Air Machinegun Forum
General Air Machinegun Discussion Category => Drozd and Blackbird Discussion => Topic started by: Parellax on January 26, 2016, 12:52:30 AM
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It looks like Hodaka has beat me to a functioning prototype. That suits me just fine because everything he turns out is grade "A"+++. I can't wait to try this puppy out! I will be waiting by the mailbox. You'er freaking awesome by the way Big H!
(http://i284.photobucket.com/albums/ll27/masondawson2/roller1_zpsbwagb3qo.jpg~original) (http://s284.photobucket.com/user/masondawson2/media/roller1_zpsbwagb3qo.jpg.html)
(http://i284.photobucket.com/albums/ll27/masondawson2/roller2_zpsc0ehn1ch.jpg~original) (http://s284.photobucket.com/user/masondawson2/media/roller2_zpsc0ehn1ch.jpg.html)
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Thanks for the kind words! I hope it functions as we hope! If it can keep the BB's from bouncing back out at high rpm's and not bind things up, we should be able to reliably increase the feed rate!
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I received the prototype auger shaft today. Why is it that whenever there is something you really want to do people start coming out of the woodwork for you to do things you would rather not? I barely had time to squeeze this test in after I tried some long 2K bursts of about 250. BTW. There is no shot limit of 256 on the SB-4K. I burned up two aftermarket seals doing that. I need a source for some better ones. There were very few air shots in those long runs with no spans that lasted for what I could tell more than two in a row. It was pretty damn magical.
This is how the magnetic auger shaft (MAS) performs with only 50 bb's in the hopper. I may not have had a single air shot because after I filled the feed channel, and dumped the rest of the bb's out of the hopper there were several bb's stuck to the auger before I put 50 in. There is some lag in the video that I hope to get rid of after I update it.
https://youtu.be/XHZZ-QXiX-I (https://youtu.be/XHZZ-QXiX-I)
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Interesting. More testing to be done, eh? Looks promising.
I was wondering if there would be any issues feeding bb's once the mag's reservoir is full due to the bb's becoming stuck together from the magnet.
You mentioned that you "burned up" two seals. Are you talking about the breech seal?
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I just did this test to see how it would work under the worst conditions. It works fine with a full mag. The field doesn't go much further than two, or three bb's. We would like to send the barrel testers one to keep. Yes. More delays, but we have our fingers crossed for spring. That would be better anyway.
I burned up the front valve seal twice. They are PU. I dug around to find one of the stock seals, and didn't have anymore problems. That's the first time that happened with the PU seals. Of course I was punishing them severely.
I did more testing today to see if the auger would help past 2K. Nope. The 14280 just isn't fast enough for what I want to do, but I think I found my solution. The dimension's are almost exactly the same so it should drop in. The only problem is I will have to wait until April for them to ship:^(
http://www.jameco.com/1/1/28172-ms5n-1885-r-12-volt-dc-motor-9820-rpm-nominal-voltage-12vdc.html (http://www.jameco.com/1/1/28172-ms5n-1885-r-12-volt-dc-motor-9820-rpm-nominal-voltage-12vdc.html)
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The motor specs look just like the MD5 - one of the original replacements for the BB motor. I have some somewhere, but I don't think they are the higher speed versions. If I find one like you want I will send it to you.
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That would be awesome if you had one! No matter if you don't. One of us will be sending you a MAS from the first production run. BTW. I purchased this unit in 2014 to learn how to solder. It is totally badass for the price.
http://www.ebay.com/itm/Aoyue-968A-4-in-1-Digital-Hot-Air-Rework-and-Soldering-Station-/110839316933?hash=item19ce89c1c5 (http://www.ebay.com/itm/Aoyue-968A-4-in-1-Digital-Hot-Air-Rework-and-Soldering-Station-/110839316933?hash=item19ce89c1c5)
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That is a really nice solder/hot air set up! I am going to get one. Thanks for the link Parellax.
That's great that the MAS is working. I was thinking about the magnetism and how strong the magnets really need to be.
