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  #271   Spotlight this post!  
Unread 23-01-2012, 23:56
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by Karthik View Post
Order #7163022

All motors showed a large resistance (over 4 M ohms) between the terminals and the case. This is the same symptom we saw from our motors last year. Our order numbers from last year were: 7151274, 7150067 and 7145378.



Chastising your customers in a public forum for complaining about defective products that you supplied? That's an interesting brand of customer service to say the least. In general the FIRST community are one of the most forgiving population samples that you'll ever find. The fact that there's been this much outcry about your products and customer service from a group that's normally very tolerant should absolutely leave an impression upon you.
Some people here actually defending other banebots products like the 550's and the P60 transmissions. Frankly, that's a testimate to how forgiving this community is. We saw 50% failure on our 775 motors last year. Some shafts were locked up coming out of the box. Some good ones later developed case shorts. Yet we still bought some products from banebots this year, though we'll never buy a 775 again (we even had one fail during championship inspection).
  #272   Spotlight this post!  
Unread 24-01-2012, 00:09
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by banebots View Post

As for some of the other stuff in this thread and on this forum in general, I'm not sure what to think. At a minimum it makes me question our continued support of FIRST. I'd ask that folks step back and read some of what is being posted from an objective view point and consider what kind of impression it leaves not only on BaneBots but on this forum and FIRST.
Chief Delphi is not the FIRST majority, take the generalizations here with a grain of salt.

As other have stated, we very gladly support purchasing of 500 series motors as well as P60 gearboxes and Banebots wheels - all of which I just put in an order for worth around $200.
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Unread 24-01-2012, 00:10
Andrew Schreiber Andrew Schreiber is offline
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by banebots View Post
We are a bit confused by the constant stream of BaneBots bashing on this forum.
I'm not one of the teams you asked about but I am from a team who had a very negative experience with your company last year.

Last year I was the lead mentor on a team. Now, we didn't have many design resources and our work was slow, we didn't figure out what sort of transmission we needed for our arm until around week 3. We placed an order for the ones for our arm as well as the ones for our roller claw. We waited, and when we found out that the parts likely wouldn't be arriving until after the end of build season we were forced to make drastic changes.

Now, I understand that supply issues happen. But I would have expected that Banebots, as a supplier to FIRST for many years, would have been able to predict demand better than they appeared to. When nearly half the motors in our kit are from your product line and you make the easiest to interface gearboxes it is pretty safe to assume that many teams will be ordering from you.

And ultimately none of this really matters because it isn't you who has to tell a student that we can't build their design because the parts took 2/3 of our build season to ship. That's why I have a sour taste in my mouth for Banebots. I think they make competitive products at a fair price. I plan on using them in some of my projects. But I cannot count on them to ship in a reasonable time frame because they lost my trust.

I hope this explains to you my negative experience, if it doesn't I would be more than willing to talk with you in private about it. I hope that next year at this time we are all praising BB because I really do think they make some good products.
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Unread 24-01-2012, 00:19
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Re: Banebots RS-775 Case Short

Having had major issues with the 775's last year, our team plans to use the 550's this year. They are a quality product, along with the gearboxes that banebots offers (provided you do not exceed the torque limitations on the gearboxes). We are slightly disappointed that we can't really expect to see our order any sooner than 2-3 weeks after it is placed, but we planned accordingly and have ordered in enough time so that we will get what we need.

