Cylinder length . Bit short?

Ok got an actual issue this time!

New cylinder , cylinder head, piston, head all same brand . Chucked into a gen8 skd ss box and it comes about 1mm shorter than stock and leaves a gap.

It also lets the piston head pull out quite far exposing the oring. Is this a problem?

Should I leave a gap at the front of the cylinder and cylinder head like the photo? Sounds like a shit idea tbh and wouldnt last too long. Though it has a bloddy good seal like this still lol.IMG_20200326_145320|690x388

Or even worse if i drill the holes on the side a little bigger in the cylinder head that homd it in olace it will go back enough but probably move around? If that makes sense.

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Hopefully better results when I put this in a jinming gen 8 box but doubt it.

Check with sector gear in. As soon as the ladder goes past last tooth on sector gear the spring will push it forward. Likely that will be well before the o-ring clears the cylinder

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Good point. Waiting in the next few days of the mail to get the 18:1s for this new box. Might just run the nylons through when i get home.

I say make the cylinder go fully to the nozzle end and do something to keep it there… the sector gear wont be able to pull the plunger back far enough to let the seal out… it will have let the plunger go long before that noidea

The sector gear will release the plunger about 30mm before the seal reaches the back end of the cylinder pop

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30 mm?


This where it gets to with stock internals

Push the plunger down til it stops… like the spring would do…

cylinder1

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The plunger would never get pulled back that far in operation…

I thought thats what i did in the (old) photo?
You just confused me. Ill check it again when im home.
From the last sector tooth contact on the ladder theres a few millimetres at most before spring will return plunger. Basically round abouts where it is in the pic.

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Picture the gearbox with the spring in it and the retainer holding the spring in place… the piston is all the way down the bore right at the cylinder head… the sector gear grabs the big tooth and pulls the plunger back against the spring until the sector gear runs out of teeth and lets the plunger go…pop

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Yeah i get that but the plungers let go when its right back like that no?

I often pull apart to find the gearbox didnt cycle and is all the way back like this

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15 teeth… If that matters

The plunger should be pushed completely in by the spring. If you are trying to cycle it without the spring in place, it might do that.

Never pull the trigger without the spring in place and the spring retainer in place or it will damage the sector gear and piston.

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Nah never ran it without the spring

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When you removed the spring it probably dragged the piston back with it

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With the plunger spring in place, the plunger could physically not come back that far… the spring would bind up and become solid way before reaching there…noidea

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Still confused. If it didnt go back as far as it did in the 1stnpic with the red trigger , it wouldnt be 100% use of the cylinder??

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Push the piston all the way in, then turn the sector gear slowly until the last teeth clear the ladder. That’s how far back it will go

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Watch this animation…

Notice with the spring in, the piston is fully pushed in whilst resting…

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Like ifbthe last sector tooth was the white triangle it would be where it is no?

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