end of the cam shaft as I cannot see it the drawings.

 A photo from anyone who has completed the engine of nearly so might help me too.

[JasonBModerator @jasonb]

I think the cam shaft is the same as a lot of H&M engines in that it is just a fixed pin that the cam gear rotates on, have a look at this finished one there are a couple of pics of the cam

 

http://www.stationroadsteam.com/stock%20pages/4367/index.htm

 

Jason

[Charles 2010Participant @charles2010]

All of the photos show the engine in detail. Thanks for locating them and letting me know the URL.

 

Regards Charles

[Charles 2010Participant @charles2010]

Has any one a favorite design for an oil reservoir using a clear viewing tube ? 

[JasonBModerator @jasonb]

PM Sent

 

As the previous one I sent you has not been read you need to go to the “My Account” box top left and click “my messages”

 

Jason

Edited By JasonB on 06/10/2010 18:35:36

[Charles 2010Participant @charles2010]

I shall be working on making two oiler, initially, Jason so that they are ready to fit to the top of the crank shaft bearing caps.

 

I now have a crank shaft assembled with Loctite 603 which is curing for 24 hours before I cut out the centre of the main bar.

 

So far all is progressing well .. Thanks to all who have supplied information to me here and in emails.

 

Regards Charles

[Charles 2010Participant @charles2010]

My crank shaft is now completed ( except for keyways !!!) and I have added photos to the album

[Charles 2010Participant @charles2010]

The cylinder head of the Economy engine is a very complex part.

 

Does anyone have any ideas of:-

 

1. in what order to machine it

2. how to hold it to do the various machings

3. why its spigot is 41mm OD and the cylinder liner is bored 42 mm OD

4. how to drill holes in it on a pitch circle

 

Regards Charles

[JasonBModerator @jasonb]

4. mount it on the mill table or vice if it will fit, then use an edge finder to set the head central to the x-y axis and zero the dials, use zeuz tables to calculate how far to turn the dials to get the pcd. or just punch the numbers into your DRO

 

2 If there is a decent machining allowance on the spigot then leave that long and use that to hold it in a chuch on a rotary table, bit like this , horizontal or vertical as required. The other method it to take a lump of square alloy and drill the mounting holes and spigor recess into that, you can then easily hold the alloy block while ther rest is machined.

 

Can’t help with teh actual process on that head as I’ve not got a drawing but there are a few pics of my IHC head being worked on in this album if its of use.

 

Jason

[Charles 2010Participant @charles2010]

Thanks for the info …

 

Sound like do the holes first and then use that to mount onto round block and hold in a chuck or may be  make up spacers to bolt to a face plate !!!

 

Thanks for the input Jason.

[JasonBModerator @jasonb]

Sq block is easier than round as you can just turn it 90deg in the machine vice, round block would take a bit more effort to line up.

 

J

[Charles 2010Participant @charles2010]

Good thinking !!!!

[Anonymous]

Charles,

 

I remember mounting the cylinder head on a piece of aluminium angle, for use in the 4 jaw chuck on the lathe. This allowed machining of the spigot that fits in the cylinder. Once this is done, the head can then be mounted in the vertical mill, with the DRO zero’d at the centre. Then all the flat surfaces can be machined and the holes drilled.

 

I’ll have a go at trying to find the jig later today. If I do find it, I’ll post a picture of it.

 

Regards,

 

Andrew

[Charles 2010Participant @charles2010]

Thank you Andrew ..

 

That will be the way forward…

 

I hope you can find the photo ..

 

Regards Charles

[Anonymous]

Hi Charles,

 

I’ve eventually found the jig, hiding behind the aluminium offcuts bin. Two photos have been added to my ‘Economy’ album. One is of the jig and the other shows how the cylinder head was mounted. The inlet and exhaust port faces were cleaned up and tapped M6 before mounting. As you have no doubt realised the thread callout of 1/2″ BSP is wrong. I used M12 instead.

 

Regards,

 

Andrew

[JasonBModerator @jasonb]

Any specific reason for going with M12 Andrew? I would have thought 1/4BSP a better option as the carb seems to be attached to the head with a standard street elbow looking at the pic on Engineers Emporium, can’t quite see the exhaust but looks liek a nipple and malable iron elbow, again readily available in 1/4″ BSP.

 

Jason

[Anonymous]

Hi Jason,

 

I chose M12 as I already had all the necessary taps and dies and didn’t, at the time, have any BSP threading equipment. I am not sticking exactly to the design in this area, so the availability of off-the-shelf elbows is of less concern to me than it might be to other makers.

 

Regards,

 

Andrew

[John Wood1Participant @johnwood1]

Yes, 1/4 BSP is what LA Services use to fit standard iron elbows which is also what they use on theirs – and mine.

 

Charles, lots of gen on the way to you, see separate e-mail.

 

Luck to all

 

John

[Charles 2010Participant @charles2010]

Thans John I look forward to seeing the other email soon.

 

It was nice to be ale to see a completed engine at the show yesterday and to take a lot of photos and also one being put together…

[Charles 2010Participant @charles2010]

Is spring steel necessary for two parts in the Economy Engine or has any one used anything else. ??

If spring steel is needed where does one obtain it and secondly how does one cut it???

 

Regards Charles

[Anonymous]

I haven’t made those bits yet, but it didn’t occur to me to make them from anything but spring steel.

 

I bought my spring steel from Folkestone Engineering Supplies. It comes annealed, so the issue is not how to cut it, but how to harden and temper. Not a problem for me as I have an electric heat treatment furnace. I don’t suppose the hardening and tempering is that critical, so could be done by other means.

 

Regards,

 

Andrew

[Charles 2010Participant @charles2010]

I too have a small kiln that will reach the 820C  and then quench in oil and then heat to 350C and hold for 2 hours.

 

I asve been able to find the product on that company’s web site so will get mine from there too.

 

I am now also thinking about the timber supports for the engine has anyone any ideas ??

[JasonBModerator @jasonb]

I made my skids from maple, beech would also be suitable

 

 

 

Edited By JasonB on 18/10/2010 20:28:52

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