Removing Diana Original Cog Wheel Holders

[Mobiasstrip]

For many years I have struggled to remove the cog wheel holders on Diana Original Giss pistols and rifles. Wrapping with leather etc is always tricky and often still damages the knurled finish.
Today I spent less than £15 on a pair of Clarke soft jaw water pump pliers which transformed the job on a recently acquired Mod 6 that is in lovely condition - apart from the cheese texture seals….
Sharing just in case it helps anyone here. Probably the old hands have already worked it out :-)


Happy fettling
Steve

[Benelli B76]

Yes been using standard circular Mole grips with leather pads. Nice not to chew them up, but also can clean them nicely with needle files if someone
has butchered them.


Baz

[Mobiasstrip]

Now firing at 325 fps. The plastic grip Mod 6 is a bit of an ugly duckling compared to the 6m/6g or 10 but still a beautifully engineered pistol. Clever chaps those Germans. 1977 so a late model.

[ptdunk]

Good tip about the pliers, ta.

The plastic grips on the 6 are very ugly but ergonomically very effective.
I’ve got one in lovely condition that I still haven’t got round to resealing…one day…

Cheers,
Matt

[Mobiasstrip]

Knibbs still stock full set of springs and seals which is remarkable given age of pistol.
Some pics here.
https://imgur.com/a/7ggqume
Steve

[Mobiasstrip]

Model 10 getting the same treatment. Front and rear piston seals both were intact but cracked into pieces when removed. Cog wheel holders undid by hand!!!

Steve

[Mobiasstrip]

To complete the thread - some pics of Mod 10 reassembly.
The trigger is more difficult to put back together than the cogs and pistons in my opinion! Great piece of German engineering:-)
https://imgur.com/a/TXbTwvf

[abellringer]

I've lost count of the amount of chewed up pistols I've had for repair [rifles too]. These look a good option; however coming across so many problem ones; I've made up a jig which allows me to drill the cap with 2 holes same as on other Originals and then I use my 2 peg wrenches. Not something everybody might do, but I had access to toolroom equipment which gave me the chance to make lots of specialist tools. That said I'm still getting a pair of these and thanks for the heads up.

[Benelli B76]

Model 10 getting the same treatment. Front and rear piston seals both were intact but cracked into pieces when removed. Cog wheel holders undid by hand!!!

Steve

Are you also using a compression piston seal on the rear balance piston ?

Baz

[Mobiasstrip]

Are you also using a compression piston seal on the rear balance piston ?

Baz

Good spot Baz, the photo I posted shows two compression seals that I had already. Was awaiting the rear from Knibbs I think. Different colour for some reason. Here are the internals prior to assembly. Steve

[Benelli B76]

Thats better, the correct buffer seal which does not compress air in the rear chamber.

Baz

[abellringer]

Yes, I stopped using the "correct" seal when I realised they let the actual piston body run on the cylinder wall; as an engineer metal on metal isn't good.
The actual seal type makes no difference to compression because the rear piston has a hole in it, so vents to atmosphere, the rear piston doesn't run metal to metal, which I prefer. Have to say stunning photos though.