My Random Eco(no)-Related Things Thread

[Stubby79]

The synchronous speed for an AC motor is determined by

the power supply frequency, and
the number of poles in the motor winding.

The synchronous speed can be calculated as:

n = f (2 / p) 60 (1)

where

n = shaft rotation speed (rev/min, rpm)

f = frequency of electrical power supply (Hz, cycles/sec, 1/s)

p = number of poles

Electric motors - Synchronous speed vs. frequency and no. poles

I'd hazard it would only be running at like 600 rpm due to the number of coils in it. At 40rpm/v, it would only have 15v of back EMF, and the rest of the 208v or whatever it peaks at would have to be dissipated across the coils. It would get hot in a hurry.

The reasonable thing to do is to check the frequency of the output when spinning it. I'll do that next time I'm mucking around with it.

Edit:
1200rpm.

It's giving me 67hz at 1350rpm, which works out nicely to 1200 at 60hz.

[Piotrsko]

I love it when I say goofy things that make people do their own research

[Stubby79]

ARRG! I want that 30 seconds of my life back, you crook!

[Stubby79]

My job has been getting in the way of having any interest in working on anything. Well, not any more...

Finally got back to work on the electric bike/motorcycle yesterday. Swapped out the knobbly front tire for a street tire, cleaned up the severely rusty and ineffectual front brakes. That was as far as I got yesterday...

Just clapped a controller and battery in it for testing purposes, and took it for a very early test ride.

It worked much better than I thought it would! The motor appeared to have a wobble or imbalance when spinning freely(without a wheel/tire on it) on my bench. Was expecting it to be a deal breaker on the road...didn't feel it in the slightest. Bullet dodged; phew!

Thrilled. Sooo much more to do on it, though...this was the bare minimum to test it...smooth tires and operational brakes.

Fork angle is very laid back, like a chopper (and certainly resembles one with that 21" front wheel) and came across as alarming how much effort it took to get it to turn compared to what I'm use to, especially for a "bike". How close I was sitting to the handlebars didn't help, as did how low the seat was...very much like the height and position I'm sitting in on my office chair typing -- nothing like the leaning down on the handlebars, able to stand to make maneuvers position I'm use to riding in. Very stable none the less. I see why big old Harley riders look like they're just sitting back doing nothing. Not sure that's what I want, though I like the look.

Welp, time to tear it apart. Have a wider rim, tire and and proper-sized spokes to put on the rear that I didn't have when I first started putting it together. Then I need to decide on the rear suspension...was going to go a bit lower, don't think I want to any more though...'course, I can raise my butt by installing an actual bicycle seat, but that won't do anything for the fork angle. Decisions, decisions...

[Piotrsko]

Probably too much trail built into the fork. Harley riders like a big stable straight road ride because most of the roads are straight or high speed freeways and twitchy steering is disconcerting.

[Stubby79]

Random screwing around of the day...

Was looking up some info on a couple of my smaller engines, and discovered that my flat-head 97cc engine is a honda Gx100 (old style) clone. Well, maybe that means a Gx160 carb will fit on it?



Yup!

Test ran it on propane for a bit, worked well.

Linkage doesn't work the same way, and the bore through the carb is considerably larger (which might mean running it on gasoline might not go so well), but it ran well on propane.

Of course the propane flow control bit decided it wouldn't shut off completely even with no vacuum on it, which isn't right.

This thing:



That's the second one of these that's had an issue. The last one didn't have a hole drilled in it to allow the gas to pass through at all! (I guess that's what I get for buying the absolute cheapest ones I could get my hands on...they're probably rejects).

This is what's inside one:



A simple diaphragm connected to a spring loaded lever/valve. Even a tiny amount of vaccum gets amplified enough to actuate the valve...vacuum created across a venturi in the carb (like the one for gasoline, but it's larger and wide open) which then turns on the flow of propane gas...the more air flowing through the carb, the stronger the vacuum and the more gas that will flow...but it also means with no vacuum, the gas flow is shut off. Or it's supposed to, anyway.

Look at the top of the "bowl":

Little bits of rubber flashing. One of these was stuck to the lip of the valve, preventing it from closing all the way.

You get what you pay for. You wanna save a buck, it'll mean more leg work. (Maybe I should stop being so cheap, since I'm not actually as poor as I act)



On a completely different note, the power was shut off to my building all day as they replaced a power pole up the street. Fortunately, I have a 5kwh, 72v battery sitting on my work bench and a matching 2kw sine-wave inverter. Unfortunately the BMS kept deciding to shut off for no apparent reason and had to be bypassed. After that waste of time, I was the only one on the street with power.

My computer and the internet were only using ~130 watts. Full size i7 desktop, potentially power hungry video card, screen, printer, cable modem...using the power of a couple of incandescent bulbs. Crazy.

I plugged the fridge in too. It was only pulling ~150 more watts when running.

Things sure are crazy efficient these days. 8 hours without power barely put a dent in the 5KWH.

[Stubby79]

Deals from this week!

"Free" laptop & $30 for barely used Skull candy bluetooth headphones($130 retail). Covid included at no extra cost!



Free engine off a scrap pile!





Cleaned up nice:



Engine was a pleasant surprise...even if it didn't work, its got plenty of useful parts. Looks like it had been sitting outside in the weather for a season or two. Wouldn't start. No spark. Disconnected oil level switch, spark came back. Poured out what little oil - with a bit water mixed in - was in it, refilled, fired up first pull(not even...I was half way through the pull and it lost all resistance as it started spinning faster than i was pulling it!). Purred like a kitten. Quietest small engine I've ever had.