I don't know, you will have to tell me, but I was thinking that you could use magnets interspaced with non-magnetic material inside that brass tube if need be. Basically, alternating magnets and non magnetic material, rather that filling the tube all the way.
Also I was thinking you don't have to magnetize the output end of the MAS. Don't know. I'd have to test it and see.
Anyway Hodoka and Parellax, great work so far! Keep it up. I love to see the creativity!
---Cam
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Only this one, the lowest speed one..
In their catalog it is listed as a 4000 rpm motor.
From Jameco:
232013 ReliaPro MD5-12160R 15 12 12-24 0.30 4000 34.3 39.1 0.12"/solder 0.091 0.622 1.082 x 1.279
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I don't know what strength magnets Hodaka used, but when I made one I used an N42 bar magnet. It didn't jam it up. I epoxied it into an antenna section. Where I went wrong was trying to use disk magnets for the ends. Because of the block magnets' polarity it made it impossible for the end magnets to stay flat. One of us will send you one to play around with. It's a good idea to grease the chamber the spring rides in because the magnet pulls on the spring making it rub the inside. This is the magnet I tried.
http://www.kjmagnetics.com/proddetail.asp?prod=BC22 (http://www.kjmagnetics.com/proddetail.asp?prod=BC22)
I appreciate you looking TBK.
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Ok. Yeah send it out to me. I'll try it out. Thanks
That is a good site you found for the magnets. Seems they have a better selection of small size rod and disc sizes.
If I choose a magnet to try, I would use these inside the auger shaft:
http://www.kjmagnetics.com/proddetail.asp?prod=D14 (http://www.kjmagnetics.com/proddetail.asp?prod=D14)
Or these:
http://www.kjmagnetics.com/proddetail.asp?prod=DH14 (http://www.kjmagnetics.com/proddetail.asp?prod=DH14)
http://www.kjmagnetics.com/proddetail.asp?prod=D24 (http://www.kjmagnetics.com/proddetail.asp?prod=D24)
If the spring rubs because of the magnetism, would it be better to have a less powerful magnet?
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The reason I chose the ones I tried was because Hodaka found that trying magnets that are polarized like the ones you are considering barely have any pull on the sides. The bb's just snap to the ends.
I was playing around with it today, and found you don't even the agitator with the MAS making it much quieter.
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I have 5 more cut, stuffed and glued, just need to put them on the lathe and cut them down, should have them shipped to Parellax by mid week! Nice we don't need the agitator with these, that thing is annoying!! Will make a much quieter experience, easier to sneak up on those waskly wabbits!
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Yes. It actually sounds pretty cool. All you need to do is plug the hole where the agitator pivots.
To my surprise the two motors I ordered came today. It was an easy swap. All I had to do was slightly widen the hole the shoulder of the motor goes into. That's what made me try it without the agitator. It's quite an unpleasant sound at 10K RPM. I almost tore it back down before I tried shooting it after turning it on.
So far it only works a little better above 2K. It's a lot easier to hear what's going on without the agitator though. If I have time tomorrow I will put a stiffer spring on the clutch, and see how that works.
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So I'm curious as to how reliable 2k is now?? Have we at least made it that far in reliable feed speed?? If so, I will order a few of those motors!
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I did a single test without the agitator into a bucket of water with the new motor. In one pull of the trigger the counter ended at 76. There were 78 bb's in the bucket.
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BTW. This trap is a full length piece of 3/4" EMT conduit directed into a 5 gallon bucket that is stuck in another bucket. The water level is four, or five inches from the top. The bb's are starting to make the first bucket leak into the other one at 1K psi.
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The reason I chose the ones I tried was because Hodaka found that trying magnets that are polarized like the ones you are considering barely have any pull on the sides. The bb's just snap to the ends.
Yes, but if you separate axially magnetized magnets by something non-magnetic, like plastic, you will get stronger attraction between the magnets. Here, let me illustrate this idea. In this photo in the bottom right are 1/8" x 1/4" rod magnets sticking together. The bottom left are the same magnets separated by about 1/8". At the top of the photo is a plastic tube with separated magnets inside. See what happens?
