Go Back   RCCrawler Forums > RCCrawler General Tech > Electronics
Loading

Notices

Thread: ProModeler Servo: 420oz, billet case, o-ringed, $79

Reply
 
LinkBack Thread Tools Display Modes
Old 06-13-2019, 08:01 PM   #641
ROCK STOP HOBBIES
 
CM9000's Avatar
 
Join Date: Feb 2009
Location: Detroit
Posts: 1,971
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

WT, your inner sidewall is separating from the main tread. glue it when you got a sec.

Everybody else, carry on.

Jk. These are crawlers. A hey ok no brainer bec works just fine for servos. You can actually adjust the output voltage to the servo. Also, I've never had a castle bec fail.

Even on planes, I have never heard of using a separate battery to power the servos from the esc's.. Ihave a pop wing that has only 1 spot for a battery.
CM9000 is offline   Reply With Quote
Sponsored Links
Old 06-13-2019, 08:29 PM   #642
I wanna be Dave
 
WHITE-TRASH's Avatar
 
Join Date: Aug 2004
Location: Tri-cities, WA
Posts: 4,464
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by CM9000 View Post
WT, your inner sidewall is separating from the main tread. glue it when you got a sec.


Already fixed, there were a handful of spots coming apart. Prepping the rig for a comp Saturday so all the tires got a once over.
WHITE-TRASH is online now   Reply With Quote
Old 06-13-2019, 08:54 PM   #643
Newbie
 
Join Date: Sep 2018
Posts: 41
Default ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by jbeech View Post
OK, strap a WATT meter to your rig temporary like and go for a crawl. See what the voltage did. And airplane bubble or not, we still come back to the central question, why on Earth do you want a variable voltage supply for your controls? Don't you understand that means variable output from the servo - any servo. What's the fetish of using one pack instead of isolating the pack for control from the pack used for propulsion? A battery costs like $15-20 bucks and supplies the best juice money can buy. Or buy a BEC for more than that and it supplies garbage. I mean I grok why you use a BEC with a toy truck and a child because responsibility for managing two packs may be a bit much, but you guys are men and you definitely aren't running toy trucks. BECs exist for one reason, saving the manufacturer money. They have zero to do with performance. Zip. And variable voltage is nuts for every conceivable reason. It means your servo reacts differently as voltage changes. Why would you desire this? I really, really am perplexed why you'd want inferior performance after spending a lot for superior capability. It's like taking a world class sprinter and forcing him to run whilst carrying a 100lb sack of corn when competing with others not encumbered, e.g. handicapping him. Variable voltage handicaps the servo. Any servo, not just mine. But I remain with an open mind for a performance reason for doing this. What is the reason, having to do with performance, for wanting to operate your controls off a variable voltage source? I mean we bust a nut trying to extract the most possible performance from all the components and package them into our servo and some of you are basically telling me performance isn't important? Now I am really confused. Have you ever looked at the specs chart for our servos. We publish torque and speed for several voltages ranging from 4.8 through 8.4VDC and they mimic that of any other servo on the market. Less voltage means reduced torque output and increased transit time - weaker and slower . . . and this is a good thing?!? Note; this is true for every single servo on the planet. So when the propulsion pack voltage varies, the amount of torque you have available from your servo varies - and - the steering response is slower. Just for a moment imagine driving to work where your cars has less power steering sometimes and more power steering at other times. You'd take it to the dealer to have it repaired! Or perhaps driving it when the brakes are easy to operate sometimes and very hard to operate at other times. This would make for a very difficult car to operate. Same thing with these rigs when the voltage to the servos is varying based on the demand being placed on the battery pack by the propulsion motor. Reflect back on how throttle is applied to your rig. Is it a smooth application of power, or are you on and off the throttle constantly as you find a line and work your way up or down the course? Every time you vary throttle, not to 100% just varying it a little bit means the voltage is varying. Yet we design controls for the most steady source possible so that you get a consistent result. I keep seeking analogies. Imagine riding a bicycle with rubber handle bars so that as you apply torque to steer the bars bend and thus, you can't ever predict what the front wheels will do. That's in effect what some of you are saying you want, variable results.






