 |
- Cotharyus
[ 20 hours, 43 mins, 3 secs ago ] - JohnRobHolmes
[ 10 months, 3 weeks, 3 days, 11 hours, 59 mins, 5 secs ago ] - Kidrock
[ 11 months, 3 weeks, 1 day, 18 hours, 25 mins, 20 secs ago ] - test
[ 1 year, 3 weeks, 1 day, 2 hours, 57 mins, 0 secs ago ]
|
|
|
|
Welcome to Cotharyus.net - it's all about me. Really. |
|
|
|
|
Actually it's all about what I like to do. Call it a hobby blog. You could find anything here from R/C racing or rock crawling, to paint ball, to beer making. Expect the unexpected, notes on how to do things, and how not to do things. And if you want to talk about these things? Well, we might just set up some forums about them. Check in often for new news items, or just a funny story.
If you can't find what you're looking for here, you can ask me a specific question in the forums. For additional Rock Crawler information, you can also head over to rccrawler, one of the best crawling resources on the internet. They can also hook you up with great vendors like holmeshobbies that specialize in crawler parts.
|
|
| E-MGT or RC8MT. Either way, it lives. Are you paying attention Associated? | | | |
|
Although some of you have heard rumors, others have seen pictures here on the site, and participated in discussions here and other places, others may be completely clueless, because I never officially posted this project. I\'m know as a fan of electric R/C cars, it\'s what I started with, and there\'s something special about them. Unfortunately, electric is viewed as expensive - motor maintenance, batteries with short run times, chargers. You get the point. Nitro gained a lot of popularity, and with 1/8 scale monster trucks, it hit a sweet spot. They work for racing, bashing, fantastic feats of R/C flight - they\'re big, tough and impressive. Unfortunately, they\'re also loud, messy, and there\'s a lot to take into consideration when you transport one. Lets face it, electric is simpler, but until very recently, there was nothing to match the scale and go anywhere capability of a nitro monster truck.
Recently, we got the E-Savage, and the E-Revo. I won\'t get into these here, but suffice to say the E-Savage isn\'t brushless, and the E-Revo, is not, in my opinion, a monster truck, it is something different. It\'s cool, but it\'s different. Plus, I already have radios, servos - I really wanted something I could bend to my own needs, something big, four wheel drive, and fast. I\'ve been racing a Monster GT for some years. I like it, and would never get rid of it, or do away with it. So when I heard about the Mamba Monster Max ESC, something that would finally stand the current it would take to really sling around a big heavy monster truck, I started looking around. A local racer was retiring all of his nitro gear, and selling a Monster GT rolling chassis. I bought that, worked it over, and eagerly waited for the MMM to become available, while planning out how it would work, and go together. Finally, everything was on the market.
The ESC:
The Mamba Monster Max is one bad animal. Capable of handling 200 amps constant load with up to 6s LiPo, equipped with a fan and 10 gauge wires, there\'s nothing that compares to it. And since it\'s a Mamba, from Castle Creations, it is, of course, programmable via your computer. I would like to say it\'s everything I expected, but Castle slipped in one place. This ESC has a 4.8 volt (or something less than 6 volts) BEC which is non adjustable. It would have been better for something designed for large vehicles to have more voltage available to servos, in my opinion. That said, this ESC has dealt with three runs, of increasing punishment, and never gotten over 115 degrees F, even though one run the ambient temperature was at least 97 degrees F. I have to plug my vendor, Holmes Hobbies, owned by John Rob Holmes. He told me he\'d get these in, and he did. I ordered mine from him, and had it in my hands, like always, more quickly than I had expected. There are people out there dedicated to excellent service, and John is one of them, I make it a point to do business with these people every time I get a chance. Additionally, John will supply you with information above and beyond what you can find elsewhere - believe me when I tell you, he tests this stuff, and probably abuses it worse than many of his customers.
