[airsoft_robin]

I have a PDI hop up chamber with PDI w-bucking and I really want to flat hop my gun. But I'm not sure how good it will work with the PDI double hop up arm?
Right now it overhop a lot even if I have it on the lowest setting and I think that a flat hop will solve that.

Please help :bow:

 

[1tonne]

Reliku may be able to help you. He has a PDI hopup chamber that he has modded.

 

[Reliku]

Haha, cheers for the heads up.

I have a JJ (PDI clone) hop chamber in my type 96. I've got an R hop in it now but I used to have a flat hop. What I did was making a double tdc mod to get rid of PDI's unconventional system. By adjusting the thickness of your flat nub you can solve the overhop issue (you'll need a custom nub, pencil erasers work great here) and with a TDC mod you can adjust the hopup very well.

The airseal could be better but overal it's a great system, I'd definitely recommend the flat hop. Just make your bucking flat, put an eraser flat nub (a perfectly straight cut piece of pencil eraser that fits in the nub window) in there instead of the nornal nub and assemble the rest as usual.

The tdc mod just involves getting rid of the large O ring, the spring, the two hex screws you used to adjust the hopup with and just doing a tdc mod as usual, but twice next to eachother. Mine looks like this:

 

[airsoft_robin]

I can't see the picture :shrug:

TBC like this? But one for each arm:

I think I get it but I wonder how the hop up arms won't be pushed down to much? Original the hex screws make so the arms don't get pushed down but now when you remove them, what hold the arms up so they don't push to much on the nub? Are the arms lying on the nub or what? Do you get what i mean?
One more thing, how do you do when you apply the hop? Do you just put the arms so the apply the same amount of hop (so the arms are in level with each other) or how do you do?

 

[Reliku]

Here's the picture link: http://s26.postimg.org/9m8faqp2w/DSC_0044.jpg

Yes, you remove the screws inside. The screws on top determine how much hop is applied, they push the arms down.

When I apply hopup I apply both at the same time until I reach the desired amount of hopup. I then finetune it by giving one arm more or less hop so the end result means you get a perfectly straight flight path

 

[airsoft_robin]

As you see on this picture, Gyazo - 6563f80d48771e21b76a431333e1dbe6.png , the arm is hanging freely when the hex screws are gone (the yellow on the picture) and when you push down the screw the arm will have no resistant besides the nub, shouldn't I put something who prevent the arm from hanging freely on the nub? like a little spring or something (the arrow pointing on it in the picture).

And whats the 3:rd nut for? (pointing on the picture)
Gyazo - dc5d5a28f3dcae80dcb533097e8df5b2.png

Sorry for asking so many questions

 

[Reliku]

The bucking will keep itself into place. You do not have to keep the arm pushed up, the bucking will take care of that. Pushing it down is enough

The third nut is for my previous hop chamber (airsoftpro.cz chamber) which used a single arm setup. It had a single TDC mod, and I keep the nut there (covered with electrical tape) just in case I'll ever install a standard-shape chamber again. It's not used for the PDI chamber

 

[airsoft_robin]

okay, thank you very much. I think I can flat hop it now

 

[mintenjonathan]

Hi Reliku,

Ik ga even door in het Nederlands (als dit toegelaten is van Forum).

Ikzelf heb zonet een pdi hop up chamber besteld. En ik vroeg mij eigenlijk af waarom je de chamber hebt aangepast met "double tdc mod"? Is het standaard systeem van PDI moeilijk te gebruiken of werkt het gewoon niet goed?

Ikzelf heb redelijk veel ervaring met flat hop in AEG. Maar niet in sniper modellen.

Is prometheus purple goede bucking voor sniper +/-500fps? Die "pecil erasers" is dit 1 lang stuk dat onder beide hop up levers hangt? of 2 aparte stukjes? Heb je deze vastgelijmd of hangen ze gewoon los?

Hopelijk kan jij mij verder helpen. (If it's necessary to switch over to english i'll do)

groeten

 

[Reliku]

It is indeed a forum rule that you have to post in English. It's also a forum rule to make an intro post by the way, here are the rules

http://www.airsoftsniperforum.com/23-updates-support-feedback/176-rules.html

But no worries, I'll PM you an answer in Dutch

 

[mintenjonathan]

Hi Reliku,

Right now we are a few months further and I am struggling with fine tuning my PDI hop up unit. I cant give enough hop (allready filed down the screws for adjusting the hop), installed High hop up bars. I use it with PDI W bucking. and standard PDI bucking

So now the next step is to instal TDC mod. But i want to do a double TDC mod. One for each arm, so i can still adjust left/right deviation separately.

Last time we emailed with each other you told me that you also have double TDC mod for PDI hop up unit.

Is it possible to send me a picture of your mod? After TDC, are you happy with the result?
Do you use another bucking/nub in combination with your TDC mod?

Sorry for all the questions

Grtz

 

[Reliku]

A TDC mod is the best solution for this chamber in my opinion, I'm pretty convinced your problem will be solved after that. Here's a picture of how I did it:

It's pretty straightforward, just two TDC mods as usual but with small M2 screws instead :tup:

I've used this setup along with a flat hop (guarder black bucking + DIY nub) and it worked very well. I've sold it recently because I prefer VSR's but it's a solid setup

 

[Plazmaburn]

Your picture does not show.

 

[Reliku]

How come it doesn't? It shows perfectly fine for me :shrug:

http://s26.postimg.org/lo3t4vybb/DSC_0044.jpg

 

[Razinger]

Doesn't show on mobile but it should show for computers.


Razinger | The one, The only..

 

[Plazmaburn]

Fixed it. Bad image code.

 

[Reliku]

Sorry, may have done something wrong :shrug:

It's showing two images for me now :hehe:

 

[Plazmaburn]

Dunno. It is not showing any code or anything for a second image. Only the one I did. :shrug:

 

[mintenjonathan]

Thx Reliku.

I can see 2 pictures. and it all makes sense.

I'm going to give it a try :cheers: