Conical Spring as Sorbo Pad/Damper.

[Zigey]

Right, I'm well aware I'm opening myself up for ridicule for this but has anyone heard of useing a conical spring in the inside of an aeg cylinder head in an effort to slow the piston down and reduce the smacking sound?

The springs themselves come in just about any configuration you like and some can be compressed flat. 

I welcome any experiences/ideas/insults. 

View attachment 63978

 

[Sitting Duck]

Just NO

Sorbo, silicone or a braked piston head to reduce impact

are about the only real options

The thought of a tiny spring versus the main spring

How will it be affixed and the damage it will cause if it shifts out of position

The design of AEG's is extremely crude & basic

But also so is the wheel

 

[Zigey]

The way I imagine affixing it is to remove the rubber pad on the inside of the cylinder head and have the OD of the base of the spring sized so it gives a nice pressure fit with a few drops of hot glue just to be secure.

It's only ever going to be pushed back into the cylinder head so if installed correctly I don't see it coming loose, however if it did the worst that could happen as I imagine it is the piston not resetting correctly causing the teeth being chewed up and possibly a scratched up cylinder. 

It is the kind of simple idea that someone must have come up with before but Im not seeing anything on Google. 

 

[Adolf Hamster]

i'm with duck on this.

the reason to put anything inside a cylinder is to adjust the aoe (hear's luke ree-ing in the background). a spring heavy enough to arrest the piston is also going to play merry hell with engagement and you can kiss goodbye to your piston

if you want to eliminate the "pop" of firing then you're better of looking at a longer barreled build and using conventional silent type piston heads.

of course there's a limit to how far you can go with an aeg if your goal is silence, and you may be better off considering other options like hpa or a nbb pistol (mk23 being the obvious candidate)

personally, i'd rather an aeg have quiet gearing than reduced pop, even with the ultimate silence offered by an hpa you're still going to lose your position to folk respawning who know where you are.

 

[Zigey]

I agree with both of you, however I think the issues you have listed can be overcome. 

As to the "but why?..." I can only really say science. 

I started thinking about this because the piston slap I'm dealing with is exceptionally violent and I want to spread out some of the forces with the aim of longevity. 

Any conical spring would have to be compressed flat by the resting force of the main spring (sp100 is about 25 N/mm)to avoid AOE problems, this could potentially mean that any brakeing force provided would be so negligible as to be pointless. 

 

[Sitting Duck]

Google: " Bye bye sorbo "

on some sniper forum

for silicone pad on cylinder head

Or

View attachment 63988

The issue with the SLAP is piston hitting a very hard neoprene pad

Which be be a very loud or pronounced SLAP if head & pad are both hard & flat,effectively creating more of a CLAP

A braked piston head like above might cause issues in very high rof guns

But not so for slower rof guns like DMR's

In snappier guns the classic soft mushroom heads are maybe better suited

View attachment 63989

Or you can experiment and create your own type of braked head

I've used the domed silicone cylinder head

With a more curved Cyma piston head etc...

Sorbo MUST be topped off with at least 2mm neoprene

or it will just shred itself to bits in use very quickly

The sound is only part of the problem...

The actual energy transmitting to the box long term is the real issue for me

and why personally I prefer to use plastic cylinder heads

though the difference is negligible perhaps but in my mind the plastic may not transmit the impact quite as much as an alloy cylinder head

Though they are rubber cushioned heads etc...

All this Airsoft tech crap is often our own personal theories and preferences to be absolutely honest

Actual real scientific engineering studies are few & far between on toy guns

So we tend to roll with what WE ourselves think works best for US

The debates continue over correcting AoE & how much...

If PTFE actually works or if it is a bad bodge

(it fucking works if done correctly but if done poorly it is a bad bodge, it is still a bit of a bodge but it does work if done properly)

I don't always agree with everybody on everything

And vice versa some may disagree with me at times

We do shit to our OUR OWN personal preferences

and our methods & techniques are constantly being reviewed on their effectiveness etc...

Or they should be, I do shit a little different to what I did day 2 years ago and quite different to what I did day 6 years ago when I first went peew peew

If you think the conical spring had merit then go for it

But you asked for opinions/thoughts

So I responded

As said by all means give it a go, report back

But many will sceptical and you are introducing potential issues imho if spring works loose...

