Author Topic: Treadmill Dyno  (Read 120875 times)

0 Members and 1 Guest are viewing this topic.

zap

  • Hero Member
  • *****
  • Posts: 1116
  • There's an app for that
Re: Treadmill Dyno
« Reply #54 on: February 26, 2011, 12:14:49 PM »
Nice video... you boys are having way to much fun!

924 watts =1.2hp?  How warm is the treadmill motor getting?

Once again... thanks for all the info you keep providing.

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #55 on: February 26, 2011, 01:19:20 PM »
Here was the original set up with the chain.  It was getting really jumpy around 60v.

http://www.youtube.com/watch?v=5OIXyeXDMhw

Quote
Nice video... you boys are having way to much fun!

924 watts =1.2hp?  How warm is the treadmill motor getting?

Once again... thanks for all the info you keep providing.

We always have a lot of fun!  Several of the videos I will not post because something distracting happens or something goes wrong.

As for the the 924 watts, I believe the governor is way too low.  If the top rpm was only 105*33 = 3465 rpm, then it is set too low.  I know we hit at least 5,000 rpm last year in competition.  The data with the engine suggests a max rpm of 4000 rpm for extend run times.  Peak torque is supposed to be 4.9 ft*lbs at 2800 rpm.

Here is the official data:
http://www.jackssmallengines.com/bs35horizontal.html

Also, the belt was getting pretty warm, so I bet it was only 90-95% efficient.  As for the motor, I ran it at full throttle for probably 5 minutes and it wasn't cold anymore, but it wasn't hot, maybe 90 F.

I am wondering what the efficiency of the treadmill motor is.  Maybe we will hook up another electric motor to the treadmill motor and see what we can figure out.  Does anyone one have any data on this?


EDIT:  Also, would any one know if the torque required for the treadmill motor is an quadratic function?



« Last Edit: February 26, 2011, 01:26:08 PM by taylorp035 »

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #56 on: February 26, 2011, 08:24:31 PM »
Here is the last video, with all 10 light bulbs. Sorry it took me so long to upload it...

http://www.youtube.com/watch?v=0y64QiC9mkA

The output was between 67-69v @ a calculated 13.6 amps. The rpm was only about 2200, so it was obvious that the treadmill motor was winning the torque contest.

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #57 on: February 27, 2011, 03:19:14 PM »
I have been thinking about how I am going to find the absolute efficiency of our engines.  It will be easy to compare the fuel usages between the engines at a set power and rpm level, but actually getting a percentage is going to be difficult.

Idea #1 would be to take the hp graph from the manufacturer and compare it to the fuel usage.  This would only be accurate if our engine actually puts out what its supposed to.

Idea #2 would be to do what the wind folks do around here and make a lever arm scale thing that measures the torque.  This would only be as accurate as the scale reading * the rpm accuracy.  I'm not sure how I would find the torque, since both the engine and the motor would need to be clamped down to a table.

Idea #3 is to try to calculate the efficiency by comparing it to last year's results.  This would be an average efficiency, which isn't what I want, but it would work.  According to the numbers, it should be between 9-10% efficient, which I am fairly confident about.

Any ideas out there that I could do to find the efficiency?


SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #58 on: February 27, 2011, 03:46:26 PM »
Got a lathe?

On my pages, look for the alternators, the Baldor conversion, and near the end is the load test.
www.sparweb.ca

It's really really that simple.
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #59 on: February 27, 2011, 04:02:39 PM »
Well, I have the exact same scale, but the lathe may be a little tricky.  Mine at home wouldn't have enough power or clearance and the one in our lab is way too small.  We could use our mill, but I would have to put the motor in a 3 jaw jacobs chuck.  Maybe I should put it in a 5/8" collet instead.  I don't remember the hp rating on the mill, but it's 240v, so probably at least 3 hp.  The same mill at my high school had a 10hp motor.


