tag:blogger.com,1999:blog-7793811623191911228.post466590219786930026..comments2024-03-26T22:12:26.417-07:00Comments on The Dart Zone: RANT: The Battery Wars Rage Ontorukmakto4http://www.blogger.com/profile/10734470012890561585noreply@blogger.comBlogger11125tag:blogger.com,1999:blog-7793811623191911228.post-24934553519678301362015-12-07T07:58:20.758-08:002015-12-07T07:58:20.758-08:00Great post. I didn't realize there was so much...Great post. I didn't realize there was so much opposition to scientific fact. I knew there was a lot of ignorance, but I can't blame a 10 year old for thinking a 9v prism battery works just as well as an 8 cell eneloop battery pack with SCR pure copper battery bars, silver solder and a Deans connector.<br /><br />Keep it up; I appreciate your hard work! I'm constantly referring to your posts and blog posts for much solid and reliable information and data.<br /><br />P.S. Go Gators!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-58000633822070044202014-10-06T11:18:33.476-07:002014-10-06T11:18:33.476-07:00This is ridiculous. I was an RC racer before I st...This is ridiculous. I was an RC racer before I started Nerfing. I took one look at the Trustfire C rating and knew they wouldn't work. This was common sense to me. I installed a 7.4 Lipo into my Rapidstrike with a Dean's connector (this is the only connector I use). I took it to my first war. Everyone was impressed with the performance of the gun. Another Nerfer there showed me his flywheel gun with Trustfires. His flywheels took forever to spin up and I could hear the voltage sag when he would fire a dart. It was obvious to me. I can't believe people are giving you a hard time about advocating the use of Lipo over the Trustfires. I would tell people to try the Lipo and compare before flaming it. Brianhttp://www.bbex.comnoreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-82320552721320042732014-05-15T14:38:46.975-07:002014-05-15T14:38:46.975-07:00Good call, I should have given the comparison &quo...Good call, I should have given the comparison "proper mod".<br /><br />For reference, the cells I am running are about 13mOhm IR (the high-current power tool 18650s). They aren't the punchiest things out there but they still perform well and very robust.<br /><br />And yeah, the sig figs were all over the place in that. I will try to avoid it in the future.<br /><br />I will add you as a contributor and you can write posts. On that subject, if anyone else wants to be a contributor, say something.torukmakto4https://www.blogger.com/profile/10734470012890561585noreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-84164874921753789362014-05-15T13:32:31.635-07:002014-05-15T13:32:31.635-07:00I suspect that a good portion of the persistence o...I suspect that a good portion of the persistence of shoddy modding habits comes from people thinking that, if it's good enough for Coop, it's good enough. I don't blame him, though - he is running a business, so it is natural that he'd cater to people's expectations. <br /><br />I've done some calculations for the purpose of comparison with a properly-built mod. After all, the argument here isn't just that conventional practices leave something to be desired, but also that there is a much better way. <br /><br />The IR of hobby-grade Lipo packs varies widely. To avoid accusations of bias, I've used the worst of the numbers found here ( http://www.rcgroups.com/forums/showthread.php?t=1578001 ) which is 45 milliOhms per cell, for a total of 0.135 Ohms. <br /><br />The resistance of a decent connector is typically negligible, but I've rounded it up to one milliOhm and included it anyway. <br /><br />If 18 AWG wire is used, with the same length, the resistance will be 1/4 as much as with 24 AWG wire: 13 milliOhms. <br /><br />Including the motor, the total resistance is now 690 milliOhms - and most of that is due to the motor! The stall current is 16 Amps, which is almost double the calculated stall current for the shoddily-made mod and reasonably close to the ideal of 20.5 Amps. <br /><br />Come to think of it, if you added a section on why compensating for a high resistance with a high nominal voltage is a bad idea, this would serve as a handy refutation of pretty much the entirety of the TrustFires-in-trays modding style. <br /><br />Hmm . . . I'm tempted to write this myself. What's your policy on guest posts? <br /><br />(While on the subject of ways to improve the article: significant figures, man! This is one of my pet peeves - first year physics students get this one wrong with annoying frequency. On the other hand, I sometimes forget to round when I'm annoyed, too, and other people might not be bothered by this.)Herbert Westnoreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-26396097572065250132014-05-14T13:22:50.677-07:002014-05-14T13:22:50.677-07:00I was lucky, I joined this community relatively re...I was lucky, I joined this community relatively recently with no pre conceived notion of mods or "fashion" in Nerf, so maybe looked more objectively than those who have been nerfing longer. I think the quality of work from some people in this sphere over the last 9 months particularly, has been excellent and would hold it's own against other similar hobbies in terms of best practice.Anonymoushttps://www.blogger.com/profile/13950865980007553718noreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-84175932466642150792014-05-13T11:22:34.352-07:002014-05-13T11:22:34.352-07:00As long as people own TFs and chargers and lack th...As long as people own TFs and chargers and lack the capacity to understand the shortfall in the technology, this argument will continue.<br /><br />I fully understand why TFs were used in the first place and I think we have all used them at some point. The problem is whilst some people try to learn more about what they are doing in order to increase performance, there will always be the minority that just 'copy and paste' their practices between projects and, for one reason or another, refuse to take the next step.