i might be first to post..

bob g

while i own a couple of st heads i havent checked the waveform or taken one apart yet,but

i wonder if part of the problem is lack of skew in the stator

many years ago i built an old delco generator as a 3600 rpm alternator, complete with slip rings, as the fields were in the case i took the power off
the slip rings from the converted armature/rotor.  The unit had no skew and when checked produced a ragged waveform, basically there was spikes/dips in the waveform everytime the slots went thru the field.

as opposed to:

later i converted an old delco truck alternator, this one had a 4 pole rotor and a skewed stator, i rewound the stator and took single phase ac off of it
when connected to the scope it produced a very clean and properly formed waveform without all the glitches of the early machine.

in operation i couldnt tell the difference in the two, exept the ragged own had a higher surge capacity, easily starting a 3/4hp bench grinder

i suspect that most loads would not be effected by the power of an ST head, especially intermittent loads such as most household appliances.

most modern electronic devices have their own switching power supplies and are well filtered and shouldn't care much about the ST power
quality i would think.

bob g

Doug:

i didnt mean to make it complicated, just related what i was instructed to do by a motor winding guy as it relates to bringing out the 10,11 and 12 wires.

i am not sure but if memory serves me, the 10,11 and 12 wires are joined internally in a star configuration in US motors, is this true?

from my understanding of the setup one can either bring out these wires seperately or attach a lead to bring out the connection so as to double up the two sets and have the commons grounded giving three 120 volt hot leads at twice the capacity of the way i have seen on the internet articles where they only use one set of the winding and have no way to bond the grounds without shorting the other set of windings.

not sure if that is clear, i wish i could post a sketch, might make it clearer.

bob g

"IMO it's people not companies that can make the difference.. "

i would agree with that statement on the surface, but..

companies don't do, make or produce anything, ... people do and having said that consider this

it is damn near impossible today for an individual outside of a corporation to dream up, develop, manufacture and bring to market anything that hasnt been done to some extent better before.

consdering all the time, dollars, equipment etc to develop and get an idea to work, and once having it marketable, you better have deeeeeeep pockets to stand up to all the bureaucratic, regulation, inspection and litigation that will likely follow.

and then how many little guys have the bucks to do all the testing that is required, millions of cycles, millions of hours, or miles or whatever.

sure there is room still for the little guy to come up with some interesting concepts, and maybe a working model, but quite another to get it to pass all the hoops and make it to market.

say one does get past all the hurdles, and has a billion dollar idea or product, then you got the chinese knocking it off before you can gear up to fill the orders.

then from a liability standpoint you are on the hook "cradle to grave" in this country it seems on most stuff.

i fear gone are the days of hundreds of guys building the better mouse trap in their garage, and making money at it.

would that stop me, or rather should it stop you from experimenting?  no!

keep at it, who knows you might be one of the lucky ones and figure out something that hasn't been thought of yet. i just don't think i am that smart or have enough money or time to even entertain such an endevour.

if you do, then God bless you, go forth and prosper

bob g

"I am not sure how you lose track of 5000lbs of iron you have been mowing around for 20 years."

now that is funny,,, sadly it probably shouldnt be.

god only knows how much cool stuff is out there rotting into the ground, an example
years ago while searching for 55 chevy parts, i came upon a farmstead with an old dual glide harley complete with leather
saddle bags rotting into the dirt (axles down to about 2 inches from the surface, spokes down in the ground)
i asked how much? he asked what does a new harley sell for? i replied i dunno maybe 3 grand. his responce,,,, well  i want 3 grand for that one! i asked if we could dig it out and push it into the barn? he said no!! it has been there for 20 years and it will continue to sit there.  some peoples children!

sorry i digress and effectively highjacked the thread

back on topic...

folks get all upset and get offended at being challenged, or at least some folks. The thing is we as regular folks don't get to
see first hand the level of discussion such as that in a scientific forum or debate where opposing sides really go to town in what would appear to be nothing short of a knock down drag out war of words, usually without fists. After which they all go to the bar and laugh at each other and get along if not well at least cordially.

personally i have said and i will say again, if one is sure of his position he should be able to relate it without name calling or ridicule. Basically state your position and support it! Give alternative view points or at least alternative questions. It serves no one to beat each other up by debaseing someone, and it really becomes tedious to alot of other folks that come along the forum and the offending thread. I wonder how many folks (fearing a flame job) withhold good and pertinent questions, experience or information.

ok now how about a group hug.... lmao

bob g

how about we limit it too any one or two cylinder NON EPA COMPLIANT diesel engine!

at least then we can develop a large enough lobby to get some exemptions maybe.... perhaps,,,, ok i guess we won't


on a serious note, living here in the states there is a finite supply of original listers, and getting one as easily as our fellow board members that live in England or one of the commonwealth countries is definetly not a cake walk by any means.

