Here is a list of all the postings Luker has made in our forums. Click on a thread name to jump to the thread.
|Thread: Ballaarat construction series|
I think you may find similar castings, any inside frame Stephenson 5g model with similar bore and stroke could probably be modified. The cylinder castings and cylinders are shown below. The fancy cutouts around the steam ports are only to improve the castability, and aren't necessary (besides these are at the bottom and on the large loco this was covered in cladding).
Thanks guys; Jon I like the wiki page!
Jason; there should be enough dimensions to make patterns. If any are missing it wasn't intentional. I have no doubt that there is no casting I can come up with that you can't fabricate! But for the average builder or even the beginner I don't think any of the parts will pose much of a problem (to fabricate). The cylinders will require a decent torch, and some of the detail can be left out to simplify.
With the price of hacksaw blades and files I think the laser cutting comes out cheaper, I’ve started cutting up my old band saw blades to make hacksaw blades…
I can’t help with exact costing because most of the materials came from scrap or left over stock from one of my previous builds. The design uses common bar stock and metric fasteners available from pretty much anywhere. The main items were as follows:
Laser cutting $138 (this includes the frames, linkages and boiler - laser cut and rolled)
Castings from scrap
All boiler fittings machined from risers or non-ferrous hex bar, depending on the position
All copper steam lines from refrigeration tubing
Paint - 2k automotive paint
I used a model engineering trade gauge someone gave me but this will be replaced as soon as I make a batch of gauges for my current loco.
And a video of the little one going around our little track...
Hi everyone, here's a video of the real Ballaarat resting in state...
Thanks to Jacquie for sending it through!
Hi All, the first installment of the little Ballaarat is in the current issue. I'm quite excited about sharing this build! I hope everybody enjoys the series. Here's a small animation of the design. I removed the back panel to make the backhead more visible.
|Thread: advice old British motorcycle|
Any late 50's twin cylinder. Parts are interchangeable for the most part, kick start easy and have that lovely sound that only a twin can produce.
My Ariel 650 has BSA heads and rockers…
|Thread: Surface finish when turning.|
Hi Robin, I normally don't get involved with online prognosis because there could be any number of reasons for what you getting there, but in this case I feel your pain! I had something similar when I bought my lathe and it was actually a design issue on the machine itself, and very specific to the machine, so may not be applicable to you. Most of the modern Eastern import gear head lathes sold with CQ numbers suffer from this. If you drop us a picture of your lathe and makers code, and its the same as mine I'll take some pictures with a short write-up and post...
|Thread: What's in a Word? ME 4667 Postbag|
I also thought the letters were a little harsh, with the author doing a good job in keeping the article and topic simple for most people to grasp the underlying principles. Seems people are very quick to complain about errors in drawings or poorly designed models but modern design methods like parameterization and linked 3D geometries don't find favour (at least if these letters are to be taken as the norm). If a designer uses all these CAD methods then models can be virtually assembled, the linkages tested and dynamically checked and drawings produced to a much better (building) standard than in the good old days of drawing boards. I for one enjoyed that article and found it informative, and make extensive use of parameterization, linked geometries, dynamic simulations, FEA and all other manners of jargon that you hear politicians say on a daily basis. (for Howard )
|Thread: drilling a bearing ball|
I had to replace a lost probe point a few years back. Normal inner ball from a std bearing was annealed similar to how Jason suggested; the only difference, it was heated on some dry sand (with a little dishwashing liq) and pushed in with a wooden dowel. Was drilled and tapped using HSS. Any concentricity issues are inherently solved by the small centre drill breaking, but even with a wobbler type probe if you centre it with your finger on the ball all will be good...
|Thread: What is your favourite "unusual tool that you find useful" ?|
Press stick; used for center finding and assembly aid. Also good to stick charts to workshop walls..
Looking forward to this thread!
