RCCrawler Forums

zachery023 · 02-19-2011, 01:20 PM

I have had my crawler now for about 3 years and have made numorous upgrades. I currently have a rooster crawler ESC and a NIMH 7.2volt battery pack but it seems like i only get about 5 maybe 6 min of run time on one charge. I have 4 wheel steer so i know that will reduce my run time but it seems like that is still a very short run time on one charge. I just baught a new battery pack but it is still the same story. Any suggestions would help.

Charlie-III · 02-19-2011, 02:10 PM

Since you seem to have the same issue with 2 different packs, it may be an issue with your rig.
Check that the gear meshes are good, no binding in the axles, etc.
How are your motors? Have they had any maintenance (through cleaning, turn comm's, new brushes, oiled bushings/bearings)?

You are running ~ the equal to a 2S LiPo, I would expect you would get more run time than reported.

Narly1 · 02-19-2011, 03:48 PM

Please describe your charging method. How do you ensure that you are fully charging your packs?

Narly1

Charlie-III · 02-19-2011, 04:45 PM

Quote:

Originally Posted by Narly1

Please describe your charging method. How do you ensure that you are fully charging your packs?

Narly1

+1.

Also, what charger are you using?

zachery023 · 02-19-2011, 09:50 PM

I use a Duratrax DC Peak Charger i use mainly a Trickle charge because i have heard that using the fast charge can diminish the life of your battery pack. as far as the rig goes i have been through the entire thing and i clean and oil just about every moving part on it everytime i take it to the rocks.. I am using a axial 27t motor 540. i use a metal spur gear i have checked all of the teeth and they check out ok. i am using a tamiya style plug...

zachery023 · 02-19-2011, 09:52 PM

Quote:

Originally Posted by zachery023

I use a Duratrax DC Peak Charger i use mainly a Trickle charge because i have heard that using the fast charge can diminish the life of your battery pack. as far as the rig goes i have been through the entire thing and i clean and oil just about every moving part on it everytime i take it to the rocks.. I am using a axial 27t motor 540. i use a metal spur gear i have checked all of the teeth and they check out ok. i am using a tamiya style plug...

I normally let trickle charge for about 8 Hours is that to long not long enough..

Duuuuuuuude · 02-19-2011, 09:56 PM

Tamiya plugs will lose their ability to make good connections over time, resulting in a loss of power and crummy run times. The very first thing I would do it cut them off and replace them with Deans.

Next, if you loosen and move the motor away from the spur, does your drivetrain spin smoothly and freely? If not, that is a problem too.

You say the teeth on the gears are good, but is the mesh too tight? There should be just a tiny bit of play between the spur and pinion.

How old is the motor? You can clean and lube it all day long, but if the comm or brushes are worn, it won't do a bit of good.

I still run nimh packs in my Slash, and when I notice they aren't holding a charge like they should, I'll drain them down completely before recharging. I've got a string of light bulbs that I clip on to draw the batteries down.

killswitch · 02-19-2011, 10:24 PM

I dont care what anyone says about Nimh not having memory and not having to care for them. If you use them, you should follow the same charge/discharge/maintenance cycle every time you run. Dont trickle charge either. You should be charging at around 5 amps. The trick to using them is paying attention to the details. Use the same charge current every time. Discharge to .9v/cell before you recharge. Buy a quality charger too. You really want to be able to select what the peak detection is. I tend to use .3-.5v/ cell depending on the pack (based on pack temps during their initial cycles). Find an old carpet racer in your area... they can tell you how to get every bit of performance and life out of your batteries and may have a really good Nimh charger they'd let go for cheap.

Charlie-III · 02-20-2011, 08:42 AM

Killswitch & Duuuuude pretty much covered it. Short term fix on the Tamiya connector is to gently squeeze the barrel part down a bit so it's a tight fit. When you run the rig, check the connector, it should NOT get warm let alone hot.
I also agree on using a higher charge rate, I still run really old purple Sub-C NiCads and they do fine. They sorta like getting warm during charge, but NOT hot.

Most of my RC's still run either NiCad or NiMH, only my crawler has a LiPo.