Lots of words, no data....maybe someone should set up an experiment with a crawler with meters on everything in different configurations to resolve this debate....BTY, I love my Promodeler servos and I run them off castle BECís

Last edited by Discohair; 06-13-2019 at 08:58 PM.
Discohair is offline   Reply With Quote
Old 06-19-2019, 08:09 AM   #644
Pebble Pounder
 
Join Date: Jun 2013
Location: Twin Lake
Posts: 157
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

For me it isn't that I don't want the best performance. For most of my rigs space is limited and trying to find room for another lipo vs tucking a smaller castle 10amp bec is a lot easier. Or even with some of the newer esc with high amp outputs I can even eliminate the external bec. These setups give me more then satisfactory performance, so in the few models I have that I could put a extra pack in I don't because it works good enough for what I do with it.
Druxus is offline   Reply With Quote
Old 06-19-2019, 09:42 AM   #645
RCC Addict
 
Join Date: Nov 2014
Location: Nowhere
Posts: 1,280
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by Druxus View Post
For me it isn't that I don't want the best performance. For most of my rigs space is limited and trying to find room for another lipo vs tucking a smaller castle 10amp bec is a lot easier. Or even with some of the newer esc with high amp outputs I can even eliminate the external bec. These setups give me more then satisfactory performance, so in the few models I have that I could put a extra pack in I don't because it works good enough for what I do with it.
This is pretty much the answer. The BEC is very small and can be stuck somewhere on the truck more easily than a 1000mAh 2s battery most times. Outside of what the servo sees power wise I also doubt many will notice the difference.
Sneetches is offline   Reply With Quote
Old 07-25-2019, 10:06 AM   #646
Newbie
 
Join Date: Aug 2016
Location: Orlando
Posts: 12
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

I am listening with great interest. The argument for where to put the second battery resonates. As some have noted, the servos work fine with BECs because crawlers 'are' different - I grok the fact they're not airplanes of helicopters. Only thing with a JST connector for external power, because the servo is limited to 2S, what happens when someone puts a 3S or 4S pack to it and it fries? Am I responsible? I think not but I know it'll happen. Also, none of this addresses the fact propulsion pack voltage is all over the map when the propulsion motor is engaged (yes, by even a little bit). So if you input variable voltage to the servo it gives you variable output torque. If you eyeball the specs for the DS470, for example, this can me between 360oz-in and 470oz-in and surely you don't want to receive less than you've paid for, do you? Anyway, I am 'not' saying I won't ever do this but instead, I am continuing to listen - with interest. Finally, if I can find some time I may well strap a WATT meter to a rig just to show you what I am speaking about because nobody else has done it yet. My point being, I still don't think much about the idea of giving a servo variable input voltage and short of showing you what it means in the real world it doesn't look like I'll persuade some of you.
jbeech is offline   Reply With Quote
Old 07-25-2019, 08:07 PM   #647
Tiny Truck Hoarder
 
HumboldtEF's Avatar
 
Join Date: Jun 2017
Location: Humboldt county
Posts: 2,254
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by jbeech View Post
Only thing with a JST connector for external power, because the servo is limited to 2S, what happens when someone puts a 3S or 4S pack to it and it fries? Am I responsible? I think not but I know it'll happen.

All electronics have their voltage limitations its no different than a motor or ESC, it something most people will consider but not all. I wouldn't bother worrying about it though, you post the specs on the package and thats all you can do. People who run in the 3S-4S range tend not to be novices so I think it wont happen too much.


You might also consider making a 3S compatible servo, I'd be very interest to try one.


Quote:
Originally Posted by jbeech View Post
Also, none of this addresses the fact propulsion pack voltage is all over the map when the propulsion motor is engaged (yes, by even a little bit). So if you input variable voltage to the servo it gives you variable output torque. If you eyeball the specs for the DS470, for example, this can me between 360oz-in and 470oz-in and surely you don't want to receive less than you've paid for, do you?

