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XTM X-Terminator BL and Lipo 1/8 Buggy
Hope this is in the right place :W:
So anyways, this is my BL and Lipo buggy with some custom stuff. http://img.photobucket.com/albums/v1...r/IMG_0738.jpg http://img.photobucket.com/albums/v1...r/IMG_0739.jpg http://img.photobucket.com/albums/v1...r/IMG_0742.jpg It has: -Blue Bird BMS621mg servo -Custom modified upper deck (now only includes a mount for the servo) -Hitec 75mhz FM RX -Warrior 9918 (that I burnt out yesterday :mad: ) -Feigao 8L motor (bit too hot for this setup) -Custom slipper clutch design (read below) -Monster GT 52t -Custom aluminum center supports/motor mount for use with the center "transmission" -Industrial strength Velcro for mounting the battery(s) -Ofna rear "Super Shocks" with TiNitride shafts and teflon coated bodies -Custom made BEC unit The center slipper clutch was based off of the one for the Ofna Dominator. The reason why I made my own is that it costs a lot less, and I can better customize it. The slipper clutch itself is from the Revo, but the spur gear I am using is a Monster GT 52t one. The holes on it line up well with the holes already there on the slipper clutch unit. The spring is one that I bought from http://www.mcmaster.com where I often buy things in bulk (like bags of 100 screws or nuts). The collar is just a 6mm steel collar with a set screw. The center shaft is a modified one from the HPI R40. I tighten the slipper clutch by sticking one end into the vice, and use a hand clamp (the kind that you pump) to put the necessary pressure on the spring. Then I tighten the set screw down, and everything stays tight until I loosen the set screw. Here is a pic of it: http://img.photobucket.com/albums/v1...r/IMG_0749.jpg Now for some miscallaneous pics: This one shows how low the motor is (about 5mm): http://img.photobucket.com/albums/v1...r/IMG_0729.jpg This one shows the center unit (before I had the slipper clutch): http://img.photobucket.com/albums/v1...r/IMG_0726.jpg A close-up of the electronics side: http://img.photobucket.com/albums/v1...r/IMG_0731.jpg |
Thank you, looks good!
Too bad about your ESC! Can you guess a reason for its death? How many Volts have you ran thru it? Man, those tires are worn down. |
Well, I was jumping the buggy off of a jump I had made, and it landed, but then the 9918 just stopped working. I know it is the controller since one of my other motors wouldn't spin. But, the BEC works on it. I was only running 4s Lipo.
Yep, the tires are worn down. They work pretty well on the street though. |
Oh, crap! Take the shrink off and see if you can find an obvious damage. I've heard some SMD components can pop off.
Do you have the ESC directly on the chassis with those zip-ties, or do you have some foam underneath it. Already your second BK mishap, right? Sorry to hear. |
The reason why I haven't taken the shrink off is because I don't want to go through any problems when it gets sent back (extra charges). But if you are sure that they won't charge much extra, then I will do it. The controller was zip tied on, but I had industrial velcro underneath to keep it more secure on the chassis. Yep, 2nd Warrior 9918 to stop functioning... The first one took 4 months to get back to me.
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Actually, the BK people are really nice. I met them last weekend on a boat race, and they replaced my 9918 with the Brake Fade (altough, I sent it in once, and got it back unmodified, but got told if the problem persists, I can change it)
However, about taking the shrink off. You gotta have a look at it. I think re-shrinking is not that much of a deal for BK. And if you see something obvious, you might fix it yourself. So far, the BK support was always very quick for me, but I live in the neighboring country. You could always go thru Mike, they respect him alot. |
Then I will try it.
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Yeah, have a look. Won't hurt.
What Lipos are you using? (sorry if I missed that bit somewhere else) Do you like Lipo? Would you sugest it to me? |
I think I found 2 problems on the circuit, but only one of them is for sure. Here is an overall pic, with the 2 areas circled:
http://img.photobucket.com/albums/v1...e/IMG_0752.jpg This first part looks obviously broken. Dafni (or anyone), would you be able to take a pic of your 9918 so I can see if I could order that part? http://img.photobucket.com/albums/v1...e/IMG_0756.jpg The second thing I am not so sure about. It does look like there could possibly be a surface mount capacitor/resistor missing, but I can't tell for sure: http://img.photobucket.com/albums/v1...e/IMG_0757.jpg Dafni - I am (was, lol) using 2 custom made packs. The one in the pics is a 3s2p configuration of Maxamps 2250mah cells (11.1v, 4500mah). It works well. I customized it with taps to each 2p group, as well as a whole pack tap so I can plug in a LVC (low voltage cutoff) device. The other pack is made from 8 Dymond 2000mah cells in a 4s2p configuration. I got each Dymond cell for $12, which was a steal. This pack has taps for each 2p group. In case you don't know what taps are, they are just a way for me to monitor the voltage/charge each group of cells in parallel, so for a 4s pack (4 cells in series), there are 4 taps. Same goes for any pack with a certain number of cells in series (6 for a 6s pack). I would definately suggest Lipo, as long as you are willing to make sure that each cell doesn't go below 3volts, and that you take caution with them. |
Metalman, I would rather not open my warriors tonight. I'm sure Mike will get back on this.
