Member postings for CorRad

Thank you guys, feeling good about this one!

I have completed my version of the Vega twin, designed by Parker. The drawings was published in Model Engineer during the 80's. The link below takes you to a video on YouTube showing my engine. Initially, I had much concern whether I should tackle this engine. However, because there was a real prospect of using this engine in a model aircraft, I embarked on the project. There was no real problems with the machining of the parts. I just found that some design features can be improved upon and so also some suggested construction procedures and methods. The engine runs well conventional glow fuel prompting me to consider mounting this engine on a model aircraft.

https://youtu.be/fnxaEpXEy9w

Edited By Neil Wyatt on 03/09/2018 10:48:38

I have uploaded two videos of my other completed engines. The links are below: https://youtu.be/_PH-iE7YmdY​ https://youtu.be/bZX-ajNffrY

Edited By JasonB on 04/04/2018 07:20:50

Edited By JasonB on 04/04/2018 07:43:11

Correct Ian S C. Initially, this caused a problem in that the starter motor does not have enough torque to turn the engine when it is one of its compression strokes. In order to start the engine using the mopet starter motor, I have to manually turn the flywheel in the opposite direction that it normally runs, until a compression stroke is reached. When the starter motor is energised it can then build some momentum before a compression stroke is reached. This works fine and the engine is easily started as can be seen on the video.

Just be careful that the engine does not over rev the starter motor....there is a risk of bursting the windings on the armature....I know...I have done it on a car! The starter got jammed with the flywheel gear...

Thanks for that information.

Good question. When I had to make decisions about the starter motor, this did worry me. Yes, the starter motor remain engaged after the motor has started. The life time of the starter motor bushes is therefore in question. However, this allows the starter motor to be used as a dynamo to charge the battery.

Methanol is used primarily because the emissions are much cleaner. There are two 50mm diameter computer style cooling fans on the front of the engine aimed at the heads. The drawings actually calls for a sheath over these fans that result in much more effective cooling. However, the look of the engine without these sheaths appeals more to me. The longest time that I have run the engine continuously was for 10 minutes. The heads certainly did get relatively hot but not to the extend that it was considered a problem. Should I want to run this engine for long periods, I will certainly have to add these sheaths. I agree with your remark regarding the short crank.

Apology for the problem with the link. I typed the address in stead of copying the link as a hyperlink. The link below works. Thank you Joe I enjoyed the building. The engine made from car scrap is certainly very innovative.

https://youtu.be/F44qsIr_AEA

I have completed building the Howell Twin 4 stroke. The link below takes you to a video of the completed engine:

Edited By Neil Wyatt on 28/03/2018 10:42:25

I intend to start building this engine. Having acquired the original drawings published in ME, I recall that someone created CAD drawings of these. This will be very handy as some dimensions in the original drawings are missing. Is there someone who is willing to share or for sale?

Why do you want to buy piston rings? They are really easy to make. I too, were very reluctant to make them until I made the first batch. I was hugely surprized by how easy it really is. There are many descriptions accompanying model engine plans, articles in magazines and in forums on how to make them. I suggest, take the bull by the horns - you will be well rewarded.

Anybody willing to sell to me Model Engineer issues that contains the drawings of the Vega Twin? The copies of ME were: Volume 156, No 3768-78, January to June 1986.

I agree with Neil, a man got to have a metal lathe! Just some advice on the suggestion that you will be looking for a Chinese lathe: you will be selling it soon and will be looking for a well made precise lathe such as a Myford.

I agree with Neil, a man got to have a metal lathe! Just dome advice on the suggestion that you will be looking for a Chinese lathe: you will be selling it soon and eill be looking for a well made precise lathe such as a Myford.

Thank you for the good advice. Silver steel it will be.

I will be machining 4 cams for a twin 31 cc - the Jerry Howell v twin. The plans calls for the use of drillrod ( silver steel). I find machning leaded steel an absolute pleasure due to the easiness and the quality finish that one obtains. Leaded steel is somewhat softer and its resistance to wear is lower. Does anyone have any experience in using leaded steel in place of drill rod for a cam? Seeing that it is a flat surface in contact with the cam follower, is the use of the softer leaded steel really going to have a detrimental impack?

Hi Rod, thank you very much for the spreadsheet. It works perfectly for my purposes. Regards.Cor

A cam Calc spreadsheet is precise what I need right now. Unfortunately, the spreadsheet on Dropbox is not available anymore. Would it please be possible to drop it again.

Thank you

Cor

Having looked at several twin, 4-stroke, aero engines, I came to the conclusion that the VEGA Twin is the most suitable project for my level of experience and equipment. Could someone please direct me as to where to get the drawings please. Thank you.