Yes Yes a thousand times yes, we are saying we do want less if it provides us with a simplified and more compact setup.



You say you're listening but you seem to not want to listen to this message: variable voltage is perfectly fine by us in fact most of us currently do this with our servos.


Your reasoning all makes perfect sense on paper but in a real world application some things are just different.

Last edited by HumboldtEF; 07-25-2019 at 08:09 PM.
HumboldtEF is offline   Reply With Quote
Old 07-26-2019, 06:54 AM   #648
Quarry Creeper
 
Join Date: Jun 2016
Location: Grand Rapids
Posts: 337
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

I use a battery for my servo, but since I have more of a shafty comp crawler setup [using relatively small batteries for both propulsion (3S 1000mah) and servo(2S 400mah)] my servo battery is actually smaller and lighter than the BEC necessary to power my servo. I can see how packaging would be more of a concern if you are running huge propulsion batteries for long trail runs as you would also need a relatively large servo battery to last the whole run. I do take my rig on trail runs at times, but I have to change the batteries in the middle at least once to finish the run.
Smokin' Joe is offline   Reply With Quote
Old 07-26-2019, 07:14 AM   #649
I wanna be Dave
 
WHITE-TRASH's Avatar
 
Join Date: Aug 2004
Location: Tri-cities, WA
Posts: 4,464
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by HumboldtEF View Post
All electronics have their voltage limitations its no different than a motor or ESC, it something most people will consider but not all. I wouldn't bother worrying about it though, you post the specs on the package and thats all you can do. People who run in the 3S-4S range tend not to be novices so I think it wont happen too much.


You might also consider making a 3S compatible servo, I'd be very interest to try one.





Yes Yes a thousand times yes, we are saying we do want less if it provides us with a simplified and more compact setup.



You say you're listening but you seem to not want to listen to this message: variable voltage is perfectly fine by us in fact most of us currently do this with our servos.


Your reasoning all makes perfect sense on paper but in a real world application some things are just different.

Exactly. "I'm paying attention but I don't give a shit what you want." Cool, other servo manufacturers do though so it is what it is.
WHITE-TRASH is online now   Reply With Quote
Old 08-30-2019, 02:53 PM   #650
Newbie
 
Join Date: Sep 2018
Posts: 41
Default ProModeler Servo: 420oz, billet case, o-ringed, $79

I finally got some time to conduct the test between a BEC and separate battery.

The rig is a 10.2 with a mamba micro and Hobbystar 4 pole 1900kv motor with a Promodeler 630 powered by a CCBEC. Rx tx is radiolink. Battery Is 3s 2300 90c

Some have stated that a small battery is still better than a BEC so I used the smallest battery I have.

For the test, I pulled the front driveshaft bolt so the front tires were static and raised the rear off the bench with a washer between the hex and the housing to introduce friction to simulate a typical motor load while crawling.

First test was CCBEC set to 8.4v, the meter read 8.39v so I set the throttle trim to a about medium size throttle and held the front tire while turning the wheel until the servo stalled and the voltage dropped to 7.5v

Next was a radio battery, venom 2s 350 45c. Meter read 8.2v and under load it dropped to 6.7v

Apparently a BEC is adequate.....




Sent from my iPhone using Tapatalk
Discohair is offline   Reply With Quote
Old 08-30-2019, 04:50 PM   #651
Tiny Truck Hoarder
 
HumboldtEF's Avatar
 
Join Date: Jun 2017
Location: Humboldt county
Posts: 2,254
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Thanks for going to the trouble of testing. Seems like the take away is that the size of the battery does matter and a small battery may have more voltage drop than a BEC run off a larger battery (I assume your BEC used a bigger capacity battery).

I wonder how things change with 3S, I would think with the extra voltage headroom that the voltage drop would still be above the voltage that the BEC is putting out. If that's actually the case it would seem like a BEC and 3S (or more) would be an even better result.

Any chance you have a 3S battery to test with?