This first part's definitely damaged. And the second could indeed be a missing resi. Wonder what Mike will say. Thanks for the info, I'll have to re-read the Lipo part. |
I think the second part is in fact a surface mount resistor. I think it is possible that the controller got hot enough that it melted the solder on it slightly, and then it got knocked off by the jump. If I had to take a guess, I would think that the part is this one:
http://www.mouser.com/index.cfm?hand...oductid=313900 The first one is so badly broken that I can't tell what it is. And I would definately rather replace it than send it to BK and wait mroe than a month (don't have that kind of time). |
With Mikes help and a bit of SMD soldering skill, you will be able to fix this yourself.
BTW, nice and quick foto-job! I like the circling. I don't have a camera of my own, unfortunately. But it would be handy. You made me think... |
The first part is the problem. Please e-mail me the picture(mike@rc-monster.com) and I will have BK send the part with my current order. I can then send it to you. I may have the part on another controller (I keep some controllers around for parts, incase these situations come up-I would rather fix myself and get the controllers back to my customers than pay the high shipping cost and wait the time to get it back from Germany). You could also send the controller to me and I will fix it for you.
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Dafni - I actually took ALL of the pictures with my video camera... They are pretty low quality. My dad just ordered the Canon Powershot G6 last night ;)
Mike - sent you an email with the picture. How soon will your next BK order be shipping? Also, my soldering skills aren't too bad. I've done circuit board work before, so I think I can handle it. |
the soldering is pretty easy, actually. I got your e-mail, etc. and will get the part on its way to you.
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Heh, cute buggy Travis, mine flies better though. :p
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But mine's lighter :). You also got yours tuned by some pros!
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Bah, who needs light weight? That just means I'd have a better chance at surviving a crash, because as a 70's luxury car ad once said: "Bigger is safer." Just change that to heavier, I guess. :L:
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In case anyone is curious what is going on, here we go.
Right now I am making a chassis out of 1/8" 6061-T6 aluminum. So far I just have some holes drilled. This chassis will be an electric-only chassis. I have been inspired by starscream to finally make it. One thing I am thinking of doing (after some research) would be to use a pushrod (Revo) suspension up front, like the Predator X-10. The custom mounts (if I do this) would go onto the custom chassis. As discussed in another thread, I want to make a slipper-diff. It would be a diff with a built-on slipper clutch (to save gears). I will probably be using a Savage diff because of low cost Ebay parts, but I might end up using a LST diff if the Savage one doesn't work out. |
Sounds really ambitious Travis. I'm looking forward to the end result!
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Quote:
Yours sounds very interesting. I wonder how your front end will look. Thought about the room the shocks would need? Keep it up! If you make a custom plate, why not machining some battery slots into it? Like a Gorilla chassis. |
Dafni, the front end will look weird! The reason I said I would do some research on this is because I have no idea which parts I will end up using. But I am thinking of using Revo shocks, and maybe Revo rockers, but we will have to see. I know the shock mounting will have to be custom. For now, I just want to get the lower plate finished so I can at least run standard front suspension. The only problem with that is that I don't have a controller to use! (both of mine are in for repair)
I could put in some battery slots, but since I use a scroll saw (unfortunately not a mill), I have cut each individual slot out, removing the blade and putting it back on after each slot. Besides, who needs battery slots when they run Lipo ;). |
I got an update on the chassis already :). I got the front and rear ends mounted, along with the steering bellcrank, and even got the front kick-up in. The chassis is only roughly cut once it gets away from the front/rear ends, because I wanted to allow maximum space for mounting things on the chassis.
http://img.photobucket.com/albums/v1...r/IMG_0863.jpg http://img.photobucket.com/albums/v1...r/IMG_0865.jpg http://img.photobucket.com/albums/v1...r/IMG_0866.jpg |
Did the stock XTM chassis have kick up? I gotta say it looks great, just put some junk on it already! :D
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The stock chassis did have the front kickup. I actually had to do that because the plate that goes from the differential case to the bellcrank has a bend in it. Besides, kickup is actually a good thing :).