As for the 775's I can't quite understand why they are still on the market. It seems as though there is something that causes these motors to short to the case consistently. So rather than throwing out the half that are shorted and shipping off the ones that are "okay" as per quality control, why aren't they looking to freeze the product line, improve the manufacturing process so there are no more shorts, and then roll out the product again when/if the short issue is fixed? These things don't just happen for no reason...there has to be a root cause of the shorting issue and it MUST be something that can be fixed. Do what engineers do and SOLVE THE PROBLEM. We thank you for your support banebots, but we resent your one faulty product that happens to be a valuable commodity in our competition.
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  #275   Spotlight this post!  
Unread 24-01-2012, 00:20
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by banebots View Post
As for some of the other stuff in this thread and on this forum in general, I'm not sure what to think. At a minimum it makes me question our continued support of FIRST. I'd ask that folks step back and read some of what is being posted from an objective view point and consider what kind of impression it leaves not only on BaneBots but on this forum and FIRST.
I'll go ahead and stand up for them here. They offer a decent quality product at a fair price. Through family, I know what it's like to be a small company, and it isn't easy. Our 775 motor last year performed flawlessly and still does. Our 256:1 P60 on that motor wrecked its teeth, even with good grease, the steel ring gear, and the shaft very well supported, but we were exceeding the specified maximum torque with shock loads. We had zero problems with 64:1 and 16:1 P60s with 550s.

Banebots makes very useful products at really a very affordable price for what they are. There really is no competitor producing many of the products they do. The wheels are fantastic for certain applications.

Having come from FIRST way back in the stone ages when cordless drill motors/gearboxes and Skyway Wheels were the only game in town, I'm VERY glad BaneBots continues to support us.

Can the company improve a few flaws? Sure. Should we bash them so much on a forum to the extent they question their support for our whole program? No.

If you think you can do a better job than Banebots, you go try starting a company that produces and sells those same things and we'll see how that works out.
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  #276   Spotlight this post!  
Unread 24-01-2012, 00:43
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by banebots View Post

Given the number of RS-775 motors shipped since implementing the 100% testing practice and the very low reported number of problems we believed our testing adequate. It should be noted that no attempt is made to fix any motor that fails testing - failures are removed from product inventory and isolated where they can not be accidentally mixed in with tested product. It would appear from posts in this thread that we may need to review parts of this process. We would ask for a bit of help from teams that have made posts about recent failures with RS-775s. We are particularly interested in posts by the following teams:

Team 1114 (post 224)
Team 1323 (post 231)
We have not contacted Banebots due to a few reasons:

A) We are darn happy with the p60 4:1 gearbox, literally we are using them all over the place.

B) We did not actually place the order, but if Adam (FRC973) has it please put it up. We put a bulk order in with 973 last year. Our issues happened after season even tho 973's happened during.

I am not remotely trying to be rude, but here's a perspective from our team:

In 2007 we used banebot gearboxes, we went through around 20-30 and even though we weren't remotely good that year. We still could not drive around. We found that a ton of teams were killing those gearboxes.

We bought the generation of gearboxes before the p60's and had issues with those. So we stopped using them in 08.

In 2009 we took another shot at them, we had the gears pretty much turn to dust as the gearbox on our intake exploded 4-5 times. Yes properly greased and well kept/mounted and the shaft was supported.

2010 we didn't bother using them.

2011, we took another shot at them and used the low reduction ones as basically an "integrator to fp's and other 550/775 style motors. We were extremely stoked and loved the new p60 line.

2012, we have ordered around 12 p60's and 12 rs 550 motors. Can't wait to get them. As they make our design a lot easier.

Banebots, the real issue, a lot of teams have here is simply that the 775 motor has lost teams a lot of matches and some of the products have been garbage.

We are still using parts from banebots but we've been bitten multiple times. There's only so many times a team will allow it, we as a team have the resources to just cut our own 32DP gears and call it day.

But we are still using banebots this year.

-RC
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  #277   Spotlight this post!  
Unread 24-01-2012, 00:50
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Re: Banebots RS-775 Case Short

I'm constantly guilty of being a wall-rider for many scenarios, and this one is the same. Like I say a lot, both sides are at fault here.

