Member postings for Old School

Engineering skills at home and the ability to make things is not the sole domain of the model engineer others out there would also like theses skills for there hobbies just look at the non loco subjects on this site.

In my experience the term model engineer is very specific its someone who builds and runs steam loco,s the rest of us model makers don't fit that classification according to my ex club members. I did try hard to fit did the Santa specials etc but when I put my flash steam hydros on the stand it was made very clear that they were not representative of the club and not wanted. So I probably fit the maker group better other than being retired. It's going to be quite an interesting experience for me when I give a presentation to SMEE on tethered cars.

It will need to be a good motor to be capable of running up to 30,000 rpm. I prefer something that is non contact.

I like your idea Les Jones1. The engines that I am testing are 2.5cc two strokes glow plug ignition with tuned pipes rpm is around 42,000 the life time of a liner and piston is measured in minutes. I will be making changes to the pipe length and fuel supply whilst the engine is running what I am looking for is the change in rpm up or down due to these changes. It's so much easier to read a pointer rather than scrolling digital numbers. Les how do I generate the pulses for the tacho. Thanks for the help.

I race tether cars and I want to do some engine development in my workshop. The engines and tuned pipes are going to be run in a bench mounted test rig using model aircraft propellers as the load. I need to measure the rpm of the propeller or from the reduction gear box. I want to build the tachometer into the test rig and have a display I can easily read like a a full size car tacho. The tachometer needs to be capable of working to 30,000rpm. Where can I get one of these or can someone point to ready made modules that I can asessmble. Thanks for any suggestions.

I build and race tethered cars, the only measure is the speed you achieve apart from passing scruteneering. I use whatever technology is available. My workshop is manual but if I can get a part cnc machined chassis I do, for welding up tuned pipes I use a local specialist tog welder etc. I don't consider myself a cheat and many would not consider me a model engineer. But I enjoy the competion with fellow racers.

Worked as a UK expert and Chairman of a working group for BSI not putting them down just stating a fact far to many are copied these days. Also as a working group member I used to get a free copy of any standards I work on.

Edited By Old School on 02/08/2016 20:56:44

Most standards used in the EU are Euro Norms each country publishes it own standard with a national forward for us they are BS EN and for France they are NF EN etc, so in reality BSI sells quite small quantities of standards. Most of the experts BSI uses come from industry and a large part of the costs of these experts is paid by industry. For us to supply product into Europe we will still need to find some way of CE marking a lot of it is done by manufacturers who are allowed to self certify under a scheme run by BSI. It going to take some sorting out.

Thanks John I only have the gears that are fitted to the lathe I can make the stud, can I use standard Myford ML 7 gears as replacements for the missing one So?

Thanks Alan I have read that in my manual what I don't know is what the stud assembly looks like and where it fits on the lathe a picture of the stud and how it all goes together would be great help.

i would like to cut some 0.5mm pitch metric threads on my imperial lathe the manual is a bit vague to me anyway. Help required please.

Escapement were always oiled on the clocks built by my father who spent most of his life as a working clockmaker, Skeleton clocks always went under a glass dome so dust was not really a problem. A rate of 2 minutes a week is very good I used marine chronometer when I was at sea and a good one was about 20 seconds a day but they did everyday.

Nice work on those engines, may I ask where you got the castings for the Sogden special from I have always wanted to build one from when I was at school and that's a while ago.

Oliver

Stew nice work on the pair of cylinders what lathe and or mill did you use.

It depends what you want them for Tracy Tools are the cheap and cheerful end of the market and can be a bit hit and miss on quality. I prefer to pay more for quality taps and dies for the work I am doing Rotagrip have a huge range of odd ball metric taps and dies service is good and the quality very good.

The rpm gain of 300 to 400 sounds interesting, I have seen modified ball races that have crowded balls but this was to stop the damage to the engine when the cage failed. I have always used "plastic" cages and have yet to have a failure. To me the ball races loose the smooth feel quite quickly but they are being run at the top end of their performance range just over 40k in my 3.5cc engine and I doubt they get enough lubrication being a two stroke and the rules only allow 80/20 fuel.

I use a company called M Machine Metals they have a large range of metals always helpful quick delivery and good prices. Nothing is seems to be to much trouble have even offered to get a bar of steel in and cut off what I wanted.

Had a look at Kennametal no joy can anyone one else help or do I make one its not going to be taking big cuts. Would mild steel do?

I have got some PCD tips ref TPGW080202 and I need a holder for them any ideas where I can get one.

I want to use them for the turning of the outside diameter of pistons made from aluminium with a high silicon content

Thanks Oliver