Here's mine: Its a V-block set that can be used as an angle as well...
|Thread: Casting copper ?|
I would push a bar of the correct diameter in some sand and cast as normal. Copper tends to react with oxides so casting into any pipe needs to be done with the pipe very clean, and don't stand over the pipe when casting. Once poured, cover the top of the copper with coal dust, otherwise it "boils". Sand mix:
10% bentonite (from beauty shop-face mask)
5%starch (cake flour)
With such a simple mould you'll probably get away with 3% water and 10% starch (rem sand)
I'm surprised copper isn't cast more often, a number of the older models had copper chimney stacks...
|Thread: Ballaarat construction series|
Yep this little loco is loads of fun on the track, and easy to drive (no pesky roof or cut-outs to take skin off). She takes two large adults without slipping or complaining (haven’t connected another drive cart to see how many people she could carry). She has a constant lead valve gear so you just slip the reverser in full forward and you can forget about it until you parked in the station again. I haven’t found the valve gear to be lumpy (suppose that’s the benefits of dynamic simulations) and I can get my fingers between the cylinders for maintenance etc. I actually blew out one of the valve chest gaskets when I was (abusively) testing the loco and it was no issue to take the cover off and replace the gasket (just baking paper, no sealant) on the loco. I had forgotten to tighten two nuts and she still steamed for the rest of the day. Incidentally when I test a loco I do a proper job to make sure the design is sound.
I like the analysis of the gents in the manufacturing yard picture! Seems like, even in those days the person that’ll do most of the work is furthest from the loco.
Na, I just liked the look of that low pitched boiler and the odd valve gear. I actually didn’t know of the connection to Pretoria…
I call this my COVID loco; it was designed and built in the first 9 months of 2020 when we had a very restrictive lockdown.
Hi everyone. Here’s a little sneak peak of my next construction series… hopefully not much longer before it gets published.
An exceptional video of the Ballaarat by Anthony Dawson (thanks to him for permission to embed it here)…
|Thread: Wahya construction series|
Thanks Nigel. Everybody at our club likes the wooden cab, it's a little sad that the roof and back panels are removed for driving. But she looks good on the display stand.
The water valve handles look like that because the builders used a valve that lifted instead of the normal turn-taper valve. I kept the valve simple in the model but tried to capture some of this detail.
One highlight of the American type loco is the stability on the track with the compensated suspension over the trucks(bogies) and driving wheels. She really does glide; even on our rough track.
The final installment of the Wahya series is in the current ME; finishing off the tender fittings. I hope the readers enjoyed the write-up as much as I enjoyed sharing the design and build. To close off the build I thought I would post some pictures of the ride-on seat (sporting fittings for the shovel etc. and hand break) and the full loco at our track. Thanks to everyone who sent comments both through ME and this forum, much appreciated!
|Thread: facilitas 3.5 gauge|
Yep I agree, and it should be a decent hauler. Its going to be an interesting build, I'm looking forward to see the loco take form.
I had a look at this loco today, its a 3.5g 4-6-2 with Facilitas on the side of the engine on the GA. As Peter said the drawings are old with no sheet descriptions etc. It looks very similar to the picture you posted.
The frame, motion work, wheels and cylinders etc. have been completed for the most part and the boiler looks like it’s complete but not fitted. A couple of interesting points that had me stumped...
I’m curious to know if anyone has seen this loco in steam. Looking very quickly at the proportions and drawings it looks like it will be one hell of a steamer…
Ps, Peter I hope you don’t mind me adding this in…
|Thread: SMOOTHING 3D PRINTS|
I honestly don’t know if acetone works on other printer filaments, never tried. In my humble opinion and from my personal experiments fume polishing has less effect on the vertical edges of a print which is where it’s needed most.
The spray is not for porosity it’s to seal the print. If you have hundreds of lines thermally joined there might be places where they don’t join properly. When dipping the pattern the slurry fills these areas causing poor surface quality. If you’re using printed patters for investment moulding the foundry should do a vacuum test. An easy way for you to check is to submerge the pattern in some warm water and check for any bubbles as the air inside the pattern expands.
I think you misunderstand Jason and I RE the flexible (silicone) moulds. The end result is a wax pattern you give to the foundry. A positive is printed using 3D printing (or a sample), the silicone is poured around this (a negative mould), and finally you can pour wax into this mould. I unfortunately don’t have pictures of this exactly but I have used this process to make badges for one of my vintages, the underlining concept should be clear from the pics… Incidentally you don’t need to buy potting silicone, calking silicone with corn starch mixed in and a little terps as thinning agent will also work if you want to experiment a little. Tricks for mixing and releasing agents are in the article…
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