Making Loco cylinders.

[Arnak]

Hi,

Due to the high cost of buying castings for my Virginia loco I wondered if it would be possible to purchase a cast iron square and fabricate the cylinders from that?

I have seen a supplier that sells cast iron in square form and 6" long of the required size.

Any advice would be welcome.

Arnak

[GWRdriver]

Amak,
I am not intimately familiar with the shape of Virginia's cylinders so I can't say for certain but of course it is possible, and usually cost effective, to machine many cylinder blocks from a solid. It's obviously not TIME-effective though. For the Virginia another option you might consider is building up the cylinders from steel or bronze bits silver soldered together, and in the case of steel install a bronze valve face and cylinder sleeve.

[Arnak]

Hi GWRdriver,

Thanks for the reply.

Time isn't really the issue but price is...

The best price I have found so far is £110 and from Reeves at £140!!!

Admittedly they say there are 14 components but I can get a cast iron slab 6" long for £27.

A fair bit of difference as you would agree.

I bet that it is a bit tricky milling the shape but if it seems possible then I'd prefer to go down that route.

Arnak

[spurley]

Hi Arnak

Have a look at modeleng.proboards20.com/index.cgi?board=Images&action=display&thread=1148907650 on this site and maybe PM 'Baggo' John Baguley who is the expert on this forum. Judge by his work.

I think he would be very happy to provide any guidance or background to this process as you will be able to see from looking at his pictures.

Cheers

Brian

[baggo]

Brian,
I think 'expert' is far too strong a word! You should see the cock-ups. I make just as many as anyone else.

Arnak, I'l be happy to help if I can. Andy (Greasemonkey) also has some pics of the steel cylinders he fabricated for his Dougal here:

modeleng.proboards20.com/index.cgi?board=Images&action=display&thread=1165062147

He may be able to help as well.

Assuming you want to stick to cast iron, Live Steam Models list 50mm square cast iron at £1.87 +VAT per 25mm so enough to do the two cylinders should only cost about £11 plus postage. If you are happy to use bronze then you could use cored bronze bar for the cylinder and silver solder a bronze slab on the top for the port face. This method also allows the ports and steam passages to be machined before the two are fitted together (much easier than drilling them afterwards) Mounting lugs could be plain brass. The steam chest can be made up from 4 brass sections soldered together with bronze bosses soldered/screwed in for the valve rods. The valve chest cover can just be brass sheet. I never can understand why these come as castings when all you do is machine them until they are just a flat plate! Cylinder end covers can be turned from brass bar with a bronze bush for the piston rod. Probably cost you about £30 for both cylinders!

John

[Arnak]

Hi Gents,

Thanks very much for the tips and advice.

I'll look into both of your url's and be sure to get back for some advice.

Remember an expert is someone who who can correct his own mistakes.

Arnak

[Phil Sutton]

No,no,Arnak,definition of an expert is:

Ex.............Something that used to be

Spurt.........A drip under pressure!

Never ever be an expert!! ;D ;D ;D

Phil

[Nigel Bennett]

Chap in Finland has been busy fabricating cylinders... www.saunalahti.fi/~animato/3003/060o.html
Interesting way of doing it for piston valves.

[jeffhills]

Arnak
I have just done a pair of 5" cylinders out of 4" dia cast gun metal, the total cost of materials about £150 against £400 for a set of castings. I t has taken about 40 hrs of machining, but that is supposed to be part of the fun. I will post some photos later.
Jeff

[Deleted]

Hi
Have a look on ebay, I think there is a pair of cylinder castings on there at the moment.
If you just get the main blocks you can always make the covers, steam chests etc to go with them.
regards
Trevor

[Arnak]

Hi,

Thanks for the url, the pictures are very informative.

I look forward to the pics.

I guessed it would take a long time to make the cylinders from solid but so what it's only a hobby... Did I just say that?

Arnak

[GWRdriver]

I really have been astounded at the prices being asked for castings these days. But then I can remember articles in old ME's where someone thought 30s/6p was entirely too much to ask for a full set of wheel castings so mild steel plate was acquired and the "castings" were created using breast drill, hacksaw blade, and rat-tailed file.

