Member postings for Old School

My father was a clock maker made a living making clocks from scratch everything was done in the workshop at home . He used a Sievert type torch with a couple of different sized burners. I have it now and still use it. Not into clocks but still have most of his hand tools.

I had a Terrco gunstock copying machine it would do very accurate work but it wasn't cheap. I imported it from America.

Tug

The reason for the sloping bases of some twinshaft engines is the back of the cars they were fitted in the base of the car sloped up so when the engine was installed it was level in the car. Have a look in Oliver story book.

All the engines I have used have had a "U" shaped bracket to hold the engines in and retain the engines lugs see the cobra car picture.

Perhaps it might be worth thinking about the csr it's going into before you remove the lugs.

Oliver

On the subject of engine cooling, this is a modern 1.5cc tether car engine it has no cooling fins and the car has no flow of cooling air into it other than what the engine needs to breath.

Edited By Old School on 02/01/2020 13:23:38

Tug

On your engine drawing you have a bolt hole in the crankshaft for holding on the hubs. It's common practice to use a male thread. The wheels need our be done up tightly they have a nasty habit of coming loose.

Picture of the Oliver copy wheel hub.

Oliver

Pictures as promised

Tug

Tether cars run for a relatively short periods of time, currently the distance they are timed over is 500 metres plus the time to warm up and get to speed at the end of timed run the cars are shut off.

Most of the twinshaft cars are semi scale single seat racing cars grill in the front and vent out of the cockpit, like the Oliver Tiger two five car in the picture. The car is an aluminium casting which the engine is bolted to this works as a heat sink for additional cooling.

i don't think it is necessary to change the fins on the engines, I have never had a problem with any of my twinshaft powered cars and they run for quite long periods.

I will put the pictures up later got to nip to the dentist.

Jason

Yes it is a shut off, both cars have them operated by hitting the bristles of a brush.

Oliver

A Chinese copy of an Oliver Tiger Twinshaft and a Eureka engine same as the one in the Cobra car.

Not all my cars are fast the two in the pictures are ones I run at Great Carlton track, they are a simple flat plate chassis with a tinplate toy car fitted these are probably of Chinese origin.

The engine is 2.5cc diesel of Eastern European origin of modern construction ABC liner piston schnuerle porting ball raced crankshaft of normal aircraft construction.

The wheel hubs have been extended to fit the car body.

This is a 2.5cc diesel again but a Russian copy of an Oliver Tiger twinshaft with a bit of work they go well, this one needed the piston lapping to fit the liner way too tight.

The wheels are much closer together on this car, and the plit collets go straight into the wheel hub, same a model aircraft engine.

Tug

A 2.5 cc diesel would not be competitive in today's tether car racing they were capable of around 100 mph the current world record for a modern 2.5cc tether car is around 177 mph. The car and engine were built by by Torbjorn in his workshop at home a very skilled engineer.

Oliver

Tug

The car in the foreground is a replica of Ian Moore,s Shadow it is powered by a mk3 Oliver Tiger minus the mounting lugs.

The advantage that the gearbox gives you over a twin shaft engine is that you can run much bigger tyres for example on a twinshaft diesel 58mm diameter and on the shadow 70mm diameter. Gives you more freedom in designing the car and easier push starting of the car.

The only classes that exist at the moment are for the modern cars and they are restricted to a fuel with 80% methanol and 20% castor oil, so no diesels.

All is not lost a track is being built at the BMFA,s Buckminster site, it's being funded by tether car enthusiasts, the outer running track concrete has been poured and the apron and centre will be poured in the new year. SAM 35 has been involved and it is planned that initially old timer cars will be run, diesel, spark and glow engines classes 1.5cc, 2.5cc, 5cc and 10cc.

A new thread might be a good idea.

Oliver

Edited By Old School on 29/12/2019 18:57:52

Edited By Old School on 29/12/2019 18:58:49

John MC

The crankshaft and front bearing housing has not really changed from the Nalon Viper. The performance from the engines has significantly improved over the years. In the tether car world the crankcase is still aluminium but the front housings are steel with press fit bearings C3 or 4 clearance with ceramic balls.

Various designings of front housing are in use but they all seem to have a very similar performance. I am looking forward to seeing your engine design anything new is worth a try, I will build your front end and put it one my engines and run it on the test rig to see how it compares to what I am currently using.

John

Its one solution, if it was as good as you say it would be in use in miniature high performance engines but not everything scales as we would expect.

i would be very happy to be proved wrong. As for C3/4 bearings yes they are in the bearing manufactures catalogues but try buying a small quantity no chance.

Bazyle

You have made a valid point over multiple devices, both our iPad devices are struggling even with the available speed. Look like I am going to have to visit the January sales.

Vic

It is definitely the iPhone and iPad mini, the laptop at the other end of the house is 3 times as fast all on wifi not hard wired.

The internet speed is available in the house on wifi I want to be able to use it.

My modeling interests are all about going fast, no reason for the computer devices not to be fast also.

David

The router is new and it gives the 69 via wifi to my laptop at the other end of the house.

John

Yes they need upgrading, but what are the options other than Apple which cost a fortune.

I have had BT round to sort out my internet connection it was slow 18 when measured on a speed checker. When they sorted the problem new line required it gave a speed of 69 according to the engineer my laptop agreed. But my IPad mini and my iPhone both old still only gave 18.

Seems like I need a new phone and iPad mini, I could buy another lathe for what that lot will cost me. What are the options?

John

As you say the best F2c engines are coming out of the Ukraine and Russia but these are diesel and the class is fuel limited so not maximum performance a compromise between speed and distance.

The all out 2.5cc power class is F2A speed glowplug engine with tuned pipe exhaust systems running with the engines reving around 40,000 rpm and the best one is built in this country BR Irvine engines th Profi from the Ukraine is catching up.

Graham

My interest is racing tether cars the smaller classes1.5, 2.5 and 3.5cc these rev around 40,000 their life is short.

Most of my work is modifying existing engines, making new pistons out of high silicon content aluminium etc.Crankshafts I have made in Hungary and liners chromed and ground in Russia.

My workdhop is fairly standard model engineers one Myford 254 lathe, Seig X3 milling machine and drilling machine bench grinder plus a tool cutter grinder. The latest addition is a Seig KX1 cnc mill.