Sounds like you finally got her figured out.
You got her figured out as soon as I got my rifle sold
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You got her figured out as soon as I got my rifle sold
PDI hop up adjustment screws
41 - 60 of 126 Posts
Double post, but yet another update.....Is anyone even following this anymore ???
Anyways, I am still tinkering with my PDI hop up chamber. Here are some things I have done/am going to do tonight.
1. Switch buckings: Going with a G&G
2. Wash bucking in soap and water: Its all clean and ready to go!
3. Make spacers for the side of the hop up arms. Woogie, I am sure you have noticed the hop up arms move around alittle even when put in place. I took some packaging that my bucking came in and glued in on the side of the chamber with Elmer's glue. Its drying now. Should keep the arms in there nice and tight. Which theoretically, should prevent the nubbin from also sliding around with the arms.
4. Cutting up the PDI nubbin and using it as a spacer for my prommy nubbin. Should keep the nubbin in place nice and tight.
5. Teflon tape the hop up screws.
Hopefully this will help solve the problem. I love the PDI hop up chamber, I can tell even from the crazy shots, that with some work, I could be slinging plastic a long way. :
Anyways, I am still tinkering with my PDI hop up chamber. Here are some things I have done/am going to do tonight.
1. Switch buckings: Going with a G&G
2. Wash bucking in soap and water: Its all clean and ready to go!
3. Make spacers for the side of the hop up arms. Woogie, I am sure you have noticed the hop up arms move around alittle even when put in place. I took some packaging that my bucking came in and glued in on the side of the chamber with Elmer's glue. Its drying now. Should keep the arms in there nice and tight. Which theoretically, should prevent the nubbin from also sliding around with the arms.
4. Cutting up the PDI nubbin and using it as a spacer for my prommy nubbin. Should keep the nubbin in place nice and tight.
5. Teflon tape the hop up screws.
Hopefully this will help solve the problem. I love the PDI hop up chamber, I can tell even from the crazy shots, that with some work, I could be slinging plastic a long way. :
fuzzywolly, glad you posted. I was going to start a thread for my mod but I will post it here. I think a general "PDI hop unit fixes" title is needed. Just a thought.
So we all know how this unit works or is supposed to work. It would be safe to say that the PDI hop unit takes time to set up properly. I had an idea and this is my modification to the unit. Testing will be done over the next month.
Every hop unit that I know of works with (1) lever/arm that pushes down on a nubbing which in turn pushes down on the hop bucking, then on to the bb. I took the basic operation and applied it to the PDI unit.
I eliminated one lever and centered the remaining lever in the unit, therefor creating a somewhat standard hop unit.
Materials used were a small portion of aluminum tubing and a piece of sheet metal to make the (T bar) and (nub cradle shim) pictured.
I used 5 minute epoxy to attach the T bar and nub cradle shim.
I trimmed the grub screws down by 1.5mm. Reason? I use .43g bb's and needed the arm to engage the bucking more. As most of you know, when you back the hop adjustment grub screws out (more hop), you can block the nozzle from going forward. Possibly damaging the cylinder head/nozzle.
I have pre set the depth of the grub screws in this photo so that I know that the "T bar" will be level when adjusting hop. I will make 1/8 turn adjustment or less in order to achieve my desired hop setting. *crossing his fingers.
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I also use Blue Loctite to keep the screws from backing out. Works great and I have never had a screw back out from using it.
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Arm and T bar plate sanded and cleaned. Ready for assembly.
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Aluminum tubing marked and ready for cutting.
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Here you can see the nub cradle shim installed. ***I may have to remove it if it creates to much hop.***
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Here you can see the (red) spacers on each side of the Prometheus nub in order to center the nub.
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Installing the unit in the outer barrel. I used aluminum tape to hold the spring in place while sliding the hop unit into the outer barrel.
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Shooting results coming soon.
So we all know how this unit works or is supposed to work. It would be safe to say that the PDI hop unit takes time to set up properly. I had an idea and this is my modification to the unit. Testing will be done over the next month.
Every hop unit that I know of works with (1) lever/arm that pushes down on a nubbing which in turn pushes down on the hop bucking, then on to the bb. I took the basic operation and applied it to the PDI unit.
I eliminated one lever and centered the remaining lever in the unit, therefor creating a somewhat standard hop unit.
Materials used were a small portion of aluminum tubing and a piece of sheet metal to make the (T bar) and (nub cradle shim) pictured.
I used 5 minute epoxy to attach the T bar and nub cradle shim.
I trimmed the grub screws down by 1.5mm. Reason? I use .43g bb's and needed the arm to engage the bucking more. As most of you know, when you back the hop adjustment grub screws out (more hop), you can block the nozzle from going forward. Possibly damaging the cylinder head/nozzle.
I have pre set the depth of the grub screws in this photo so that I know that the "T bar" will be level when adjusting hop. I will make 1/8 turn adjustment or less in order to achieve my desired hop setting. *crossing his fingers.
I also use Blue Loctite to keep the screws from backing out. Works great and I have never had a screw back out from using it.
Arm and T bar plate sanded and cleaned. Ready for assembly.
Aluminum tubing marked and ready for cutting.
Here you can see the nub cradle shim installed. ***I may have to remove it if it creates to much hop.***
Here you can see the (red) spacers on each side of the Prometheus nub in order to center the nub.
