The Bucket Foundry

[Grumph]

Just wondering if, at the part load HCCI operating regime, that if one could simply turn on the "glow plug(s)" to provide some additional extra localised heat to initiate combustion. No idea if it would have enough thermal capacity though. Alternatively a retractable "hot spot" shaft(?), utilising the heat from the previous cycle (whether it was HCCI or not).]

I may well be wrong but Neil's HCCI is the only one I've seen with no "conventional" ignition running in parallel with the HCCI events.
If the car engines are getting HCCI at part throttle, surely the rest of the time they're relying on the spark ignition ?

Anyone know better ?

[Frits Overmars]

Spent yesterday quietly going over the ignitech setup and found a few things, First, the cheap arse coils I was provided with the unit I can't trust.

Their pickups used to be (and maybe still are) rather dodgy as well. We used Honda pickups instead.

When the Boyer-Bransden ignitions were new to the market, no less a person than Paul Dunstall managed to blow a unit while installing it.
He found a path to earth that B-B hadn't forseen - himself...Came as a bit of a shock apparently... They changed the installation instructions forthwith.

Just wondering if, at the part load HCCI operating regime, that if one could simply turn on the "glow plug(s)" to provide some additional extra localised heat to initiate combustion. No idea if it would have enough thermal capacity though. Alternatively a retractable "hot spot" shaft(?), utilising the heat from the previous cycle (whether it was HCCI or not).

Glow plugs can provide plenty localized heat but I know the buggers from model engines, and they are a real pain: they advance the ignition as the cylinder filling improves, exactly the opposite of what you need. That can easily lead to deto, which will destroy the plug filament in milliseconds.
Apart from this, glow plugs would be far too slow in varying their temperature for decent ignition timing control, which might also be true for 'hot spots'.

But the key word here is localized. Spark plugs, glow plugs and hot spots all initiate combustion locally. And then it's not HCCI anymore.
Locally igniting a mixture that is already on the brink of self-ignition is asking for deto.

Flettner reckon you should concentrate on the gyro engine, after all it's just about there!

From a commercial point of view you are probably right Will. Me personally, I'd love to witness all his other projects reach maturity.

Wasn't Honda acheiving that 30 years ago with the traping valve on the EXP2. (The EX gas recirculation)

Yep. It's a bloody shame the Honda politicians blew the whistle on the Honda engineers.

I may well be wrong but Neil's HCCI is the only one I've seen with no "conventional" ignition running in parallel with the HCCI events.
If the car engines are getting HCCI at part throttle, surely the rest of the time they're relying on the spark ignition ?
Anyone know better ?

I think you're right.

[Flettner]

Spoils of the home foundry, all heat treated and nice to machine.
Just got to make this epicylic crank fit this case. Then for the special top end.

[WilDun]

Wasn't Honda acheiving that 30 years ago with the traping valve on the EXP2. (The EX gas recirculation)

Yes, I think that is the one I was thinking of and which I mentioned of a couple of posts back.

Spoils of the home foundry, all heat treated and nice to machine.
Just got to make this epicylic crank fit this case. Then for the special top end.

Guess we'll all have to wait and see which one it'll be!

How about flats on the big end eye running against bearing pads (crosshead style) to stabilise it? too much drag perhaps?

Everything is already a completely new concept top to bottom - let's have a go anyway!

If the car engines are getting HCCI at part throttle, surely the rest of the time they're relying on the spark ignition ?

We'll have to wait and see what Mazda have come up with as well! but, if it's anything like their great "engine stopping/starting gimmick at standstill" (trying to emulate Prius) then I wouldn't be holding my breath!

[Frits Overmars]

We'll have to wait and see what Mazda have come up with as well! but, if it's anything like their great "engine stopping/starting gimmick at standstill" (trying to emulate Prius) then I wouldn't be holding my breath!

I think Mazda have something pretty good this time (although not very KISSable). But they're still using a spark plug.

[WilDun]

I think Mazda have something pretty good this time (although not very KISSable). But they're still using a spark plug.

KISS is really a concept which is dying out these days.
Retaining a spark plug (just in case) reminds me of the cars of the fifties where they always had a crank handle (just in case).

Kickstarts seem to have disappeared from motorcycles too but that took a lot longer! (probably over about 50 years) - I think the electric start came out on the old Honda 50cc way back in the early nineteen sixties?

