Member postings for Roderick Jenkins

I think there's a button press missed out in the above sequence.

So, in Y:

Find one edge, press Yo

Find other edge, press 1/2 then Y (not Yo)

Move back to zero, this should be the centre.

Hope this helps,

Rod

Edited By Roderick Jenkins on 30/09/2023 11:05:47

In summary, MACHINE reamers cut a sized hole from the tip whereas HAND reamers cut a hole that is only to size about half way along the reamer onwards. You can't cut a blind hole to size with a hand reamer. ARC sell both.

Rod

In my experience ccgt can provide a very fine surface finish on most materials, including brass. However, the large positive rake means that if you try too take too deep a cut they can grab and pull themselves into the cut with unpredictable results.

Rod

Duckduckgo often finds things that Google is too busy pushing revenue earners to bother with

This may help **LINK**

It gives the max temp as 950C

Rod

As in Jibraltar

I'm from the soft south so jib for me but my Brummigen neighbour, who was a professional mechanical engineer, was a hard G man.

Rod

Well, actually: Milling Operations in the Lathe

Rod

Nice work

Rod

When I did the 1" bore cylinders for my Hoglet I held the cylinder block in a sc 4 jaw chuck to bore the cylinders then used tailstock support while I cut the fins with a parting tool. It all went very smoothly. I used the same method for my air cooled Farm Boy. My Matosa rotating centre is bigger than the bore but if you have a smaller centre then you can turn up a plug to fit the bore and centre on that.

Rod

If you are trying to determine the spring force that you need to keep the cam follower in contact with the cam then you need to know the weight of the valve gear being moved and the acceleration due to the cam at the maximum speed of the engine - Force = Mass x Acceleration. If the cam has a flat follower than CamCalc can help give a figure for the theoretical maximum acceleration which will act as a starting point for determining the correct spring size.

CamCalc dropbox link

Rod

Arceurotrade have some useful information Here

HTH,

Rod

Lest anybody gets put off making small "diesel" engines, an internet search for "model diesel engine fuel uk" will show several model shops who will sell fuel for delivery by courier. Not cheap - Model Shop Leeds will sell you a litre for £20 plus a tenner for delivery. Not really expensive compared to the cost of materials these days. I've still got half a tin left from the the Dyno I made a few years ago but I expect all the ether content has evaporated by now.

Rod

The other variable to consider on 3 phase motors is: how many poles?

What are the trade offs between torque and speed?

Rod

John,

I've sent you a PM.

Rod

Anthony, your fastenings chess set is utterly charming

Rod

Thanks for the comments. My tentative plan is to make a pinion cutter from silver steel backed off with my Eureka tool. My fear is that EN24T may be a bit much for the carbon steel cutter. I note Ifoggy's comments about hardening EN8 and have referred back to a previous thread. I do have a small electric furnace and made Lammas' hardness tester so maybe some experimentation is called for . Or perhaps I'll stick to lantern pinions.

The recent talk here on simple clocks has led me down a rabbit hole and piqued my interest for the next project.

Rod

Does anybody have any experience of using EN8M (212M36, 1140) as an alternative to the no longer available free-cutting silver steel for making pinions (or, indeed, anything else)?

Cheers,

Rod

Guys, I think we need to be a little more rigorous with our terminology here. Most 3 jaw self centering chucks actually have good repeatability, it's the concentricity that is variable for different diameters. If you measure the run-out of a piece of round stock, take it out and replace it using the same pinion and orientated against the same jaw then the run-out will measure pretty much the same as before. You can use this property to make an accurate and repeatable split collet bored in situ.

In Sonic's case, I assume that he has a 3 jaw chuck that is a trial to remove and re-attach: if so I can understand his pain. In my experience ER collet chucks are not that hard and can be turned with a carbide tipped boring bar so I would mount the hex collet block in the 3 jaw, true up the tapered collet seat using the top slide set to the correct angle using a dti. Mark one of the hex sides so that you know which side goes against which jaw and remember which pinion is used to tighten the scroll. You should now have good concentricity and repeatability. Worth a try I think.

Rod

I used a 1/6 HP induction motor on mine. When sizing the pulleys don't forget that the manufacturer's recommended top speed is only 1000 rpm.

Rod