Pneumatic Bottle Capper - Just...because.

[BeardedBrews]

You may have the most luck fabricating the cartridge with a lip instead of a magnet so that the caps are not held onto the cartridge in opposition to the bell magnet:

You could also consider shortening the cartridge and using it to index a single cap out of a vertical stack of stationary caps. Each down cycle of the bell would then release one cap into the cartridge to be positioned on the up cycle. Stacking the caps vertically will make it much easier to pre-load an entire bottling session of caps, and they'd be positioned correctly to stay fairly sanitary during the process.

 

[SDBob]

You may have the most luck fabricating the cartridge ...

That's great input. You may be right about the lip. My bell magnet is an N42 1/4" dia x 1/2 long cylinder, which should, given the fact that it'll have substantially more surface area contact, easily overpower the cartridge mag. Frankly I avoided the lip for clearance issues, but I think now after seeing linkage in my sleep for two days, I can work around those. I'm certainly going to experiment before I remove too much material.
With respect to your vertical loader idea... Haha, I like the way you think. Not sure my wifey does though! Honestly I keg my beer, I only need bottles for competitions and road trips, so I'm resisting the urge to take that challenge...

 

[SDBob]

I ended up with an extra pneumatic cylinder, 2-1/2" bore, 2" stroke, selling for $35 + shipping on eBay if anyone is interested in building there own!
https://www.ebay.com/itm/263421391519?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1558.l2649

 

[SDBob]

You were right about the magnets interfering. The bell picks it up ok, but it kinds of drags of the other. No worries. And I've drawn my linkage for the 4th and final time! It's going to be so critical how that cartridge not only escapes the bell, but reapproaches it too. Down and out quick.

 

[SDBob]

Started the linkage today.

 

[SDBob]

Haha... There's a chance this thing is gonna work.

 

[-TH-]

Waiting for the 2-1/2" cylinder; decided to address the magnetic crown holder. After messing around will all kinds of magnets in the bell, realized the only solution is a magnet that captures the crown to center it in the bell and spring loads into the bell. I saw this design in a hand crimper, wanted to avoid it because of it's complexity fabbing a one-off, but what the hell... should work swimmingly. Ordered a 1/4" dia x 1/2" long cylinder magnet from KJ Magnetics, some JB Weld should hold it in place...View attachment 551847 View attachment 551848

FYI I made a capper recently with a magnetic cap holder, but the way I did it was to bore a hole in the end of the cylinder rod in a lathe. This allowed me to use a spring loaded plunger that I made out of plastic. The plunger is cylindrical but has a shoulder on it so that the wider end is retained by the capper bell. In the center of the narrow end I pressed in a strong magnet.

Sorry I don't have pics, I don't have that capper anymore.

 

[SDBob]

FYI I made a capper recently with a magnetic cap holder....

Pretty much the same route I went. It's still going to be dicey getting that Bell to come down on that cap so it centers right everytime. Early experiments are promising, but all the stars have to align.

 

[SDBob]

Slow but steady progress...

 

[SDBob]

Machined out the cap chute, looking more and more plausible...

 

[SDBob]

The caps slide down too fast, sometimes making them fall off, sometimes wanting to stack. So I HAVE to secure that lead cap with a magnet under the cartridge. If it's sucked down, all caps slide down perfect, every time. But my experiments have shown that I can't have other magnets near the bell because they interfere with the bell magnet causing the cap to be dragged off all sorts of sideways. I lost sleep over this conundrum last night, as this adventure is well past the point of no return. Had to run to the shop this morning before work and rough draw this idea. This will place a magnet under the cartridge when I need it, and pull it away when I don't. As always, happy to be of entertainment as home brewers across the globe are laughing hysterically at me. I WILL succeed. If I have to levitate that cap in the bell... I will succeed.

 

[SDBob]

eBay saves the day.

 

[BeardedBrews]

The first prototype is going to be a monster. I'm looking forward to the rev2 where all of the low strain components and linkages shrink and begin to look like a commercial item.

Keep up the good work and don't forget to save that autocad as "super important thing for that really valuable customer" so your boss doesn't get suspicious

 

[SDBob]

Haha... you noticed. The first problem is I'm trying to fab everything from parts on hand as much as possible. 2nd problem is I'm not a fan of under-engineering, lol. Look at it this way, I can always use it to bend sheet metal or split wood when I'm not bottling.

Re-thought the magnet problem... came up with a solution powered by gravity.

 

[SDBob]

This is going to work!

 

[SDBob]

I've found there's a distinct difference how the caps behave on the carriage magnet in predicting their resting position based on whether the magnets used are axially or radially polarized. Axially polarized magnets tend to cause unpredictability. Not only do the caps stop at different points based on their approach velocity, but they also tend to 'tilt" the cap, particularly when backing the magnet away after it's positioned. Radially polarized magnets deliver predictable positioning, and hold the cap tight to the carriage, and keeps the caps steady while backing out. Making progress...

 

[SDBob]

Also considering adding a small 'cap wiper' into the carriage magnet assembly, to push all but the first cap back up the slide an 1/8" prior to the Bell coming down. Not sure yet if I'll need it...

 

[SDBob]

Rough cut the arm that'll hold the carriage magnet today. Have a big job I have to attend to, progress will slow this week...