[bobpendleton]

gwrdriver said:

I really have been astounded at the prices being asked for castings these days. But then I can remember articles in old ME's where someone thought 30s/6p was entirely too much to ask for a full set of wheel castings so mild steel plate was acquired and the castings were created using breast drill, hacksaw blade, and rat-tiled file.

Was it ever thus? ME No. 1429, Sept. 1928 has a letter by R Hogan referring to a recent 'homily' by LBSC regarding the cost of parts for model locos. He (Hogan) says: 'the prices asked (--) are not what they should be... It is common to be asked anything from 7s. 6d. to 12s. 6d. each for cylinder castings yet the cost of a pair cast locally off one's own pattern in the finest valve metal, is 3s. the pair when bought by weight'.

I hasten to add that this is totally outside my own experience, the magazine being nearly ten years older than me! Quite by coincidence I was reading the magazine within 20 minutes or so of seeing Harry's note.

Bob

[stantheman]

While I may agree that the costs of many items we use for our hobby are highly priced, the equation for comparison is a little out of balance without the other side of the coin! namely, 'how much was the average model engineer from 1928 (say in this case) earning per hour/week/year? I have recently bought items, which when sourced from a variety of places, have shown a remarkable difference in price, some very often being made by the same manufacturer. All the best with this project using whatever method suits you Arnak.

Stan.

[steam4ian]

G'day all.
Fabricated cylinders are nothing new, they have at least one prototype precedent. The 520 class 4-8-4s of the SAR (Ozzie not RSA) were built during war time, 1942, when castings were difficult to get. The 20.5" x 28" cylinders and half saddles were fabricated entirely by welding. I think the cylinder and valve liners were cast iron inserts.
The 520's were no slouch obtaining 2600 IHP at 78 mph; not bad for 66" drivers and 32000lb T.E.
I another post showing beautifully machined cylinders from solid, the ports are still drillings; at least with fabricated cylinders they can be built in.

One good turn derserves another.
Regards.
Ian

[mmaidnz]

Hi,Arnak.I don't know what shape or size your cylinders are,but I made a pair of sweet pea cylinders out of solid 5 1/2"bar.
The roughly square shape was first cut on the bandsaw.Then 4 sides faced,so i would have a reference surface.then the single odd surface milled.On the second cylinder,I bored it BEFORE milling the last face,as that made it much easier to hold.
The basic material cost was $50NZ for approx 12",51/2" diam.These were offcuts,the normal retail cost would have been more like $150!(about 50 pounds).If you have folding stuff in your hot little hand,bargains can be had:D.
The leftover bits from the cutting were used for the covers and other small parts,so the waste was minimal.
Like you said,time used was high,but of no consequence to me.

[ilvaporista]

Being know as a 'little tight' when it comes to spending hard earned pennies I went down the machined from solid route for my 5" Hunslet.

The CI for blocks, valve chests and covers came out at £28 as opposed to the £125 for castings.

As I was reluctant to just machine away excess metal I used the horitontal/vertical bandsaw to get as close to final shape as I could.

I cut to within 1/16" of the finished shape with the bandsaw.
To use the bandsaw to cut to shoulders I gripped one of those tilting vices in the holding vice of the bandsaw in horizontal.
This allows you to keep the face parallel to the bottom of the blade. In this way I had enough pieces left over to make various other parts.

As the saw did the most of the work I also saved machining time and could get on with other jobs. Result one happy bunny.



I tried to post a sketch with this but it did not work.
C:\Documents and Settings\adrian\My Documents\personnel\block.htm[/img]

[Arnak]

Hi Folks,

I think that after reading all these most useful posts I will go down the route of buying some CI in square and machine them from solid as that is the cheapest option.

Once I have finished the cow catcher which is being a right pain to make. 8-((

Then it's axle boxes, eccentrics, wheels then hopefully cylinders.

Arnak

[steam4ian]

G'day Arnak.
Good to see you're starting at the front (Cow catcher). Is the pilot beam next?

Regards,
Ian

[Arnak]

Hi Ian,

No, I thought I'd make the tender chassis next. )

I have the front bogie, frames, springing all sorted so I just fancied a change before I started the wheels etc...

Also I wanted to try out my new miniature brazing torch, works very well thank goodness.

Arnak