so we were left with listeroids, petteroids, and yes like it or not changfa's, at least until the EPA ban. in this crazy ass country who knows how long it will be before they confiscate all of them anyway.... don't laugh someone is probably thinking about it anyway.

i personally don't think this board should be so narrow in scope as to orphan these other engines and their variants, there is at least some power and protection in numbers, and certainly a better chance of getting something done and gathering more idea's and experiences.

i have been involved with another RE board for a number of years, and when they decided to change the format of the front page to block out anything that was not approved by the admin and place elsewhere the whole thing took a dive in my estimation, too limited in scope.

sure not everyone or everything is directly connected to a <750rpm lister, but there are those that develope idea's, processes and procedures on other engines that simply will take their ball and go home if they feel excluded. This is a serious loss in my mind.

as a hypothetical example...

say i guy in brazil ,, working with a petteroid running at 1500 rpm,, works out the plans, developes and impliments an exhaust gas heat exchanger from something as simple as a pop can, he documents it, produces graphs of results and all sorts of pictures to support the project... all done using a brick and a rock to manufacture it... that would be cool and would probably have wide use in all sorts of small diesel engine includeing the lister/listeroids of <750 rpm. if he feels excluded where does he go?  maybe he just stays home and no one see's it.

i know this is an extreme example only made to illustrate my point..

my thinking is if one is to define the scope then dont narrow to much.  perhaps keeping with older design engines, such as the lister, petter, and ok,,, maybe the changfa to a lessor degree. make it all things that connect to the use of these engines, beit generation (with old generators, or newer alternators) heat exchangers (cogeneration) or as used to pump air/water or do useful work.

i dunno,,, seems like my government spends alot of time removing options, i really don't like the feel of removing options here.

bob g

damn i miss all the fun...
been so preoccupied with alternators i havent been keepin up on the rest of the board.

my take on pure vegetable oil in diesel engines, based on instincts and over 30 years working on diesel engines.

 a worn diesel engine such as an old 6.9 will probably burn vo and not do much damage to the engine, the old 6.9 was an indirect injection engine, and if there is enough wear in the injectors and pump, then it probably wont seize anything or cause problems with rings sticking or gumming up. also running a pickup at varying loads and speeds will probably keep most of the carbon blown out. it might also be worth noting that there is likely some engine oil leaking past the rings which will have a tendancy to preignite before injection raising combustion temps and knocking off a bit of carbon also. if i had clean straight vegie oil and an old 6.9 ford pickup i would probably run it and not worry alot about problems...

that being said, i would not under any circumstances run it in a modern 7.3 or 6.0 liter powerstroke or any other direct injection diesel with electronic unit injectors, reasons as follows

1. any acidity or alkalinity that varies from diesel fuel runs the very real risk of damaging very expensive injectors, last i checked can run 400 bucks each without labor to install them.

2. newer lower mileage engines fit tighter and rings may very well gum up, stuck rings cause all sorts of damage, such as burnt pistons and damaged cylinder walls (scoreing)

3. without solid testing of how vegie oil burns, and the flame propagation patterns within the combustion chamber however small it is, there exists the possibility of other problems, such as carbon chunks building up and breaking off and becomeing stuck to the sealing surface of the valves and seats. it only takes one small piece getting stuck under a seat under heavy load and high temps to adhere and cause the beginning of a burnt valve(s)

as far as burning it in a lister or a changfa, i am ok with it. lets face it, it doesnt take long to repair or decarbon one of these engines, and it is easy to tell when there is something amiss in a single cylinder before serious damage has occured. in an 8 cylinder engine, developing compression problems in one hole may not be evident until serious damage has taken place.

also in a stationary engine, usually the at the first sign of trouble the owner shuts it down to investigate, unlike a vehicle where you may not feel the problem in time or be many miles from home pulling a heavy load and decide to try and push or limp it home. And in doing so cause more damage.

as far as conspiracies go and the oil companies:

everyone has heard the story of the 100 mpg carb and how the big oil guys bought the patent rights or killed the guy or whatever.

the bottom line is anyone can modifiy a carb and an  auto to get incredible mileage, anyone!

the problem is one of driveability, startability, and reliability.

you set up a car to get that kind of mileage and no one will want to drive it much less buy it.

with literally hundreds of manufactures all over the world building cars and trucks it becomes insane to think that any one or all the oil companies could squeeze any one of them out. with competition what it is to sell cars if it was possible it would be done.

while i too think big oil is a pain, it is not the boogie man, trying to keep us in a box.

there simply is too many of us and the box is way to small.

there may have been a case or something to look at 40 years ago, when there was only the big three and amc, and the oil companies had enormous clout and connections.

the bottom line is there hasnt been alot of serious, scientific testing, with proper double blind testing on a large enough sampling of automotive engines to arrive at any solid evidence that burning straight vegie oil is ok in an automotive engine. There is however quite a bit of evidence that there are concerns that it will indeed cause problems. So untill there is a large study done no one can say for sure it is safe to do so.

so i guess do so at your own risk.

bob g