Cylinder Boring Techniques for Steam Engines

Hello Will, Tardy of me not getting back to the forum quickly, lots going on with the bees and I had to go to a bee keepers apiary to sort out what was happening. He had united four hives into two and it was all wrong and he wanted another Nucleus as well. Alls well now and I onkly hope he stops manipulating the bees so they can get on with what they do best !

Looking at the choices of metal, first go for the Mehanite Spheroidal. the choice of metal for the spool as you call it, is of course the s/steel and then the free cutting mild steel, equivelent to our EN1 I think.

Buy a length of each and even if you dont use all of it, it is still useful.

The flexible steam pipe I dont know but hopefully someone will read this and have an idea, I have not seen flexible pipe in small dia. that we might use.

I am going to clad the boiler with some thin insulation blanket which I have now found and then cover it wih a metal covering. Lots of work involved and fine detail.

I am afraid bee keeping has raised its head again as I have an order for some more bee boxes to make, so everything goes on the back burner while I do them.

Shortly I will be taking honey from the bees and having to spin it out and filter it, too hot at the moment as we are sweltering with 29C here at the moment at 2030hrs. We are not used to it at all.

Clive

> Shortly I will be taking honey from the bees and having to spin it out and filter it, too hot at the moment as we are sweltering with 29C here at the moment at 2030hrs.

Hi Clive,

My wife says "Lucky you!"

Hi Will,

I'm not sure your choices are as critical as you fear. Ductile cast iron is abit posh for pistons, in theory that with plenty of graphite should be more tolerant of poor lubrication and may be more likely to form a hard, black glaze that resists further corrosion.

I'd go for stainless for piston/valve rods, just as a matter of habit, but meake sure teh surface finish is very good or they will tear up O-rings or other gland packing.

Neil

So you are somewhere in Switzerland, buying from Mr. Burkhard?

Regarding your list of materials: stay away from St37 when you can. It's usually called 'garden fence iron' here and difficult to get a good surface finish

Also for a piston I think GG25 is possibly better suited than GGG60. The latter would be good for highly stressed machine parts (wheels, gears). It is much stronger; I think the number gives the tensile strength in kg/mm2.

Greetings, Hansrudolf

Hi Clive and Neil,

Thank you very much. I don't fully understand Mehanite Spheroidal (Sphärogußrundstangen Kugelgraphit I think) - does this referr to the way the iron is cast and the resulting crystal structure of the graphite?

Will reply properly ASAP.

Will

Hi Hansrudolf,

>So you are somewhere in Switzerland, buying from Mr. Burkhard?

I think so - I get the impression that he supplies the kind of metal stock I'm after and that he doesn't mind handling relaitvely low-value orders. I've still got a lot to learn though. Thanks for the advice about avoiding St37.

Hi Neil and Clive,

Great to hear you've got some good weather. The weather has improved here as well, 27 degrees all night last night. In Scotland I reckoned that it was impossible to sleep above 20 degrees but the Alps forced me to change my views on that. I remember my great uncle's equipment for spinning honey - miss that a lot.

Thanks for the advice about surface finish - I'll give a lot of attention to that - I think it will take me a few attempts to get it right - any suggestions?

It sounds like a lot of work sorting out the wrongly united hives - hope the owner does leave them alone now - some people have a terrible urge to interfere with nature until they mess it up.

I might have a try with silicone hose for dairy systems - fairly resilient stuff to withstand sterilisation by hot water and aggressive chemicals - small diameters were used for the vacuum lines.

Will

Meehanite is a cast iron with (i think) a little nickel added and heat-treated for several days after casting to give a fine, easy machining, ductile end product. It is a pleasure to machine.

Neil

Well I really hope you know where you hang your hat...

Yes I know my question was a bit awkwardly formulated. We foreigners don't know every trick, sorry...

How do you like:

According to the fact that you buy from Me. B, I suppose you live somewhere in Switzerland, is it a secret whereabouts?

Greetings, Hansrudolf

Hi Neil,

Thank you very much. That definitely sounds like what I'm after. Am I right in thinking that Meehanite Spheroidal would translate to "Sphärogußrundstangen GGG 60 Stranggegosen, Gußeisen mit Kugelgraphit" not "Graugußrundstangen GG 25 Gußeisen mit Lamellengraphit, geschält"? I really struggle to understand the German descriptions of metals.

One component I forgot - the lubricating oil. Can I use the 10w-30 part synthetic engine oil I use for my turbo diesel or would another oil be more appropriate?

Will

Niel, just to let you know I took 63lb of honey from two hives and got two stings for it ! Very nice quality as well.

Hives and bees doing well. I have another three to do yet.

Clive

Hi Clive,

Congratulations on the honey and the health of the hives - a great outcome in such a poor summer!

You mentioned that you sharpened your Cobalt boring tools using diamond stones. After sharpening, do you finish honing the edge using the fine diamond stone or using an oil stone or water stone?

What were your thoughts about lubricating oil for a model engine? Can I use the 10w-30 I use for my turbo diesel or is another oil more appropriate?

Hi Michael,

Thanks for the link to United Cast Bar Limited - interrestign to find out more about cast iron. A lot I wasn't aware of.

