Hey guys, a couple days ago I was talking to @RokSolid about doing a cnc LH KV gearbox build, and please don’t judge, I’m going to sound really, really stupid, this is my first time trying to properly shim aeg gears, I have no joke for the past 4 days come home from work and from 5:30 to 9 I’ve attempted to shim but just can’t get it right.
I ended up getting the the mk cnc gearbox (which I am very impressed with), a high speed motor from x force and a metal gear set aswell + a shimming kit (and other essential aeg upgrades)
Now I’ve watched countless tutorials on how to shim gears, start with the motor, pinion gear then bevel gear hight/meshing ect…
But no matter what I do, it sounds very terrible with just the motor and bevel gear in there, I’ve tried serval combination with 0.1 shims, I just can’t get it right at all and would love some advice from some people
What motor did you get?
The mk box is a little particular with the motor, more so on the length of shaft. It was modelled off a lonex motor which the shaft is “standard” length for a 480 short shaft… Now the gell ball things…
Many 480 short motors (chi hais particularly) are a couple mm longer, which on most gearboxes can be adjusted out to suit. Not possible on the vector box.
By the looks of it… And it is hard to tell the pinion is sitting a little deep on the bevel gear. Definitely would make it sound awful if that is the case.
The original chihai I had in the mk box had to grind the shaft down a couple mm… and then grind the flat spot down a couple mm to allow the pinion gear to be mounted a little shorter.
A painfully process of remove the pinion gear . Tape the motor up… coat it in tape so fillings don’t go into it. Then grind the flat section deeper so the pinion gear can go down the shaft further. Be sure to only grind what you need to away, and do your best to not touch the factory flat section and match it… a level of precision is required.
Then I set the pinion to the bevel gear and Loctite it on… then off to the grinder to remove the excess shaft protruding from the pinion gear. As mine was dangerously close to the bevel gears anti reverse points.
Painfull but worth getting it right!
Either grind or see if you can exchanged the motor for something that is shorter as is.
When I received the motor that was the first thing I did, like you said, grind out that flat bit for the pinion gear to sit deeper into the motor then cut the shaft so it is away from the bevel gear
Also when you say the pinion is too deep in the bevel, should I move the pinion back towards the motor or the bevel gear downwards?
Could I also be using the wrongs gears or somthing?
Too deep is usually needing to move pinion back towards the motor side.
If the edge of the motor gear is too close to the edge of the bevel gear, they can bind together and make a terrible noise.
Motors tend to have a lot of end float on the shafts, which might make the mesh look good sitting still, but then the magnetic force when the motor starts can punch the shaft forward when running, or the taper on the bevel/motor gears can push the shaft backwards under load.
Metal gears in a metal box without any lubrication or load applied to them via the mainspring, along with a metal AR Latch, can sound like a horrible metal banshee until fully assembled, greased and running under load.
Try to keep the smallest amount of shims on the underside of the gearbox, being wary of the vertical clearance between the AR latch and each other gear, to keep the sector gear as low as possible in the gearbox.
If you end up with the sector gear too high, this will ruin the alignment between the sector and piston racks, and also possibly cause issues with the semi fire interruptor lever if one is fitted.
Thanks heaps man, I’ll try this after work, I’ll move the pinion back and maybe try it fully assembled and under load, I haven’t tried it with the spring in or anything like that yet but I’ll give that a crack
Cool
Still get the shimming as close as possible before full assembly/greasing and testing, then can make any minor tweaks from there… but will sound a lot different to a rattly dry box of metal bits churning around!
Hard to see from the photo, but I reckon the pinion is a little too deep… and as for bevel gear mesh with pinion, it should be just close enough so you can “rock” the bevel gear back and forwards a little.
Tedious process, but good bevel and pinion gear meshing removes most of the noise of the gears. spur and sector gear are fine long as they don’t rub on each other… and have at least say 70% of the teeth contact. More is better, but I would rather have a 0.3mm gap between them than have them potentially rub each other.
Most wear will always occur on the bevel and pinion as they spin the fastest and are intersecting at 90°.
I wish SHS sold gear sets as spur and sector for your ratio choice, and bevel and pinion as they are the same across the board. (except helical gears)
Update…
I’ve moved and adjust the pinion gear and the bevel gear to the best of by abilities, I them shimmed the remaining gears, then assembled the entire gear box and see how it sounded.
I mean I don’t think it was bad but I can’t really tell if it’s the motor or the gears making the noise now, but it seems to cycle well
I’m just severely impressed that you working on a Vector gearbox!
The most difficult design to ever be invented in the whole history of Gelblasters!
Sure that the basic concepts are the same, but Vectors just push everything to the most extreme level of difficulty beyond anything else in this hobby!
Yes, vectors can be a bit of a pain… they have so many quirks compared to other blasters.
Once you get around them though they are bad, just long winded. So many screws!
Certainly looks the business! I love seeing these gearboxes getting used, makes me grateful I went through many months of testing, and even more grateful MK Tactical stuck at it and brought it too reality!
A couple of tips for you @Roo
Heatshrink and insulated wires and solder joints on switches… there is a lot of potential for shorts with the metal gearbox!
Install the outer barrel when assembling the front section of the gearbox… I found the thread to be VERY tight… to the point I could not get the outer barrel threaded all the way once it was together. Also having the outer barrel in when assembling well help keep the inner barrel and tpiece aligned with the nozzle better… common area of seal loss in vectors.
Also… this is getting me… motivated to buy another one… I have two vectors, one has the MK box. I mean another vector, and two MK boxes! lol
Morning fellas!!
Today I finally put my vector all back together, I did in fact put some heat shrink on the wires in the gear box how ever I fear that it may not have me enough… or I have bigger problems
The gun was getting around 250fps but I was using the stock spring and it’s also quite a short barrel so if I want more it can be easier fixed
The mosfet however is a different story
One and a half mags later the vector mosfet decided to turn into a cloud of smoke so it looks like I’ll be getting a new one of them, any recommendations?
I’ll probably also end up upgrading all the wiring with some stuff from the auto electrician work, better insulation ect…
But for when the gun did run I was very impressed with it, trigger response was a lot better then expected and shot quite accurately aswell, cycled very good too.
Anyways here a pic of the KV rn, just waiting for a mosfet
