A Robinson, in the " Making "

[Jo]

I made the comments because all your negative comments about castings can discourage beginners  You are not a beginner.

But using castings does take some of the enjoyment and satisfaction away from the process*,

Speak for yourself: fondling bar stock does nothing for me 

Cost only really comes into it on larger parts.

Until a beginner has a comprehensive set of bar stock then every bit will require them to buy yet another bit of bar stock  Kirt at Hemmingway is very good with his casting kits he provides all the bar stock so that beginners do not need to waste time and money buying stuff they probably won't need and will lay around rusting on their shelves 

Yes a few lucky people like me have over the years acquired material that now has that Alyn Foundry special protective coating but always make sure you know what you are getting. My steel stocks all came from the Apprentice School or Aero Space Companies 

Jo

[Jasonb]

That will be all the supplied imperial barstock and BA fasteners that most beginners don't understand will it

Just worked out the cost for the Vertical that I have just finished if I had to go out and buy every bit of material. Used M-Machine pricelist and going for 12"/300mm lengths of the smaller section and 1"/25mm of the larger section materials you could buy all materials for £80 plus VAT so say £100 and say another £20 for packs of 50 nuts in the sizes needed.
That's the same size as a Stuart No 7 and the 7A sells for £260. so allowing for the fact you will have more material that can be used on the next engine my 1/3rd the cost was about right. You also have easy to hold lengths and spare material if you muck up. How can that be a bad buy for a beginner?

[Alyn Foundry]

Good morning All.

Whilst I understand your point of view Jason I'm with Jo on " castings " being favoured over bar stock.

Perhaps it goes back to the many years of restoring vintage engines where missing parts were replaced with newly machined castings. I'm also a little lazy I found that making a pattern with all the shape was far easier than shaping a hard metal lump!

We're just waiting for it to stop raining long enough to get the " pot " on and do some casting of the Robinson " HA " base pattern.

Cheers Graham.

[Gas_mantle]

The subject of castings v barstock is an interesting one. I find that working from barstock worked out expensive to start with, when you are new to the hobby virtually every component you make needs the purchase of more barstock of a different size / material etc. As time goes on and you acquire a stockpile it becomes far cheaper. If I need to buy 2" of something I'll buy 12" and the rest is put aside for future projects so I have now reached the point where I can build most of the stuff I'm interested in at minimal cost.

To me the way forward seems to be buy a casting for the odd part that is difficult to make (or costly) but try to fabricate the rest. The Stuart no4 replica I'm working on is going to be primarily a barstock engine (I bought the trunk guide for £1.40) but in the case of the cylinder / valve chest when I tried to buy the cast iron stock I found it as expensive as buying a casting so I did the common sense thing and bought a casting.

I reckon all in I can build a Stuart no4 lookalike for £80, it's not going to be perfect and it won't sell for the kind of money a real one does but at 20% of the cost I should have a reasonable engine and the satisfaction of saying I built it (or most of it)

[Jasonb]

We're just waiting for it to stop raining long enough to get the " pot " on and do some casting of the Robinson " HA " base pattern.

I take it that as you sound like you are casting at home that this will be the Aluminium pattern that will then go off to the iron Foundry? Would be interested to see a couple of photos of your casting set up.

Agree with you that the larger full size and big model parts are often better done with castings particularly if you have a local Foundry that will do one offs. But if you only want a small part for a model having to spend a day driving to and back from a foundry twice plus petrol costs will soon make cutting from the solid seem attractive

[Jo]

How can that be a bad buy for a beginner?

And they will have to buy lots of other tools over and above the lathe that most people start with when they build model engines, tools that most of us slowly buy over many years like silver soldering equipment which requires even more skills that the beginner must learn before they can achieve their first engine   


Most of the model engineering companies who provide us with, amongst other things, excellent castings sets are making very little in the way of profits: use them or loose them. Encouraging scratch building from the new customer market will ensure we loose them earlier   


Jo

[Jasonb]

I'm not going to disrupt Graham's thread any more but if you want to move these posts to a new thread it would be worth continuing

[Alyn Foundry]

No problem, it's a lively debate....

