This is the ProModeler control arm/servo package for replacing the stock arm/servo in your X-MAXX but for this servo, the stock Traxxas #7749 servo adapter won't work so installing an 1155oz-in brushless high voltage all-alloy steel gear train high performance servo in this truck requires something different. Sorry but we're not in the loop about what racers use, instead.
So you can make it fit but making it function is tricky with respect to getting the shaft properly aligned without a bit of modding on your part. If this isn't your cup of tea, order the DS930 package instead because once we mod the servo for your order (the X-MAXX beam mod is part of this package), then once we ship, we won't issue a refund just because you're dumb and missed this detail thereby ordering the wrong item. Don't put us in the position of being the bad guy in this by whinging about not knowing, OK? Please consider yourself warned.
Note the offset of the splined shaft, do you understand what we're talking about? If not, give us a call but honestly, if you're calling, it's our opinion you're not up to doing this modification without hand-holding. Yes, this is our opinion having never met you but you should just trust us having your best interests at heart and order the DS930BLHV package, instead. No offense.
- The image shows the offset of the DS1155BLHV splined shaft vs. conventional location
The arm is part of a servo-package. Both it and the servo are CNC-machined from a solid billet of 6061-T6 aircraft aluminum. The arm is anodized red (there are loads of YouTube videos showing the oven cleaner method of removing the color of anodized aluminum). The servo is our most powerful standard size brushless all-allot case 1155oz-in servo modified to fit an X-MAXX - ProModeler brushless DS1155BLHV servo - click the link for details (this opens in a new tab). However, to save time; these are the highlights . . . 1155oz-in, billet aluminum case, brushless motor, steel gears, steel hard points, 13 o-rings, plus it meets:
- Shock - Test Method 516.6
- Vibration - Test Method 514.6
- Rain - Test Method 514.5
If you find a better servo, buy it. Tell us so we can improve ours.
- This photo of the Savox SB-2290SG gear stack vs. DS1155BLHV usual ends all questions
Pro Tip: in common with any servo in this class (+1155oz-in), the DS1155BLHV needs as much as 9A of current (not while loafing, but when it's working hard). At 7.4V this works out to a bit more than 65W (the case isn't finned for decoration, it gets hot) and at 8.4V this goes over 75W. The point is, either use a BEC with enough cojones to do the job, or opt for a separate 2S LiPo (like a nitro rig) because even an ordinary 30C 2S1000mAH LiPo will output 30A).
This begs the question; which is better, a BEC or a 2S LiPo? Honestly, it comes down to a bit of grade school math, and whether you value convenience over performance. We prefer batteries because their output isn't garbage and noise - but - everybody makes their own decisions. Honestly, we don't care because the servo will run on either source. Further info to help you decide which is best for you.
As for a BEC, we offer a 20A unit from Castle Creations CC BEC Pro 20.
Final note; your DS1155BLHV servo is supplied with the 'beam mod' where part of the beam closest to the output shaft is removed. This is so it fits within the Traxxas adapter.
- Any servo receiving a beam mod gets trimmed in the mill as in this ds630BLHV example
Last thing; if you'd rather not have a servo with the beam mod, just mention it in the notes when you order - but also note; this service is built into the package pricing (meaning they're on the shelf and while we don't mind swapping out the servo for one that's unmodified before shipping, we're not also going to take time to go into the computer and adjust the price of the order). Don't like it? We're sorry, it's the way it is.
- DS1155BLHV output bearing vs. Savox SB-2290SG . . . ours is substantially bigger
Pro Tip: Control horns will strip out when they come loose of the splined output shaft. Not much we can do about that because
it's on you to ensure the nuts and bolts on your model stay tight. Thus, you'll be wise to either use a chemical means to help secure it (thread locker - blue, not
red), or a mechanical aid, like with a star washer, or lock washer, etc. This, in addition to performing routine preventive maintenance on your rig, like checking the security of the important fasteners. Also it's worth trying to
see how long a bolt will actually thread into your servo (they're all a little different) and if you can use one that's a little longer than
the one we supply, then use a longer one to get more thread engagement.