The Motor:
The Medusa V2 motor powering this rig is a 4 pole brushless design. Rated at 2000kv, with a constant current draw rating of 89 amps, it\'s not going to stress the ESC. In fact, I wondered if it would be motor enough to heave this heavy truck around. It is. It\'s gotten the truck to over 30 MPH in (fairly tall) grass, up hill in my yard, it pulls massive wheelies, and it\'s super responsive on the track, the motor ESC combo allows power to come on hard enough to break the tires loose in a turn and provides enough control to allow a smooth slide through turns, continuing to roll on the power coming on to the straight - it\'s just plain fast. These motors are also relatively inexpensive compared to a lot of motors in this class, but I have to admit, the motor is certainly the weak link in this rig at the moment. It reached 180 degrees F on the same run the ESC hit 115F. On the same runs, the batteries came under the temp gun and showed ....97F - the ambient temperature. Eventually, this motor is going to be upgraded, although based on the mounting I\'m currently using, I may have to rebuild my mount when I replace it.
The Batteries:
The key to brushless performance, as anyone who has used brushless gear will tell you, is good batteries. That means batteries that can supply the current that a system needs to start up, the more current, the more explosive the acceleration, the more impressive the wheelies...you get the point. So how much current is enough? If you\'re shooting for a big rig, get as much as you can. My MaxAmps 8000 Mah 11.1 cell LiPos are capable of deliving 160 amps of continuous power. Wired up to throw both of them in at 22.2 volts, they\'ll spin the 2000kv motor up to 44k rpms, and with that much current on tap, it gets there fast. Now another word about a vendor. These guys at MaxAmps are top notch. I use their batteries in just about everything I own. Their service is fantastic, support is responsive, and they will discuss requirements for a project like this with you. Add to that reasonable prices (heck, fantastic prices if you consider the quality of the product you\'re buying) and I have to say it again - projects like mine would go no where without some of the fantastic independent vendors in this market.
With all the major components together, I built the motor mount from a steel shelf plate. A single thickness bolts to the chassis where the nitro mount fit to allow for gearing adjustment. A double thick upright to mount the motor to which is first welded together, then welded to the base with an overlap joint (one peice welded to the top flat of the plate the bolts to the chassis, the other welded to the outside edge) gives the motor mount enough beef to stand up to the torque this rig is making. I have not yet seen any sign of the mount flexing.
One major consideration was brakes. The MGT tranny is tough as nails, but there\'s no way to set it up to use the motor braking. You can also drop a half a pound out of the tranny by using the Associated Forward Only Kit. So I dropped in the FOC, and kept the mechanical brakes that are stock. They\'re good enough to stand the truck on it\'s nose anyhow. Downside - no reverse - upside, I might be good enough to not need it.
End results? It works. It\'s a sight to behold. it\'s nowhere near finished, I still have to sort out the suspension for a 13.5 lb truck, but there\'s no lack of power to tap here, and the future is wide open. Keep an eye out for updates, as this is sure to be a work in progress for some time. I also plan to have one of my photographers take some action pictures at some point. In the meantime, there are pictures in the image gallery here. | |
| Something you should know | | | |
| For years now, likely since the first time I rode a bike down my father's drive way, I have loved riding bikes. Even though that first trip down the drive ended up in an ill fated turn that it would take me several tries to master, something about riding was enchanting. As I got older the bikes and the hills got bigger, and making the turn became more and more important. My first mountain bike was a beach cruiser with a 10 speed conversion kit on it. After that, everything got a little more high tech. One thing that stayed low tech was my body, and I can tell you, you can only break so much of your body up and get away with it. After a while, it starts to catch up to you. A few years ago, my joy in riding all but ceased when I hurt my lower back. From that point on, I experienced some level of discomfort after more than a few miles on my trusty mountain bike, which had by that time evolved from the beach cruiser, through several other bikes, into a GT Zascar Race. What to do? This discomfort dampened my enthusiasm for riding. I was at a cross roads, with biking and pain one way, and not biking and the misery of that the other way. As I was standing at this cross roads, I saw a funny bike go by, down a road I hadn't seen before.
