Textile Mill Diorama

[b.lindsey]

Thanks John. I should have recognized it but now I know 

Bill

[J.L.]

You are very welcome Bill.

The water pump is a nice visual on this engine, but that's all it will be. I think it has every angle known to geometry in it somewhere. A suggestion was made to use a 4-jaw chuck to hold it.

I am using the milling machine as much as I can.

Two internal balls in conjunction with a ram lift and deliver water. Water is sucked up from below the engine. Because textile mills were often located near water, water would be drawn up into the pump by pipe from a cistern, a mill pond or a nearby river.   So on the model a pipe goes down through the floor.  I think a steel floor plate will be in order.

Note that the casting's face is "off" the centreline at this point.

[J.L.]

I thought I would take a rare one-time shot of the engine dismounted from its diorama setting. It had to be removed and  placed on the milling table for the drilling of two final holes for threading.

The feed pump will be mounted on its pad with two threaded studs. You can see them to the right of the crosshead.




 

[wagnmkr]

Looking pretty sharp John!

Tom

[J.L.]

Thanks Tom.

I had a serendipitous experience with the drilling of three equidistant holes around a false flange. I turned the brass flange out of a piece of hex stock. So when it came time to dirll the holes, every other hex point indicated the location of the holes!

Totally unplanned.

The last photo shows a pipe threaded into the flange and stopping. It doesn't. The pipe is threaded further down to engage in the part to which it appears to be attached by the three steel bolts.

A little bit of smoke and mirrors there.

[J.L.]

Since I have been working with piping and flanges, I wanted to mention that where I fall down most with historical accuracy is that I do not use proper bolted pipe flanges that have a flat face. Today, they are most noticable in pipelines where they lower the flanged pipes into the ground and bolt them together.

I do not know when pipefitters switched over to threaded pipes. When they did, they had to use unions where they could not rotate the pipe.

I have been using tapered pipe taps and dies. They are great for snugging up fittings and preventing leakages, but often a lot of thread is left exposed.

To get a more realistic clean shoulder with threads, I have switched from MPT taps and dies to straight ones. I also found out that 3/16" brass pipe can be threaded #10-40. The existing threads in the fittings are redrilled and rethreaded. (You can buy pre-threaded fittings with straight threads.)

Here is a PMR bronze elbow with a tighter shoulder using straight threads. I think it's a claner look.

[Roger B]

Still following along quietly and enjoying your attention to detail   

I have also wondered about the different types of prototypical pipe fittings and how much is size dependent. Maybe screwed fittings up to 150mm/6" and then flanges ?  Flange fittings are probably better for fixing to cylinders etc. I have used both although I am not claiming any prototypical accuracy 

[MJM460]

My work in the hydrocarbon processing industry followed many different Client standards.  However, generally, threaded (NPT) was used below 2 inch, and flanges 2 inch and above, though occasionally threaded extended to include two inch.

That said, larger screwed fittings are sometimes used in larger sizes for non-hazardous fluids such as potable water or fire water.  I once had to specify six inch screwed piping for a fire water system on an operating off shore platform, as welding was not allowed.  However, I seem to remember that in the end, they welded it anyway, as those large sizes of screwed threads were unmanageable.

Everything else was flanged, or just welded, and for some hazardous fluids, flanges are used down to half inch, then tubing for smaller sizes.  Unions are considered unreliable for joints that have to be taken apart many times.  Flanges, you just use a new gasket and proper torquing to get a good joint as often as necessary.

Normally flanges to join to equipment castings, though sometimes screwed bushes for small sizes such as vents and drains.

Pipes in refineries, gas plants and larger petrochemical plants are all American standard, so inch sizes.

MJM460

[J.L.]

Thanks Roger.

Thank you MJM460 for this excellent treatise on pipe and flange. This would be good material to share in an information section.

It looks as though the general rule for choosing the connection then was diameter dependent.

Appreciated.

John

[J.L.]

Once again, the square collet block is pressed into service. I find it excellent for milling, drilling and shaping round stock.

The engine's pump is now installed.

[Brian Rupnow]

John--You are doing some very fine work there.---Brian

[zeeprogrammer]

Fantastic looking engine. 

[J.L.]

Thank you Brian from one Canuck to another.

Hi Carl.
I agree. I think this is one of the nicest looking horizontal mill engines available in a casting kit. Some of the parts that would be wrought in iron or steel are cast in gun metal, but the principle parts are all there in cast iron.

Cheers...John

[J.L.]

I was not keen on bending a connecting rod to join up with the valve rod to accommodate the clearances needed for the next eccentric. I don't think that practice was prototypical anyway.

So I have made an offset knuckle that threads onto the end of the valve rod. The offset is not objectionable in the photo and may not be noticed. But it will move the con rod out a full 1/8".

With this knuckle and wrist pin made, I can now finish the delivery tube that pumps water down through the floor and over to the boiler.

[crueby]

Coming along great, very nice finish on everything.