Last edited by HumboldtEF; 08-30-2019 at 05:18 PM.
HumboldtEF is offline   Reply With Quote
Old 08-30-2019, 05:01 PM   #652
Newbie
 
Join Date: Sep 2018
Posts: 41
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by HumboldtEF View Post
Thanks for going to the trouble of testing.

I wonder how things change with 3S, I would think with the extra voltage headroom that the voltage drop would still be above the voltage that the BEC is putting out. If that's actually the case it would seem like a BEC and 3S (or more) would be an even better result.

Any chance you have a 3S battery to test with?


The CCBEC test has a 3s 2300 90c off brand battery upstream, but I canít use 3s direct to the servo because Iíll exceed the max rated voltage.

After that test, I tried a 2s 800 mAh battery with similar results and now Iím charging a 2s 5000 mAh battery to test.


Sent from my iPhone using Tapatalk
Discohair is offline   Reply With Quote
Old 08-30-2019, 05:16 PM   #653
RCC Addict
 
Join Date: Nov 2014
Location: Nowhere
Posts: 1,280
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by WHITE-TRASH View Post
Exactly. "I'm paying attention but I don't give a shit what you want." Cool, other servo manufacturers do though so it is what it is.
I think it's a bit unfair to Promodeler to say that. He's made repeated iterations of the 420 and now has the 630, of which he offers support for some mod with the Traxxas X-Maxx. None of that would have happened without listening to us. We all have our vices and JB's just so happens to be BECs .
Sneetches is offline   Reply With Quote
Old 08-30-2019, 05:23 PM   #654
Tiny Truck Hoarder
 
HumboldtEF's Avatar
 
Join Date: Jun 2017
Location: Humboldt county
Posts: 2,254
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by Discohair View Post
The CCBEC test has a 3s 2300 90c off brand battery upstream
Ah sorry I missed that part.
HumboldtEF is offline   Reply With Quote
Old 08-30-2019, 06:21 PM   #655
I wanna be Dave
 
Join Date: Jun 2016
Location: Deep in the Everglades
Posts: 4,660
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by Sneetches View Post
I think it's a bit unfair to Promodeler to say that. He's made repeated iterations of the 420 and now has the 630, of which he offers support for some mod with the Traxxas X-Maxx. None of that would have happened without listening to us. We all have our vices and JB's just so happens to be BECs .


Agreed. John has told us the best way to utilize his products. I love both my 420 and my 470.

Not to mention the simply best coolie!


Hang up and Drive
mikemcE is offline   Reply With Quote
Old 08-30-2019, 06:50 PM   #656
Newbie
 
Join Date: Sep 2018
Posts: 41
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by mikemcE View Post
Agreed. John has told us the best way to utilize his products. I love both my 420 and my 470.

Not to mention the simply best coolie!


Hang up and Drive


And based on my test outlined above, he is wrong...


Sent from my iPhone using Tapatalk
Discohair is offline   Reply With Quote
Old 08-30-2019, 07:30 PM   #657
Tiny Truck Hoarder
 
HumboldtEF's Avatar
 
Join Date: Jun 2017
Location: Humboldt county
Posts: 2,254
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

I agree they are great servos but I also think they could be improved just a little bit here and there to become simply the best servo hands down.
Take that however you want just know I want nothing more than to see good things come from PM and while a critique may on the surface look like an attack its meant to be helpful.
HumboldtEF is offline   Reply With Quote
Old 08-30-2019, 09:37 PM   #658
I wanna be Dave
 
Join Date: Jun 2016
Location: Deep in the Everglades
Posts: 4,660
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by Discohair View Post
And based on my test outlined above, he is wrong...


Sent from my iPhone using Tapatalk


I didnít see your noise information. IF you followed John is showing oranges, your looking at apples.


Hang up and Drive
mikemcE is offline   Reply With Quote
Old 08-31-2019, 08:07 AM   #659
Newbie
 
Join Date: Sep 2018
Posts: 41
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by mikemcE View Post
I didnít see your noise information. IF you followed John is showing oranges, your looking at apples.