The funny bike, was a recumbent bike. One that lets you ride in a more relaxed, supported position. I had to look long and hard to find out more, but in the end, I was able to locate one locally that I could ride. Then another I was able to sit on, but not ride, due to the adjustments necessary on these bikes to change the bike for the size of the rider. I knew I needed one of these. There was no way it could hurt my back to ride one. So I picked one up, and over 400 miles later, I can tell you, I was right, this doesn't hurt a bit. And I've still got a smile on my face. I get to keep riding, and do it without hurting. Interested? There are some pictures of my Scorpion fx in the gallery, and if you're looking for information there are forums at recumbentriders.org where you'll find nice people who can answer questions and get you pointed in the right direction. That's feet first, in case you were wondering. | |
| So, how about that helicoptor? | | | |
| Knowing the CX was an outmoded breed, I picked one up at a minor discount. The newer (CX 2) uses a different controller, and has some minor upgrades, all of which are compatible with the older CX. Already I am certain I can pick up the receiver for new model and use my DX7 to control it. It will happen eventually, but I'm waiting for the current unit to burn out, which happens, apparently.
Worthy of note is the battery situation here. The CX comes with an 800mah LiPo, of the two cell variety. A new one costs about $30 bucks, and it's handy to have two of them, since flight times are, lets face it, short, at about 6-10 minutes. Of course, until you can fly the heli, there's no getting that much flight time around repairs. But in case you pick it up fast, pick up a commonsenserc.com pack instead of the E-Flight one - it costs all of $11, and it's a quality pack.
Speaking of repairs, blades for the CX are easy. They come in four packs, for $4, and all you have to do is screw them on. Except that you really should balance them. I use two cans of green beans to balance them on, and put packing tape on the underside of the light blade to get things evened up. Trust me, it makes a lot of difference.
Out of the box, these helicopters aren't much good out doors, but flying them indoors may prove to be too much of a challenge, especially if you have pets, small children, or a wife that likes lots of knick knacks. That said, if you want to fly it out side there are two things you should do. First, drop the stock tail assembly, and build or buy a slim shaft style tail. You can use an arrow shaft to get a good start. The other thing you need to do, is shorten the fly bar, otherwise you'll get blade clash, or the bottom blade and the fly bar will strike, and this will bring your bird down. Trust me. Do both of these things, and these helis may be able to fly in winds as high as 5 mph.
Fun? You bet. What do I like so much about it? You have to think to fly it. Just like when you're bashing with cars, you can relax a little, but you have to think every second of a race if you want to win, you have to think every second this thing is in the air if you want to keep it in the air. It's a challenge. And it's fun. | |
| Witty Monk? You bet, and it's something to smile about. | | | |
| The Witty Monk has been un-capped, and it's everything is pretended to be. It's a crisp wheat beer, with a great citrus overtone. I've talked about this beer for a long time, I've wanted to make it, but I didn't know where to find it. Turns out, you can get it out of a kit. And it's great stuff. Honestly, this is going into my summer-stock list. There are a few beers I like to keep around and this is going to be one of them.
What's in the future for beers? I started two more batches this weekend, to be bottled in a few weeks. I'm turning my second batch of Sticky Wicket (it's an oatmeal stout - look through past news, and you can find it) and yet another batch of St. Patrick's Irish stout. If you like a good dark beer, this is the stuff. For my next trick, I'll be working on some witches brew - a light wheat beer with boysen berries in it. It will be my first venture into beer with actually adding fruit to the fermentation cycle. Should be intersting, and perhaps another great summer brew. | |
| I recently added a Blade CX electric helicopter to my R/C collection. At under $200 for a completely ready to fly set up, I figured it was worth it. The catalyst was a friend coming over to the house shortly after Christmas. He brought his son with him, and his son brought his new airhogs heli with him. I messed with it for a few seconds and though to myself, self, you need one of these. Being me, I poked around a little and discovered that like usual, you could get the cheap toy, or you could get something a little nicer that you can get parts for when you crash it horribly. Speaking of parts, main rotors are about a dollar a blade, which is good, because I cleaned two blades off on my first flight - within two minutes in fact. But after fixing those two, I flew the rest of the pack without incident. Really, this is all about the challenge. I've wanted to get (back) into flight for some time, particularly since I have some property to fly on. Onwards and upwards. I'll be posting as I figure out some tricks I sure. But first, I just need to get the hang of it. | |
| New beer for the new year | | | |
| To start the new year off, it's always handy to have beer on hand. So I do. Recent batches have been great - the whispering wheat was crisp and smooth - you couldn't find a more text book beer, and everyone that had it was delighted with it. I also brewed up a batch of Irish Stout, which was a deeply smooth and enjoyable as ever. For the new year, I've started a batch of one of my standing favorites, the Heavy Bock, and something new. It's a new receipt they have called Witty Monk.