Ask anybody with a bearing piston head, that worked loose and destroyed their box. Despite it being tightened up to the max

(Threadlock required - but I personally don't use bearings on piston heads)

No, like the example given, I keep stuff simple

(Bit like the wheel which we tend to not try to reinvent)

 

[Zigey]

Google: " Bye bye sorbo "

on some sniper forum

for silicone pad on cylinder head

Or

View attachment 63988

I've seen those and I don't know how effective they are but I like the idea behind the tech, my cylinder head is asymmetric so these "airbrake" heads won't work.

As for a silicone pad I think they could behave strangely with the uneven loading. 

I have a spare gearbox so I think I will have a bit of an experiment. 

View attachment 63990

 

[Sitting Duck]

I've seen those and I don't know how effective they are but I like the idea behind the tech, my cylinder head is asymmetric so these "airbrake" heads won't work.

As for a silicone pad I think they could behave strangely with the uneven loading. 

I have a spare gearbox so I think I will have a bit of an experiment. 

View attachment 63990

Then your option is a sorbo pad topped with 2mm neoprene

Punched off centre to match the v7 type cylinder head etc...

Sorta custom scatterplot pad...

View attachment 63992

But make your own up

You could buy say a 22mm silicone pad/disc/blank washer

Then punch your own hole say 7-10mm hole

Or sorbo feet for hifi sound - solid sorbo discs on eBay

But ensure you top it with robust neoprene pad

At least 2mm thick, 1mm doesn't last I found

Somewhere say 20-22mm diameter, about 3mm thick

Re-use old pad etc... Cleaned up surface

(Washing up liquid suds, score surface & super glue it together)

That is about your best option to try than go down spring route just yet

 

[Zigey]

Then your option is a sorbo pad topped with 2mm neoprene

Punched off centre to match the v7 type cylinder head etc...

Sorta custom scatterplot pad...

View attachment 63992

But make your own up

You could buy say a 22mm silicone pad/disc/blank washer

Then punch your own hole say 7-10mm hole

Or sorbo feet for hifi sound - solid sorbo discs on eBay

But ensure you top it with robust neoprene pad

At least 2mm thick, 1mm doesn't last I found

Somewhere say 20-22mm diameter, about 3mm thick

Re-use old pad etc... Cleaned up surface

(Washing up liquid suds, score surface & super glue it together)

That is about your best option to try than go down spring route just yet

Thanks for your wisdom Duck, I highly doubt my spring idea will work (otherwise it would have been done already) but I can't leave well enough alone. ?

The sorbo pad topped with neoprene sounds like a winner, ill pick up some for when I come to my senses and drop the spring idea. ?

 

[Lozart]

Thanks for your wisdom Duck, I highly doubt my spring idea will work (otherwise it would have been done already) but I can't leave well enough alone. ?

The sorbo pad topped with neoprene sounds like a winner, ill pick up some for when I come to my senses and drop the spring idea. ?

Or you could just buy a premade one from Airlab https://airlab.parts/collections/gearbox-parts/products/sorbothane-pad-70d-hardness

 

[Samurai]

View attachment 63988

Don't do this. I've bought one and it indeed seals perfectly, meaning the piston head stops way before the impact, because the front O ring traps the air. The next cycle will destroy your piston or gears.

Remove the small O ring and it might work as an airbreak.

I don't like sorbo, it's still not very quiet. The way I tested materials for this is that I got a hammer out and hit it on a workbench. Just a small hit with the hammer from around 20cm high. Not forceful. That's about the force and impact area of a piston. The one that absorbed the impact the best was some very dense foam of a sanding thing. About 5mm thick. I glued it on the cylinder head I think in place of the rubber thing and it's super quiet.

 

[Rogerborg]

has anyone heard of useing a conical spring in the inside of an aeg cylinder head in an effort to slow the piston down and reduce the smacking sound

Naysayers will always say nay.

I say that if you understand the potential consequence, do it.

Why not?  They're toys, to have fun with.

If you get pleasure from the experiment, even if it kersplodes, that's a win.

And if by some miracle it actually holds together, imagine the "Well, well, well" dance of triumph.

 

[dagga333]

Samurai any chance you got more details on that dense foam? I’m really interested in if it’s suitable longish term. I’m just about to kick off a project build with one of the key aims to be as quiet as possible. 

 

[Samurai]

It's still on there. Just clean the surfaces with alcohol and use some nice superglue, like loctite.

 

[dagga333]

Any chance you got a photo of the Sanding thing?  

 

[Samurai]