Pansy

Been a little while since I have put a Blog up but certainly have been busy. I have been filling in the unused holes on the running boards and lengthening them over the back buffer beam. They were shy by 1mm so I have made some strips to extend them. Also some brass insert plugs have been silver soldered into the running boards. A tedious job...not quite as much work as making some new ones.

Also some brass is on order for the tanks and cab and boiler cleading top plates. Looking forward to getting that in.

Happy steaming!

Nigel

26/6 - 2/7/18 - Pansy

For about the last week I have stopped "putting off" researching the overseas (UK) suppliers and their price lists.  Been a big job to get in the headspace, but I think I'm there now.  It all started when looking for some GWR style globe valves for the cab of Pansy, and also looking for the water gauges that are actually available.  I had drawn up the globe valves for the cab and managed to find them in a price list when I was looking up something else!

Some of these price lists are not that easy to decipher, and there's products hidden all over the place.  Particularly difficult sometimes to understand UK prototype locos and what stuff was on what loco, can't go down to the local tourist railway for a squiz!

Quite a good range in what Doug Hewson has, and have managed to find some stuff in the Polly "practical scale" catalogue.  Adam Cro of Cro Fittings is taking it to a new level...check out his website.

All the hashing and rehashing of pice lists has shown me that if I want a nice gauge glass that will look right in the cab I'm probably going to have to make it (unless I come across something I haven't yet seen!).  Not  that others don't sell the fittings, but the Boiler code compliance is one thing, and that you don't know how big these things are until you get them!  I've got a design up my sleeve for a nice gauge glass now...

In the last several years of learning curves I have become aware how difficult it has been to find readily-accessible information to give me a quick solution, or find an equivalent UK design.  I can search for hours and come up with a few things, but there's always that one time when you see someting you weren't looking for which would have been helpful last week!

Fortunately I have some Model Engineer resources which can be easily searched.  One of the typical things is remembering that I saw some technique or product somewhere, but I can't seem to remember exactly where it was!

Long overdue, but I have realised that I need a system to quickly recall and save information...a second "brain" where I can put all the loose ends.  I've had books and paper copies but they aren't easily edited.

I tend to avoid getting a program until I outgrow Excel or other Microsoft systems, as it's easy to be sold a product but the hard thing is customising it to do just what you want, once you know what it is you want!  So Excel with some hotlinks seems to work well for the time being.

I've managed to develop a quick lookup system in Excel to find me things like all the gauge glasses available, common sizes of tubes and fittings and threads, commnly available valves and what they look like (significant variations) and a host of other things like what size hex can you get off the shelf and where from if not in Australia.

I've got a filing system which lists

• Loco parts (cylinders, wheels, etc) and drawings I have of each
• Special tools and techniques.  Always handy to take photos and file away for later.
• Suppliers and who's got what, and what sizes are out there
• A Master spreadsheet of the commonly available sizes and combinations of things (say 3/16" pipe steam fitting has 5/16" x 32 threads, and the union nut for those will be 3/8" AF).  Makes a real easy job of making your own stuff if you can't get what you want.
• The Model Engineer designs (Who drew what and when - great resource to have). 
• Photos of models that I like (good inspiration)

Here are some common themes I've seen on different designs of 5" gauge engines.

• 3-5mm frames at about 4-1/8 to 4-1/4" apart (inside spacing).
• 3/4" silver steel or 4140 axle for the drivers, 5/8" for the other bogie wheels
• Pommy/fine scale wheels are usually 9/16" or 5/8" wide
• Plain bearing axle boxes are usually 1-1/4" wide and running height is with the axlebox 1/8" off the horn stay, and 3/16" from the top of the horn
• 16g (1.6mm) running boards with 18g (1.2mm) cab and tender platework
• Probably 1/16" rivets for platework, in some close spacing the exact number of rivets can look odd. Reduce the rivet size or less rivets for better effect.
• Mostly 3/16" plumbing for the steam stuff, and thereby having mostly 5/16" x 32 steam fittings
• Balls in check valves are usually the same diameter as the pipe.
• Minimum 5mm gauge glass (at least) which will be on 1/4" or 5/16" threads.  The dimension from the bottom nut to the centreline of the bush is a critical one for the 10% cover of the crownseet, I am yet to see a drawing with this dimension, but I believe it to be 1/2"
• Boiler tubes and flues for an average 5" barrel boiler I'd make is 1" flues, and 1/2" tube.  It is common to see the flues double the tube diameter.
• 3/8" radiant superheaters fit nicely up the 1" flues, 5/16" up 3/4" flues, and 1/4" in 5/8" flues.
• Non-stocked or expensive tube sizes in Australia of 5/16" or 7/16" means that the tube nests of some designs will have to be completely reworked.
• 3mm copper throughout the boiler to reduce the number of stays, stays being 1/4" solid copper rod
• 1/2" x 26" safety valves in most 5" gauge boilers.  If conventional valves don't relieve enough steam, go to pop valves.
• All the papers on blast pipes and chimey chokes for the sizes we deal with can be summed up in the steam has to get out without foofing around in the smokebox and back pressuring the cylinders!

