Pneumatic Bottle Capper - Just...because.

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More delays. Who knew dropping a magnet demagnetizes it? New magnet for the bell is ordered. Almost ready to roll.
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With an Edison bulb or two, several brass gauges, a little more brass plumbing, and some leather wrapped handles you'd have a glorious steam-punk contraption.
 
Haha, you're right.

This new $1.85 magnet will arrive Wednesday.



By Thursday my life will return to normal. It WILL work.
 
With an Edison bulb or two, several brass gauges, a little more brass plumbing, and some leather wrapped handles you'd have a glorious steam-punk contraption.
Well, I didn't want to wrap leather around my stainless handle, Edison bulbs are banned in California due to Title 24, and all my gauges are built into my kegerator. BUT...



Video soon... Making minor adjustments to the end of the carriage...
 
New problem, and it's a big one. To this point all my testing has been done at 20 psi, just to fine tune the bell picking the cap up consistent and square. Last night, after being satisfied I'd accomplished that, I poured the coals to her. Mangled cap, everytime.

I thought perhaps my spring pressure on the retractable bell mag was too strong, so I lowered it to the point of removing the spring entirely and letting the assembly free float with the same result. Pulling the mag cylinder out of the bell results in consistent crimps within specs at 120 psi as predicted by the math.

All this leads me to the conclusion that even a miniscule alignment error is fatal. It appears as if the magnet's hold on the cap is so strong the bell is unable to naturally center the cap on the bottle.

At this point it seems the only solution is to force the bell magnet to mechanically retract as the crown contacts the bottle. Doable, but we're talking about a basically useless endeavor to begin with.

I've invested quite a bit of what limited time and brain power I have in this project already, and am fighting an internal battle whether to tap out or fight to the death for a contraption that has no real purpose other than to prove a point.

Ugh.
 
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The problem isn't the bell, and it isn't that the magnet won't retract. It's that it's death grip, which is required to suck the crown up off the carriage, is so great that it doesn't allow the crown to self-center on the bottle.

So I have 3 options as I see it.
1. Give up.
2. Fab a retractable electromagnet that de-energizes as it touches the bottle.
3. Fab a retractable magnet that's downward travel with the bell is limited by an external stop.

#1 would scar me. #2 introduces a layer of complexity even I'm shying away from. #3 isn't out of the question.

The ram connects to the bell via a 7/8" rod coupling. A cylinder magnet inside the bell COULD be fabbed to hang freely until, via a slot in the rod coupling, it nears bottle contact at which point it's pulled away. I think it would solve the problem. The operative word in that sentence is 'think'.

It's a wonder my wife still loves me.
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So a 1/2" diameter aluminum rod about 2" long with a 1/4" cylinder magnet pressed in the bottom, could be drilled and tapped horizontally to accept a 12-24 threaded 3/16" stainless rod screwed in through a slot in the rod coupling, which would hit a stop on the capper frame, thereby releasing the crown just before it hits the bottle. The pneumatic cylinder ram would have to be counter bored at 0.510 to provide centering stability for the top of the aluminum rod, with the bell centering the bottom half.

It all sounds so easy. LMAO. Meanwhile, I haven't brewed in 2 months.
 
Even better, make the magnet rod stainless to give it more mass. The slot in the rod coupling would capture the 3/16 rod to limit it's down travel to the point it just contacts the centered crown. With more mass, gravity would ensure the mag is always in position unless mechanically stopped out...

All suggestions welcome here. Back burner issue pending a sane decision. I'm out...

PS. Forgive my mental masturbation as I weigh failure vs. more wasted resources...
 
OK, I'm about done. After I thought about it, the magnetic bell is really something I want irrespective of the mostly useless auto cap feeder. Without the feeder I think I could just switch to a less powerful magnet, but frankly I think I'll get better alignment with this new method. I can adjust the elevation at which the bell drops the cap, and I'm guessing an instant before it hits the bottle will be perfect. The new bell is JB Welded to the rod coupling and drying now, and the new magnet is JB Welded in the new retractable bell mag cylinder and is drying. The rod coupling is sleeved, and slotted where the rod that moves the mag cylinder sticks out. The ONLY thing left after this Wonder Weld dries is fabricating a stop on the frame to pull the magnet up.

new bell mag.jpg
slotted and sleeved bell assy.jpg


Edit: Haha... Supreme welding skills on display. That heim joint bracket has been tacked on and moved, welded on and moved, cut, hacked, and moved again. It's pretty much hidden when it's assembled, so no, I'm not fixing it. lol
 
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If there's still any interest in the working video let me know, and I'll make one after I assemble it.

But... cutting through the fog of this auto-cap feeder, the main take-away from my mind numbing 'contributions' to this thread is, a 2" diameter pneumatic cylinder will NOT work to crimp crown caps on. The 2-1/2" cylinder STILL requires 120 PSI to get a crimp in specs with one press.

