Gecado (Diana) Mod. 22 in .177

[grmkc]

Hey Shaz. Unless you're sentimentally attached, go with the latter.

[LWR58]

Do you still have the original piston seal?

Is the nylon one sealing in there?
Sounds like it isnt

They’re a nice little airgun


I may have one for you

A new Maccari spring is $25 posted

What grease are you using?
I can include some for you

Lewis

[shaz_au]

Thanks for the replies guys.
Grmkc; no there's no real sentimental attachment. Have you had a play with the panther? looking for something, small light, easy to cock and quiet.

LWR58; yes, but if you have a look at the pictures, the original seal is completely shagged. I'm using Abbey Gun Grease LT2 as recommended by the Airheads here.

[LWR58]

Grease is good but you really need a new spring!!

[LWR58]

I can supply a new Maccari spring for $25 posted

[fenring]

I had one of these as my first air rifle.

Hi Lewis!

[shaz_au]

Obviously I am a sucker for punishment, I ordered a new spring from Lewis just before Christmas but it is yet to arrive. I had some time this morning so I knocked this up:

Velocity wise there has been no change. I'm confident that this piston is sealing well so the breech seal must still need a tweak as the velocity is still lower than before I changed it.

[LWR58]

Oh no!!!
That should have been there ages ago

Please let me know if you don’t receive it this week with NY and all

I personally posted that to you

[LWR58]

Nice work on the piston!

If you’re happy it’s sealing well
The new mainspring should work a treat

If it’s not sealing the mainspring won’t help at all

The secret to airgun tuning is the piston seal not the spring


I threw in an assortment of O rings to try in the breech

[mattw1]

Your a man after my on heart with the retro-fit O Ring piston head.

I try to make mine as short on the nose end as possible to eek out every last drop of swept volume.

Cracking wee guns the older Gecado / Diana's

[shaz_au]

Thanks Lewis, I made a trip in to see if the spring was there, sure enough it was! A big thank you for including the diagram and some o-rings to try for the breech. The spring is waaaay longer ~250 vs ~178, has the old one really set that much? The wire size, outside diameter and number of coils are all about the same. I thought I better ask before I try to make it fit

Hey Matt, good to see you back on the forum, grmkc is still here too but I hadn't seen any posts from druid or yourself when I finally checked back in. Half the fun (and a good deal of the frustration) is in the tinkering with things I decided to stick with the same overall piston length this time around, I have other airguns if I want something more powerful. I'm really enjoying the smaller size, weight and easy to shoot nature of this old girl, so much so I'm thinking I might sell some of the big heavy things!

Cheers

[LWR58]

That’s great!!

I’m not surprised the new spring is much longer

Remember it’s the number of coils and the wire thickness
The length is irrelevant

Gecado springs were never flash
I remember changing all my Gecado springs on a regular basis

That spring will be tight on the guide

[shaz_au]

Wow, now that's a super speedy reply, I'll have a go and let you know how I get on.

Here is where I took the inspiration from for the new o-ring piston retrofit: https://www.tapatalk.com/groups/yellow/ ... 76587.html

[LWR58]

Thanks!!

I’ll have a read of that later

Just cleaning my car at the moment

[shaz_au]

Old Vs New

you weren't kidding about the spring guide being tight, I managed to squeeze one end on though.

That's some serious preload!


I can't get it together, no I don't have a spring compressor; I'm using the board on the gut method and with all my strength I'm still at least an inch off of where I need to be I know I'm not He-Man but even still that seems like a lot!?