5"g Simplex steam loco build (hopefully)

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Dec 12, 2012
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Looking for my next project,needs to be sustantial.I now have more tooling than i have ever had and there is not much more to make so need to start using it.I have decided to start on the 5"simplex loco even if it never gets finished.The main reasons are i have the drawings,castings etc are readily available and its much simpler than the HEILAN LASSIE i got 75% complete
The last loco was in the early 2000s,i had 2 Myford lathes,vertical slide and drill
press etc.So there was lots of sawing and filing.I was also working long hours
Now i have a mill,lathes etc,and DRO on the mill for accurate drilling/boring etc And a lot more time on my hands
Downside is that bright bar in flats and angles and imperial is not readily available so much of it will have to be metric HRS,Will be working a mix of metric/imperial to suit.Where possible i will use hs cap screws,hex hds will have
to be purchased in BA . Will chart progress and compare the 2 builds from 2000
in UK to 2017 in Oz,Will start with the frames,stretchers and buffer beams so
can build up something to look at.Any advice where to get castings and fixings etc here in Oz
Can't help with where to buy castings. But I will be following this build. I like the 5" gauge locos, easy to transport (for standard gauge, narrow gauge is a bit more bulky), and enough clout to pull you around the tracks with a party of friends :)

I also want to build a 5" steam loco but not just yet. Need some more experience first. If you lived over here I could shoot you straight to laser cut frames castings and other parts that'll get you going fairly quick.
Thanks Steve,i checked out the link and came across a thread on this forum
Made a pair of frames as per std,i must say its much easier with a mill
Cant wait to do some acurate drilling with the mill and DRO 01 frame.jpg

02 frame.jpg
Lots of drilling ahead Baz, but I'm sure you already know that. I'm interested to see how it turns out. A coat of primer is too, so many models that I've seen, develop surface rust due to the time it takes to complete them.
A light coat of primer keeps it clean and aids marking out rather than blueing
Also a light coat on say angle cleats before they are rivited to the buffer/drag beams stopp rust on closed mating surfaces.Lots of drilling but all i had for HEILAN LASSIE was mark out and a cheap bench drill.With the mill and dro i should at least get a straight line and equal centres for the rivits
There is also a book about building Simplex. "Simplex 0-6-0 Tank" "Simple Freelance Steam Locomotive" by Martin Evans published by Model & Allied Publications Argus Books Limited in 1977. ISBN 0 85242 796 4. We have a few in the club. There was also a Super Simplex.

Some club members in the club dont buy casting or perhaps just buy the wheels and make the rest from solid or fabrications. Buy continuous cast iron lump and cut the cylinders from that


A few more hours marking out and drilling the frames.Cleats,beams and stretchers made,ready to start assembly.3 days to get to this stage
my first one took a month.Boy do i hate too much hacksawing and filing
Its great to mill the stretchers knowing they are spot on square and to size03 frame.jpg

04 frame.jpg

frame 05.jpg
Made the frames,stretchers and beams and fully assembled
Had enough rivits from many years ago but only temp fixings
until i can collate a bolt list.Basically everything done thats on the first drawing
Then i made the mistake of studying the rest of the drgs. Frightening.
Starting to worry about the boiler,like a fool. Just concentrate on a bit at time
and dont worry about the rest.Its good to start with the easy bits and build up
I have orsered a copy of Martins book and wlii order some fixings, the wheels
and the axle boxes next.I am enjoying it even if it never gets finished
All i can sy is the mill and dro sure make things easierframe 06.jpg

frame 07.JPG
Check out Mr Crispin's channel. He 'can't afford' the castings, and is machining everything from solid.
I wouldn't be looking too far ahead, why worry about it now when in about a week the boiler will be upon you lol. Your working fast I bet the machines are helping with that, well just a little any how. What you need to be thinking about is paint schemes, I'll stop rambling now and let you get on with the axle bearing blocks
All the work on the frames etc was milling and drilling so i decided to do
some turning.Chose to do the buffers,out of sequence but i had the matl
to hand and they can be made and fitted to add a bit of bling at this early
stage.The drg shows a 3/8" threaded spigot thru the beam with a large nut
holding it on.Apart from being out of scale and looking ugly its doing nothing
the 4 fixings from the front hold it on,so i turned a plain spigot shorter than shown and looks wise is much improved.Any body out there made this model
i wonder how many people just blindly follow the drawings?
I have ordered the book and the wheels.Now starting on the horns.2 versions are drawn.The castings in bronze cost $150 so will make the simple fabricated
ones for free.The axle boxes cost $150 so i bought a foot of 11/4" sq brass
Also got matl for axles etc.Next job is to make the axles,bearing and wheels etc
before i start on the connecting rodsbuffer 01.JPG