Wasp26Jim · 02-20-2011, 08:50 AM

What mah mimh batteries are you running? I've always charged my nimh at 1c and had decent results, I think trickle charging all the time would make for a tired battery over time. also make sure your esc is not set for lipo cutoff because this would shut your rig down early.

zachery023 · 02-20-2011, 10:30 AM

thank you everyone you have helped me quite a bit now to put some of these things to use.

Charlie-III · 02-20-2011, 12:07 PM

zach....please make sure you update this thread.....this may help the next guy with the same issue.

killswitch · 02-20-2011, 01:26 PM

Any Nimh cells after the first few batches of OG 3000 panasonics and sanyos (and if you are still using these you should stop and get into the year 2000) should be charged at higher charge rates and be warm near the end of the charge cycle. The IB/IP and elite cells really liked 5-6 amp charge rates. The newer Nimh cells will perform better on the 2nd or 3rd cycle during the same day too, so that's something to consider too.

Get rid of the tamiya plugs now before they cause serious issues down the line. You will over tax the amperage they can handle and they will meltdown, possibly taking your battery and esc with it. Ive even seen tamiya plugs fail while charging and take a charger and power supply with them.

zachery023 · 04-15-2011, 06:41 PM

Sorry it has been so long since i have been on but i have been really busy with work. Just thought i would update you since my last update i have bought a new charger and started charging the batterys the right way and have been getting a lot more run times with my batterys. I have also upgraded my esc to a Novak Goat 3S and a brushless motor. I have also started using lipo batterys and i have noticed a lot more run times and torque. Thank you for all the help this has been a very helpful forum. and again thank you all.
Zach

Charlie-III · 04-16-2011, 07:51 AM

Zach, thanks for the update. Did you get rid of the Tamiya connectors yet??

Glad things are working out for you.

zachery023 · 04-16-2011, 10:43 AM

Quote:

Originally Posted by Charlie-III

Zach, thanks for the update. Did you get rid of the Tamiya connectors yet??

Glad things are working out for you.

Oh ya the Tamiya connectors are long gone that was one of the first things to go.

02-19-2011, 01:20 PM	#1
zachery023 Newbie Join Date: Feb 2011 Location: Lakeville Posts: 10	Question about battery Life I have had my crawler now for about 3 years and have made numorous upgrades. I currently have a rooster crawler ESC and a NIMH 7.2volt battery pack but it seems like i only get about 5 maybe 6 min of run time on one charge. I have 4 wheel steer so i know that will reduce my run time but it seems like that is still a very short run time on one charge. I just baught a new battery pack but it is still the same story. Any suggestions would help.

02-19-2011, 09:56 PM	#7
Duuuuuuuude Suck it up! Join Date: Mar 2008 Location: Arkansas Posts: 11,652	Tamiya plugs will lose their ability to make good connections over time, resulting in a loss of power and crummy run times. The very first thing I would do it cut them off and replace them with Deans. Next, if you loosen and move the motor away from the spur, does your drivetrain spin smoothly and freely? If not, that is a problem too. You say the teeth on the gears are good, but is the mesh too tight? There should be just a tiny bit of play between the spur and pinion. How old is the motor? You can clean and lube it all day long, but if the comm or brushes are worn, it won't do a bit of good. I still run nimh packs in my Slash, and when I notice they aren't holding a charge like they should, I'll drain them down completely before recharging. I've got a string of light bulbs that I clip on to draw the batteries down. Last edited by Duuuuuuuude; 02-19-2011 at 10:00 PM.

02-20-2011, 10:30 AM	#11
zachery023 Newbie Join Date: Feb 2011 Location: Lakeville Posts: 10	Thanks thank you everyone you have helped me quite a bit now to put some of these things to use.

04-15-2011, 06:41 PM	#14
zachery023 Newbie Join Date: Feb 2011 Location: Lakeville Posts: 10	Update Sorry it has been so long since i have been on but i have been really busy with work. Just thought i would update you since my last update i have bought a new charger and started charging the batterys the right way and have been getting a lot more run times with my batterys. I have also upgraded my esc to a Novak Goat 3S and a brushless motor. I have also started using lipo batterys and i have noticed a lot more run times and torque. Thank you for all the help this has been a very helpful forum. and again thank you all. Zach

02-19-2011, 02:10 PM	#2
Charlie-III I wanna be Dave Join Date: Nov 2010 Location: 07456 N. NJ USofA Posts: 8,314	Since you seem to have the same issue with 2 different packs, it may be an issue with your rig. Check that the gear meshes are good, no binding in the axles, etc. How are your motors? Have they had any maintenance (through cleaning, turn comm's, new brushes, oiled bushings/bearings)? You are running ~ the equal to a 2S LiPo, I would expect you would get more run time than reported.

