3LikesTekin RX8 1/8 Scale Brushless ESC Thread
09-18-2009, 10:43 PM
#4471
09-19-2009, 03:10 AM
#4472
Ahahahaha 
The potential for a ROAR lipo tangent is great, but I digress......
The potential for a ROAR lipo tangent is great, but I digress......
09-19-2009, 06:14 AM
#4473
No it was an expensive pack because it said roar 
(ie not a zippy)..
I have had two fail because of parts falling off the bottom of the board.
The last one had one of the chips (bec inverter?) floating around the bottom of the esc.I would assume it happened again and this time shorted out a part in the pcb.I was not planning on letting everyone know that parts were just falling off the bottom of my boards but I guess I need to put it out there now.
I have not taken it apart yet as I would like to take some pics today to both show that I know how to solder and to show how well it is protected.I would also like to give Tekin a call before I open it up as not to void any warranty I have.
There is another racer at our track that lost one too. There are plenty of people posting here with problems. I am not buying the "it's me" thing..
There is/was a problem with the manufacturing/soldering process.
Again I have broken the other esc's on other packs. This pack was just about brand new. It only had a little over a weekend of racing on it.
(ie not a zippy)..I have had two fail because of parts falling off the bottom of the board.
The last one had one of the chips (bec inverter?) floating around the bottom of the esc.I would assume it happened again and this time shorted out a part in the pcb.I was not planning on letting everyone know that parts were just falling off the bottom of my boards but I guess I need to put it out there now.
I have not taken it apart yet as I would like to take some pics today to both show that I know how to solder and to show how well it is protected.I would also like to give Tekin a call before I open it up as not to void any warranty I have.
There is another racer at our track that lost one too. There are plenty of people posting here with problems. I am not buying the "it's me" thing..
There is/was a problem with the manufacturing/soldering process.
Again I have broken the other esc's on other packs. This pack was just about brand new. It only had a little over a weekend of racing on it.
09-19-2009, 07:30 AM
#4476
Hey ESC makers !!!
I fully understand the tough conditions ESC's are used under but that said, they still can be made to be more reliable. Just based on the number threads regarding the issue there is still an obvious problem. I've had failures myself.
I have 30+ years background in electronic device design and manufacture for everything from cell phones to missile guidance systems to tank control systems and based on that experience I can say with all certainty that there is A LOT of things you guys can do to make your ESC units more robust and reliable. Of course many of these things come at a cost but some are pretty nominal. The items below are in order of manufacturing cost impact. A little free consulting service.....
1. Components falling off a PCB should NEVER happen. That is just poor workmanship from your subcon. Kick their ass and make sure they are ISO certified and follow standard best practices.
2. Use either OSP, Ag, or HASL for the PCB surface finish. Do not use Ni/Au surface finish as this results in a less robust solder joint.
3. PCB design can be key as it relates to long term mechanical shock resistance. Component placement, through hole vias, internal Cu lands, use of micro vias, Cu plating thickness, etc. all can be used to make a more robust soldering platform.
4. Use a conformal coating over the finished PCB. This keeps moisture out and adds significant mechanical shock resistance to the solder joints.
5. Use a PCB substrate that is thermally conductive and glass rich for rigidity. There are literally hundreds of glass/resin combinations you could use.
6. Tie the stacked PCBs together in the center using soldered "posts" so there is less flex of the PCB. Don't rely just on edge mounting.
6. If you REALLY want to go for it, use a metal core PCB that utilizes an Al, or Cu core. This is super rigid, super thermally conductive, but also fairly expensive.
My 2.5 cents.....
I fully understand the tough conditions ESC's are used under but that said, they still can be made to be more reliable. Just based on the number threads regarding the issue there is still an obvious problem. I've had failures myself.
I have 30+ years background in electronic device design and manufacture for everything from cell phones to missile guidance systems to tank control systems and based on that experience I can say with all certainty that there is A LOT of things you guys can do to make your ESC units more robust and reliable. Of course many of these things come at a cost but some are pretty nominal. The items below are in order of manufacturing cost impact. A little free consulting service.....
