£50 project ICS MP5SD

[Just Joe]

Hey Team,

Bought myself an old ICS MP5. Pretty happy with the deal I got but wanting to tinker with it.
 

What I want out of it. A snappier trigger really. I put a 7.4V Lipo in there last night and it was rather sluggish, well very. But that's okay, I wasn't expecting much. 

My logic is to try and get this suitable for a 11.1V Lipo, I have loads of those that will fit therefore I don't have to factor this into the cost.

In order to do this I believe I will need/should have a mosfet. Now I'm not really after anything fancy, something no more then the £25 mark, taking up 50% of my budget. I've seen the Gate Nano Mosfet that has AAB, active breaking. Which I presume is going to help.

 

I think I know the answer, but do I need active breaking? Logic to me says so. 

 

Following this I was thinking just short stroking the standard gear set by 3 teeth, if someone could clarify if this should be done off the pick up release side that would be great.
Will need to then shortstroke the piston by the same amount of teeth, on the release side.

 

The rest of the budget will most likely go towards the hop up. Any suggestions for this? Maple leaf rubbers seem to the best but I'm having a tough time finding the macron rubber and nub both in stock. I'm thinking perhaps just a cheaper but none the less viable option. Having said this, I have yet to shoot into anything that isn't a cardboard box. 

 

Hopefully that will give me close to the results I'm after. I'm not really looking for anything mental.

 

I'll also be testing airseals, I have spare O-Rings should they need to be replaced. 

 

I've think I've read in the past about polishing the inside of cylinders... Any real need?

If you have any advice about low cost improvements I can do feel free to let me know.

 

I'll try and get a video of it firing at some point. 

At present, the estimate build cost is only £35.00 I'm going to see if I can get it performing better for that. Failing its still a bit eh. Would it be better to opt for 12:1/13:1 gears or a higher torque/higher speed motor?

 

TIA.

[Asomodai]

I would just get a better motor at this point and stick with 7.4v lipo. 

SHS/Rocket Green 16TPA should do the trick. 

[Just Joe]

16 minutes ago, Asomodai said:

I would just get a better motor at this point and stick with 7.4v lipo. 

SHS/Rocket Green 16TPA should do the trick. 

Just a direct motor replacement?

[Skara]

19 minutes ago, Just Joe said:

Following this I was thinking just short stroking the standard gear set by 3 teeth, if someone could clarify if this should be done off the pick up release side that would be great.
Will need to then shortstroke the piston by the same amount of teeth, on the release side.

I always remove teeth from the pickup side.

The thing is, there is already a very short time between the tappet plate (nozzle) release point and the piston release point, if you shorten that gap even more by removing teeth from the release side you'll most likely cause timing issues, where the piston is being released when the nozzle is still traveling forward, causing massive power losses and/or fucked up feeding.

Shaving from the pickup side will just delay the piston's engagement point.

 

Also no, you don't need to remove teeth from the piston rack, those last 2/3 teeth will never get used and shaving them won't save much weight either.

[Asomodai]

2 hours ago, Just Joe said:

Just a direct motor replacement?

 

Yup. It's a pretty good upgrade and may do exactly what you need it to do without opening up the gearbox. The stock Ferrite ICS Motors are pretty pants. 

[leadly]

Treat yourself to a dip into Alan's parts box and see what you come out with! 😂