02-19-2011, 03:48 PM	#3
Narly1 Quarry Creeper Join Date: Jul 2008 Location: Erin, Ontario, CANADA Posts: 471	Please describe your charging method. How do you ensure that you are fully charging your packs? Narly1

02-19-2011, 09:50 PM	#5
zachery023 Newbie Join Date: Feb 2011 Location: Lakeville Posts: 10	I use a Duratrax DC Peak Charger i use mainly a Trickle charge because i have heard that using the fast charge can diminish the life of your battery pack. as far as the rig goes i have been through the entire thing and i clean and oil just about every moving part on it everytime i take it to the rocks.. I am using a axial 27t motor 540. i use a metal spur gear i have checked all of the teeth and they check out ok. i am using a tamiya style plug...

02-19-2011, 10:24 PM	#8
killswitch RCC Addict Join Date: Jun 2005 Location: St. Albans Posts: 1,441	I dont care what anyone says about Nimh not having memory and not having to care for them. If you use them, you should follow the same charge/discharge/maintenance cycle every time you run. Dont trickle charge either. You should be charging at around 5 amps. The trick to using them is paying attention to the details. Use the same charge current every time. Discharge to .9v/cell before you recharge. Buy a quality charger too. You really want to be able to select what the peak detection is. I tend to use .3-.5v/ cell depending on the pack (based on pack temps during their initial cycles). Find an old carpet racer in your area... they can tell you how to get every bit of performance and life out of your batteries and may have a really good Nimh charger they'd let go for cheap.

02-20-2011, 08:42 AM	#9
Charlie-III I wanna be Dave Join Date: Nov 2010 Location: 07456 N. NJ USofA Posts: 8,314	Killswitch & Duuuuude pretty much covered it. Short term fix on the Tamiya connector is to gently squeeze the barrel part down a bit so it's a tight fit. When you run the rig, check the connector, it should NOT get warm let alone hot. I also agree on using a higher charge rate, I still run really old purple Sub-C NiCads and they do fine. They sorta like getting warm during charge, but NOT hot. Most of my RC's still run either NiCad or NiMH, only my crawler has a LiPo.

02-20-2011, 08:50 AM	#10
Wasp26Jim Quarry Creeper Join Date: Sep 2010 Location: Central MN H-Town Posts: 291	What mah mimh batteries are you running? I've always charged my nimh at 1c and had decent results, I think trickle charging all the time would make for a tired battery over time. also make sure your esc is not set for lipo cutoff because this would shut your rig down early.

02-20-2011, 12:07 PM	#12
Charlie-III I wanna be Dave Join Date: Nov 2010 Location: 07456 N. NJ USofA Posts: 8,314	zach....please make sure you update this thread.....this may help the next guy with the same issue.

02-20-2011, 01:26 PM	#13
killswitch RCC Addict Join Date: Jun 2005 Location: St. Albans Posts: 1,441	Any Nimh cells after the first few batches of OG 3000 panasonics and sanyos (and if you are still using these you should stop and get into the year 2000) should be charged at higher charge rates and be warm near the end of the charge cycle. The IB/IP and elite cells really liked 5-6 amp charge rates. The newer Nimh cells will perform better on the 2nd or 3rd cycle during the same day too, so that's something to consider too. Get rid of the tamiya plugs now before they cause serious issues down the line. You will over tax the amperage they can handle and they will meltdown, possibly taking your battery and esc with it. Ive even seen tamiya plugs fail while charging and take a charger and power supply with them.

04-16-2011, 07:51 AM	#15
Charlie-III I wanna be Dave Join Date: Nov 2010 Location: 07456 N. NJ USofA Posts: 8,314	Zach, thanks for the update. Did you get rid of the Tamiya connectors yet?? Glad things are working out for you.

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