1. Components falling off a PCB should NEVER happen. That is just poor workmanship from your subcon. Kick their ass and make sure they are ISO certified and follow standard best practices.
2. Use either OSP, Ag, or HASL for the PCB surface finish. Do not use Ni/Au surface finish as this results in a less robust solder joint.
3. PCB design can be key as it relates to long term mechanical shock resistance. Component placement, through hole vias, internal Cu lands, use of micro vias, Cu plating thickness, etc. all can be used to make a more robust soldering platform.
4. Use a conformal coating over the finished PCB. This keeps moisture out and adds significant mechanical shock resistance to the solder joints.
5. Use a PCB substrate that is thermally conductive and glass rich for rigidity. There are literally hundreds of glass/resin combinations you could use.
6. Tie the stacked PCBs together in the center using soldered "posts" so there is less flex of the PCB. Don't rely just on edge mounting.
6. If you REALLY want to go for it, use a metal core PCB that utilizes an Al, or Cu core. This is super rigid, super thermally conductive, but also fairly expensive.
My 2.5 cents.....
09-19-2009, 08:21 AM
#4477
Hey ESC makers !!!
I fully understand the tough conditions ESC's are used under but that said, they still can be made to be more reliable. Just based on the number threads regarding the issue there is still an obvious problem. I've had failures myself.
I have 30+ years background in electronic device design and manufacture for everything from cell phones to missile guidance systems to tank control systems and based on that experience I can say with all certainty that there is A LOT of things you guys can do to make your ESC units more robust and reliable. Of course many of these things come at a cost but some are pretty nominal. The items below are in order of manufacturing cost impact. A little free consulting service.....
1. Components falling off a PCB should NEVER happen. That is just poor workmanship from your subcon. Kick their ass and make sure they are ISO certified and follow standard best practices.
2. Use either OSP, Ag, or HASL for the PCB surface finish. Do not use Ni/Au surface finish as this results in a less robust solder joint.
3. PCB design can be key as it relates to long term mechanical shock resistance. Component placement, through hole vias, internal Cu lands, use of micro vias, Cu plating thickness, etc. all can be used to make a more robust soldering platform.
4. Use a conformal coating over the finished PCB. This keeps moisture out and adds significant mechanical shock resistance to the solder joints.
5. Use a PCB substrate that is thermally conductive and glass rich for rigidity. There are literally hundreds of glass/resin combinations you could use.
6. Tie the stacked PCBs together in the center using soldered "posts" so there is less flex of the PCB. Don't rely just on edge mounting.
6. If you REALLY want to go for it, use a metal core PCB that utilizes an Al, or Cu core. This is super rigid, super thermally conductive, but also fairly expensive.
My 2.5 cents.....
I fully understand the tough conditions ESC's are used under but that said, they still can be made to be more reliable. Just based on the number threads regarding the issue there is still an obvious problem. I've had failures myself.
I have 30+ years background in electronic device design and manufacture for everything from cell phones to missile guidance systems to tank control systems and based on that experience I can say with all certainty that there is A LOT of things you guys can do to make your ESC units more robust and reliable. Of course many of these things come at a cost but some are pretty nominal. The items below are in order of manufacturing cost impact. A little free consulting service.....
1. Components falling off a PCB should NEVER happen. That is just poor workmanship from your subcon. Kick their ass and make sure they are ISO certified and follow standard best practices.
2. Use either OSP, Ag, or HASL for the PCB surface finish. Do not use Ni/Au surface finish as this results in a less robust solder joint.
3. PCB design can be key as it relates to long term mechanical shock resistance. Component placement, through hole vias, internal Cu lands, use of micro vias, Cu plating thickness, etc. all can be used to make a more robust soldering platform.
4. Use a conformal coating over the finished PCB. This keeps moisture out and adds significant mechanical shock resistance to the solder joints.
5. Use a PCB substrate that is thermally conductive and glass rich for rigidity. There are literally hundreds of glass/resin combinations you could use.
6. Tie the stacked PCBs together in the center using soldered "posts" so there is less flex of the PCB. Don't rely just on edge mounting.