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Like I said before, I don't know exactly how strong the pull force needs to be, but if Hodoka's shaft has too much pull, this is the way I would fix that issue. Anyway, it might be fine just the way it is.
BTW, these are the smallest diameter rod magnets with diametric magnetism. (1/8" x 1/4") If you want to experiment.
http://www.kjmagnetics.com/proddetail.asp?prod=D24DIA (http://www.kjmagnetics.com/proddetail.asp?prod=D24DIA)
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I was thinking about using three instead of four magnets and leaving the very end non-magnetized. That would keep the spring from being pulled so much and rubbing and lord knows, I don't want my "shaft" to have too much pull!?! I think I will rip apart the ones I have waiting for the lathe and re-do them!
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Very interesting Cam. I just did some more testing with a stiffer spring on the clutch. I got 3K 100% at ten round bursts. I also got 38 bb's with 38 on the counter at 3K. There is something not quite right with the firmware at 4K I will have to go over with Sergey though so I can't cet an accurate count. I tried to use the prototype 4K board, and burnt a mosfet so it will be a while before I can say definitively if it is shooting 4K 100%. All I can say is that it feels like it is. I will try to make a video today.
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Here is the video...
https://www.youtube.com/watch?v=d-B0_E75JpA (https://www.youtube.com/watch?v=d-B0_E75JpA)
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I was thinking about using three instead of four magnets and leaving the very end non-magnetized. That would keep the spring from being pulled so much and rubbing and lord knows, I don't want my "shaft" to have too much pull!?! I think I will rip apart the ones I have waiting for the lathe and re-do them!
Good thinking. The output end does not need to be magnetized.
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Here is the video...
https://www.youtube.com/watch?v=d-B0_E75JpA (https://www.youtube.com/watch?v=d-B0_E75JpA)
I like your bb trap. You just need to extend the pipe into the bucket and/or seal up the hole in the lid around the pipe, eh?
Ok, now things are looking quite promising, but there is a but. You need to test with longer bursts than 20-30 or so shots. The neck of the magazine contains about that many bb's. The action of the air flowing from the valve into the barrel creates a vacuum that will suck the bb's from the neck of the magazine. Kind of like how a strafer bb machinegun pulls bb's from it's "magazine". You may see this if you turn off the motor and fire the gun with just the neck full of bb's.
I would suggest doing 100-150 round tests.
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I was just thinking, as an addendum, the vacuum effect may not be as bad if you have done the magnet mod in the neck of the magazine...
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On this mag I am using a 30 rnd valve body with no magnets at all. The end of the barrel doesn't seem to be taking any damage. After I receive another MAS I will test it with longer bursts. I broke the prototype doing another test later that day. The next ones should be Parellax proof. I don't really think the vacuum effect would go past the vent ports.
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Yea, my bad, I knew solder wouldn't hold long but figured I would get you one fast for testing. The rest will be pressed, epoxied and turned! Parellax proof for sure!
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Great news you are making progress! Keep at it.
Parellax, what issue did you find with the 4K speed? Is it not doing 4k? What happens between 3K and 4K? All work but 4k?
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I think there is a glitch in the code. When I switch from 3K 10 rnd burst to 4K full the counter runs at 4K full, but the gun only delivers a 10 rnd burst at 3K. When Sergey get's back to Russia he is going to take a look to see what might be going on. I haven't tested the between settings. Just before I went to Canada I broke the MAS. Hodaka was aware of the potential problem, and has corrected it. I fixed it this morning for some more tests, and discovered why bb's were going everywhere.
(http://i284.photobucket.com/albums/ll27/masondawson2/20160208_101749_zpsdbmcegsz.jpg~original) (http://s284.photobucket.com/user/masondawson2/media/20160208_101749_zpsdbmcegsz.jpg.html)
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I did some more testing today with the Nichibo, and the SB-4K. I was able to get it to reliably fire 3K. Everything I did to get it to 4K did not work. Half were air shots at best. I am still not ruling out the Nichibo because I still have some clutch adjustment left, and I haven't brought the motor to the point of stalling. I was able to fire three 10 rnd bursts at 4K with the new motor with reasonable success. The first shot 11, and the second two shot 9. I think I will have it tomorrow.
