Little and large - building 2 vertical steam engines.

[zeeprogrammer]

Must...look...away...

Else I will get bitten.

[Jasonb]

It's a bit like a No 1 or even the original No7* which have one main standard held by two fixings and a brace, in this case the brace goes between the two standards rather than back down to the soleplate.

* originally the No7 was like the No1 but they put it on an A frame standard and called it the 7A, the original No10 was the same and only became the 10A when put on teh A frame standard.

[Jo]

It's a bit like a No 1 or even the original No7* which have one main standard held by two fixings and a brace, in this case the brace goes between the two standards rather than back down to the soleplate.

* originally the No7 was like the No1 but they put it on an A frame standard and called it the 7A, the original No10 was the same and only became the 10A when put on teh A frame standard.

It is nothing like a No 1  or the 2, 4, 7 or 10 each have a flat parallel guide to the side of the cylinder that new engine has a circular guide akin to cutting off one leg of the modern A frame. The original No 5 had two legs with a flat parallel sided cross head between them not the modern A frame circular guide/crosshead

Jo

[Jasonb]

By Similar I meant a standard on one side and the turned post on the other, was not refering to trunk or flat guides, both have the standard fixed with two screws and the post so the 7V will be no weaker as the question was about the strength of the standards fixings.

[john mills]

This is my no. 4.I don't have a build log as this was back when it was still the original start turner 

[Gas_mantle]

Thanks John, great looking engine 

Do you ever run it on the hot stuff ?

[john mills]

This was the first stuart turner engine i built it has always run on the real , hot stuff   .it doesn't run as fast smoothly like the  5a but still runs well. Piitty it has not got balance weights like the 5a.

[Gas_mantle]

Thanks, I did wonder about adding balance weights to my no4 replica, I intend to try and make the crank from solid and with have a think about it.

Progress has been slow this week but I thought I'd show just a few photos of where I'm up to so far.

I've now partly made the sole plate from a cast iron block. The trunk guide I bought is more irregular than I thought at the feet so I decided to take the back to front step of evening up the guide as best I can then mounting it on the sole plate and machining the plate to fit 



With soleplate channel milled out I've now set about mounting the guide to run true to it, tomorrow I'll try and get the detailing cut on the soleplate now that I can see where the trunk guide sits.

[john mills]

looks like your making good progress.
The first engine i made was similar to a no 10 v  that i turned from round bar so had full disk crank webs ,that also runs smoothly.

[Gas_mantle]

Thanks John, I'll have a think about how best to tackle the crankshaft over the next few days. I'd like this engine to be reasonably powerful (possibly to drive a dynamo or a decent sized boiler feed pump) so I'd prefer a solid crank if possible.

I'm pleased to say the soleplate is now largely complete   I wanted radiussed corners where the raised parts rise up so I decided first to cut channels using a 4mm ball nose mill.



Then mill away the 4 corners



A 10mm dia end mill had just enough depth to cut out the centre and give a suitable radius in the corners



That takes me to this point, a little bit of emery should tidy things up a bit so I'm quite pleased so far.







I'll try and get the side tapers cut tomorrow then that should will complete the soleplate 

[Gas_mantle]

While the toffs were getting married I thought I'd finish off the soleplate, so it's on to cutting the shallow side tapers.

I only have 1 small angle plate and little in the way of mounting hardware so holding this part proved to be a challenge but eventually I settled on this arrangement of 1 vice held in another, it looks a bit unstable but is more solid than it looks and I only have a small amount to material to remove.



To cut the end tapers would have too much sticking out of the vice so I chose to mount my mill vice on its rotary base and set it about 5^o off parallel.



It seems to have the desired result 



Final job is just to mill a small amount off either end to the correct length and ensure they are even



That takes me to the final result





I'm quite happy with the result, there are a few dwell marks but I think they'll polish out and it does at least resemble a casting.

It's not till you see a no4 and a 10v together that you realise how much the size difference is.



Next job will be to make the bearings and have a go at cutting the crankshaft from solid.

[10KPete]

Nice work! I like the fabricated upright part...

Pete

[Jo]

It's not till you see a no4 and a 10v together that you realise how much the size difference is.

and the 4 is rather smaller than the 5A or the Swan

Jo

[Gas_mantle]

and the 4 is rather smaller than the 5A or the Swan

Jo

When you decide to raid your fondling casting cupboard and sell me a set of castings I might have a go at making one 

[Gas_mantle]

Although I'd intended making the no4 crankshaft next I had a change of plan and decided to make the cylinder next.

I was lucky enough to buy a casting from another forum member at a reasonable price and this was the first time I've machined a cylinder from a casting so wasn't too sure how it would go. The outer edge of the flange is pretty much the same diameter as the trunk guide to so it seemed to make sense to get that running as true as possible and not worry too much how the bore was.

Some people complain about these budget brazed carbide boring bars and I guess some are better than others but this one usually does a decent job and doesn't suffer a lot of spring back



Once bored out to the required 1.5" dia a cheap and cheerful cylinder hone in the tailstock gives a good finish





A quick milling job to prepare the port face and the exhaust gland boss.



I don't know whether is usual practice with Stuart cylinder castings but this one has the ports and passages leading to the cylinder bore cast in but the exhaust port needs to be cut by the builder. The port needs to be ¹/₄" wide but I wanted the corners as square as I can make them so I used my smallest slot drill of ³/₃₂"



So far so good 



I don't have a ¹/₄ drill for the exhaust outlet but 6mm sounds a good substitute.



That takes me to this stage, I'll drill for the end covers and valve chest once I've made them.



There is a small cavity in the casting at the edge but if I remove any more from the face I'll start eating into the gland boss, once I have a gasket fitted I don't expect there to be a problem



All being well I'll get the end covers made tomorrow, the only slight snag I can see is there isn't much material to hold onto when turning the top cover but I'll come up with something.



Peter.