ESE's works engine tuner

[Flettner]

My school's older than yours.

And yeah, you can print wax, jewellery industry has been doing it for a while. Amazing resolution too.

Don't know what toys Frits has. But quite a while ago I got involved on the outskirts of the development of printing metal powders. It was just market-ready then, with a limited range of tool steels and Ti. The one major advantage, of course is the ability to make hollow shapes impossible for any other process. I believe Volvo make pump impellors using the system, but I'd be surprised if they've ironed the wrinkles so far yet as to allow printing 7000 series aluminium.

Hideously expensive, of course. But then, so was printing ink when I were a nipper...

Just that I got cornered at the last Emex show by several 3D printer salesmen trying to sell me "the next big thing". What use is it I would ask? Next I would be show all these plastic trinkets, a plastic bearing no less. What use is it I would say again? You could show your customers a prototype of your production model ( a bearing ). I said, I would just show them a real bearing, you know, one that they could use. What use is it showing customers somthing that we couldn't produce on the CNC ( the same machine we would use for production ). What use is a junk prototype of a part we would make in the CNC anyway, and actaly use.
I have customers now comming to me to make parts that they have tried to make on their 3D printer, most wondering why they bought the useless things in the first place. And did I mention how slow they are!
Hey thats just me.

[Ocean1]

I have customers now comming to me to make parts that they have tried to make on their 3D printer, most wondering why they bought the useless things in the first place.

Meh, lots of guys can use the right tool for the job...

[cotswold]

Just out of interest here a Dyno pull done on my RS125 Aprilia, it's stock bar the Gianelli pipe.
Is this the why the foul strokes boys won't let us have liquid cooled 125's ?

[Drew]

Isn't TZ getting that out of an old air cooled bike with a 24mm carb?

[cotswold]

Isn't TZ getting that out of an old air cooled bike with a 24mm carb?

He sure is but only after years of effort, can you imagine where the line would stop if he took to one that has 30 from stock
rather than 12?

[TZ350]

Just out of interest here a Dyno pull done on my RS125 Aprilia, it's stock bar the Gianelli pipe.

I have one of those RS125 cylinders, if the water cooled to air cooled conversion works out I might give the Aprilia cylinder with a TF bottom end a go too.

Isn't TZ getting that out of an old air cooled bike with a 24mm carb?

Best of 31 hp, but not all that reliably, although that could be about to change.

[Frits Overmars]

...I hate those 3D printers but perhaps there is a use for them in printing wax? Can they print wax? Perhaps I could CNC 3D machine a pattern direct, out of wax? No, just better off machining a steel die for shell sand. No, perhaps better off machining a male in carbon and spark eroding into steel. Cover the steel mould in ceramic paint and you have a die cast setup, pour straight in the steel die with hard sand cores locked inside, that way we could make lots and lots of them real quick!

Yes, they can print wax. They can even print sand:

Notice the cooling ducts inside the transfer curvatures? Try making that in a steel die (come to think of it: I wouldn't put it past you...)

Actually just get one of those 3D metal printers Frits has.

I wish! I don't own it; I just was lucky enough to run into one at the university of Dresden, Germany. So far they had only used it for titanium (for hip replacement parts) and they wanted to acquire some experience with light alloys, preferably producing something that would be impossible to produce any other way, so they could say: 'Hey, look!'
And there I was, right time, right place, right project. My exhaust and transfer duct designs were a piece of cake, but I had some wild ideas about cooling ducts everywhere....
By the way: it's not 3D printing. It's not printing at all; it's selective laser melting. With printing you deposit material; with melting the material is already there, in powder form. You just melt it where you want it solid.

[Frits Overmars]

@TZ350: no matter what you use to fill the coolant volume of a liquid-cooled cylinder, heat transport will always be far worse when the cooling medium is stationary. Liquid cooling works not because of the liquid but because of the flow. Heat moving through any metal is much, much slower than heat carried from one place to another by a moving medium.

[Muciek]

If you are looking for huge air cooled radiator check out CZ 516 cylinders and head , they are cheap and they have pressed in liners.
http://www.kartsandparts.ca/store/images/T/PB070015.JPG

http://www.kartsandparts.ca/store/images/T/b9_1_b.jpg

[Frits Overmars]

they are cheap and they have pressed in liners.

Cylinders with pressed-in liners just cannot be cheap enough. Read and shudder: http://www.gruppofrattura.it/pdf/ext...%20No2/001.pdf

[Muciek]

Nice pdf I didn't know it's such a big difference between cast in liner and pressed one I was wondering why TZ wouldn't just bore out old liner weld some material to radiator then make some 3 port EX with reliable bridges ect., but this is my answer I think

[husaberg]

sand printing I had seen this a while back not the same as a craftsman makings his own. lots of materials required, but i can see much like CNC vs manual lathe work. Of course you need the 3D model but we are an ipod generation.........

[TZ350]

Liquid cooling works not because of the liquid but because of the flow. Heat moving through any metal is much, much slower than heat carried from one place to another by a moving medium.

Yes I understand that.... but



We have to do our best with what we have chosen, follies of youth and all that .......

[wobbly]

Generating the 3D models is the part that is ignored by many when talking about creating parts with printers/laser/CNC technology.
This is a huge part of the overall time consumed in any digital driven process ,as you must create a perfect 3D replica on the screen of any part you need to make, no
matter what the end process.
And sadly the same thing applies to 3D modelling as it does to old school CNC machining.
In my opinion it is all but impossible to be a "good " CNC operator unless you have had a good grounding in the art of manual machining.
All that being part of the iPod generation means is that you are good at pressing buttons quickly, and has nothing to do with being able to create an engineering part
that has everything in the right place AND structural integrity etc etc, and dont get me into the aesthetics discussion or I really go off.
The CAD guys at Aprilia created some really superb work on the screen, that was then translated into beautiful solid engineering from people with the vision of what it should "do " like Jan.
You have to have all the elements in place to do this type of work well - the overall vision, the tech expertise in design, the modelling skills and finally the machining skills to translate all the hours of unseen work into
the final product, none of it is easy as is proven by the fact so few get it right.

[F5 Dave]

Cylinders with pressed-in liners just cannot be cheap enough. Read and shudder: http://www.gruppofrattura.it/pdf/ext....6 No2/001.pdf

Thanks for the read, but what I take away from that is from a thermal conductivity point of view, it would seem iron liners are pretty poor even if cast in. In fact, - if you make a reasonable job of pressing one in, you might outperform a bad design of cast in iron liner. That I did not expect. I would have though pressed in would have been considerably worse.

If you consider that you can't get better than a straight iron liner if you are using one (ie old engines like we use), the casting ranged from 92%-51% efficent, a huge swing. The pressed in one at 66% doesn't seem so bad. Well at least by comparison.

tangent 2:
What it didn't make clear was in real life these ally liners would be plated. Where these I wonder? or is there a further dissimilar metal junction loss to be considered?

tangent 3:
And why, why didn't they test an ally liner pressed into an ally casting? That would have shown if, being that iron bores are a problem there is any point of making a replacement ally liner.