Carb leaks, appears to be float valve. Between that and the no-start, they probably presumed it was dead and replaced it with a cheap knock-off.

It's at least 9 years old, probably more. Real made-in-Japan model. Nice! Should last forever.

Headphones were just a craigslist-like deal I found online. Guy practically dropped them off on my door step. (5 minute walk to the nearest coffee house)

Free laptop? Well, pretty much. Or in exchange for labor I wasn't expecting to get anything back for...was actually searching for a video card for a buddy, came across a gaming laptop for $330 (like $250 US). Was at a pawn shop; decided to check it out. Of course it followed me home, since it checked out. Fought with it for a couple of mornings...I've forgotten how SLOW real HDDs are. Dear god. Finally got a game on it, played it beautifully...very impressed.

Was going to keep it for myself, though I told buddy I was going to check it out on a whim - he was looking to build a gaming PC for his wife to replace her broken laptop. Thought it was way too much power for he needs...he talked of her playing really lame older games. But I didn't have much use for it either, so I inquired further. She only played lame games because that's all her laptop could handle. She's actually a gamer. Well then - perfect. Was going to go to waste in my hands, thought it would go to waste in hers, but apparently not. Told him he could have it for her.

Stuffed an SSD in it - it had a separate NVMe slot! - fought with trying to move windows over from the HDD. Gave up and installed it clean. Not gonna bother trying that again - skip messing with HDDs, go straight to stuffing a SSD in the next one and install windows fresh.

Brought it to him that night. Turned out to be her birthday, so I plowed through that morning to get it ready. He told her he was handing over her old laptop for me to fix, and came back in to the house with this mint condition gaming laptop 5 minutes later. She was thrilled. I got a free laptop.

I had it apart within 15 minutes of getting home, and my spare SSD stuffed in to it, windows was installed and ready to go within the hour. (and when I say I had to take it apart, I mean I really had to take it apart to get at the HDD).

It's perfect for me. Cheap (free). Low-power (i3 4th gen, 2 core, 4-thread, whopping 2.1ghz fixed speed)...uses all of 15 watts (30 when charging the battery) with the CPU pegged. 12 GB of RAM (I upgraded it for him a year or two back), full 1080p, handles youtube at 1080/60 no bother. Quick with the SSD in it. No guilt that I've got more power than I have any use for(I'll play games on my desktop, thanks).

Ordered a new keyboard for it, for all of $16.50. Missing a key. Not a deal breaker...but I want to get rid of the silver bezel around the keyboard anyway, so might as well get it all done at once.

Got a wired keyboard for the first time in over a decade too for $10. Backlit. Wanted a bit more space for my mouse on my desktop (keyboard and mouse sit on a drawer made for the task), so was looking for a square-edged keyboard. Turned out to only save me half an inch...it has notably bigger keys. Gotta get used to it...though judging by all the words I've regurgitated in this post, it's working out fine.

If you've read this far, you get a gold star for effort. Only half off topic with the computers and headphones...getting good deals, saving money...ECOnomy...

BTW, loving only spending $10 a week on gas (at $1.50 a liter) for my commute to work in the Insight. Getting a solid 65MPG now that the mornings aren't close to freezing any more. Yay for being a cheap-ass!

[MetroMPG]

Nice scores!


What will you do with the engine? Re-sell or mount it on your bicycle?

[Stubby79]

Bicycle!

[Stubby79]

Upon further inspection...



Uht-oh, no air filter. Not a good sign.



Not pretty.



Yummy.



No better down the intake port.



That may be a problem!!



Looks fine in there, at least.



And in there. (fine grit - aluminum oxide and dirt - fell in taking off the muffler)

Well. That carb sure is pooched! It must have run yesterday off of the gas that overflowed from the carb! No way any gas was getting through that otherwise. Total fluke it ran at all!

Gotta be the worst carb I've ever opened up.

Cleaned up the intake...



Tried to drain the gas from the tank through the fuel line...barely dribbled out. Gave up and flipped it over a funnel. You can see the water in the fuel when you shake it up:



Needed some more cleaning with the tank off:



Everything got cleaned, save for the carb; it's a lost cause. Then I put it back together with the propane carb from a previous post, and ran it for a couple of minutes to mix up the oil and remaining water still in the crank case...



Milkshake! And that with the fresh oil put in yesterday.

It's been drained, and is sitting on end on a piece of card board to let every last drop of liquid come out.

Ran well. Thrummed along happily. Compression seems decent, and it doesn't burn oil, so I see no reason to tear it part to check that the bore isn't scored up from sucking in dirt/sand without an air filter. No junk in the cylinder - blew it out with the spark plug out. None in the muffler, either. Going with the hopeful theory that someone borrowed the air filter before it sat outside, then the intake got rain in it. Or there was so much in the gas that when the carb over-flowed, the gas and water sat in the intake. Intake valve was surprisingly spotless. Piston only had carbon on it. Spark plug was in great condition. No reason to think any got in to the cylinder.

Time to debate if I want to buy a knock-off carb(one with a built in petcock like the original, since the gas tank doesn't have one on it), another propane carb (for the other engine), or what...and wait for some 10w30 to come on sale, or go digging in my shed to see if I have any. (none of my cars use such heavy oil, don't keep it laying around). Or just run it with 5w30.

Vhatever. It's done until I find a use for it.