Given the small price difference, I wouldn't even consider using anything but a 3" diameter cylinder if I were starting from scratch.

By the way, my daughter is a BJCP judge. I asked her if any part of the judging looks at cap crimps, and she told me no. She wasn't aware there were specifications. She got a Crown Go-No-Go gauge in her Christmas stocking. So fair warning, if she's a steward on a comp you're entered in and your crown is out of spec, you're gonna know. ;)
 
Just when I thought my problems were over. It appears the bell magnet couples with the rod nut through the stainless shaft, something I'm surprised to see. So not only do I need a down travel limit, but I need a limit to force it back down at the top of travel. It also takes an enormous amount of force to decouple it from the cap in the bell, which created the problem in the first place.
All this means is I need to fab a new rod, and put it in an external groove that limits it's travel. Another night in the shop...
 
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Well, I didn't want to wrap leather around my stainless handle, Edison bulbs are banned in California due to Title 24, and all my gauges are built into my kegerator. BUT...

There are no words for this level of awesome!

Just when I thought my problems were over.

I can't believe how much I missed in this thread after taking a couple days off. I find myself completely unable to look away, every post is like the end of episode cliffhanger that keeps you up till 4am watching "just one more".
 
OK, I'm gaining ground again. To re-cap (Pardon the pun :p), everything was fine until I tried to crimp a crown on the bottle. It seems the magnet I have to use to suck the caps into the bell was so strong it took away the bell's natural ability to center the cap on the bottle. A billion of an inch off resulted in a mangled cap.

So I made a new bell magnet, manually retractable, and fabbed a sliding stop so the magnet is down when it picks up a cap, then lifts up and drops the cap on the top of the bottle.

Theoretically, of course. Hugely theoretically.

This design fix was a tough one for me, I'm an electrician not a machinist. It damn well better work!

I'll probably do something different with the Rube Goldberg spring, I may not even need that outward pressure on the cylinder. I'm thinking since the mag cylinder is cantelevered off the control bolt, it may need that spring to keep her centered. We'll see...

I may not have time to bolt it on and try it out for a day or two, but I'm chomping at the bit. This COULD be it...
bell mag.jpg
sliding stop.jpg
 
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I'm staring at it thinking, yea, that spring has to go. I think the sleeve I put in the rod coupling is tight enough to overcome the counterweight, which won't be horrible anyway 'cause my stop is 1/8" from the side of the rod coupling, just what it needs to clear the lip of the bell.

And I see I have some vise marks to polish off that 1/2" stainless rod. Amazing how much better I can see this stuff in a picture. It wasn't like this when I was your age, lol.
 
I hurriedly bolted the stop to the frame. Anxious to check operation... Lots of critical measurements here.

Looks like she's gonna work!

 
every post is like the end of episode cliffhanger that keeps you up till 4am watching "just one more".

Haha, from my perspective it was approaching nightmare status as what seemed like a relatively simple design build was evolving into ''The impossible." But I'd shot my mouth off, so...
 
I'm not even going to assemble and test. Pretty confident at this point. I'm going to tear everything down, and clean up my re-model boogers as best as I can, clean, final assembly, and video.

This may end up being the only 8 cap auto-feeder that will ever exist. I promise to share a video.

This has been a very rewarding and educational project. ANYTHING is possible if one focuses on solutions rather than problems. My favorite all-time quote is credited to the great Henry Ford:

“Whether you think you can, or you think you can't--you're right.”

Truer words have never been spoken. My best to all...

Skål !!
 
So... If a pneumatic capper is already gross overkill, would a 6-cap auto feeding cap cartridge be heresy? 'Cause I just came up with design that would cost about $8.00 and be simple to implement...



{Edit: It just became a rhetorical question. Already bought what I need on eBay for $8.50. It'll be an 8 cap autofeeder, and take about 3 hours to fab and install ;) }

When 3 hours turns into 43 days...
 
SD, I have been following this thread with awe and amazement! This is one of The coolest things I have ever seen created and I applaud your tenacity to get it right and finished. I can't wait to see the video!
 
Wow, well I promise not to disappoint! Status right now is the bell magnet stop rod needs some adjustment. 100% certain I'll get it dialed in. With respect to cap pick-ups, I think I sent about 300 caps down the chute tonight, and after a billion fine adjustments it's perfect. :rock: Rock solid. For a while it felt like I was adjusting a QuadraJet on an old Chevy with a vacuum leak. I'll address the stop rod this weekend. VERY CLOSE...
 
Great news! Just when it started getting boring over here another design flaw cropped up. :smh:

Everything is roses until a cap is crimped on a bottle and the capper head is on it's way back up. The carriage follows the bell up to provide a new cap, but while doing so the hinged magnet on the end of the carriage sticks to the cap it left behind on the bottle, prematurely pulling it away from the carriage. I NEED that magnet in place until the last instant to center the cap under the bell before releasing it.