« Last Edit: February 27, 2011, 04:30:15 PM by taylorp035 »

SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #60 on: February 27, 2011, 04:26:21 PM »
I watched a couple of your team videos to see how you're set up.
If the vertical mill doesn't work, you could rig up with the engine test bench you already have.  I think so at least - it would take some fabricating of a mount for the electric motor that allows it to rotate freely...  It will take some though to set it up right, but it seems like a mount for the motor like a baby cradle, whose axis is co-axial to the motor shaft would permit freedom to rotate the motor, yet keep the motor properly aligned to the motor.  Its freedom to rotate is resisted by the long-beam.  I can't tell if that came across clearly in words so just write back after trying the milling machine, if you want another option.
Depends on how badly you want the numbers.
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #61 on: February 27, 2011, 04:27:23 PM »
Oh yeah (duh) the other way is to prony-brake the B+S motor of course!
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #62 on: February 27, 2011, 04:50:55 PM »
Well, we have the water break for the dyno and it is all set up and working  BUT, the water break is so uncontrollable that it will just stall out the engine and no data can be taken.  Putting the motor in the mill will be far the best option.
« Last Edit: February 27, 2011, 05:39:06 PM by taylorp035 »

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #63 on: March 03, 2011, 06:14:04 PM »
Today I had a little time to mess with the dyno, so I hooked up our new analog 30 amp meter to the light bulbs.  I also hot glued all of the loose wires and things.  We maxed out  (with the governor) at 66 volts @ 16.5-17 amps.  This means there was about 2 hp at the shaft of the engine.  Interestingly, this is about 25% higher than we predicted using ohm's law.  I measured the bulbs with the multimeter today and it said 4.6 ohms, but when we do the calculations, they should be about 50 ohms.  I imagine the resistance goes up as the filaments heat up.

Tomorrow is the fun day, where we will hook up the burret to the gas line and take the governor off.  I will have to see how warm the treadmill motor gets, especially  when generating 20-30 amps for several minutes.

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #64 on: March 05, 2011, 01:39:20 PM »
Hi guys, I know you guys have been waiting patiently for some results, so here they are.  I have 3 videos that really show how the whole thing is set up, the last one is still uploading.  I will get you some data, graphs, and temps of the treadmill motor in ~2hrs.

http://www.youtube.com/watch?v=6NPW412Fi1s

http://www.youtube.com/watch?v=nPyQXx92IFM

and here is the 3rd video:

http://www.youtube.com/watch?v=0Y3JSa3i5HI



EDIT:

Q:  Does the motor get hot and under what loads?

Well, we ran the engine for about 2 hr's straight at full throttle with approximately 1 minute breaks between 2-3 min long runs.  Even after a good 1/2 hr of generating 800-1000 watts, the motor was in the 110-130 degree range.  There is no fan on this motor to cool it down. 

Q:  How much power can you get out of the treadmill motor?

Haven't found the upper limit yet.  Our highest data point was at 75v @ 17.4 amps = 1305 watts, which represents 10 -300 watt light bulbs with the stock engine past the governor.

Q:  What efficiencies did we achieve?

We don't know the efficiency of the treadmill motor or the v-belt, but I assumed a constant 80% for the motor and 95% on the belt.  This comes out to 76%.

If you assume the constant 76%, the engine peaked at ~14.2% efficient + or - 0.2%.  Below or an another post, I will copy my table of data for you guys to see.

Q:  How was efficiency calculated?

The dyno was set up with the engine and the treadmill motor connected with 3" pulleys and a v-belt.  The gas was measured using a 50 cc buret connected.  What we did was we filled the buret past the top with fuel and then we started the engine.  When the fuel passed the "0" mark, we started the stop watch, and we stopped the timer after it passed the 30 cc mark.  This allowed us to get very accurate measurements, within 0.5% roughly.  While it was running, we observed the voltage and the amperage.  The data was then put into an excel sheet where all of the necessary conversions and calculations were made. 

Q:  Were the results repeatable? 

Yes,  we could do the same run several times in a row and only have variations like these -->   0.1393, 0.1431, 0.1386, 0.1414.   Usually the runs were even closer than this.

Q:  What is next to do?

Find the efficiency curve of the treadmill motor by using the vertical mill with a scale or a torque cell.  Also, I would like to get at least a few data points from the EFI engine, even if it is really hard to control.  Visual observations from the few test runs with the EFI engine showed that it really likes to guzzle gas, but nothing has been proven yet.



