Stug III recoil
 

Hi guys just taken the recoil apart to see if its posible to get it working correctly and the answer is I think it is the recoil unit motors back then springs forward well Have a look at photos the gear that winds the barrel forward needs a slight modifiction one is to stop it going all the way back so the gear can engage the other is to modifie it so it moves a little further forward so the gear will disengage this will allow the gun to recoil then reverse the motor conection so its running backwards so when you hit the fire button the motor will turn to disengage the barrel the spring will pull the gun backwards then the motor will engage and push the barrel forward.

I think it will need filing where the screwdriver is pointing in 4 places
will try tommorrow and let you know

RE: Stug III recoil
 

Nice one, please keep us posted on this mod. All the best for now
Alan :D

RE: Stug III recoil
 

Looks interesting...This would be a really nice improvement.

D.

RE: Stug III recoil
 

Hi Dave got it to work spring back and motor forward looks better but will need to fit limit switch to stop gun when it returns to normal length I Have a small micro switch just have to work out how to wire it .

regards pete


the mechanics were easy its the electrics that leave me stumped

RE: Stug III recoil
 

You might use the same principle as Asiatam's recoil units: use a normally closed switch which replicates the negative connection of the recoil motor, and connect it directly to the battery negative. Put the switch as to open it when the barrel is back in resting position.
That way you just need a short current pulse to move the last gear, disengage the barrel theeth making it spring back, and close the switch. The closed switch will continue feeding the recoil motor, making the last gear engage the barrel and move it into resting position, at which point it must open the switch, stopping everything.

RE: Stug III recoil
 

Hey Pete well done for daring to delve into the recoil unit. What you suggest seems to make a lot of sense. Between you and borealis you should get a fix working there.

p.s. Did I see a pic of the stug recoil unit that showed a spring loaded switch already in there ?.

NIck.

RE: Stug III recoil
 

Hi Nick the orginal recoil unit works backwards winds back with motor then springs forward so with a little bit of filing to the stops inside the unit turn wires round on motor change spring round 180 degrees now just to sort limit switch wiring it springs back and motors forward stops at end of stroke just to sort out pluse to start it.
Had to take it out to fit focus tube for I.R to make sure the range and direction are right so thought I would see if I could mod the recoil once this is done will put it to one side till I do the schurzen then going to have a look at my Panzer4 fit a modified BB gun changed it to recoil fit this then a new barrel got plans from Septon today so can make one now then schurzen for both panzer 4 and stug III.

regards pete

RE: Stug III recoil
 

Pete, I just thought. Couldn't you use a 3.5 mm stereo jack socket as a limit switch. Do you get my drift i.e. going open circuit at full forward position.

Just a thought.

Nick.

RE: Stug III recoil
 

Hi Guys just to let you know it works after Darkith told me how to wire the limit switch now I have a proper recoil in the stug III it as spring to pull it back and motor to push it forward in other words fast bark slow forward will post pics tommorrow of how to do it .the hardest part is setting the micro switch there is not much to do just remove about 1,5mm from internal stops to allow barrel to slide a little further forward turn spring around so it pulls in opposte direction swop wires on motor to change direction of motor and add a wire from micro switch to battery negative.


regards pete

RE: Stug III recoil
 

How's it working mate. Have you got any new pic's yet.

Nick.

RE: Stug III recoil
 

Hi Guys its finished and tested works fine the only filing to do is the internal stops pointed out with screwdriver on early post you have to file about 1,5 mm off 4 stops to allow the barrel to move forward to disengage the drive gear,glue the clutch so it will disengage at end of stoke from a stationary postion when testing found the cluch would slip rather than disengage , after this swop over motor wires to reverse the motor move spring 180 degrees so it pulls the barrel backwards and fit limit switch to stop barrel when it is driven forward with the motor.The hardest part is setting the limit switch its alot of trial&error to get it just right

the wiring should be like this
Batt Positive connected directly to motor as per stock.
Batt Negative connected to NC on microswitch
COM on microswitch connected to motor
Recoil start/supply (negative) from RX18 board connected to NO on microswitch


if its worked you should see the new gearbox from Heng long its only the right one they have changed

regards pete

RE: Stug III recoil
 

Sounds fabulous Pete. I'm just struggling a bit with the nomenclature !!. "Com" "No" etc.
Mate keep it simple, remember I'm thick as mince.

Ta,

Nick.

RE: Stug III recoil
 

COM = Common pin
NC = Normally closed (connected to COM when the switch is idle)
NO = Normally open (not connected to COM when idle)

When the switch is activated, NO gets connected to COM, and NC gets disconnected.
On some switches they use the COM (or C), NO, and NC labels.
Others show a diagram imprinted on the side.

D.

RE: Stug III recoil
 

Got it Darkith...Thanks Pal.

Nick.

RE: Stug III recoil
 

Hi Nick If you do the mod read the other post I put on how to remove the barrel they have screws that are very hard to get at If you get stuck drop me a P.M and I will help all I can If need be will come over its only about 40 miles to your place.


regards pete

RE: Stug III recoil
 

Ok I'll try the right post this time...Sorry Debbie and I have just enjoyed a nice Rib-eye steak and wine !!!, so I'm a bit fresh !!.

Very kind offer mate...If you pop over and help me out then I'll put a nice bottle of Claret to one side for us to enjoy.

All the best,

Nick.