Impetus Hunslet 15"

[Mike Paterson]

After the Sharman P4 wheel set arrived from Phoenix Precision i could make a start.

First job was to clean up the backs of the wheels. This entailed removing the molding pips and giving the back of the wheel a rub on some 600 grit wet and dry glued to a piece of plywood. Next the axle holes were slightly countersink using a handheld rose type countersink.

One this was done it was possible to cut the " cut it yourself" axles to length. I am fortunate in owning a Toyo ML210 lathe. I am not proficient in its use, but can use it safely and on occasion pieces emerge from it roughly to dimension. First job was to turn down some brass rod to make a long axle that was a sliding fit. I could of used a bamboo skewer but I want to be more competent with the lathe. With this made, it was possible to measure the required axle length using a Vernier caliper.

axle length setup.jpg

Axle length measurement set up.
I really must get out the tripod so i can close up the aperture on the camera to get a better depth of field.

As others have said, the hardest part is getting started. so here we go.

[davebradwell]

Don't know why you want the brass axle - just put wheels against gauge and measure over bosses. It's worth adding a little (0.1-0.2) to the length just to be sure that the axles aren't short, which looks bad. Don't forget to represent the "centre" in the end and this also removes any turning pip if your tool isn't exactly at centre height. Also break the sharp corner and remove any burrs where you m/c the end to avoid it cutting a larger hole through the wheel.

You might also measure distance between wheel bosses and width over axleboxes to work out spacers required, allowing for endfloat of course.

DaveB

[Terry Bendall]

but I want to be more competent with the lathe.

The articles on using machine tools that appeared in Scalefour News between December 2008 and June 2010 mat be useful.

Terry Bendall

[Jeremy Suter]

Don't know why you want the brass axle - just put wheels against gauge and measure over bosses.

Not a bad Idea though. If you feel the need for your own piece of mind on the accuracy of measuring, it is a third hand and will keep them parallel for measuring.
I had to make some new axles a short while ago and will write if up later.

[Mike Paterson]

Terry, thank you for the reminder about your articles. I have downloaded them and started to read through them. I feel a fly cutter maybe handy for future projects.

So firstly a bit of history:

The Hunslet 15” 0-6-0 was produced from 1923 to 1945. 27 were built in total. They all were similar in appearance with the difference being mainly cosmetic but some had larger 23 inch buffers and the sand boxes were in different positions. They all had 3' 7” 10 spoke wheels and were found at several collieries with 6 at Mersey docks. Not sure how one ended up in the west country, but hopefully it will be seen running on Watermouth pulling a few wagons up from the harbor.

The kit will be built as it was purchased. This includes compensation using the horn blocks provided. A rummage in the stash has found another HL gearbox. This one includes the removable axle gearwheel.

The running plate was started first. The two layer buffer beams were sweated together using a couple of bamboo skewers jammed through the buffer holes into a lump of insulation board to keep the layers aligned. With the front buffer beam attached the two valance strips were soldered into place. The etching process produces a cusp. This often needs to be removed but in this case it came in handy. It actually located into the half etched slot on the underside of the running plate. These strips were held in place with a couple of pieces of 12mm square wood with a razor saw cut in them. Next the rear buffer beam could be soldered into place. Once again the bamboo skewers were used to hold the running plate still whilst the buffer beam was soldered into its location.

valance tool 1.JPG

running plate and gbox.jpg

The running plate can now be used to determine which gearbox and motor will be fitted. At this stage it looked like the motor/gearbox combination I had would not fit where i wanted it. A HL gearbox and motor was then ordered.

[Mike Paterson]

New gearbox built and it looks like it will fit into the firebox. Cab sides and front assembled onto the running plate with the firebox fitted loosely to check gearbox fit. Brass buffer housings soldered into place.

body with cab sides.JPG

I always use lead solder because I have a pile of the stuff as a result of my ex employer going all lead free. Currently using RS 0.5 mm dia 180 degree resin cored. I have used this sort of solder since my days as an avionics technician.

Next to be built was the saddle tank frame. The frame when checked against the wrapper was too big. On checking the instructions again I missed reference to a small sketch on the assembly drawing that showed that the frame needed trimming down slightly. Once the tank frame was dismantled and the parts slimmed down to the correct dimensions the wrapper fitted with a bit of wriggle room.

saddle frame 1.JPG

Chassis should be be next

[down_under]

The running plate was started first. The two layer buffer beams were sweated together using a couple of bamboo skewers jammed through the buffer holes into a lump of insulation board to keep the layers aligned. With the front buffer beam attached the two valance strips were soldered into place. The etching process produces a cusp. This often needs to be removed but in this case it came in handy. It actually located into the half etched slot on the underside of the running plate. These strips were held in place with a couple of pieces of 12mm square wood with a razor saw cut in them. Next the rear buffer beam could be soldered into place. Once again the bamboo skewers were used to hold the running plate still whilst the buffer beam was soldered into its location.
valance tool 1.JPG

running plate and gbox.jpg
The running plate can now be used to determine which gearbox and motor will be fitted. At this stage it looked like the motor/gearbox combination I had would not fit where i wanted it. A HL gearbox and motor was then ordered.