TBK. There is nothing wrong with the firmware on the SB-4K. I discovered that in all of the testing I have been doing my valves have been taking a beating with all of the air shots. The valve was just hanging up after a consistent amount of shots had been fired at 4K. I figured it out when a valve became stuck open. A little time with the Dremel, and viola! 4K works fine now.
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I'm starting to feel like 4K is like trying to break the SB with a BB. I believe the main problem is when you get the torque needed the auger spring compresses bypassing the clutch, and does not allow bb's into the auger. Aaarg! Going to set it aside for a few days.
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Well, don't give up. We've all been there before!
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I can't give up now. I have way too much wasted time invested in this endeavor :) I'm pretty sure I have a simple solution. Hopefully the next video will be 100% instead of 82%. Thanks for the encouragement!
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Fresh off the lathe courtesy of Hodaka Interprises here is the first production run of magnetic auger shafts available for the Blackbird.
https://www.youtube.com/watch?v=yNsIZs-rzAM (https://www.youtube.com/watch?v=yNsIZs-rzAM)
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I think i hit the head on the nail with this one. It's an audio of what it sounds like to me when a few people from all around the world try to make something happen, and succeed.
Success can't be measured in volume... Only in goals.
https://www.youtube.com/watch?v=50moUbwgoAQ (https://www.youtube.com/watch?v=50moUbwgoAQ)
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Couldn't agree more! Takes a ton of time, dedication and pushing through failure, but an awesome end result is more than worth the frustrating times and keeps the fun in what we do!
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Yeah, but where are all the swearing noises.....Heh!
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We had to edit it to a "G" rating,, for those with virgin ears!?!
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Yes. They are "beeped" out.
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...thought so! ;D
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This is a demonstration of a magnetic auger shaft working in an otherwise totally stock mag using stock voltage. The bb slider,and it's return spring have also been removed. If I sound annoyed in the video don't let that fool you. I was actually very annoyed.
https://www.youtube.com/watch?v=gkSffgr-Nkg (https://www.youtube.com/watch?v=gkSffgr-Nkg)
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In testing TBK's auger with the 10K motor with 24V I have found it spins too fast for the bb's to enter the auger. It works excellent to at least 3K with magnets in it using the 4K motor, and 18.5V. That is way better than it was designed to handle. Thinking of how the bb's were sliding right over the auger brought me back to the design Hodaka, and I came up with. I used a heavier auger spring in the video shooting 4K at 92%. That seemed to help a lot. I was looking at that assembly today, and a light bulb turned on. I noticed one side of the spring was almost touching the shaft. I tried the best I could when I was fabricating it to keep the shaft in the center of the spring, and was already aware of this imperfection. It was then I had the idea to make another spring with a closer ID to the shaft OD. What I ended up with is a snug fit with the spring touching the outside of the shaft pretty much all around. I haven't shot it yet, but I did test to see how it feeds. Here it is dumping a full mag at a rate of 83 bb's per second. I am also not using the slider in this test. The bb's look like angry bees swarming out of a hive.
[urlhttps://youtu.be/TYw1-JgELac][/url]
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I tried the best I could when I was fabricating it to keep the shaft in the center of the spring, and was already aware of this imperfection. It was then I had the idea to make another spring with a closer ID to the shaft OD. What I ended up with is a snug fit with the spring touching the outside of the shaft pretty much all around.
It sounds like you turned it into an auger!! It looks like it is feeding great! Good comparison of bees swarming out of a hive! Glad you separated out the feed of the magazine from your firing test method. That way you can see what isn't allowing it to actually fire at the rate you want. As expected, it probably isn't that the feed isn't good, but a combination of things that aren't allowing you to hit your target firing rate. It shows a good BB flow from the mag, so that can be crossed off the list.