« Last Edit: March 05, 2011, 03:22:09 PM by taylorp035 »

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #65 on: March 05, 2011, 03:43:36 PM »
Volts     
92
89
91.2
91.2
92
65.5
77.5
78.5
78
78
63.5
63
66.7
66.5
69.8
69.2
73
71
75.9
79.5
79.5
83.5
88
87.5
92
91.6
96.7
96.4
96.5
100.8
75
53.6
62
44.7
43.7
Amps   
6
5.9
5.8
5.8
5.9
5.1
10.7
10.7
10.7
10.7
16.2
16.1
15
15
13.7
13.7
12.1
12.1
10.7
9.1
9.1
7.4
7.8
7.8
6
6
4.1
4.1
4.1
2
17.4
15
15.2
13.7
13.4
Watts   
552
525.1
528.96
528.96
542.8
334.05
829.25
839.95
834.6
834.6
1028.7
1014.3
1000.5
997.5
956.26
948.04
883.3
859.1
812.13
723.45
723.45
617.9
686.4
682.5
552
549.6
396.47
395.24
395.65
201.6
1305
804
942.4
612.39
585.58
Gallons               
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
0.007925162
Seconds   
160.22
187.64
165.05
174.87
161.79
248.25
133.57
135.47
132.11
134.76
110.2
110.32
114.58
113.97
115.81
115.24
120.11
122.76
128.84
141.81
138.94
148.97
140.75
145.64
159.05
159.74
177.1
177.94
178.76
201.2

134.77
116.5
169.59
163.75
Joules/s               
6529.280526
5575.150959
6338.208579
5982.280128
6465.920798
4213.983186
7832.00813
7722.162294
7918.562758
7762.847476
9492.933992
9482.608103
9130.051719
9178.918364
9033.082859
9077.762287
8709.69383
8521.679097
8119.538388
7376.922121
7529.302763
7022.362395
7432.478337
7182.925885
6577.311071
6548.90025
5906.952716
5879.067809
5852.099608
5199.410169
#DIV/0!
7762.271469
8979.582197
6168.531906
6388.527181
Est. RPM
3036
2937
3009.6
3009.6
3036
2161.5
2557.5
2590.5
2574
2574
2095.5
2079
2201.1
2194.5
2303.4
2283.6
2409
2343
2504.7
2623.5
2623.5
2755.5
2904
2887.5
3036
3022.8
3191.1
3181.2
3184.5
3326.4
2475
1768.8
2046
1475.1
1442.1
Efficiency       
0.111239789
0.123928672
0.109810208
0.116343599
0.110457667
0.10430499
0.139315282
0.143120194
0.138681466
0.141463284
0.142585278
0.140742425
0.14418838
0.142990704
0.139292074
0.137415038
0.133441756
0.132649296
0.131607495
0.129038626
0.126427098
0.115776753
0.121515039
0.125022356
0.110427465
0.110424326
0.08831475
0.088458349
0.088958176
0.051017933
#DIV/0!
0.136286748
0.138091057
0.130626919
0.120606828
Shaft HP       
0.974006656
0.926541477
0.933352465
0.933352465
0.957773212
0.589432832
1.463215615
1.482095817
1.472655716
1.472655716
1.8151461
1.789737231
1.765387064
1.76009355
1.687325371
1.672821142
1.5585871
1.515886084
1.433007293
1.276531006
1.276531006
1.090287523
1.211156103
1.204274534
0.974006656
0.969771845
0.699573223
0.697402882
0.698126329
0.35572417
2.302678779
1.418661869
1.662869335
1.080565102
1.033258728
Notes 
Full Bunny, 3 Lights
Full Bunny, 3 Lights
Full Bunny, 3 Lights
Full Bunny, 3 Lights
Full Bunny, 3 Lights
Partial Throttle, 3 Lights
Fully Bunny, 6 Lights
Fully Bunny, 6 Lights
Fully Bunny, 6 Lights
Fully Bunny, 6 Lights
Full Bunny, 10 Lights
Full Bunny, 10 Lights
Full Bunny, 9 Lights
Full Bunny, 9 Lights
Full Bunny, 8 Lights
Full Bunny, 8 Lights
Full Bunny, 7 Lights
Full Bunny, 7 Lights
Full Bunny, 6 Lights
Full Bunny, 5 Lights
Full Bunny, 5 Lights
Full Bunny, 4 Lights
Full Bunny, 4 Lights
Full Bunny, 4 Lights
Full Bunny, 3 Lights
Full Bunny, 3 Lights
Full Bunny, 2 Lights
Full Bunny, 2 Lights
Full Bunny, 2 Lights
Full Bunny, 1 Lights
Full Throttle, 10 Lights
Partial Throttle, 10 Lights
Partial Throttle, 10 Lights
Partial Throttle, 10 Lights
Partial Throttle, 10 Lights
[/td][/tr][/table][/td][/tr][/table]


Note:  These graphs have not been corrected for the efficiency of the treadmill motor or the actual rpm.  The rpm is based on a steady 33 rpm / volt.