buffer 02.jpg

buffer 03.jpg

buffer 04.jpg
I spent a few days fabricating the horn blocks.Easy stuff but an incorrect dim on the drg means i will have to make new top plates.No problem but i should have seen it..Made the axle boxes from brass.Axles were bright mild steel
about 1.5 thou under 3/4" but i dont have a reamer so i bored out to suit
in the lathe.Everything dropped together but the horns and axle boxes will
need fitting.Need a little slop of they bind up when running on curves etc
Did some more drilling and tapping to fully fit all screws and replace the temp
ones.Not bad for 2 weeks work but this is all the easy bits.Wheels are orderedaxle 01.jpg

axle 02.jpg

axle 03.jpg

axle 04.jpg

axle 05.jpg
Before it starts to get too heavy i wanted to make a stand to hold stable and a better height.Lots of thoughts on timber etc going thru my head when just
before i fell asleep bingo.Local steel shop sell corner connectors so boght
some 1" sq rhs and 1 hr later.Very pleased.Milled 4 slots 10mm wide in the tube then fitted the plastic end caps before running a 6mm cutter thru
Corners of the 5mm buffers sit nice and snug on the plastic so no damage
if it ever gets to the finish painted stage.Finishe the horns,axle boxes etc
Now on the the pump eccentric and strap while i wait for the wheels to arrivestand 01.jpg

stand 02.jpg

stand 03.jpg

stand 04.jpg

stand 05.jpg
A very handy stand :)

Maybe worth thinking ahead, I've seen a stand very similar to yours that has a rotating feature, to allow access to the underside, the loco simply bolts to a plate via the buffers, with locating tabs that are welded to the plate, and turned to fit inside the buffers. This plate is then bolted to the frame with a catch pin (bolt) that secures the loco in any position you need, (once the holes are drilled).

Just make the stand 1" higher than the center line of the buffers to the top of the roof, then when your further down the build you won't have to keep flipping the loco. Just unbolt the plates and turn to whichever position is needed, rebolt job done, is great for maintenance when the loco is in service.

I do like the simple stand though. Effective at supporting the loco with very little outlay. Thumbs up!!
Full size BMC Minis were actually rotated to put the engines/gearboxes and subframes in.

I had a set of Car Rollers which were J's and bolted to the wheels of my Morris Minor. They were pretty tough and would hold a 3.5litre Jaguar.

Quite interesting being able to shove a car over unaided to weld and not having the oxy sparks ending up in one's ears!


Good idea Norm will look at incorporating the spin feature in near future
when unit starts to get heavy.Its adequate for now.Talking about spinning the MIni, i did a thread very early on about duilding a 40ft steel hull boat.Also weldedpieces of 6'Dia tube on each end so the lower hull section could be
spun the right way up after fully welding the hull etc.Should have rememberedhull 03.jpg

hull 06.jpg

river 02.jpg
From bitter experience i will avoid doing all the shaping of the conrods first
only to find i have cocked up on the knuckle joint or wheel centres
This time i started with oversize bar,drilled and reamed for the driving axle
made and fitted the T & G knuckle joint,made and fitted 3 no stub axles
then using the the centre hole as a datum drilled and reamed for the leading
and trailing axles.The did a fitting directly to the stub axles.Only when i was
confident that all was correct did i start shaping the rods.Again i was very pleased how easy it was with Mill and DRO over hacksaw and file /drill etc
2 days using various setups to finish mill to size and shape.Then i made the
centre bushes and fitted.Turned down the middle stub axle and ensured a good
fit .A little tight but if it goes on it cant be far away.Better to test fit direct to
axles,if you fit to the wheels then rotate to give a good fit but then you have a tight spot which is difficult to get rid of.A final wipe of the axle boxes on the beast side should give me a perfect fitconrod 01.jpg

conrod 02.jpg

conrod 03.jpg

conrod 04.jpg

conrod 05.jpg

conrod 06.jpg

conrod 07.jpg

conrod 08.jpg

conrod 09.JPG

conrod 10.JPG
Very nicely done I can see why you left them oversized now, I thought it was just to sidestep to the next step, now I see that it was all part of the process. :)

I take it you had some issues with burrs on the rear left axle bearing?
No issue with burrs. When i did Heilan Lassie i spent a long time shaping
and polishing the rods only to cock up on the wheel centres on one
That was down to marking out and drilling and using a vertical slide
Doing it this way took longer but getting the knuckle joint on th the drive axle correct,then working back to get the wheel centres correct by fitting direct to the stub axles,got the hard part done.Thankfully i also took my time shaping the rods and did not cock up on them.Waiting for the wheels to arrive then i can finish the rest of the bushes and fit to the pins

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