Lunchy 27 Posted October 15, 2019 Hello - I just bought a Lunch Box to build. I have not done one of these in almost 30 years so I am very new to it. First thing that is confusing me is that I have a HiTEC HS-645MG servo. Do I use the servo arm that comes with the servo or the one that came with the kit? I see that the ones that come with the kit are Futaba, Tamiya, Sanwa and Acoms. Will these work with a HiTEC servo? Also should the servo saver still be used? thanks Share this post Link to post Share on other sites
lowspot 299 Posted October 16, 2019 Hi Lunchy You can use the servo saver that comes with the kit. There is for sure an adapter included to fit your servo. The standard servo saver is a weak point an can be updated to a better one later. Try "Tamiya 51000" at ebay and you will find the updated version. A lunchbox is a great kit to start with ! 2 Share this post Link to post Share on other sites
NobbySideways 113 Posted October 16, 2019 You just use the one that comes with the Tamiya kit, but it doesn't sound like the right one is supplied. I can't remember which fits which off the top of my head but if you gently try a couple of the options supplied with the lunch box you will find if the right one is present it slides on relatively easily wheras the others won't. I THINK Hi-tec is 24 tooth. Don't force it if it won't go, but the correct one will take a little pushing to get it seated, its hard to describe. Make sure you have test-connected it all first so you can fire up the radio gear and centre the servo before you fit the arm (make sure your transmitter trims are zeroed). Another tip, it can be quite easy to strip the threads on the screw in the middle of the servo drive shaft on a plastic shaft so don't grolly it up too much. If you worry it will shake loose a tiny dab of threadlock on the screw helps retain it, or failing that a miniscule amount of superglue (I mean really, really tiny). Personally I always use a servo saver, you lose a little bit of steering accuracy on the cheaper (and kit supplied) ones, but you also don't end up replacing damaged components as much. It's not just the servo that the servo saver saves. Share this post Link to post Share on other sites
NobbySideways 113 Posted October 16, 2019 Sorry lowspot, must have been posting at the same time. I can't seem to edit my posts from my work PC for some reason, so sorry for the extra! 1 Share this post Link to post Share on other sites
geniusanthony 361 Posted October 16, 2019 7 hours ago, Lunchy said: Hello - I just bought a Lunch Box to build. I have not done one of these in almost 30 years so I am very new to it. First thing that is confusing me is that I have a HiTEC HS-645MG servo. Do I use the servo arm that comes with the servo or the one that came with the kit? I see that the ones that come with the kit are Futaba, Tamiya, Sanwa and Acoms. Will these work with a HiTEC servo? Also should the servo saver still be used? thanks HS-645s are great servos non-standard 24 spline though. The kit supplied servo saver parts fit a 23 and 25 spline. If you have a shop nearby, it should be a simple matter to find an aftermarket servo saver with the appropriate dimensions. If you are in the US, I recommend Kimbrough #123 as they are generally very available. Share this post Link to post Share on other sites
Lunchy 27 Posted October 17, 2019 Just as a try I put on the Futaba/tamiya one and felt like it fit well. Not loose and not too tight. I'm not sure what is should feel like though. I talked to my hobbie shop friend and he said he thought that the kit would come with a 23,24 and 25... sounds like that is not the case. Share this post Link to post Share on other sites
Lunchy 27 Posted October 18, 2019 Would the Kimbrough 201 or 123 be the best bet? 201 kind of looks more like what came in the kit. Share this post Link to post Share on other sites
geniusanthony 361 Posted October 19, 2019 I can't answer that without knowing the geometry involved. TBH if everything clears and the distance between the servo center (screw) and the ball studs is similar it won't matter too much. 1 Share this post Link to post Share on other sites
Lunchy 27 Posted October 22, 2019 Another question for you guys. I just tried to plug the ESC into the reciever and it doesn't fit. The ESC plug has like a tab on the side of it. Is this something I cut off with a model knife or is there and adapter? I uploaded a couple of images thanks again Share this post Link to post Share on other sites
geniusanthony 361 Posted October 23, 2019 Yes, note the wire colors when you plug it in. Black is ground, red is power, white and yellow are signal. Share this post Link to post Share on other sites
Lunchy 27 Posted October 25, 2019 Got a kimbrough 131. Looks like a good fit but what came with the kit sticks out about an 1/8 of an inch more than the kimbrough. Anyone know if that sounds like an issue? I guess it probably depends on the kit. Share this post Link to post Share on other sites
Winniez 8 Posted October 25, 2019 Remember the ball bearings too, they cost next to nothing these days. Share this post Link to post Share on other sites
Lunchy 27 Posted October 25, 2019 Ball bearings for the servo saver or just in general? Share this post Link to post Share on other sites
Winniez 8 Posted October 25, 2019 I meant just in general Share this post Link to post Share on other sites
Lunchy 27 Posted November 4, 2019 Making my way through the kit and it has been lots of fun so far. I am stuck on one step though... It is where you position the pinion gear... not sure what it means buy using the paper header from the screw bag. Is this for the depth that the gear needs to go to on the motor? I have heard of using a piece of paper to mesh the pinion with the spur gear but not sure about this. I attached an image of the step in the kit instructions. Any help would be great! thanks! Share this post Link to post Share on other sites
Saito2 6573 Posted November 4, 2019 26 minutes ago, Lunchy said: It is where you position the pinion gear... not sure what it means buy using the paper header from the screw bag. Is this for the depth that the gear needs to go to on the motor? Yes, they are referring to how far (depth) the pinion gear goes down on the motor shaft before tightening up the grub screw. The bag header is used as a make-shift spacer for depth between the motor can (where the motor's end bushing resides) and the bottom of the pinion gear. Share this post Link to post Share on other sites
Lunchy 27 Posted November 4, 2019 Do you just poke a whole with the motor shaft through the paper and push tight against the motor with the pinion gear or keep it somewhat loose? Share this post Link to post Share on other sites
Saito2 6573 Posted November 4, 2019 I just slide in from the side, up against the side of the motor shaft (but not poking it through) and bring the pinion down until it meets it, keeping it somewhat loose and not crushing it tight. Share this post Link to post Share on other sites
guggles 79 Posted November 4, 2019 take one of the top paper tags off the screw bags you've opened and then slip it inbetween the gear and the motor. it doesnt need to be so tight that you cant pull the paper out afterwards just snug. Tighten the small screw on the pinion gear before you pull the paper out. Be careful not to over tighten the screw on the motor gear. Nice and snug will do it. I always use a very small amount of blue threadlocker on the grub screws for pinions because they have a habit of shaking loose. Share this post Link to post Share on other sites
Lunchy 27 Posted November 5, 2019 If you use the threadlocker are you able to get it off if needed? thanks! Share this post Link to post Share on other sites
guggles 79 Posted November 6, 2019 Blue threadlocker is low strength which will allow you to remove the screw if needed. Share this post Link to post Share on other sites
Lunchy 27 Posted November 10, 2019 Here is another one that has me baffled. I have this part that is not shown anywhere in the instructions. It looks like a gear. It is not even in the parts list. I have a pics attached. Any help would be awesome. You guys have been great!! Share this post Link to post Share on other sites
a.w.k. 664 Posted November 10, 2019 58 minutes ago, Lunchy said: Here is another one that has me baffled. I have this part that is not shown anywhere in the instructions. It looks like a gear. It is not even in the parts list. I have a pics attached. Any help would be awesome. You guys have been great!! Share this post Link to post Share on other sites