Hi Hansrudolf,

I live at the North end of canton Schwytz - near kussnacht am Rigi and Luzern. I'm new to buying stock - when I was younger I just grabbed a lump of the right sort of metal from a box in the corner of the workshop - if it wasn't there I went to be grumbled at by the storeman and maybe get a lump of something which was hopefully suitable thrown at me. I never had to know how to specify exactly which alloy or where to buy it from.

Will

Hi Will,

Sharpening the cobalt boring tools, I only give them a stroke towards the cutting edge, if it was badly damaged I would go on the wheel.

At the moment I am lubricating with PTFE loaded oil which is a bit thin, but the PTFE is bringing out all the muck and then I will go to a multigrade oil, not that I will need much. 10 W 30 grade sounds about right but I think it is mostly synthetic oil now.?

Found a little problem with the piston and piston rod, when the piston is tightened onto the rod it is canting over so I will make new rods slightly longer and recess a couple of mm into the piston which will keep it straight. With 3mm dia thread it may cut slightly off and wander. I will have to turn a couple of hundredths of a mm off before I thread the new rods.

All the honey is nearly sold now, all over the UK honey production is down about 60%, personally I am down about 40%. this is a bad season, all down to the weather. We all live in hope though, a friend has lost 2 hives so far and I hear news of lots of bee keepers losing 1 or 2 hives through failing to supersede the Queen. I now have two hives left to collect from and I estimate about the same amount as I have already taken if I am lucky. Ivy is the next plant to flower and the bees will make straight for it like all the other insects. There is another plant, Marsh sage but it does not flower very well in cooler weather, my hives are very close to the tidal river and I have seen them working the Marsh sage.

Clive

Hi Clive,

So for the cobalt tools am I right in thinking just a stroke on the fine diamond stone to shapen (no need for oil or water stones). (These seem like high quality tools so I want to be sure that I know exactly how to care for them - I hate seeing tools being attacked by people who are ignorant of how to use them - **LINK** .)

Yes - the 10w30 is part-synthetic. Based on your advice I'll use it. 200 litre drum next door so no shortage of it

Should I try to use this oil as cutting oil or should I look for something more appropriate?

Thank you very much for the information about the piston and piston rod - I'll bear that in mind as I plan mine.

Very interesting to hear more about the bees. I'd never thought about how plants time their flowering in that way.

Today 150 years of steam navigation on Waldstattensee were celebrated with an illumination of the fleet. I can try to upload some (very badly made) videos if anyone is interested. It's amazing to see 150 year old steam engines still in daily use - especially given that most mechanisms made now are designed to disintegrate irreparably after a year or two at substantial environmental and financial cost.

Will

Look-a-there! Well it's Schwyz (with a long yyy), but Search.ch knows you nonetheless.Nice coincidence, just next to my garage. But the car was serviced 2 weeks ago, so no visit planned in the near future. I will send you my address via PM, so if you feel inclined you can come over for a bit of workshop talk.

Greetings, Hansrudolf

Hi Will,

I would be dubious aboyut using the Lube oil as a coolant, as its long chain polymer with the synthetic part it would get everywhere.

I use a can of WD 40 and if I want to cut wet I dispense a little into the plastic cap and use a brush against the work as the cut progesses.

The Cobalt tools very seldom need sharpening unless you want a particular shape to cut, they come with the correct geometry for use out of the box and they just do the job as is.

Clive

Hi Hansrudolf,

>but Search.ch knows you nonetheless

I suppose since they've put my telephone number online I should get a telephone...

It's been interesting living next door to these two legendary mechanical geniuses - and helping out on tasks that need an extra pair of hands. Come over and visit any time. Everything (garage, house, et all) is due to be demolished next year to build concrete flats. (I think the plan is to gradually demolish the entire canton and cover it in concrete.)

Hi Clive,

Many thanks - I'll get some WD40 and use that - nice and simple. (You're right - all those sticky long chain molecules in the semi-synthetic do make a bit of a mess.)

The Cobalt tools seem a world away from HSS

Will

Glad you still got a decent harvest Clive. I( noticed today flowers covered with hoverflies, but no bees

Neil

One part I forgot to mention. To get the steam into the valve block I was planning to simply thread a hole in the valve block then connect the piping using a Single Pipe Union (or similar). Seemed really simple, easy and flexible. Unfortunately I'm having problems finding metric Single Pipe Unions in model sises (imperial are easy but not metric). Does anyone have any suggestions?

Edited By Will Robertson on 26/08/2012 22:39:40

Hi Neil, I noticed yesterday that a lot of larger Hover flies were out, much later this year than I have seen before. Some of them very brightly coloured.

With over 300 species of Hymenoptera ( Lace Wing insects) the weather controls their life.

This year we have seen very few Wasps and my wasp trap has only caught about 3 so far where normally I would have a full trap. Unless they come very late then its a bad year for wasps as well.

I have seen no Dragon flies so far, they usually hang about the garden but then the Nymph can stay as a nymph for up to three years in its underwater life cycle.

Clive

Will, I am sure the pipe threads and connectors are not Metric but follow the Pipe Thread sizes, someone will tell us if they are not.

Reeves 2000 have a good selection of copper unions and items for pipe work.

Clive

Clive.

I had my workshop door open yesterday and a great big green dragonfly flew in to check the lighting etc. Managed to open the window turn off the lights and help him out, don't like spies checking out my bodging, probably even now having a laugh with the other dragonflies at what he was up to in there.

Alan