<br /><br />I'm fully behind you on this Toruk. I understand how it can be lonely up on that soapbox but I'm sure that people will come around eventually.UK Nerf Warhttps://www.blogger.com/profile/10443256952752367689noreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-4449981007482788942014-05-13T09:17:04.749-07:002014-05-13T09:17:04.749-07:00Great article, with a sensible level of technical ...Great article, with a sensible level of technical stuff. Even I understood that bit and my formal physics education stopped over 20 years ago. I still don't get why this is a problem for people, it's a non argument from start to finish. You don't see people advocating horses as better than cars for performance on highways, so why this slavish adherence to crappy and downright dangerous practices. I have been meaning to do a test of power supplies over the chrono, but it has taken a back seat to wars and Rapidstrike insanity the last two months. Wire, connectors and soldering equipment is stupidly cheap, about the same as a ton of crappy cell holders and useless batteries, plus you can use them for numerous blasters. Packs can be had for peanuts and chargers are sub $20, not far from crap TR ones. A good 2s or 3s can also be used in many blasters. With IMR still an option for drop in weirdos the TF debate just needs to go away!Anonymoushttps://www.blogger.com/profile/13950865980007553718noreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-37980927354360719612014-05-12T18:59:11.530-07:002014-05-12T18:59:11.530-07:00I totally agree, I could have left all opinion and...I totally agree, I could have left all opinion and anger out of this, and this post would have been a far better article. I may in fact copy the example/calculation portion and include it in a future page (like the chrono tab) about power systems.<br /><br />TBH though, this WAS in fact somewhere between blowing off steam about, and a response to, some extremely juvenile and ad-hominem things directed at me over this subject. I shall not name the posters or their venue at this time.<br /><br />Yes, some people leave thermistors in; i.e. green Rayvens. Motor inductors, and sometimes diodes, extra switches, and lots of surplus wire, too.<br /><br />You are correct that a generous approach was used. I figured it wise, to avoid any accusation of bias, and to justify my usual statement of "that is grossly inadequate" with not only an example, but a near best case example that is still quite disappointing.<br /><br />As to why the Stampede tray was pictured, that is because I had it, TBH.<br /><br />As to the tangent, I agree with all of it. The reason I think it is defended, and people continue to buy them no matter what cost/benefit situation, or analysis in terms of cost per watt-hour or lifetime cost, or performance or reliability, is twofold.<br /><br />One, it's status quo. There is an implicit sense that it's good and shall not be questioned or evaluated, even though it's actually not, and working within its limits is holding us back.<br /><br />But reason two is that it's not so much point missed or point disputed, but, damn not given. And I won't mess with that can of worms ATM.torukmakto4https://www.blogger.com/profile/10734470012890561585noreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-77339728783419501302014-05-12T16:05:01.386-07:002014-05-12T16:05:01.386-07:00Overall, this is a good article. The core technica...Overall, this is a good article. The core technical argument is well-put, though the (completely understandable) anger at the beginning is a little off-putting. If anything, you might have been a little generous with your assessment of noobish modding habits.<br /><br />It's shocking that people leave stock thermistors in to the point that you couldn't assume that they were gone (and had to mention that you were ignoring them).<br /><br />The Stampede tray shown in the pictures has another two spring contacts connecting it to the rest of the blaster, and the wire is attached to the tip of the spring inside the tray. If we assume that these springs are a 2x scaled-up version of the RadioShack springs, they have 4x the cross-section and 2x the length, giving them 0.5x the resistance - making for roughly another 20 milliOhms. Little things like this can add up to terrible performance. <br /><br />The points of contact between a spring/cell/flat tray terminal (which you chose to ignore) have resistance that is hard to quantify, but I wouldn't be surprised if it is large, especially if greasy fingers are involved, and considering the not insignificant number of such contacts in the tray system pictured. <br /><br />It's a little odd that you chose to picture this tray given that the analysis performed (looking at 4 springs in the tray, assuming flywheels) was more appropriate for a Rayven - but this is a very minor quibble. <br /><br />On a bit of a tangent, I'm seriously wondering whether ***fires are good for a primary power source in any Nerf blaster. On one hand, they have clear drop-in convenience for people who don't want to mod. On the other hand, anyone who can't trust themselves with a screwdriver and soldering iron really shouldn't handle batteries with an unstable chemistry prone to incendiary failures from a cheapo/ripoff manufacturer. Bad things could happen. So, ***fires would be good for people who want better (but not much better) performance, who are willing to pay almost as much as for a good pack, and who can be vigilant about their batteries, but for some reason won't mod (simple laziness perhaps?) That's a very narrow niche. <br /><br />In any case, this was well-argued and I hope that people learn from it. <br />Herbert Westnoreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-44547006177873116202014-05-12T04:28:14.737-07:002014-05-12T04:28:14.737-07:00Go get em Toruk. Tons of help from you on battery ...Go get em Toruk. Tons of help from you on battery issues during my experiments. I don't understand how anyone can be so close minded to not try a battery pack at least once to see that it is better.<br />And thanks for a shout out to Tamiya motors.Zombonanoreply@blogger.comtag:blogger.com,1999:blog-7793811623191911228.post-80917077399109843322014-05-10T21:32:48.155-07:002014-05-10T21:32:48.155-07:00I'm not sure if you're just really smart, ...I'm not sure if you're just really smart, or I don't know anything about the things i've done following your guides, or maybe a bit of both.. but you sure as hell know a lot about this stuff, and i'm glad you've helped me so much along with made well detailed guides to help others out. Just baby people enough and eventually they will understand and the word will get out. Keep up the good work.Anonymousnoreply@blogger.com