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8" motor Helwig Brush Upgrade Bulk Buy...

22K views 32 replies 14 participants last post by  mharvey 
#1 ·
Hello,
I am replacing the brushes on an 8" Advanced DC motor (203-06-4001A). The new Helwig split redtop brushes significantly reduce heat (~20%), increase rpm (~20%), handle more amps without arcing, and give greater range (~13%). The latest EVTV show tests them and also has an informative video from Helwig at the end. This will give you more information about why these brushes are Much better than stock forklift brushes.

http://www.youtube.com/watch?v=PTPNag6O8vw&feature=uploademail

There is SIGNIFICANT savings to be had by buying in bulk. Here is the breakdown:

1 set: $225.00/motor
2 sets: $150/motor
3 sets: $130/motor
4 sets: $115/motor
5 sets: $110/motor
6 sets: $105/motor
12 sets: $95/motor

Obviously, there will be some minor shipping charges as well. I am definitely buying a set, so if there is anybody else out there who has a brush that is sized:
Length:1-5/16" (1.30")
Width:31/32" (.967")
Thick: 5/8" (.625")
Please reply or send me a pm.

Thanks!
 
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#5 ·
I'd say a whole bunch of those conversions are held up in garages because of crapped out lead acid cells and no longer used. I'd also bet many were just trashed because they were not used any longer and just wasted away. You may find some interested but those folks would have to be listening in and I'd bet most are not. Some yes but most, NO.

That is reality.
 
#4 ·
Well, frugality may be a factor, but size and weight are too. In our situation a larger motor would have been a difficult fit. Regardless of the reasons for purchasing an 8" motor. Once in service, if they are marginal then heat and arcing become issues and the upgrade should help those quite a bit.

Range is an issue for ALL electric cars so 13% more would pay for itself rather quickly.

Folks are finding that it does not matter whether they bought 8, 9, or 11 inches of motor. If they have forklift brushes then they are in for trouble, reduced efficiency and higher heat load. There is a reason the new Netgain motors come with the Helwig brushes. They found the other brushes to be inferior.

Cheers
 
#6 · (Edited)
Well this is a new low in electric snobbery.

8" brushed motor = no good scumbag lamo conversion.
9" brushed motor = awesome future tech amazing coolness.

get a grip. If an inch or 2 was that important our wives would have left long ago. ;)

It's about weight and size. Is 11" enough for a truck? maybe not. Each vehicle has a range of workable motors depending on desired use.

Obviously those poo pooing 8" motors haven't searched evalbum and seen how many nice conversions use them. Don't forget that even a couple of years ago the 8" motor was seen as an "unnecessary" upgrade to the 6.7" motor.

Now you are supposed to be embarressed with less than 9"?? :confused:

This thread is about upgrading brushes, not dissing motor size. If 8" sucks so bad, there should be a crowd ready to upgrade. The fact that I get little response suggests that those 8" motors are out there working fine. Where are the stories of failure? Isn't it the 9 and 11" fancy pancy Netgain motors that are going "boom"?

Please respond if you have something positive to say.
 
#29 ·
The fact that I get little response suggests that those 8" motors are out there working fine. Where are the stories of failure? Isn't it the 9 and 11" fancy pancy Netgain motors that are going "boom"?

Please respond if you have something positive to say.
What I have found is that on this board in particular, once a conversion is finished, people do not check the board too often. You would probably need to contact those with 8" motors directly to get a better result.

Dave
 
#7 ·
Hello,
I am replacing the brushes on an 8" Advanced DC motor (203-06-4001A). The new Helwig split redtop brushes significantly reduce heat (~20%), increase rpm (~20%), handle more amps without arcing, and give greater range (~13%). The latest EVTV show tests them and also has an informative video from Helwig at the end. This will give you more information about why these brushes are Much better than stock forklift brushes.

http://www.youtube.com/watch?v=PTPNag6O8vw&feature=uploademail

There is SIGNIFICANT savings to be had by buying in bulk. Here is the breakdown:

1 set: $225.00/motor
2 sets: $150/motor
3 sets: $130/motor
4 sets: $115/motor
5 sets: $110/motor
6 sets: $105/motor
12 sets: $95/motor

Obviously, there will be some minor shipping charges as well. I am definitely buying a set, so if there is anybody else out there who has a brush that is sized:
Length:1-5/16" (1.30")
Width:31/32" (.967")
Thick: 5/8" (.625")
Please reply or send me a pm.

Thanks!
Hi Ruckus

13% increase in range
- does not pass the smell test -
if 13% of your motor power was being converted to heat in the brushes brush life would be in the milliseconds

DC electric motor brushes are old technology - there have been thousands of engineering man years devoted to improving them

The new Helwig brushes may help us as we - abuse - our motors but 13% range improvement is silly

Saying that I'm going to measure my brushes and if they are the same size - you will be able to put me down as a possible depending on how many other people are interested and how far down your price curve you get
 
#8 ·
Hello,
Did you watch that EVTV episode? The 13% range increase was carefully documented by Tim Catellier on his BMW Z3. This is shown on his blog in detail: http://evz3.blogspot.com/ EVTV then did tests which confirm that it was the brush change that produced this effect. They ran the same motor back to back with different brushes and found 42F less temperature (21%), 600 more rpm (22%) at the same time using 77 watts less energy (14%).

So 13% would not evaporate the brushes in a matter of seconds, it just causes a lot of extra heat and lower performance/range.

Glad to get you on board. If you watch the show and read the blog I think you will be completely sold. I am thinking we could likely get Helwig to ship everyone their brushes directly. So It would be a "group" production run but each would pay and get shipped separately. This would avoid any risk.

Cheers
 
#9 ·
They ran the same motor back to back with different brushes and found 42F less temperature (21%), 600 more rpm (22%) at the same time using 77 watts less energy (14%).

77watts - 14% - power used - 550watts - that is the power with no load at 12v

Under load
300watthours/mile x 60 mph = 18,000 watts x 13% = 2.34Kw dumped into an area of just over 4 square inches - that is HOT

And that's at 18Kw - not the double or triple used to accelerate!

I have read the blog

Changing the brushes caused the no load speed at 12v to increase

After taking the motor out and working on it the power used appears to decrease

All good stuff but the physics of changing one part of an 80+% efficient motor and gaining 13% in efficiency....
Possible,
But then its possible I could marry Jenifer Aniston...
 
#11 ·
Well, there's only one way to find out isn't there? ;)

I have carefully measured the temperature of the motor after driving continuous at 60 mph. The temp is consistently between 250F and 260F :eek: measured with an infrared thermometer. I will install the new brushes and do the exact same drive and remeasure the temp. If the temp is less than the energy went into go-power instead of heat. I can easily get the brushes at $225 and do the experiment, I just wanted to save everyone some cash. Kind of that whole "work together community thing". :)

What confuses me is that we have 2 sets of empirical data which had the exact same outcome within 1%. There is NO data showing a brush change had no effect. Yet folks refuse to believe the data that has been collected. Instead you make several undocumented assumptions:

1. That your motor is already 85% efficient. Try more like 75%. Add 18% and you get up to 88%. Not bad. My motor is putting out WAY too much heat to be anywhere close to 85% efficient. Personally I am not very impressed. at all. In fact it is lame.

2. That 13% of 20hp could not POSSIBLY be released as heat. That is only 2.6 hp. I am not going to bother putting all the math on here, but that is entirely possible. Remember that heat moves FASTER the bigger the heat differential. So if I am getting 250f on a 60f day that is a 190F heat differential which is A LOT. Now we are probably only using about 16hp which would be about 2hp in heat. Again, completely possible if you bother to do the math. (please remember the comm is copper which moves heat very fast).

3. That Jenifer Aniston wouldn't marry a fine fellow like yourself. Step 1, you have to BELIEVE. Step 2, well, good luck anyway... :rolleyes:

Cheers
 
#13 ·
The brushes definitely seem to raise efficiency. What would be really interesting is if someone with a dyno could do it at several different voltages and power levels between the standard forklift brush and the helwig's. Is the gain linear or non-linear (and in which direction) with higher power/load levels. From what I've seen and read the brush compound is a more efficient conductor and the split/dampened design provides more consistent contact with the commutator.
 
#16 ·
What would you look for? IIRC, higher resistance brushes are used for higher current applications. The carbon composite has a resistance inversely proportional to temperature. As the temp increases... the resistance drops. Pretty kewl huh?
 
#18 ·
I wonder how many of the folks here have power meters on their EVs? Putting one on mine really helped me see how much power I was using for various activities. It also showed how much power I was losing in my LA batteries. I'll expect that if these brushes help out, I'll see it on my power readings.
Do you know if Helwig will pre-radius the brushes for the 8" motors? I saw that on Jack's EVTV store.
 
#20 ·
It should be obvious as to why the use of Helwig brushes have a gain in efficiency for DC motors. It is because of less brush bounce or none at all. Brush bounce is when the brush contact to the commutator is not complete because of the brush moving in which some of the brush surface area or none of it (very bad!!!) is not touching the commutator surface. This results in an increase in electrical resistance, more voltage drop which reduces motor speed, and more heat.
 
#21 ·
I have several exceptions to conclusions drawn from that test but that is another subject. I was looking at going with the split-tops a while back for my ADC-FB4001 because I wanted to go to the higher voltage levels. One thing to keep in mind that the warp 9 doesn't just have the better brushes it also has a better brush holders. On my 9" ADC, the brushes are perpendicular to the comm but the Warp is angled, presumably to increase contact area and better brush wear. The point is, would just changing the brushes alone on a ADC will get you the same advantages as a brush upgrade on a W9?
 
#22 ·
KM,
There are 2 ADC 9s in our club, have you seen a group buy, want to start one?
I emailed Jack and the W9 brushes are not compatible with the FB4001 brushes.

Did you watch the split brush video. It looks like the 1/2 width brush rubbing across the the commutator reduces the vertical movement when going from bar to bar. Also the dual bars with the rubber top seem to act like shock absorbers.
 
#23 ·
I am interested in the 9" brush group buy but would like to hear from some the motor experts. I have no doubt that the red tops are a superior brush but when I contacted helwig back in feb. the first question was if I want to upgrade the brush holder. My plan has been to drive the ADC for now and then upgrade to a W9 (or something else) this winter but if just a brush upgrade gets me what I want...
 
#24 · (Edited)
I have talked with Hellwig extensively about brushes and the brush holder.

They say that a certain amount of force is required for optimal brush contact. The stock springs do a fraction of this. If you crank up the springs then the whole brush holder begins to deform and bend. Also, the brush holder shifts around as motor temperature changes. They are not impressed.

Conveniently, they sell a replacement brush holder that solves these issues. Unfortunately, it is crazy expensive.

There is very little difference between the ADC 9" and Warp 9". Definitely not enough to warrant a swap (edit: I was told this, but who really knows until somebody tries it..). The best value is to just upgrade the brushes using the stock holder and springs.

Cheers:)
 
#25 ·
I have talked with Hellwig extensively about brushes and the brush holder.

They say that a certain amount of force is required for optimal brush contact. The stock springs do a fraction of this. If you crank up the springs then the whole brush holder begins to deform and bend. Also, the brush holder shifts around as motor temperature changes. They are not impressed.

Conveniently, they sell a replacement brush holder that solves these issues. Unfortunately, it is crazy expensive.

There is very little difference between the ADC 9" and Warp 9". Definitely not enough to warrant a swap. The best value is to just upgrade the brushes using the stock holder and springs.

Cheers:)
Thanks for the input. I had been talking with Terry and the holder price scared me off from that idea too. I wonder if you did really want to upgrade the holder you could try to fit a W9 holder and brushes in to the ADC? The W9 has other upgrades such as the higher flow fan but that also be assisted with an separate blower.

When and how much for the 9" group buy?
 
#30 ·
You are correct. I thought about going through evalbum and contacting the 8" motor owners, but it just wasn't worth the time for another couple bucks off. As is, we saved about 45% and will pay about $100 less than those who buy from Netgain or EVtv. Well worth the small effort to work together.

If EV builders all banded together we could get crazy deals on every component. Unfortunately, the cooperative spirit is not nurtured in a cut-throat capitalist society.

Cheers
 
#31 ·
I would also be interested in a 9 inch group buy. I was quoted $211.20 for 8 split top H60 brushes in May so the price is similar to the brushes for the 8 inch. The size is also similar. Ruckus in his first post set the size for the 8 inch ADC at Length:1-5/16" (1.30"), Width:31/32" (.967"), Thick: 5/8" (.625"). Helwig in their quote put the size of the 9 inch ADC brushes at .625 X .966 X 1.25.
 
#32 ·
Hello,
Sounds like they use the same size brush. You are welcome to join in the group purchase. We are paying just over half your quoted price.

However, please note if the brushes are radiused for 8" then there will be a longer break-in period before they fit the 9" comm.

I would perhaps suggest starting a 9" group buy thread and getting a quote from Helwig. I know there are several other ADC 9" owners out there who want to upgrade.

Cheers,
Marcus
 
#33 ·
Hello,
Sounds like they use the same size brush. You are welcome to join in the group purchase. We are paying just over half your quoted price.

However, please note if the brushes are radiused for 8" then there will be a longer break-in period before they fit the 9" comm.

I would perhaps suggest starting a 9" group buy thread and getting a quote from Helwig. I know there are several other ADC 9" owners out there who want to upgrade.

Cheers,
Marcus
If it's not too late would be down for a set. Does anyone know if the Warp 8" and ADC 8" share the same brush size? I can't imagine they would be different. Anyway, I have two Warp 9s in the shop they would fit into eventually after about a week or two of burn in;)

As for how well they work, I watched the whole EVTV segment, and even if its half the efficiency gained under load vs. what Jack got with 12v no load in controlled conditions, it's worth the money. Hell regualrly drop $450 on LRR tires and hope to get 2-3%. This is a no brainer. Thanks for putting it together.
 
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