Hang up and Drive


Please show where he stated ďnoiseĒ as an issue, his statements were always about variable voltages reducing torque while subsequent contributors claimed that a tiny battery that is smaller and lighter than a BEC would deliver more consistent voltage.

I called boloney and then performed a rudimentary test that showed the BEC to perform better than a small battery.

My next test will be with a 2s 5000mAh battery, which is bigger than my propulsion battery, but the claim that a small battery is better than a BEC for consistent voltage is dubious.

I welcome data to prove my data wrong, but moving the goal post doesnít help anyone.


Sent from my iPhone using Tapatalk
Discohair is offline   Reply With Quote
Old 08-31-2019, 08:08 AM   #660
Newbie
 
Join Date: Sep 2018
Posts: 41
Default Re: ProModeler Servo: 420oz, billet case, o-ringed, $79

Quote:
Originally Posted by jbeech View Post
OK, strap a WATT meter to your rig temporary like and go for a crawl. See what the voltage did. And airplane bubble or not, we still come back to the central question, why on Earth do you want a variable voltage supply for your controls? Don't you understand that means variable output from the servo - any servo. What's the fetish of using one pack instead of isolating the pack for control from the pack used for propulsion? A battery costs like $15-20 bucks and supplies the best juice money can buy. Or buy a BEC for more than that and it supplies garbage. I mean I grok why you use a BEC with a toy truck and a child because responsibility for managing two packs may be a bit much, but you guys are men and you definitely aren't running toy trucks. BECs exist for one reason, saving the manufacturer money. They have zero to do with performance. Zip. And variable voltage is nuts for every conceivable reason. It means your servo reacts differently as voltage changes. Why would you desire this? I really, really am perplexed why you'd want inferior performance after spending a lot for superior capability. It's like taking a world class sprinter and forcing him to run whilst carrying a 100lb sack of corn when competing with others not encumbered, e.g. handicapping him. Variable voltage handicaps the servo. Any servo, not just mine. But I remain with an open mind for a performance reason for doing this. What is the reason, having to do with performance, for wanting to operate your controls off a variable voltage source? I mean we bust a nut trying to extract the most possible performance from all the components and package them into our servo and some of you are basically telling me performance isn't important? Now I am really confused. Have you ever looked at the specs chart for our servos. We publish torque and speed for several voltages ranging from 4.8 through 8.4VDC and they mimic that of any other servo on the market. Less voltage means reduced torque output and increased transit time - weaker and slower . . . and this is a good thing?!? Note; this is true for every single servo on the planet. So when the propulsion pack voltage varies, the amount of torque you have available from your servo varies - and - the steering response is slower. Just for a moment imagine driving to work where your cars has less power steering sometimes and more power steering at other times. You'd take it to the dealer to have it repaired! Or perhaps driving it when the brakes are easy to operate sometimes and very hard to operate at other times. This would make for a very difficult car to operate. Same thing with these rigs when the voltage to the servos is varying based on the demand being placed on the battery pack by the propulsion motor. Reflect back on how throttle is applied to your rig. Is it a smooth application of power, or are you on and off the throttle constantly as you find a line and work your way up or down the course? Every time you vary throttle, not to 100% just varying it a little bit means the voltage is varying. Yet we design controls for the most steady source possible so that you get a consistent result. I keep seeking analogies. Imagine riding a bicycle with rubber handle bars so that as you apply torque to steer the bars bend and thus, you can't ever predict what the front wheels will do. That's in effect what some of you are saying you want, variable results.


Check my results


Sent from my iPhone using Tapatalk
Discohair is offline   Reply With Quote
Reply



ProModeler Servo: 420oz, billet case, o-ringed, $79 - Similar Threads
Thread Thread Starter Forum Replies Last Post
Billet Motorola Droid Razr Case JFAB Vendors Miscellaneous 2 01-14-2013 09:24 PM
Angry Apple Ipod billet case motoworx Vendors Miscellaneous 31 08-15-2012 07:12 PM
metal gears , billet case , coreless motor servo CHEAP BL-4x4 Electronics 2 01-04-2012 10:21 PM
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 06:44 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2014 RCCrawler.com