I have marked out the holes to mount the servo plate, so I will do that next. Now I am thinking about the pushrod suspension. I may not be able to do it because it could interfere with body mounting. |
You mentioned the custom chassis is 6" wide, how big was the stocker? Also, just to clear something up, you only widened it, not lengthened it, right?
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The stock chassis is about 5 3/4" (5" of flat space) wide at the widest pint (at the back), but then it tapers to 4 1/4" (3 1/2" flat) at the bellcrank. What I mean by flat space is that 1/4" on each edge is taken up by the bent edges (to increase strength). Then, the mud guards make the outer edges of the chassis parallel with the center line (and the body). So basically, there is no secure space for battery mounting on the stock chassis, which is the main reason why I made a new one :).
This chassis gives the same exact wheelbase as stock. I kind of wish I had remember to make the wheelbase about 1/2" longer, but it is fine. |
Nice work!
Did you get your controller back yet? I would recommend mounting the controller on its side and off the chassis. I used a thin piece of angled aluminum and zipped tied my controller to it. This allowed the controller to sit off the chassis and not take a direct hit or impact. You can use other materials to cushon the controller but they don't help disipate the heat. Mounting it on its side seems to be more space efficient in those close quarters. I'd like to see it when you have it rtr Lookin Good |
I don't have any controllers right now :(. Mike has my 9918 (seeing if he can fix it), and my MGM 120amp (old version) is in the Czech Republic right now (although MGM won't tell me that it is).
The 9918 was mounted to the rock guard with velcro inbetween the rock guard and the controller. There were also zip ties securing the controller. The rock guards allowed some give (as plastic is flexible), but I guess it just bottomed out too hard. With the new chassis, I will probably be mounting the controller on the front left part of the chassis. That seems to be the only spot for it. |
Got an update :). I have the lower plate cut and put together (all holes drilled), and I have a new motor mount/tranny mount.
Chassis - This chassis now has 2 aluminum angle pieces. These serve 2 purposes: they strengthen the chassis (since I couldn't angle up the edges of the chassis) and they are for battery mounting. The clear (1/8") pieces you see next to the angle pieces act as raised platforms for the batteries to sit on. With this new mount, I can fit up to 7 NiMh cells per side! The widest battery I can mount on each side is 50mm (about 2"), which is wider than what is usually used. I plan on cutting holes from the chassis once it is finished to reduce the weight. These holes will be strategically place so that the chassis will be lighter but still maintain good strength. Motor mount/tranny mount - This design is new for me. When I first built a vertical mount, it was from 1/8" thick aluminum, and it bent very easily. This one is cut from 1/4" aluminum (like the last mount), and is very strong. Between the front bearing support (for the slipper clutch) and the motor plate, the spur gear spins freely, which took me about an hour extra to finally get to work. Both the front piece and the motor mount will have screws that will attach to the angle pieces on the chassis, which will give extra strength to keep the whole unit together. The top plate should keep the motor plate from wobbling and bending. If you look closely at the upper plate, you will see 2 rear-facing holes. These are there so that sometime down the road I can add a motor brace to keep the rear endbell from popping off. Here are the pics: http://img.photobucket.com/albums/v1...r/IMG_0898.jpg http://img.photobucket.com/albums/v1...r/IMG_0903.jpg http://img.photobucket.com/albums/v1...r/IMG_0895.jpg http://img.photobucket.com/albums/v1...r/IMG_0901.jpg |
That is nice. I hope mine turns out that good. Would it have been better to put the aluminum to the outside. Help protect batteries better and keep them on buggy to. Just a thought.
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I could have put the aluminum angle on the outside, but then the vertical part of the angle pieces would be off the chassis, which could reduce the advantage of having them on the chassis. To protect the batteries, I will be putting the mud guards back on, and I am thinking of getting some polycarbonate angle and using that to protect the edge of the batteries, and also to provide better battery mounting. I will see if I can find the correct angle pieces first.