[Flettner]

beautiful to machine and not a void to be found.
Don't overheat the metal, use virgin bullet alloy and make sure you feed it well into the heavier parts of the casting. Use magnesium powder on the risers.

[WilDun]

beautiful to machine and not a void to be found.
Don't overheat the metal, use virgin bullet alloy and make sure you feed it well into the heavier parts of the casting. Use magnesium powder on the risers.

Looks good, - what sort of gauge do you use to measure the temperature of the melt so you know exactly when it's ready to pour? (or can you tell by just looking?)

I take it that you use huge risers to make sure it goes in properly? (got pics of those? to get an idea of proportion) Guess you get magnesium powder from the foundry materials supplier?

Are you now using Shellsand exclusively? - big improvement?

[Michael Moore]

A "K" thermocouple and cheap digital display works fine for aluminum, and you can source that at such a reasonable price these days that it really doesn't make sense to try and guess at the melt's temperature.

You don't want to use "huge" risers because then you end up with a lot of excess metal that gets cut off the part and which may not be quite as close to the original spec when remelted for another use. The feed/gating system volumes/areas can be calculated to keep the metal's progress in a range of speed that isn't too slow so that it freezes too soon but isn't so fast that you cause problems from turbulence entraining oxides or eroding sand from the mold and taking it into the part. Campbell's "Complete Casting Handbook" goes into a lot of detail on that (and many many many other things).

cheers,
Michael

[F5 Dave]

We don't get so much cast anymore these days but if they did as good as that I would be more than happy.

How would you go with an order for a few hundred that sort of size?

Where you say? Ohh that might sting.

[WilDun]

A "K" thermocouple and cheap digital display works fine for aluminum, and you can source that at such a reasonable price these days that it really doesn't make sense to try and guess at the melt's temperature.

Thanks Michael, I did actually buy a thermocouple a while ago but it was so ridiculously cheap that I didn't trust it! - maybe I should at least try it, but I'll probably need to make some sort of sheath to protect it and once I know where the proper temperature is on the readout, then I guess I'll know "when" and just disregard the actual figures it shows! (just used as a comparator I guess!).

You don't want to use "huge" risers because then you end up with a lot of excess metal that gets cut off the part and which may not be quite as close to the original spec when remelted for another use. Campbell's "Complete Casting Handbook" goes into a lot of detail on that (and many many many other things).
cheers,
Michael

Yes, and to be honest, as I don't know what sort of scrap I have, (all castings though) I think I'll just practice with that and purchase some "reliable" ingots to do the real thing.
Will check out that book, although I do have a Foseco book somewhere.

[Michael Moore]

You can get a graphite rod and drill down the center almost to the other end and use that as a protective sheath for the thermocouple. The thermocouple readers are readily available from eBay and similar sources, I think this is the same thing I bought:

https://www.amazon.com/Dodolight-Dig.../dp/B0084JQL1Q

Here's the Foseco book

http://www.eurospares.com/graphics/m...oundry-Man.pdf

Campbell was the originator of the Cosworth casting process and co-inventor of several other casting processes. His book is expensive, but at 1100 pages it sure has a lot of information in it.

cheers,
Michael

[Flettner]

all the parts fit, a bonus.

[ken seeber]

You can get a graphite rod and drill down the center almost to the other end and use that as a protective sheath for the thermocouple. The thermocouple readers are readily available from eBay and similar sources, I think this is the same thing I bought:

Here's the Foseco book

cheers,
Michael

Michael, you're right as to how cheap T/C controllers are and how good they are. We were fortunate in getting a couple of blind ceramic sleeves about 18 dia * 10 dia around 500 long. This allows us to leave the T/C in the melt for the duration (it controls the furnace burner), which is quite a few hours as we ladle directly from the furnace. Stainless steel, or even mild steel will disappear fairly quickly into the melt, destroying the quality of the melt at the same time. We also have a couple of others in the (permanent mould) dies so we can also control the temps of these.

Thnx also for the Foseco book, the one I have is much, much older, the new one has some good pics.

Mechanism looks good Fletto....another productive Sunday..

[Flettner]

yes went out to the shed to do a completely different job but bugger it I felt like machining something, it was raining, no better time to work on these sorts of things than a rainy Sunday afternoon.