 Happy steaming!

Nigel

Pansy

Finally have been able to get a blog app that seems to work on my new phone!

For the Pansy I have fitted some boiler securing grubscrews to the smokebox. And also made a short series blowdown valve which has a grubscrew in the valve. Makes much more clearance behind the side rod so that the valve can't unscrew and foul the
rod.

In looking at all the fittings and different suppliers I have come to find it is8 very difficult to cross reference across suppliers and find the standards and dimensions that the parts may be made to. So I have fortunately been able to find some old Model Engineer articles and LBSCs and Martin Evan's write ups. Plus all the goodies that come up on various forums.

My intention is to make some close scale fittings for the cab where we have that luxury.

Happy steaming!

Nigel

8/6/18 - Britannia

Some time was spent in the shed today looking at the cab and it's structure and where it is going to sit.  The Norman Spink drawings I have don't have a lot of dimensions so there are some approximations to do.

I've been making a "setting out" drawing of the heights of the buffer beam, and cab and some of the other things like the running boards made from the drawings I do have.  Thankfully there were some dimensions I could add up from the parts to work out where things will need to sit, and the brackets to support things.

Happy steamin!

Nigel

6/6-7/6/18 - Britannia

After the front buffer beam was fitted up, the rear drag beam was checked and it wasn't sitting level.
It was dsimantled and found to have some bolt holes that had been elongated and were preventing it sitting properly.  The paint was peeling.  So it was sand blasted and cleaned up and undercoated with etch primer and reassembled.  The slotted holes were driled out to clean them up and that has made it sit just fine.

The cab has some potential to look quite nicely detailed.  There's a bit of work in the platework to make it look right, fitting fasteners and doing some of the finish off jobs. The plate underneath that attaches to the drag beam will be checked out to see if we can use it.  The cab will be set up on the loco to see what has to be done to fix it up and establish where it sits.

Happy steaming!

Nigel

25/5 - 30/5/18 Britannia

The front steps and struts had to be reworked as they were out of square as well.  The spacer blocks that they attach onto were silver solderd to the brackets, and the struts were remade shorter.

Happy steaming!

Nigel

15/5 - 24/5/18 - Britannia

I've upgraded to a new phone and had a few issues uploading blogs. Hopefully the bugs are fixed! (No they are not, am uploading from my PC!)

I've been working out what's wrong with Britt's buffer beam, and it wasn't sitting horizontal according to the frame. After dismantling and sand blasting the repairs have been underway to fix the problems. The mounting holes in the frame and stretcher behind were way oversize and the clearance meant it could be clamped up anywhere.

The brackets behind the buffers were made out of square and so they were cut and silver soldered to fix them.

The running board mounting blocks were re made. Issues there meant the brackets were below flush with the top of the buffer beam.

The steps and struts are at all angles. Struts too long. Need to shorten/remake those.

Checked the stretcher behind buffer beam and the ends weren't square so it clamped it up on an angle. While in the mill taking a light skim off this the job grabbed and damaged it. So a new block of aluminium was sourced and a new one milled up...this time the corrections were made to it in the first instance.

The holes were drilled in the new stretcher, so that the 10BA screws for the brake piping are in through holes, a foresight incase they snapped off in a derailment.

The bits are in undercoat as we speak. Will upload some more tomorrow when it goes together.

Happy steamin!

Nigel

10/5 - 14/5/18 -Britannia

In the last couple of days I have made up some basic loco jacks for setting up the Britt (and similar locos). Made from coach bolts and some left over buffer plates. I can see a few improvements to them already but needed something infinitely adjustable.

The springing is not yet adjusted for the weight on the loco springs.

Happy steaming!

Nigel

8-9/5/18 - Princess Marina

A bit more work in the last couple of days machining up Princess Marina cylinders finishing off the LH cylinder boring and facing. I won't "bore" you with photos the same as the other day!

Happy steaming!

Nigel

4-7/5/18 - Princess Marina

Princess Marina cylinders are progressing with boring and facing. RH cylinder done and onto the left.

Also the Britannia has had a look in with the regulator rodding and pivot and linkages being researched and worked out.

Happy steaming!

Nigel

3/5/18 - Princess Marina

Some months back the owner of the Princess Marina I've been making bits for asked me to do the cylinders. These were ordered from the UK.

Today was spent measuring the extra metal and machining the faces and bores, the rearmost cover face and the bore being done square to each other.

I've decided to have a go at boring them out on the mill rather than setting them up on the lathe. The quill on the milling machine has a slow feedrate available and it seems to leave a reasonable finish on the first few cuts done.