Witty Monk is a wheat beer (have I mentioned I like wheat beers?) that is spiced, rather significantly I'd say, judging from the smell, with orange. The smell of the steaming wort made me impatient about the fact that this beer is going to take a month to be ready, if I rush things. In the meantime, I'll be putting in another batch of Irish Stout, and somewhere along the line brewing up another batch of Sticky Wicket, and trying out some Witches Brew. | |
| I haven't talked much about LiPo batteries. But I should. They are the new thing in R/C, which in combination with brushless motors are rapidly bringing the electric class back to the track, and increasing numbers of bashers are using them for the additional power and run time as well. But if you've heard about Lithium Polymer batteries, you've likely heard that they are dangerous as well.
Dangerous batteries are nothing new to long time RC fans. All battery technologies were originally introduced as "dangerous" to the R/C world. There are constantly warnings that you shouldn't over discharge cells, over charge them, discharge them at too high a rate, or charge them at too high a rate, as all of these things can made just about any cell we've ever used to power our beloved toys explode. The same goes for punctures. All of these same things are being repeated with the introduction of LiPo technology.
There is good news and bad news to go with all of this. The bad news is, they've always been right. All of these things could cause cells to explode or otherwise permanently damage the cells, which historically have been relatively expensive. The good news is, every time there is an advance or change in technology, new tools come along to make it easier to safeguard the batteries, and the introduction of LiPo technology has been no exception. The chargers designed for these cells are very advanced, and easy to use, some having as few as 3 buttons no them. Using one of these chargers, on a healthy cell, it is very nearly impossible to cause problems during the charge cycle. Of course, you can still blow them up by discharging at too high an amperage. The good news is that some LiPo cells are capable of sustaining discharge rates that used to be unheard of, and would quickly result in the charboiling of NiMH cells, without becoming anymore than noticeably warm to the touch. Additionally, many new ESC's are coming with automatic voltage cutoffs to protect LiPo cells from being discharged too much. Discharging a LiPo cell to below 3.0V (a single fully charged LiPo cell is rated at 4.2V) will result in permanent damage to the cell, and it cannot be recharged. Punctures are another thing altogether. Crash damage resulting in punctures or dead shorts can cause LiPo cells to balloon and explode with a violence that previous cells were totally incapable of.
All that said, and being true, it is also true that with responsible handling, these cells are perfectly capable of surviving all but the most extreme punishment that most RC enthusiasts will dish out. Handled with care, these batteries can take RC to new levels of performance for several reasons. First, the current they can deliver will have your low wind modified or brushless motors launching with unheard of power. In addition to that, they are noticeably lighter than Ni cells. To top that off, capacities as high as 6000Mah will easily fit in many 1/10 scale cars without any modification to the battery trays. To put that into perspective, an Associated B4 with a Mamba 6900kv brushless motor will run for 30+ minutes on a 6000Mah cell. Now how many laps down is your nitro powered vehicle? As mentioned previously, a single LiPo cell at full charge is rated at 4.2 volts, meaning a peaked 2cell LiPo is rated at 8.4 volts, however 2 cell LiPo batteries are marketed as 7.4 volt packs. Three cell packs are marketed as 11.2 volts, these are widely used in rock crawlers.