Thanks for those pictures Mike - never thought of using a block of wood like that to hold the thin valance strips. I just tried it on a Judith Edge 14" Hunslet and it worked a treat.

James

[Terry Bendall]

never thought of using a block of wood like that to hold the thin valance strips.

This is a dodge that I use quite often and I keep a box of various sizes of wood on the bench for different jobs. They get used quite frequently.

Terry Bendall

[Mike Paterson]

The chassis has to wait for a while whilst the saddle tank is completed. My last saddle tank was my first one. After annealing, rolling with brass rods on mouse mats, yellow pages, racing post etc. I still could not get it to a decent shape so after yet more annealing I finally beat it into shape using a rolling pin as a former and held in place with 4 x clamp hose worm drive aka Jubilee clips. So after that effort I bought a GW models rolling mill. That had been waiting for its day of glory in my attic. The Hunslet tank wrapper was formed in about 5 minutes. It took longer to unpack the roller and attach it to my vice. Brilliant piece of kit.

completed tank.JPG

The tank wrapper was soldered on, this was accompanied by a visit from Mr Cockup. 50:50 chance of fitting it the wrong way around and i managed to do it. So a few new holes later and I think I have rescued it. For some reason, lost in the mist of time, I must have robbed the kit of a few hand rail knobs as i was a few short.
As you can see the tank wrapper has half etched lines on the underside. I hope that once it is primed and painted these will not be too obvious. Once the tank is mainly finished I will go onto the chassis.

[steve howe]

So after that effort I bought a GW models rolling mill. That had been waiting for its day of glory in my attic. The Hunslet tank wrapper was formed in about 5 minutes. It took longer to unpack the roller and attach it to my vice. Brilliant piece of kit.
completed tank.JPG

I might be borrowing that Mike!

Steve

[Daddyman]

That looks very good indeed. I don't fancy your chances of covering the ridges with paint, but you will be able to sand them out easily - assuming the wrapper is more than 5 thou, given that it has bending lines etched in. Just be careful to get even pressure - a sanding stick made from 240 grit Halford's paper superglued to a length of PCB or even wood would be better than the commercially available sanding strips, which are too flexible (at least the ones I've come across).

[Paul Willis]

So after that effort I bought a GW models rolling mill. That had been waiting for its day of glory in my attic. The Hunslet tank wrapper was formed in about 5 minutes. It took longer to unpack the roller and attach it to my vice. Brilliant piece of kit.
completed tank.JPG

I might be borrowing that Mike!

I do keep telling anyone that would listen that the time to stock up on GW tools is now... I don't use them often, but when I do, they do just what I expect them to do.

George Watts won't be churning these out in his shed for ever. I already have a backup wheel press, just in case I lose my first!

Best,
Paul

[Mike Paterson]

Over the last few months I have not been totally idle on the Hunslet 15". I had planned to build up the chassis and hopefully have it running however things did not work out that way. The chassis and gearbox were built. The motor fits into the Firebox which was a good result. The wheels were mounted on the Axles using the GW models Quartering jig, most wheels went on fairly square but one was very wobbly but that will wait until later. I could not get the driven axle to rotate reliably and it took a considerable time to work out what the problem was. Whilst I was working out the fit of the gearbox/motor assembly I decided not to fix the gearbox extender to the gearbox sides. By now several of you are well ahead of me and know what the problem was. The gears were intermittently meshing to lock up the gearbox. With that solved I can go back to the chassis in the future.

The remaining parts of the body were assembled without much drama. The smokebox wrapper was annealed and formed to shape by bending it using a piece of round bar. With that in place the boiler tube can be cut to size. I aim to keep the boiler and saddle tank separate as this makes painting easier.

The Saddle tank fittings (dome and tank filler) were fitted using epoxy resin after final fitting to suit. A nut is soldered underneath to allow it to be fitted to the boiler.

Once I was happy with the overall fit the whole body was cleaned using a pumice based cleaner (Astonish brand) degreased with dilute green detergent and finally a wash with Cillit bang Lime and grime. The body was sprayed with Upol 8 primer. This does appear to adhere well. Grey primer should be OK underneath the planned green paint.

body on chassis.JPG

On reading Paul's comment Re: GW Models I purchased a spare Quartering jig and a wheel puller which hopefully I can use to remove my wobbly wheels. It looks like that was a good thing to do as I was reading the Mr. Watts has hung up his files.

[Philip Hall]

Re GW Models: where did you read this? I spoke to George Watts just now and he is definitely not retiring. Working more slowly now but still has a full order book.

I did google GW and came up with a reference to a range that Games Workshop were retiring. No idea what they this refers to but maybe that's where it came from?

Philip

[Mike Paterson]

I heard it on that reliable source RMweb . More than happy to be corrected with reliable info. This happened the same time I received a parcel from him with several items on his list/receipt listing them as unavailable including something i was looking for, so the rmweb post sounded about right.

[Philip Hall]

Thanks Mike. If you are on RMWeb are you able to correct the misinformation please? I know George would be grateful. Thanks.

Philip

[Mike Paterson]

Philip, sorry to say I am not on rmweb, just a lurker.