Installing the unit in the outer barrel. I used aluminum tape to hold the spring in place while sliding the hop unit into the outer barrel.
Shooting results coming soon.
13
Update!
While putting my rifle together, I was working with the hop up chamber and noticed something very important. When putting the large o ring over top of the hop up arms, I noticed that it causes the right hop up arm to slightly stick up. I tried adjusting the screws to get the right hop up arm to go down, but no matter what I did, which way I turned, it still remained higher up than the left hop up arm.
This is the problem. I had been looking in the wrong direction all along. Think about it, the right hop up arm sticks up at times, and other times it goes in the right position. It causes what I call the sparatic shots. So basically, I can get a good shot off here and there, but most likely the arm will reposition into a awkward place, giving me the right curves.
So what do you guys think I should do? I have been using filter wire to keep the arms together, instead of the small piece of metal that is supposed to be used (cause I lost it). I think the wire is alittle uneven, causing the arms to not be level with eachother. Any ideas?
Edit: Found out that the large o ring was not applying enough pressure to the arms. This was a part of the problem. Replaced it with a rubber band. The mods I have now are...
1. Tape the arms together
2. Rubber band replaces the o ring
3. PDI nubbin cut up as a spacer for the PCS nub
I am confident this should work. :
While putting my rifle together, I was working with the hop up chamber and noticed something very important. When putting the large o ring over top of the hop up arms, I noticed that it causes the right hop up arm to slightly stick up. I tried adjusting the screws to get the right hop up arm to go down, but no matter what I did, which way I turned, it still remained higher up than the left hop up arm.
This is the problem. I had been looking in the wrong direction all along. Think about it, the right hop up arm sticks up at times, and other times it goes in the right position. It causes what I call the sparatic shots. So basically, I can get a good shot off here and there, but most likely the arm will reposition into a awkward place, giving me the right curves.
So what do you guys think I should do? I have been using filter wire to keep the arms together, instead of the small piece of metal that is supposed to be used (cause I lost it). I think the wire is alittle uneven, causing the arms to not be level with eachother. Any ideas?
Edit: Found out that the large o ring was not applying enough pressure to the arms. This was a part of the problem. Replaced it with a rubber band. The mods I have now are...
1. Tape the arms together
2. Rubber band replaces the o ring
3. PDI nubbin cut up as a spacer for the PCS nub
I am confident this should work. :
Well it will work untill you shoot it
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Have you thought about getting attaching a small spring to the back side of the arms? Then you wouldn't need to use the large o-ring at all.
I can't remember if there would be enough room or not. If not you could always sand down some groves in your outter barrel for them to work.
Have you thought about getting attaching a small spring to the back side of the arms? Then you wouldn't need to use the large o-ring at all.
I can't remember if there would be enough room or not. If not you could always sand down some groves in your outter barrel for them to work.
fuzzy, Good find on the arms binding because of the O-ring. That makes so much sense. What about this?
I picked up a stiffer spring then the one supplied with the PDI hop unit. I think the stiffer spring by it's self has plenty of down pressure on the arms. Maybe try just using a spring only and not the O-ring.
In my application it should not affect the arm.
"Installing the unit in the outer barrel. I used aluminum tape to hold the spring in place while sliding the hop unit into the outer barrel."
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I say this because my FF Aero Chamber for my aps2 sv uses just a single "leaf spring" design to hold the arm down. It works perfectly.
I picked up a stiffer spring then the one supplied with the PDI hop unit. I think the stiffer spring by it's self has plenty of down pressure on the arms. Maybe try just using a spring only and not the O-ring.
In my application it should not affect the arm.
"Installing the unit in the outer barrel. I used aluminum tape to hold the spring in place while sliding the hop unit into the outer barrel."
I say this because my FF Aero Chamber for my aps2 sv uses just a single "leaf spring" design to hold the arm down. It works perfectly.
Thanks for the tips and advice guys. Using dagger's picture above for reference, here is what I did:
1. The back of the arms would wiggle and one would slightly pop on top of the other. I used some tape to tighten them together, so neither one could slightly be pushed on top of the other.
2. The rubber band has applied soo much more pressure to the arms. When the hop up screws are adjusted, the arms move and stay put (do not wiggle around up and down.). I have high hopes for this. If it does not work, I will give what you guys suggested.
And yes woogie, my rifle always works before I shoot it.
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1. The back of the arms would wiggle and one would slightly pop on top of the other. I used some tape to tighten them together, so neither one could slightly be pushed on top of the other.
2. The rubber band has applied soo much more pressure to the arms. When the hop up screws are adjusted, the arms move and stay put (do not wiggle around up and down.). I have high hopes for this. If it does not work, I will give what you guys suggested.
And yes woogie, my rifle always works before I shoot it.
Heck with all of these mods... I may not want to get out of airsofting.....
May have to grab a chepo and build it up.
I hate all of you so darn much
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May have to grab a chepo and build it up.
I hate all of you so darn much
Haha, I vote for grabbing a cheapo and staying in the game
You could probably go with an ASR Woogie, small little gun but it takes APS-2 parts; a definite plus. Or go for a nice DMR
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... Or one of mine
How is the unit working now fuzzy?
How is the unit working now fuzzy?
Have not tested it out yet. Will let you guys know how it goes when I finally dosoldierofvalor said:... Or one of mine
How is the unit working now fuzzy?
.
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