CD community:
I understand that the 775 has not been working recently, and that we're all kinda frustrated about that. However, that doesn't mean that Banebots isn't a good provider. Our 2011 robot, while not too successful, was powered by 4 CIM motors for the drive and a BaneBots 775 for the arm, and not once to this day have we had a problem with it. I know other teams have had a multitude of problems with the 775, and while that is something to be spoken up about, it's not something to create a thread of complaints about. I, for one, wholeheartedly appreciate everything our friends at Banebots do for us. Companies like AndyMark, Banebots, etc. supply FIRST teams, and often work their hardest to ensure that we are getting the best of what they can offer. I'm no business owner, but I can tell you as a fact that companies like Banebots are no walk in the park to operate, especially with the high demands of build season. We are part of FIRST, and as stated before are very understanding people. And while that holds to be true, our reactions sure are not showing the gracious professionalism expected by us from not only our peers, but the world around us. If a problem like this shows up, we as FIRSTers have the duty to not only alert the manufacturer of the product with the problem, but to work with them to engineer a solution to it. We're here to change the world, not hold others back.

Banebots Company:
To start, I really appreciate all of the things you do for FIRST teams and the great products you have distributed for our use. I know the hardships it takes of running a business, and how you probably may feel by reading the comments on this thread. Like I said above, this is both side's problem. Banebots is a great company, and great companies need to know how to handle complaints, whether emailed directly to them, or posted on an online forum. I understand that what has been posted seems like people are "bashing" your RS 775 motor, however as a great company, you should know that this doesn't mean to get mad at the people, but to inquire as to how you can fix your product so the product is not only fixed, but better than it was before. FRC teams do the best in their power to make their robots feats of engineering unmatched by any other program available, and you should be honored to be part of the program. FIRST loves Banebots, and Banebots loves FIRST (Why else would you continue to sell us your products? ) You have always been an invaluable addition to every team's designs since you joined the FIRST family, and we all hope you stay with us to further explore the engineering experiences and opportunities to come.

Thank you to anyone who reads this, and I hope that both the CD community and the Banebots company will be able to engineer their way through this mess and confusion.

-Andrew
  #278   Spotlight this post!  
Unread 24-01-2012, 00:59
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by banebots View Post
We have had conversations with only one customer concerning manufacturing defects with an RS-775 purchased this year and replacements were sent out the same day.

We received those replacements today and I was told they checked out on arrival.


We plan on using 1 or 2 of the 775's for launching the ball to the hoop.
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Unread 24-01-2012, 01:01
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by SuperNerd256 View Post
If a problem like this shows up, we as FIRSTers have the duty to not only alert the manufacturer of the product with the problem, but to work with them to engineer a solution to it. We're here to change the world, not hold others back.
What if FIRST were to release the one rule that tells us which motors are legal and in what quantities well before kickoff (Game Hint)? It wouldn't give us any real advantage in knowing what to design for and all teams would be at an equal advantage. This would hopefully spread out the demand from a six week build season over a longer period of time and not stress our suppliers so much. We wouldn't run into as many problems with product shortages and lead times in the build season. This would be easier on teams and FIRST suppliers. Sure we could've purchased banebots motors and gearboxes before the season started, but we wouldn't KNOW that they would prove useful.
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Unread 24-01-2012, 01:02
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Re: Banebots RS-775 Case Short

With the openness of the current motor rules, they my as well update it for 2013 to any 500 size motor less than X amount of power.
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Unread 24-01-2012, 02:53
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by SuperNerd256 View Post
If a problem like this shows up, we as FIRSTers have the duty to not only alert the manufacturer of the product with the problem, but to work with them to engineer a solution to it.
This. A thousand times this. I can't fix problems I don't know about.
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Unread 24-01-2012, 08:11
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Re: Banebots RS-775 Case Short

As Brad posted our motors arrived today and they tested out good.

We on 222 have been using Banebots for quite some time with little to no issues other then some poor design decisions leading to premature failure. We've used their 540s and 550s many times without a hint of trouble. Heck we even had no trouble with the 775s last season and that's what has lead us to decide on using them again. Banebots produces price friendly useful products. We are a low budget team and maybe that's why we aren't as quick to pass judgement. We don't expect to get a Ferrari When we are buying a Ford. Part of the engineering challenge for small teams like us is to take that Ford and use it for all it's worth.

