Daystate Mk3 RT Battery Charging problem & Firing Valve leaks.

[Airsporter56]

Daystate Mk3 RT Firing Valve & Charging Problems

My Daystate Mk3 RT has been a collection of parts for about 18 months, until yesterday.
Before i stripped it down, it had a couple of issues; the batteries would not recharge and i had a persistent leak in the area of the regulator.

The battery charging problem was identified as a fault on the circuit board, but as Daystate varnished it at manufacture to keep the damp out, it’s subsequently very difficult to fault-find and even if i found the fault, the tiny surface mounted components are a swine to replace.

I ended up buying a 50ma regulated power supply and directly connected the 9.6 Volt battery pair to the charging socket lead, where it attaches to the circuit board.
The benefit of this is that i can check the battery voltage from the charging port.

The leak turned out to be the firing valve.
On the Mk3 RT, it is a two-piece valve with two halves butting together with tapered ends that were sealed by a hard plastic ring, that was no longer sealing very well.

The Daystate replacement seal kit contains no such seal, so i turned a piece of aluminium tubing down, leaving it with 2mm walls to form a loose push fit inside both halves of the firing valve and cut two 1mm deep slots at either end of the tube to take 1.5mm cross section O rings.
I assembled this with a Viton O ring in the middle to form a slightly elastic joint in between the two halves of the firing valve, to make it easier to refit the firing valve locating pins.


No more leaks!
Reassembled the rifle. Just an hour or so of checking on the Chrony at various pressures & regulator adjustment to confirm that everything was in order, legal & with a good spread of consistency. Seems like i now have a lot more shots per charge, with the reduced volume of the firing valve.


I’d attach a photo of a dismantled firing valve, but can’t seem to see an option to do it.

[Phil Russell]

Excellent information and very pleased you got it sorted.
Cheers, Phil

[Shed tuner]

awesome, always good to be able to DIY your way around problems. Interesting on the reduced firing valve volume giving more shots too... maybe the reg pressure was too high before ? Or is it possible that the smaller volume could be causing the post reg/plenum presure to remain a little higher, closing the valve faster ?

[Airsporter56]

awesome, always good to be able to DIY your way around problems. Interesting on the reduced firing valve volume giving more shots too... maybe the reg pressure was too high before ? Or is it possible that the smaller volume could be causing the post reg/plenum presure to remain a little higher, closing the valve faster ?

I’m a retired Aircraft Mechanical Engineer and Specialist Hydraulic/Pneumatic test equipment technician, used to work with pressures up to 100,000 psi (6800 Bar) in the case of some test equipment.

Can’t specifically comment on the firing valve volume reduction due to the group rules, but efficiencies have to be obtained. I 1st tested the rifle unregulated, so i could establish the ideal regulated pressure to set the regulator up.

[rapidresponse1]

well done and good info