6. If you REALLY want to go for it, use a metal core PCB that utilizes an Al, or Cu core. This is super rigid, super thermally conductive, but also fairly expensive.
My 2.5 cents.....
) but I too wondered if potting or encapsulating at least the bottom PCB board wouldn't help the loose component problem. I had the 'all LEDs on, no drive' problem two weeks ago and Tekin walked me thru the things to check and resolder, and now that I have it fixed I am considering encapsulating the bottom board. Clearly this would void any future warranty, but being a curious and adventurous guy I may do it anyway, since I am comfortable that my ESC is now soldered correctly. If nothing else, it might help with future dirt, moisture, shock issues. While allowing the ESC to float in its mounting a bit is a help, I also want the boards themselves to be bulletproof. My 1.5 cents....
09-19-2009, 10:34 AM
#4479
I was at the track with J.D.roost when his ESC went up ... i have also been there every single time the other 2 or 3 he had died. Jim always has the fastest and cleanest cars on the track. I have been going to school for 3 years to be an electronic technician and his soldering is right there with mine if not better.. I would never blame this problem on "User Error". There is nothing wrong with J.D.roosts soldering/electronics, even his batteries are top of the line. I have looked over his car and there is nothing physically wrong with it other then the smoking ESC and puffed packs. He even had like 2 inches or gel used to mount gyros on helis all around the ESC. There is a serious problem with the Tekin systems. Like i said there is no way there is "User Error" in this case ... Jim has been in the hobby and racing longer then i have been alive and he does not make stupid mistakes like bad solder joints and reversing polarity. This problem happened in the middle of the second heat out of no where and his car just smoked up. There is no reason for this problem... I myself have a tekin system and after Jims problems i am very unhappy i bought this system. Just the thought my 300+ dollar system and my 250+ in batteries can just go poof in the middle of the race with no driver fault really makes me sick to my stomach.
-Jim i hope tekin works out the problem for you and im sorry you had to run NIRTO again in the main !
-Jim i hope tekin works out the problem for you and im sorry you had to run NIRTO again in the main !
Last edited by stew215; 09-19-2009 at 11:15 AM.
09-19-2009, 11:55 AM
#4480
i too am very disappointed with tekins reliability record with this rx8 system, when it works it works great but its just so fragile
09-19-2009, 12:09 PM
#4481
Both of mine are still working awesome! I had heating issues in the truck, but since I've done fan mods and switched to one 4s pack instead of two 2s packs they have ran flawlessly. I pounded the crap out of the RC8T today at the track with no issues. I know, I know... knock on wood, but still currently a satisfied Tekin customer!
DJ
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DJ
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09-19-2009, 06:07 PM
#4482
http://www.youtube.com/watch?v=pm0HxpxNWO0
here is a video that was taken today that happened to include my tekin cutting out on me. This is a repaired unit that I just recieved back and i went out today to run it. I had run 8 packs (15 min runs) prior to this happening. When it did happen i picked it up turned it off and back on and it worked again. It did it again about 2 laps later before the take off of that same double and same thing. Then i ran another 2 packs to finish the day off with no problems. What could be causeing the problem of that cut out. Its not thermaling or hitting voltage cutoff. any sugestions on what to check ?
here is a video that was taken today that happened to include my tekin cutting out on me. This is a repaired unit that I just recieved back and i went out today to run it. I had run 8 packs (15 min runs) prior to this happening. When it did happen i picked it up turned it off and back on and it worked again. It did it again about 2 laps later before the take off of that same double and same thing. Then i ran another 2 packs to finish the day off with no problems. What could be causeing the problem of that cut out. Its not thermaling or hitting voltage cutoff. any sugestions on what to check ?
09-19-2009, 06:13 PM
#4483
What packs do you use? What type of power connector are you running? Deans?
That is a bit off since it's working right after the fact for 2 packs on.
This sounds like a loose connection somewhere. When it happened did the car have steering? What receiver/radio?
That is a bit off since it's working right after the fact for 2 packs on.
This sounds like a loose connection somewhere. When it happened did the car have steering? What receiver/radio?
09-19-2009, 06:24 PM
#4484