In essence that's what this thread was all about. Showing how a model starts from either an idea or the real thing. The pattern making, casting and machining until a finished product.

Anyone can make patterns and almost anyone can make their own Aluminium castings too.

My first casting was actually in Brass believe it or not. I used a converted " Rayburn " fire, the one with the segmented glass front door. Used coke and air and a small 10 Lb " Morganite " crucible. I did everything right until I poured the mould. Disaster, just as the sprue was filling the boxes parted and I had what I learned later, in good old foundry parlance, a " Pisser " !! Yes you guessed it, I hadn't put any weights on the top box. The displacement of molten Brass is far greater than that of damp sand!

That event was 40 years ago now....

Cheers Graham.

[Jasonb]

Just hope you did not scorch the front room carpet too much.

Well if you don't mind then I'll comment on Jo's last post.

I don't see why anyone making one of my 24mm bore engines would need to buy much more in the way of tools and tooling over and above the lathe. Granted mills etc will make the job easier but any of them could be done on just the late, if I can make a Minnie with just the lathe when I was still very much a beginner then I don't see why anyone else could not manage one of these simpler engines with just a lathe.

As for silver soldering a couple don't need any and those that do use it could have those parts made in other ways with either simple screw together construction or as the likes of Ramon have shown a steam engine cylinder can be stuck together with JBWeld and hapily be steamed.

Yes if the suppliers don't move with the times they could disappear particularly with the growing number of people with CNC and 3D printing in their home workshops which makes it even easier for the scratch builder to make their own patterns or machine complex parts from solid. But at least the models being made will cover many new and varied subjects rather than just banging out the same 100year old designs again and again.

[Alyn Foundry]

Hmmm....

Well this Robinson in the " Making " will definitely be a 100 year old design!!   

[Jo]

Please take note Graham: Jason clearly doesn't want those casting sets he is trying to buy from you Just like that totally unnecessary Robinson X type cylinder, flywheel and the base that you forced him to buy so that he didn't have to make them out of bar stock   

If you think about it the heretic has brought more castings than I have this year  He says one thing... and does another 

Jo

[Jasonb]

Not really Jo just showing that engines can be made either way and that castings don't have to limit your choice of subject. I'm happy to build both ways or mix the two to get the results I personally want, did not know I could not share my views with others.

The way some people go on about castings the beginner could be lead to believe its the only way.

I've only bought one and a half casting set this year but completed two scratchbuilds with a third underway. Also I don't have any where near the amount you have stashed away.

[Gas_mantle]

Funnily enough in the last few minutes, I've just bought a 10v casting set on ebay - I didn't really need it but it's still sealed in the plastic and has the Andrew Smith book included - It was a bargain I couldn't resist :-)

I now have 3 verticals to build 

[Jasonb]

If you can get them at a good price then why not. That's probably why Jo has bought less than me this year as she has very bought all that Eric had to sell at a very good price and does not want to spend more on anything else, not that there is much left that she has not already got

[zeeprogrammer]

Apologies if I shouldn't be throwing in my two cents...

Regardless of some people's opinion...I'm still a newbie. I'm currently doing what I consider my 1st casting kit.
It's been much more of a challenge than my other bar-stock engines.
Primarily because it adds challenges to holding parts and determining reference points.
Not to mention (as a newbie) the increase in anxiety knowing that if you screw up...you're buying another casting part (if you can) rather than a bit of bar.

For me, this isn't a discussion about 'one over the other' but 'what is appropriate/desirable for the model and builder'.

Many experienced people (and not so experienced as myself) forget what they didn't know.

My 1st engine was indeed a casting. But a very simple model that came with a 'how-to' video. Even so, I ended up purchasing two more flywheels. (Actually two whole kits because it wasn't just the flywheels I screwed up.)

I remember when I first started this hobby. It's a lot of learning. The machines, tools, methods, finding center, setting cutters, feeds/speeds, and on and on.
At the time I thought 'drill a hole' was it. Not spot, drill, ream. Tapping threads? Who knew there were up to 3 taps to use?

Having said that...when I was young, it was casting kits that caught my attention and ignited the flame.
It burned for some 45 years before I was able to jump in. Had I started with a real casting kit...I think I would have failed and the flame be extinguished.