Last time I used the boring head was boring out a big end bearing for a full size locomotive. The arbor and boring head are attached by a fine thread on the end of the arbor. The boring bar out the end of the boring head in that orientation (horizontal) requires the machine to run in reverse for the tip to cut. The intermittent cut on the big end bearing caused the head to unscrew from the arbor until I realised what was happening! Certainly made me jump at the time as the tool being out a long distance is very unwieldy and makes you think twice about where its going!

So some loctite bearing mount (610?) was used to lock up that thread so it wouldn't unscrew again. Didn't want to use threadlocker as its weaker than 610 and can still be undone with tools, happy to know some heat will get it undone. Wasn't happy to put a weld on it as it was brand new and may need another arbor in time to come!

Happy steaming!

Nigel

2/5/18 - Pansy

Well after a day of mucking around with the valve I have finally managed to get it to blow off with a 5psi pressure drop from open to close. It doesn't "jazz" or "buzz" much but definitely opens and closes without leakage which I am happy with. The final cup clearance was between .0155" and .0160". Any more than that and it starts to blow like a conventional valve, but any less and the pressure drop is abour 7psi.

A lighter gauge spring increased the pressure drop.

I had to make a checksheet for changes to critical dimensions as it was easy to lose track of what it was that had changed or what seemed to be a positive result. I ended up number stamping the end of the spindles.

I also played with the underside of the cup on one of the spindles as the shape I have to get 1mm engagement of cup and secondary seat flattens off the bottom of the cup and would be far more streamlined for any escaping gases. The measurement of reality against my CAD file meant the shape was a little different once the ball had bedded into the seat and cup.

I wondered if the shape of the underside being a recessed cup causes drag/eddying with the escaping air or steam, which I thought would push it open easier without increasing the cup diameter. Didn't seem to make much difference by just putting a groove on the underside. Might have a bit more of a think about that one.

I made a measuring cap to check the engagement of the cup and secondary seat while in situ which assists holding a digital caliper vertical.

Happy steaming!

Nigel

30/4 - 1/5/18 Pansy

Been still mucking about with the pop safety valve experimenting with different cup diameters. I took 1 thou cuts off the first one until it didn't pop anymore which was about .017" diameter clearance between the cup and the secondary seat.

I have another pop valve drawing which stipulates a .006" clearance but only has 4 exit holes at the top. I made some years ago which have .006" clearance and they seem to work OK.

Still getting ~10psi difference between lift and close and have a few more experiments tomorrow. I've changed the way I made the cup and spindle...both have threads but decided to do it into a blind hole rather than a through hole. The difference was the end of the stainless thread and brass being two different metals had shown that it was pushing the ball to one side once it bedded into the cup after a little bit of operation. The tangent point where the ball was sitting was on the end of the thread.  Also found the seat in the body needed a cleanup with the seating tool as the ball had made its own sweet spot on the square edge and flattened it a little.

Happy steaming!

Nigel

27/4/18 - Pansy

Today I finished off the safety valve adjusting tool and did some tests on the valve.

Found a better result with a short hose directly onto the compressor rather than through the long hose and regulator. The plunger was skimmed several times and I think I might have gone past the critical setting as it was popping nicely in all cases but the shut down pressure isn't less than 7-10psi lower than the blow off pressure.

I have some more spindles and plungers to trial.

Happy steaming!

Nigel

26/4/18 - Pansy

The test rig for the safety valve was made today from some plumbing pieces and a 3mm plate to clamp in the vise.

I made the nut and tail for the gauge as I didn't want to surrender one off this gauge and render it permanently assigned to the test rig. So while at it I beefed up the tiny little supply pipe so there's less chance of busting it off. The gauge sits on a nice ergonomic angle so no ungainly bending of the neck required for testing the valve :-)

Started making the adjusting spanner and then promptly lost the stainless pins I was making for it somewhere in the lathe! Wonderful to have such a clean machine but still couldn't find it! Ah well do it all again tomorrow!

Happy steaming!

Nigel

R class plates

A little while ago I had an order for a full sized R class number plate replica which I made from MDF, and also the North British Locomotive plate which is a copy the one belonging to R766. They were painted with enamels after sealing with primer and putty and look quite the part!

25/4/18 - Pansy

The safety valve body was drilled out and finished off with the seat tool.

The exterior body was profiled and tried with the shroud. Fits well. My final idea will have an O-ring to make the shroud a tighter fit on the valve so it doesn't come off so easily.

It was set up in the rotary table to mill the 1" hex on the base.

The plunger was made as are a couple of spares in the event too much is machined off the OD of the plunger. The aim is to achieve a minimal pressure drop between open and close and that is controlled by the diameter of the plunger.

The spindle and plunger were threaded a tight 3BA and silver soldered for security. The OD of the plunger was machined after soldering.

Happy steaming!

Nigel