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Drozd and Blackbird Discussion / Re: Steel gear replacements
« Last post by Westwind on May 22, 2017, 09:37:37 PM »East Milford I sent you a pm
Recent Posts
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Drozd and Blackbird Discussion / Re: Steel gear replacements
« Last post by East Milford on May 22, 2017, 06:49:51 PM »Now you are talkin' turkey. I want to see that thing whine at 6K. This is what 5K sounds like.
https://www.youtube.com/watch?v=T4hNz1l9usE
Hi Mason,
For the 6k i didnt use meshing gears. I used two cogs with a roller chain. I lost interest in the 6k, it was just superfluous in my opinion. It's so fast that it doesn't even sound automatic, its just a constant loud drone. I guess i prefer playing around with 2k the most fun. The velocity at 6k was stupid slow too. I had to use two separate hpa tanks fitted to one line to get enough volume to keep up with what the valve body can put out at those speeds.
Good luck with your 6k, im sure you will hammer it out soon enough.
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Drozd and Blackbird Discussion / Re: Steel gear replacements
« Last post by Parellax on May 21, 2017, 10:13:51 PM »Now you are talkin' turkey. I want to see that thing whine at 6K. This is what 5K sounds like.
https://www.youtube.com/watch?v=T4hNz1l9usE
https://www.youtube.com/watch?v=T4hNz1l9usE
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Drozd and Blackbird Discussion / Re: Steel gear replacements
« Last post by Westwind on May 21, 2017, 12:24:18 PM »Thanks for the great info.
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Drozd and Blackbird Discussion / Steel gear replacements
« Last post by East Milford on May 20, 2017, 10:56:37 PM »When using stiffer spring rates to achieve 2,4 or 6k rpm speeds the additional force that is applied to the clutch can prematurely wear out the pressure plate surface on the larger gear. This might not happen right away bit, if you like to shoot a lot of single fire shots the additional torque will cause quick wear from the clutch constantly needing to slip during singe fire modes.
So this is what i did to resolve the problem. Additionally it makes for a much smoother sounding operation and increased durability.
Replaced all plastic gears with hardened steel alternates.
The gears requires some minimal machining.
The clutch has been replaced with a carbon fiber unit that is twice as thick at 1mm. The D shaped anti-rotation bore is still applied to the clutch.
If anyone is interested in a gear set, or just a new steel drive gear for your upgraded motors you may send me a message and I'll gladly help you out.
Enjoy.
So this is what i did to resolve the problem. Additionally it makes for a much smoother sounding operation and increased durability.
Replaced all plastic gears with hardened steel alternates.
The gears requires some minimal machining.
The clutch has been replaced with a carbon fiber unit that is twice as thick at 1mm. The D shaped anti-rotation bore is still applied to the clutch.
If anyone is interested in a gear set, or just a new steel drive gear for your upgraded motors you may send me a message and I'll gladly help you out.
Enjoy.
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Drozd and Blackbird Discussion / Re: BB Feed Sleeve Mod.
« Last post by East Milford on May 12, 2017, 02:21:42 PM » Feed tube with the complete assembly. The air tube to air adapter is ported out, the factory port is the size of a pin, I enlarged it to 5mm then TIG welded the joints.
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Drozd and Blackbird Discussion / Re: Volumetric efficiency mod.
« Last post by East Milford on May 12, 2017, 02:18:50 PM »More pics of the complete assembly. Barrel to mag face mod, BB feed tube mod,
Ported and sealed air adapter to air feed tube.
Ported and sealed air adapter to air feed tube.
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Drozd and Blackbird Discussion / Re: Volumetric efficiency mod.
« Last post by East Milford on May 09, 2017, 04:13:14 PM »Pics
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Drozd and Blackbird Discussion / Volumetric efficiency mod.
« Last post by East Milford on May 09, 2017, 04:07:49 PM »It took a while to figure out a way to get velocity readings under full-auto fire but, i did, and the data was not surprising, as I suspected. It seemed clear to me that in single shot the FPS is significantly faster than what comes out under full-auto strings at 4k-6k. So after confirming this, a drop off from 1100 fps to around 700-800 fps during long automatic strings, I started to investigate.
The major restriction lies in the air source inlet. The steel adapter that feeds the intake manifold tube.
The air port that transfers the air from your hpa source into the air tube is literally a pin hole!
Now this isn't necessarily a problem for single shot or sliwer cyclic rates but once the RPM of fire starts quadrupling the factory deaign, the Drozd suffers considerable starvation of air during Full-auto.
If you do this mod the gains will be a night and day difference at full auto. You will pick up several hundred FPS at 4k-6k speeds. You will even gain a couple hundred FPS at 2k rpm cyclic rates.
The Mod is self explanatory and essentially free. What needs to be done is a Porting of the air intake adapter. Think of it like porting a throttle body or intake manifold on a car. The same reasoning applies
To increase the volumetric efficiency you will want to allign the intake tube inlet hole with the pin size air adapter outlet hole. here are some pictures of how i did this.
I used a 5mm drill bit to enlarge the outlet hole and create a straight through port into the manifold tube.
Next i Tig welded the two pieces together to permanently seal the connection.
Its basically a free mod with huge gains for those running 2k-6k boards.
Hope this may help someone
The major restriction lies in the air source inlet. The steel adapter that feeds the intake manifold tube.
The air port that transfers the air from your hpa source into the air tube is literally a pin hole!
Now this isn't necessarily a problem for single shot or sliwer cyclic rates but once the RPM of fire starts quadrupling the factory deaign, the Drozd suffers considerable starvation of air during Full-auto.
If you do this mod the gains will be a night and day difference at full auto. You will pick up several hundred FPS at 4k-6k speeds. You will even gain a couple hundred FPS at 2k rpm cyclic rates.
The Mod is self explanatory and essentially free. What needs to be done is a Porting of the air intake adapter. Think of it like porting a throttle body or intake manifold on a car. The same reasoning applies
To increase the volumetric efficiency you will want to allign the intake tube inlet hole with the pin size air adapter outlet hole. here are some pictures of how i did this.
I used a 5mm drill bit to enlarge the outlet hole and create a straight through port into the manifold tube.
Next i Tig welded the two pieces together to permanently seal the connection.
Its basically a free mod with huge gains for those running 2k-6k boards.
Hope this may help someone
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