Some things to notice:

The efficiency went down as the voltage went up.  This is due to the higher rpms could only be achieved with a smaller load, which is less efficient.
Only 5 tests were done at partial throttle.  More of these tests would make the results better.


EDIT:
Here are some more things I found:




The 5 points that are not on the voltage vs torque curve were the partial throttle runs


« Last Edit: March 05, 2011, 04:32:45 PM by taylorp035 »

SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #66 on: March 05, 2011, 09:47:21 PM »
First I have to say this is a lot of work! 

I have to ask about the ~15-20% efficiency, though.  Going back to this one:



Am I seeing the high-RPM end of the engine's efficiency curve?  Is the efficiency of the engine alone represented here, or is it engine efficiency X the motor's efficiency?

The reason I ask is that I did tests like these ones in college (mighta mentioned before) and though it was a V-8 Ford, I wouldn't expect the B&S engine to be THAT BAD.  The Ford had a volumetric efficiency peaking in the 70's (IIRC! it was a long time ago))  and the mechanical efficiency was around 50-60%.  Do I remember that wrong, or is the difference between a V-8 and a 1-cylinder engine that great?

It would make more sense if we were looking at 40% (engine) X 40% (motor) = 16% efficiency of the two coupled together.  (or some variation of their proportions leading to the same result).

Is this with or without all the engine mods you told us about last month?

What happened on the data line, fifth from last?
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #67 on: March 05, 2011, 10:25:53 PM »
Quote
What happened on the data line, fifth from last?
That was our peak power on the stock engine.  I had to manually hold the throttle wide open so the governor wouldn't slow the engine down, hence there is no time value for it. 

Quote
Is this with or without all the engine mods you told us about last month?
100% Stock, less than 1 hour of run time on the engine.

Quote
It would make more sense if we were looking at 40% (engine) X 40% (motor) = 16% efficiency of the two coupled together.  (or some variation of their proportions leading to the same result).
The efficiency value you see is the calculated engine efficiency, including the losses from the treadmill motor @ 76% efficient.  The calculation is really more like (Watts measured / 0.76) / power in gasoline.

And yes, the Briggs engine is that bad.  The number is probably closer to 12% peak efficiency b/c I think my 76% for the treadmill should be closer to 85% * 95% = 80.75%.
The reason it's so bad is because it is an "L-Head" design, instead of an overhead cam.  Also, the compression ratio is kinda low, so thermodynamic efficiency could be higher.





taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #68 on: March 07, 2011, 08:24:01 PM »
On Wednesday, there are some serious plans to figure out the efficiency of the treadmill motor.  I will try to get some lower rpm readings so the wind community can utilize the data.

I would like to answer several questions which include:

Is the RPM / Volt a real constant, or does it vary with current or rpm? [with a load like light bulbs, not batteries]
Does the efficiency change over the rpm range, voltage range, current range, or a combination of the three?
What is the loss in the bearings and v-belt?

I hope to remember to use the Doc Watson meter for the lower power levels so I can get more accurate power readings.  Maybe I will do both, so I can figure out my error in my previous readings.

Once I am done with all of this, I will take the data and make a real engine efficiency curve, which then can be put directly into my mpg calculator.  I am also considering putting the data into last year's data, so I can compare the results of my excel sheet with some real life numbers and possibly explain why we got 777 mpg on our 4th run instead of the 630,650,698 on the other runs.  I have some strong suspicions to why this is (engine has a low efficiency at the top rpm, which the 777 run was conducted by someone who was going 2 mph slower at the top speed).  The scary part is, 2 mph is all that it takes to drop 100 mpg.  That will double to 200 mpg with this year's car.


« Last Edit: March 07, 2011, 08:26:57 PM by taylorp035 »

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #69 on: March 10, 2011, 01:24:42 PM »
Yesterday I tested the efficiency of the treadmill motor on the vertical mill, using a torque arm set up and a scale.  I also got some corrected RPM/v values, which are mighty important.  Unfortunately, we did not have a good way to measure the rpm (even the oscilloscope was tried), so obviously the mill was running slower under load than the nameplate said.  If I had the rpm values, I could of calculated the efficiency in ~5 minutes on excel, but instead it took me 4 hours.  But, I did some cross referencing of my results to make sure they were accurate across the rpm and hp ranges.  The end result came out to something like this:




« Last Edit: March 10, 2011, 01:35:40 PM by taylorp035 »

SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #70 on: March 14, 2011, 12:20:56 PM »
.....  Unfortunately, we did not have a good way to measure the rpm (even the oscilloscope was tried), so obviously the mill was running slower under load

Bike speedometer?   Oh well I'm sure it's close enough.  The curve hasn't changed much since the last version, so presumably further refinements won't do much good.
Isn't it nice to have a project like this with nobody looking over your shoulder asking "what are the sources of uncertainty?".   :-\
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #71 on: March 15, 2011, 11:31:28 AM »
Quote
Isn't it nice to have a project like this with nobody looking over your shoulder asking "what are the sources of uncertainty?".
Yeah, I just finished a Physics lab course on optics and nuclear stuff, which we spent hours and hours figuring that stuff out.

In the last few minutes, we just found a paint shop who is really excited to give us a paint job on the car.

Earlier today, I hooked up our new box fan to our cooled seat, and I set a new record of 50.77 F, which is really cold when you sit on it.  I then hooked about 40' of 1/2" tubing to the whole system and a reservoir of about 1/4 gallon and turned it on.  It got down to 63F using about 140w of power.  I then put the tubing on a chair and sat on it for 5 min.  It was very effective.

Got to run!


Bruce S

  • Global Moderator
  • Super Hero Member Plus
  • *****
  • Posts: 4519
  • Country: us
  • USA
Re: Treadmill Dyno
« Reply #72 on: March 15, 2011, 01:36:20 PM »
Of course you know we're going to ask for a separate post on just the cooling setup of the seat.
I will certainly start the official request  ;D
Thanks
Bruce S
 
A kind word often goes unsaid BUT never goes unheard

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #73 on: March 16, 2011, 07:30:47 PM »
Oh, don't worry, I was kinda adding my knowledge to a thread in the heating section with the mini fridge.

http://fieldlines.com/board/index.php/topic,144978.54.html

I hope to make a new thread when I get some time and new photos + optimize the section.

I was thinking that this could replace an air conditioner in some one's house, so you only have to cool a seat.  The parts can be bought relatively cheap ($10 for the chip, $12 for the heatsink, $3 for some thermal grease, $20 for some nice rubber tubing, and a water pump good for 1-2 gpm.


As for the car, the paint place is going to do an awesome job (they want it to look nice), so they said they would do the filling and sanding for us (the worst part).  More on this next week when we go back to discuss things in more detail.

To get the car to the place, we shoved the car tail first into a mini van.  The tail was resting on the arm rests of the front seats and it barely fit.  Looks like we will need the extended wheel base minivan to get it to MI.



taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #74 on: March 22, 2011, 09:42:53 PM »
We officially gave the car away today for ~ 3-5 weeks to the paint shop.  We are unhappy that it will take so long, but it would of taken us at least 5 weeks of our own time to do it, so I guess we shouldn't complain.  Anyways, we can finish everything else without the car, like the large amount of wiring (bought a fuse board with powerpole connectors on it).  I may also wire up another "Y" to the battery connection so I can hook up 3 batteries instead of 2.  We will also program the computer and install it on the wheel skirt.  Also, the cooled seat will be finished (a carbon fiber air duct, a carbon fiber cup holder ;D ;D ;D , the cushion that the tubes run through, and the power switches).  Also have to wiring up the kill switches (I think 4-5 ), plus the master key(snowblower key) and master kill switch.

The dashboard will have to be designed and made, which will have to hold a bunch of switches, the 7" screen, a Doc Watson meter, and maybe an air/fuel mixture gauge.  The steering will be finished and the plate clutch will be connected to the big gear via a keyslot.  Last Friday I spent 2 hours taking of 0.002" off the 6 diameters on the rear axle with sand paper and a file.

Lastly, we will have to swap the brushless starter motor + custom flywheel off the EFI engine on to a stock engine.  We will have to rig up an ignition system somehow since there will be no magneto.

Sorry for the scrambled post.  More updates to come ;)




SparWeb

  • SuperHero Member
  • ******
  • Posts: 3219
  • Country: ca
    • Wind Turbine Project Field Notes
Re: Treadmill Dyno
« Reply #75 on: March 22, 2011, 10:05:54 PM »
... a carbon fiber cup holder ...

It's not the refrigeration system that makes your car cool...!
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

zap

  • Hero Member
  • *****
  • Posts: 1116
  • There's an app for that
Re: Treadmill Dyno
« Reply #76 on: March 22, 2011, 10:38:49 PM »
I can't seem to wrap my head around the "3-5 weeks" for paint! ???  It's such a tiny vehicle... and I would think not a lot of paint would be applied?

A 747 has about a 2 week turn-around for painting.
... more useless facts:
The average paint job on a 747 is around 600 lbs of paint.
A bare polished 747(my personal favorite for almost any aluminum skinned plane), with customer markings, has about 25 lbs of paint.
It generally costs more to operate a bare polished plane.
(http://www.boeing.com/commercial/aeromagazine/aero_05/textonly/fo01txt.html)

"4 minutes to paint a 747"
http://www.boingboing.net/2010/12/13/13-day-boeing-747-re.html

Bruce S

  • Global Moderator
  • Super Hero Member Plus
  • *****
  • Posts: 4519
  • Country: us
  • USA
Re: Treadmill Dyno
« Reply #77 on: March 23, 2011, 07:09:01 AM »
ZAP;
 I'm thinking it's the prep time to get the carbon fiber body nice & smooth then to layer up the paint with time in between to wet sand the body paint to get it back to smooth.
I'm looking forward to seeing how it looks.

Taylorp035,
What would have been neat to know, what did the car weigh before it went to the paint shop, then weight it afterwards  ;)

Thanks for the update, it does sound like you have a fair bit of work while the car is in the shop.
Are they going to have photos of the before , during and finish of the car?
That would be cool to see too.
Cheers
Bruce S
A kind word often goes unsaid BUT never goes unheard

taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #78 on: March 23, 2011, 03:19:27 PM »
The large amount of time will be because they have to sand it, fill it, sand it, repair any holes, sand it, paint two colors, clear coat it, and maybe a rally stripe.  Also b/c they are doing it for free.

As for weight, I don't have a clue.  It shouldn't be much.  The weight of the car was changing every week.  It should of been close to 40 lbs with nothing in it.


taylorp035

  • Hero Member
  • *****
  • Posts: 1009
  • Country: us
  • Stressed spelled backwards is Desserts
Re: Treadmill Dyno
« Reply #79 on: March 26, 2011, 11:53:13 AM »
After about 4 hours of running the EFI engine with the computer hooked up to it, there were some obvious things that were wrong, like the displacement (changed from 350cc to 150cc).  It was also obvious that it had never been tuned with a load on it, since it ran really nice with no load, but once we added 1/2-1 hp of load, it would stall out.  After a few minutes with the auto-tuner turned on, the performance was greatly increased.  We didn't do an efficiency run yet, but we were able to push 4,000 rpm with 5-6 lightbulbs, which translates to 1-5 to 2 hp at the shaft, at about 50-80% throttle.  With a bit more time, I bet we can tune the higher throttle levels with 8-10 lightbulbs and get 3 hp at the shaft.  As a reference, we measured the stock engine at 1.8 hp at the shaft.

Unfortunately, the engine gets harder and harder to start after you run it, which makes absolutely no sense.  Oddly though, a stock engine has the same exact problem.  Maybe something is expanding and a valve is not fitting?  It is an air cooled engine, and we were measuring temps past 260 F.

The starter motor held up very well, especially since we must of started it 200+ times, most of those with no clutch and hooked up to the treadmill motor.  We used the 30c 1350 mah 4s lipo batteries, which worked better than the 4s A123 pack.

In a about an hour, I will post a short video.

EDIT:
http://www.youtube.com/watch?v=cWUIFrfvJxk
« Last Edit: March 26, 2011, 12:56:32 PM by taylorp035 »

zap

  • Hero Member
  • *****
  • Posts: 1116
  • There's an app for that
Re: Treadmill Dyno
« Reply #80 on: March 26, 2011, 10:19:21 PM »
How much do you think you're losing with that belt flapping like it is?