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daniel k

Stampede mod problems.

Just finished rewiring my stampede, but when I pull the trigger...no darts come out. The gun cycles well, has a retal spring in. These are the internals:




SSGT

I don't know if you took it out for the picture but it's missing the drop down "dart tooth" (and spring) that holds the push-back gate closed. It also looks like it's missing it's main spring and end cap for the cylinder (possibly broken in the image - can't quite tell) .
daniel k

Catch spring is in, isn't that thing over the plunder rod in photo 3 the catch plate?
SSGT

Sorry, caught that but obviously not quickly enough - edited for the other things missing. The piston rod is sticking out of the cylinder too far which made me think it was missing the catch.
daniel k

NoticeNoticed the dart tooth ect missing, wasn't sure if that was the problem or not. The main spring is replaced with a Retaliator spring, the back plate was made out of spare parts as it was missing.
SSGT

Actually, looking closer, it looks like the whole pushback gate system (drop down "tooth" and swing door) is missing/broken. That is an issue as, without those, the dart won't be pushed back into the bolt - the bolt will just push it into the fluted barrel and won't fire it.

I'd say that spring is too short aswell (or there's an obstruction in the cylinder preventing the piston from moving all the way forward). At rest the catching surface of the piston rod should be pretty much level with the catch plate (shown here) otherwise most of the forward travel of the cylinder doesn't do anything to compress the spring.

EDIT: If that's a non-standard cylinder end plate it's also missing the little lug that pulls the catch release arm (the orange spring-loaded piece below the cylinder that slides back and forth) forward as the cylinder moves forward (also shown in the image above) - it won't be able to release the catch when the cylinder is fully forward.
daniel k

Anybody got a spare stampede dart tooth/door piece then? Will that be the problem? Also, will it work with only a dart tooth.
SSGT

You'll either need a replacement pushback gate assembly and cylinder end plate, or you'll need to make a sealed breech system (which removes the need for a pushback gate system completely) although you'd still need a new end plate with the latter (you might be able to modify a lug onto what's already there but you'll have to tune it so that the timing of the catch release is correct).

A "dart tooth" on it's own isn't enough in this case unfortunately, at least not without quite a bit of work (even then it'd be more prone to "top-hat" dart stoppages where the tip is bent down by the retracting "tooth" - that's likely why Hasbro moved away from that system and moved to this swing gate system).

As I said, it also looks like there's something wrong with the cylinder - either the spring is too short or there's something inside preventing the piston from moving forward fully. At best that'll rob you of potential power, at worst it could break something. That piston rod is sticking out of the back of the cylinder way too far at rest.

EDIT: Actually, it get's worse. It looks like you might also be missing the actuator arm (along with it's return spring and the cover plate) for the "dart tooth" aswell - it's meant to run along the right hand side of the magwell (covered by a plate) and is pushed forward by the cylinder, or the pivot that moves when opening the jam door, to retract the "dart tooth" when firing/when you open the jam door (there should be a similar actuator arm on the left side of the magwell that works with the other arm to open the pushback gate when you open the jam door, although that one is less critical - it will still work without it). If that's been missing for a while that would explain the broken pushback gate - the bolt moves forward and physically opens the gate, if the dart tooth hasn't retracted it'll simply break it off it's hinges. You might be able to fashion a new one out of a sheet of ABS but without it the new pushback gate will also destroy itself pretty quickly.
daniel k

I have spares of that bit, thank god, but the dart door bit is screwed. Hopefully someone has spares but if not I do a sealed/sleeper breach
OldNoob

First off, good luck making a working Stampede brass breech. There are 3 successful ones in the world AFAIK, the overlap for stock darts is right on the limit for a seal and they tear themselves apart in seconds.
Second- Stacked springs are a very bad idea in the Stampede. It is VERY picky about the stroke length and if you want it to work in any reliable way, a single CORRECTLY SIZED Spring is an ESSENTIAL.
Third- Not sure what the rest of the loom is like but I see what looks like hot glue on the cycle control switch, that is NOT a strong enough adhesive for that job and if it fails your blaster will over run and if the switch moves up and goes into the firing mechanism, especially under the moving plunger tube, you can kiss your gearbox or motor/loom goodbye. At the very least use a quality adhesive and I would add a fuse to the main battery +ve. 15A mini blade pops a little easier but 20A is a little on the high side, so depends on what Spring load you end up with. 6kg pulls 17-18A stall. Make sure your master arming switch is up to snuff or protect it with a MOSFET as well, then you can manually kill the power.

Now to the dart gate assembly- You will need a whole one of those, gate, tooth, Spring etc and it must be in really good condition or you will never get reliable power. I might have one, I can have a look.
daniel k

Thanks ON, I planned on using epoxy putty to fully seat it, hot glue was for testing stages. Are you saying to add a 18A fuse the the positive wire, and to wire up a kill switch? That's what I interpreted, but better safe than sorry, right? Also What fuse would you recommend for stock spring strength as well?
OldNoob

Stock spring- 10A, if that pops too often then go next size up. Fuse goes inline on the main battery +ve.
If you removed the main on off switch when you modded (current UK rewire keeps this, see BSUK wiring diagram) then use that, if not add one, either a 10A rated one or a small one protected by a MOSFET.
Clockwork Wino

Don't know if you've found the bits you need but I've just picked up a Stampede as part of a spares n' repairs bundle. Not sure what's wrong with it as I've not had chance to test it but since I only want the shell I'm happy to gut it and send you all the internals if that's a help.
daniel k

Thanks for the offer, UKNW is looking to see if he can help me out, but if he can't I would be very grateful.[/list]

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