Some confusion does exist over all of the "coded numbers" surrounding LiPo packs. For instance, a 2S1P pack would have two cells wired in series and be 7.4 volts, if the cells are 3000Mah, the pack would also be 3000Mah. A 2S2P pack will have four cells, two in series and two in parallel. If we assume the cells are the same capacity as the pack in the first example (for instance, 3000Mah) then this second pack would be a 7.4 volt pack rated at 6000Mah.
For my personal experience, I am running MaxAmps LiPo packs in my B4, and in my RC18MT. Both vehicles have brushless motors and are absolutely ballistic with the lighter weight and more available amperage. Although top speed is not affected much when comparing a peaked NiMH pack to a peaked LiPo pack, the LiPo pack will sustain its incredible punch throughout the discharge, while no other cell maintains the initial punch. This means that over the course of the discharge cycle, instead of seeing top speed and acceleration fall of, it stays consistent.
Charger wise, I like the CommonsenseRC LiPo charger. It balances the pack every time it charges it, which keeps the cells more closely matched, preventing a situation where you discharge one cell to below 3 volts because the other cell was more charged, thus ruining a pack.
Overall, I can find no reason to warn a responsible RC enthusiast way from LiPo packs for whatever application you need. I have plans to power my (yet to arrive) B44 with LiPo, and I also have a planned project to convert an MGT to electric power using LiPo cells, likely to be a monsterous 4S 16000Mah pack. Expect to see more on both of those vehicles coming soon. | |
| So, I've got the first few bottles of my first Wheat beer in the fridge, it's been there for a few days, and I figured I'd give one a whirl. Good stuff. It's very smooth, and quite potent. It's very pale, aroma is brilliant, and honestly, I couldn't hope for more. You gotta try this stuff. | |
| The current beer status stands thusly:
I am finishing off a batch of Heavy Bock. I get a lot of help from my wife on the Heavy Bock, it's one of her favorites. It's dark, malty, and has a good aroma, some consider it a pretty good approximation of the Guinness that's available in the US.
Moved to the fridge to finish conditioning, I have one Belgian Wheat beer - very light in color, and yet to be test, but I suspect this will be a crisp, easy drinking fall beer.
Still conditioning on a shelf in the brew room, I have one batch of Liberty Ale. It's an unknown quantity, likely to be very aromatic, and possibly have enough bite to limit it's consumers around here to me.
Also started this morning, are a batch of Pilot House Pilsner, which promises an interesting fruit twist, and St. Patrick's Irish Stout, which is a beer so dark, you have to light a candle when you open one, and so smooth people fight over them.
More to come when I've sampled the Wheat beer. | |
| For several months now, I've had a new crawler on back order. It got here a week or two ago, and I've been busy working on it. It looks like it's going to do pretty well, but we'll find out for sure on the 22nd when I head to Green River for Crawlfest 3. A few words. This is a top notch kit, especially for a newcomer. You can go any number of routes with it for electronics. But the kit, for the price, is not going to be beatable. It's even a good platform for an experienced crawler - any place that makes a good starting point, will make a good finishing point.
That said, for electronics I opted to use the Quark 33 brushless controler and a Scorpion 3014 out runner, both of which can be had from Holmes Hobbies, quickly and reliably. The reason I went with the Quark is because I had heard good things about it's low speed control, and accuracy. So far, I cannot do anything but heap praise on this little ESC. Even pushing the (more that adequately sized) 3014 outrunner, which provides fantastic low speed torque, and perfect wheel speed for this rig, the heat stays low on it, meaning I'm likely well within the 33 amp output limit of this control, even with the 11.1v LiPo I've got pushing it.
Bottom line, whether you're new, or experienced, if you're looking for a new crawler, you owe this rig a look. As many guys on rccralwer.com are happy with the kit's performance with inexpensive electronics as there are guys happy with higher end equipment in this rig. Good stuff. You can check out pictures in the gallery.
 | |
|
|
Guests: 1, Members: 0 ...
most ever online: 28
(Members: 0, Guests: 28) on 17 Jun : 07:42
Members: 4
Newest member: JohnRobHolmes |
|
|
[ Cotharyus.net - The Hobby Blog ]