What rpm are you getting on your spring to feed the bbs at that rate? The auger isn't really spinning too fast... it is spinning however fast you are driving it. I have augers in every configuration you could imagine, and quite sure it will feed the BBs at whatever rate you want. It just has to match the rest of the system. The TBK auger you have feeds flawlessly at the normal ROF and voltage in the Drozd guns. Good job of showing how much beyond that it can easily go!
Keep up the good work!
TBK
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I shot it after I posted. It seems to be in sync with the clutch. I shredded a cardboard box with about four hundred rounds. I only used a full 13ci bottle at 1200psi so that dropped it down to 500psi. I'm really pleased with bringing the coils closer to the shaft. It has the potential to bring the bb's closer together on the auger.
It's very difficult to get a reliable RPM measurement because of the pulsing nature of the system. Every time the solenoid is actuated it draws current from the motor. The lower the rof the more apparent this becomes. If I were to guess I would say an average of somewhere around 8000.
I'm thinking a magnetic auger with peaks, and valleys might work well also for extreme rof.
I haven't forgotten about testing your auger using lead. Any ideas on how to capture the shot so it's easy to count?
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Holy cow! 8000 rpm on the spring, or is that the motor?
My suggestion was just like you did with the BBs in the tub out of the bottom of the mag, or out the top of the mag with the valve body off. Just an idea of the pickup in the auger for the first scenario, and then around the 90 degree angle and up the mag neck to make sure the larger diameter and softer lead can make the bend.
Not sure what you mean by peaks and valleys.
TBK.
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8000 estimated at the motor.
Thanks for the tips on using lead.
Instead of a solid pushing force what I found is that it works well to magnetically guide the bb's into the feed channel. Peaks, and valleys could achieve the same thing with plastic that I have done with metal. Picture a low profile prism wrapped around the shaft instead of a wire. I don't think it will jam when the bb's enter the channel because everything is rolling. Also the surface area for bb's could be maximized. In addition if it works it would take up less space on the bottom side of the auger.
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Another test in my back yard at 4K further confirms I am in a happy place. One of the good things about 4K for me is even though it's loud it is so fast that it sounds more like a high voltage arc. I'm pretty sure my neighbors would love to see my house burn down, or me electrocuted so there is no concern of theirs to call any authority. I love it when a plan comes together.
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Very cool Parellax!
It would be interesting to see the "bee's" flying out of the neck of your mag with the mag head off!
I have had one of TBK's augers installed for quite a while and ready to shoot. Just have been so busy. I have also been building a deck at my shooting range that will really make for a great platform to shoot from when completed.
Hope to play soon enough too!
Keep up the great work.
---Cam
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Thanks. Great suggestion. I'll do it. I wonder how far it will spit them. The motor force alone will mushroom the mag firing at speeds under 4K without using a retainer clip. I found some small zip ties that should hold it together in the B.
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Here you go Cam. It seems that it pretty consistently has a hiccup about one fifth into a full mag so that's why it is not loaded to the top. I'm fairly certain it would not happen if I was using the slider. It's just so loud at the rate it's spinning even with one lobe shaved off. I might try bending the strike plate on the slider for less contact, but I would rather keep on not use it at all.
BTW. To anyone who is running the SB-4K. If you do this test it will cause your solenoid to heat up in the higher Rates of fire without a mag in the gun because it can't cycle without something like the valve pushing it back. It would be a good idea to do this with a mag in the gun weather it's another BB, or 30 rndr.
https://youtu.be/zeZuWJbhQZk (https://youtu.be/zeZuWJbhQZk)
Here is the auger with the heavier gauge spring with a smaller ID.
(http://i284.photobucket.com/albums/ll27/masondawson2/20160526_120312_zpseb8lbieq.jpg~original) (http://s284.photobucket.com/user/masondawson2/media/20160526_120312_zpseb8lbieq.jpg.html)
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Wow! That was cool to see the "bee's" swarming!!!
Seems to work pretty well enough!
I filed down the cam lobes for my shaker on one of my mags years ago to help reduce the air shot problem. It worked pretty well.
I filed them down so they just barely made contact with the shaker.
Give it a try.