Good luck to everyone and don't be afraid to call up Banebots if you have any issues. They were very responsive to our issues. Help them help us.
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Unread 24-01-2012, 08:31
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by Karthik View Post
All motors showed a large resistance (over 4 M ohms) between the terminals and the case. This is the same symptom we saw from our motors last year. Our order numbers from last year were: 7151274, 7150067 and 7145378.
Karthik,
Four Megohms between case and either terminal is perfectly acceptable. The failure in last year's motors were zero ohms in the same test. The amount you measured (if in fact in the megohm range) could be moisture in the air or your finger tips. I would expect that the fault condition would be in the zero to 1000 ohm range. The fault, as documented by others, in 2011 motors occurred when one or more windings became shorted to the armature. To fully test motors, it requires that the tester connect one probe to a terminal (it does not matter which) and the other probe to the case while turning the motor several revolutions. If the meter suddenly drops to near zero, then that winding is defective. A digital meter set to the continuity beep position will beep on a bad motor when the short is reached. No beep and the motor is likely good.
On occasion, shorts also occurred with excess solder migrating into areas of the motor that bypassed internal insulation. The measurement/test would give the same results. I believe that some motors would not show the defect until run for a while. I would suggest that teams run the motors prior to any testing.
In response to Banebots, I agree it is unfair at this point to chastise an entire product line for the fault of one product. They are trying to correct a problem encountered by their customers. Give them a chance. As others have found there are other motors in their line that teams are using with confidence.
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Unread 24-01-2012, 10:16
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by Al Skierkiewicz View Post
Karthik,
Four Megohms between case and either terminal is perfectly acceptable. The failure in last year's motors were zero ohms in the same test. The amount you measured (if in fact in the megohm range) could be moisture in the air or your finger tips. I would expect that the fault condition would be in the zero to 1000 ohm range. The fault, as documented by others, in 2011 motors occurred when one or more windings became shorted to the armature. To fully test motors, it requires that the tester connect one probe to a terminal (it does not matter which) and the other probe to the case while turning the motor several revolutions. If the meter suddenly drops to near zero, then that winding is defective. A digital meter set to the continuity beep position will beep on a bad motor when the short is reached. No beep and the motor is likely good.
On occasion, shorts also occurred with excess solder migrating into areas of the motor that bypassed internal insulation. The measurement/test would give the same results. I believe that some motors would not show the defect until run for a while. I would suggest that teams run the motors prior to any testing.
In response to Banebots, I agree it is unfair at this point to chastise an entire product line for the fault of one product. They are trying to correct a problem encountered by their customers. Give them a chance. As others have found there are other motors in their line that teams are using with confidence.
Al, this precise test was run, with the motor displaying failure characteristics. The 775's we received were definitely defective. Also, last year motors that initially tested as good, all failed after use in practice or competition.
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Unread 24-01-2012, 10:23
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Re: Banebots RS-775 Case Short

Quote:
Originally Posted by Karthik View Post
Al, this precise test was run, with the motor displaying failure characteristics. The 775's we received were definitely defective. Also, last year motors that initially tested as good, all failed after use in practice or competition.
We had the same results. Even if we found a motor that checked out as "good", after some period of time running on the robot it would eventually short. Eventually every 775 we used became shorted. We went through about 6 or 7 of them I believe.


One other thing I want to add is in regards to what happened at the beginning of the issues with the 775 last year. While BaneBots is doing the right thing now and standing behind their product, this was not originally the case. If you go back in this thread to around posts #64 & 65, you will see testaments from teams here stating that BaneBots was not taking back their shorted 775 motors. Instead they were advising teams to do the "zap" method to fix them. While this method did usually give the motor a bit of a 2nd life, and they are now publicly stating they are taking them back and providing replacements, this was NOT the original tune sung when the problem first arose.

I am not trying to stir the pot or anything of the sort. Personally, I completely understand why some teams are choosing to not use BB components on their robots. We will be using components from BaneBots that are not 775s, and we certainly appreciate their support. However, our memory is not that short term, so we are cautious in our dealings with their components. We've had success with them in the past, and we've also had close to insurmountable failure.



-Brando
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Last edited by Brandon Holley : 24-01-2012 at 10:32.
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