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It's been almost 4 months since I have updated here! My buggy has gone through a modified chassis from the last picture, and just recently I made another new chassis to accomodate my LiFePO4 batteries.
http://img.photobucket.com/albums/v1...r/IMG_1684.jpg This is an overall picture of the buggy. You can see the servo mounts (in front of motor), but with no servo. http://img.photobucket.com/albums/v1...r/IMG_1698.jpg Here you can see all of the electronics (or would, if I had a servo). On top of the center slipper clutch support is a MGM Compro 12012 (yes, it did finally come back). I have it on 2 layers of foam and secured by rubber bands for a tight fit that will allow some movement in the event of a bad crash or hard landing. You can also see the motor, a Feigao 540C 9L. The mount for the motor is new, and mounts to the chassis using 3 screws, and is secured to the top plate using 2 screws. The front bearing support is screwed into the chassis with 2 screws, and also to the top plate with 2 screws. The rubber bands around it are for mounting an external BEC, and I will be getting this one: http://www.xushobby.com/servlet/Detail?no=38 Also visible is the receiver, which is mounted using velcro. To the left of the receiver is the antenna mount, and you can just barely see the white of the antenna tube. http://img.photobucket.com/albums/v1...r/IMG_1689.jpg These "front" shocks replaced the older ones that didn't look as good and were broken. I say "front" because they are actually the shocks for the rear of the buggy (from when I bought it), but they give just as much travel as the stock front shocks. The reason why the preload is like that is because I am also using the stock front springs, which are (obviously) shorter than the rear springs. I need to get some stiffer springs for the front, though. http://img.photobucket.com/albums/v1...r/IMG_1693.jpg A close-up of the battery mounting. Those velcro straps are custom made. The black piece that connects one of the straps was found on the ground, and since I didn't have another one, I made one from polycarbonate. You can also see the use of a foam pad, which is there to provide a small amount of shock absorbtion. You can also see how I attached the front and rear chassis braces (the turnbuckle things) to the aluminum angle piece that is used for battery mounting. http://img.photobucket.com/albums/v1...r/IMG_1702.jpg This is the (famous) LiFePO4 that I have been talking about for so long. It is comprised of 15 cells total (3.2v 1200mah), and there are 5 blocks of 3 cells in parallel (5 groups of 3.2v 3600mah) that are put into series (so 16v 3600mah total). This pack weighs about 150grams less than 12 NiMh cells, yet will perform like 14 NiMh cells or better. The construction of the pack has the nickel strips soldered together, and between each 3cell group there is a wire to give greater amp-handling capabilites (these wires are put on like they would be for a side by side NiMh pack). There are 2 sets of power leads coming from the pack because my charger (Duratrax ICE) can only charge up to 4s Li-Ion (this pack is being charged as Li-Ion), so I split it up into a 3s and a 2s. The whole pack is put into series by a series adpater. http://img.photobucket.com/albums/v1...r/IMG_1706.jpg And here is the battery mounted, snug as a bug in a rug :). The battery isn't going anywhere unless the battery straps decide to rip. They say a picture is worth 1,000 words, and in this case that is true! Sorry for the lower-than-expected quality of the pictures, I couldn't get the lighting right. The next things that I will do include: -Put some sort of mud guard on the left (motor) side of the chassis to prevent crap from getting into the motor and receiver. -Cut and drill holes in the chassis to remove weight. -Get a new servo and UBEC. -Get stiffer front springs. |
Damn, it has been over a year...
Let's just say the X-T looks nothing like that anymore besides the front and rear ends. I went back to the stock chassis and made a new motor/diff mount setup that puts the motor in the front-left corner. I had been driving this buggy with Maxamps 4s 6300mah (2100HV cells), but one parallel group puffed up. So I sent the pack back to Maxamps, and Austin verified a complete pack replacement. However, when I got it back, only the puffed up group had been replaced (I even included a detailed letter and references). So, I hacked up that battery pack for the loose cells, since I didn't want to deal with it any more. The buggy has just been sitting on a shelf for the past few months, waiting for a battery. I think I'll let it share the 5s2p A123 pack from the Revo) for some insane power. I have some pics from a while ago that show it in its current form: http://img.photobucket.com/albums/v1...IMG_4285-1.jpg http://img.photobucket.com/albums/v1...r/IMG_4287.jpg http://img.photobucket.com/albums/v1...r/IMG_4288.jpg http://img.photobucket.com/albums/v1...r/IMG_4290.jpg The battery mounts shown were for the 4s 6300mah pack, but I'll remove those when I work on the buggy again. |
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