It appears the best fix is to add more weight to the carriage magnet arm counter-weight, quite a bit actually. So I'm going to have to tear it down, bore a 5/8" hole in the back of the carriage magnet arm, and press in about a 6" piece of stainless bar stock. A perfect way to break up what I thought was going to be a smooth ride to the finish.

But besides that... :ban:
 
Better idea... The counter-weighted bar that holds the carriage magnet hinges. It has to, as it's forced down as it nears the bell, releasing it's grip on the cap at the end of the carriage to let the bell magnet take over. Despite my best efforts, the hinge point has more play than I'd like. This is kind of a big deal, because the magnet has to stay centered on the carriage, and it's a little over 3" from the hinge point. So 0.030" play in the hinge = over a tenth at the end of the carriage. Barely acceptable. One of the most difficult challenges has been getting the cap square in the bell. A little off center and the bell magnet wants to grab the edge of the cap where there's more mass.

So... a cap that's 0.050" left or right of center of the bell hasn't been optimum. If I add more weight to the counter-weight to keep the carriage magnet in place as it passes the fresh bottle cap, I'm afraid the magnet arm will gain vertical stability but lose lateral stability with the extra wieght, exacerbating an already marginal condition.

I think a better solution is... wait for it...

More magnets. A magnet countersunk at the back of the counter-weight will grab a magnet embedded in an aluminum bracket bolted to the bottom of the carriage. Placed properly, this will not only provide the down force needed to keep the carriage magnet in place as it passes the capped bottle, but also GREATLY improve lateral stability, as it will be several inches from the hinge having plenty of leverage to keep things in line. I did some tests, and these new magnets will far enough away from the caps in the carriage to have no effect on their movement.

A little more work than adding more counter-weight... but I'm not about to let cumulative errors kill me at this point.

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The foot pedal valve supplies compressed air to the cylinder only while the foot pedal is pressed down.

Thanks, everybody, for the awesome thread! I've just discovered it and I'd love to attempt to build one.

A question about the foot pedal. Is there a way to make it work in such a way that after pressing it briefly (activating it), the air cylinder performs the whole stroke and returns back? Is there a special kind of solenoid valve needed or a simple controller attached to the solenoid? I think it would make it a little faster to use if you didn't have to keep it pressed (even though it's just a second or so).
 
Thanks, everybody, for the awesome thread! I've just discovered it and I'd love to attempt to build one.

A question about the foot pedal. Is there a way to make it work in such a way that after pressing it briefly (activating it), the air cylinder performs the whole stroke and returns back? Is there a special kind of solenoid valve needed or a simple controller attached to the solenoid? I think it would make it a little faster to use if you didn't have to keep it pressed (even though it's just a second or so).



Have a read here under "choosing and air directional............"


https://www.mcmaster.com/pneumatic-foot-switch-pedals
 
Have a read here under "choosing and air directional............"


https://www.mcmaster.com/pneumatic-foot-switch-pedals

Thanks, Stealthcruiser! Unless I'm not reading it correctly, in all of the cases it says that the air cylinder retracts as soon as you release the actuator (the pedal in this case). What I was asking was the situation that the cylinder doesn't retract after your release the pedal but rather run a full circle (caps the bottle) and then is retracted by the spring. What am I missing? (Thanks for your patience, I'm really new to this.)
 
What I was asking was the situation that the cylinder doesn't retract after your release the pedal but rather run a full circle (caps the bottle) and then is retracted by the spring. What am I missing? (Thanks for your patience, I'm really new to this.)
Use an off the delay DC or AC solid state timer depending on your pneumatic valve. As soon you release the start cycle button the off delay timer will keep the voltage on for a preset time and retracts the cylinder after the time has elapsed.

Click to see a Solid state DC off delay timer sample
 
Thanks, everybody, for the awesome thread! I've just discovered it and I'd love to attempt to build one.

A question about the foot pedal. Is there a way to make it work in such a way that after pressing it briefly (activating it), the air cylinder performs the whole stroke and returns back? Is there a special kind of solenoid valve needed or a simple controller attached to the solenoid? I think it would make it a little faster to use if you didn't have to keep it pressed (even though it's just a second or so).

There has been many threads on this type of capper. Here is a thread that I thought was interesting My dad IS the $h|T. I was seriously wanting to learn about it until another very wise member pointed out the dangers with it since it lacked a few safety features.

These units have the necessary safety mechanisms that you may want to try and duplicate.....

https://www.morebeer.com/products/ferrari-pneumatic-bottle-capper.html
https://www.morebeer.com/products/ferrari-electric-bottle-capper.html
Accidents happen. If only I had listened to the HBT member's warning....... ;)

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Thank you, CodeSection for the warning! You're right—you can't be too safe with glass and pneumatics. I'm definitely thinking of testing what the minimum capping force would be and also utilizing the flow restrictors on the way down.
 
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