Advice please on short stroking and premature engagement

[Sitting Duck]

It's fine - been there myself, steaming in, thinking this n that, trying to run before I can walk etc....

Oh it must be this, or OK I'll do this to compensate and before you know it, it is much worse than ever

 

Like I said my first couple of attempts were disasters

the next few were not much better but did work (for a while)

Then eventually learnt there is a bit more to this stuff than go faster motors, go faster gears and more juice

And there is so much to how it all carefully fits together exactly

 

Think this sort of sums up airsoft teching at times.....

 

[madmogga]

So I pulled everything apart again tonight, shimming was not good when I checked once everything was together two of the gears had zero play in them so stripped everything out again and started over. doing motor and bevel gear first. I did have a problem in that the height adjustment on my motor did not allow me to align the pinion and bevel so had to make a few adjustments to the motor cage. All shimmed a lot better and sounds a lot better although I still think it’s a bit noisy so maybe the shimming is still a little bit out. Popped it all back together with the 16:1 gears and the 40K motor no improvement on the RPS so I thought id check my lipo 3.5v/3.5v  wtf! I only charged it a week ago when I did all these mods and only been using it for testing 200 rounds max. I only had a half charged 9.6v with deans laying about so plugged that in and straight away sounded and ran better getting me 18rsp which I think on a 1600amp 9.6v half charge battery is a bit more like where I think it should be. Not sure if lipo is faulty or 3.5v/3.5v is normal after that short amount of use but am I right in thinking I should not run it down that much 3.8v minimum ?

 

why i never though to test the battery grrrr 

[Sitting Duck]

Lipo cells are 3.7v and can be charged up to a MAX of 4.2v

So a freshly charged LiPo will be 8.4v aprox

 

The cells have a charging range of 3.0v min to max 4.2v

above 4.2v per cell they are starting to overcharge and damage/deteriation may/will occur

if the cell drops to 3.0v or less some chargers will announce a charging error

this can sometimes be coaxed by slowly & lightly trickle charging the cells back above 3.0v

By then the B6 type charger should then attempt to charge the lipo as per usual

The cell(s) get charged up to 4.2v and balanced across the two/three cells which may equate to about 8.38v

In reality the cells may not be 101% balanced exactly but the charger attempts to balance the cells

(so don't panic if cell is 4.19v & other is 4.20v or 4.18v)

 

Cells can come off charge at a smidge over though they should not be much over the recommended 8.4v

(is your voltmeter 1001% accurate ???)

 

Rule of thumb - lipo's should be 8.4v max to about 6.4v or 4.2v per cell to 3.2v per cell

Often batteries get changed at lunch time anyway so they don't get too low and charge issues

 

(There are some newer ultra lipo's that can be charged a smidge more than 4.2v but usually 4.2v is the cell max)

 

Soon a fairly fresh 4.18/4.19v per cell lipo you rof should be XX rps

 

If your gun is still a tiny bit shrilly after checking motor height/bevel then it could be the motor angle

on a v3 with motor frame/cage if you slightly loosen the two screws on cage/box you should have a smidge of slack

by slightly altering the angle the motor meshes with the bevel you might be able to improve/worsen the gears meshing

(not a lot of slack but can make enough difference to quieten the gears a bit more)

[madmogga]

I thought I would post a quick update on the progress as I was still not happy with the motor height and my shimming and the RPS I was getting.

 

I purchased a new motor cage which is a lot better allowing for a lot more adjustment of the motor height, I also found the Action Army 30K motor meshed a lot better than the AEG boost 40k so rebuilt the gearbox with my SHS13:1 and the AA motor spending time doing the shimming (took me a good 2 hours) – put everything back together and gears now sound a lot better best I have ever had them, and I am getting a nice 21/22 rps which I am happy with.

 

Unfortunately, I now have other issues with the gun going into full auto while on Semi and the FPS down a bit but I think I know what these are, the semi auto issue I think is the gear shimmed a bit too high for the cut off level and the FPS drop due to the barrel / hop up unit not installed correctly –pushing the hop up in was a bit tighter than normal but as it was late I kind of just wanted to get it back together and test fire it so probably not aligned correctly giving an air leek ….

 

Nearly their ill sort the last few issues out tonight or tomorrow and hopefully will have a nicely tuned gun shooting just under my sit limit of 350fps  This was always just a project to gain experience an learn from mistakes and have really enjoyed getting stuck in, I have learned and gained a lot of experience especially with the help of this forum so a big thanks for all your help.