 

[SDBob]

Well, I have to make tabs to attach a heim to the capper bell, and I'm ready to weld this contraption to the frame. 5 hours my arse!

 

[SDBob]

hopefully video late tonight of linkage working...

 

[SDBob]

Slight delay. Design flaw #483 was my arm that was tasked with placing the magnet at the end of the carriage, which has to pivot away as it approaches the bell, lacked enough "meat" for a proper bushing, and was destined to bend if I looked at it wrong. I ended up having to make a new arm, much stronger and with little play on it's axis. In the process of fitment, too much material was removed from the edge of the carriage, and now the caps flip up instead of staying flat. JB Weld is going to fix this with a little aluminum arch. Need a few days before I actually weld tabs and test run. The good news is, at this point, I'm very confident it'll work.

The original 4 to 5 hours fabrication time estimate has been revised. Turns out the estimator made the once-in-a-lifetime (of an estimator) mistake of forgetting the zeros. 40-50 is probably closer.

The ROI on this project is estimated at 1800 years, witch is a conservative estimate based on my bottling volume and time required to manually position a cap in the bell vs loading the carriage. No estimates have been made on the level of embarrassment if it doesn't work. It's been fun... and challenging, so there's that.

 

[BeardedBrews]

Slight delay. Design flaw #483 was my arm that was tasked with placing the magnet at the end of the carriage, which has to pivot away as it approaches the bell, lacked enough "meat" for a proper bushing, and was destined to bend if I looked at it wrong. I ended up having to make a new arm, much stronger and with little play on it's axis. In the process of fitment, too much material was removed from the edge of the carriage, and now the caps flip up instead of staying flat. JB Weld is going to fix this with a little aluminum arch. Need a few days before I actually weld tabs and test run. The good news is, at this point, I'm very confident it'll work.

The original 4 to 5 hours fabrication time estimate has been revised. Turns out the estimator made the once-in-a-lifetime (of an estimator) mistake of forgetting the zeros. 40-50 is probably closer. View attachment 554303 The ROI on this project is estimated at 1800 years, witch is a conservative estimate based on my bottling volume and time required to manually position a cap in the bell vs loading the carriage. No estimates have been made on the level of embarrassment if it doesn't work. It's been fun... and challenging, so there's that.

Possibly my favorite project update of all time!

No shame in failed projects, this is a hobby after all. Glad you're still going to finish it, and based on the pictures to date I suspect yeast will be replaced by nano-bots before your materials fail due to use. I think you're golden on the 1800 years ROI.

 

[ClaudiusB]

No estimates have been made on the level of embarrassment if it doesn't work.

The impotent part "YOU TRIED",others never try.
I have done it 17 years ago for my capper.

 

[SDBob]

Well, I've still been going hard trying to get it to work. At this point I've solved every problem but the fact that a cylinder with a 2" stroke doesn't allow enough room to both effectively capture the crown and get out of the way. I think with a 3" stroke it would be a done deal at this point. But... this new linkage design is the closest I've come, so I'm going to stick it on and see what happens. It's starting to not be fun anymore haha.

 

[SDBob]

Some further experimentation has shown that this dog may still hunt. My carriage doesn't reach a steep enough angle to keep the caps sliding, but a 3/16 stainless roller placed behind the cap stacks keeps them moving. And if I lower the carriage magnet at just the right time I can get consistently good pick ups by the Bell magnet. Starting a weird love/hate relationship with this thing. I dated a girl like this once long ago for a short time. A very short time.

Edit: Roller doesn't work, going with air pressure...

 

[BeardedBrews]

I dated a girl like this once

Tall, rough around the edges, slightly unstable, several loose screws, and surprisingly heavy?

 

[SDBob]

Close! You missed 'very needy'.

But... I can now confidently say it's going to work. The ONLY problem left to solve is pushing the caps down the slide as I'm only able to muster a 19.5 degree slope. But I have an unused supply of exhaust air from the cylinder, it won't be a problem metering some of that to push caps.

It should clean up nicely. Now that I have the geometry right, I can make a new bell, some clean rear linkage, some shiny skin...

#InTooDeep #LipstickOnAPig

 

[SDBob]

One last part to make...

 

[ClaudiusB]

But... I can now confidently say it's going to work. But I have an unused supply of exhaust air from the cylinder, it won't be a problem metering some of that to push caps.

#InTooDeep #LipstickOnAPig

Air will work to move parts.. Air conveyors are used worldwide including our toy brewery.

 

[SDBob]

By the way, I had to narrow my carriage magnet using a 1/4" x 5/8" cylinder mag in a 3/8" aluminum rod, and I'm still only clearing the bottle by 1/16". There's NO room for error. I made an adjustable stopper rod to handle pushing it away at the very last moment before it reaches the bell, and I'm finally getting 100% consistent square pick-ups by the bell, which was by far the most difficult problem to solve. There's more mass on the perimeter of the caps, and they really really wanted to load crooked. In fact, even when loading the bell by hand, I have to be careful to square the caps.

I'm going to have to do more testing with respect to the air injection. I haven't tried it with a full carriage, weight and gravity might push all but the last 3 or 4... might just need a few jets.

ROI updated to 2200 years...

So now it's fab the air injection, clean up parts, weld frame, paint, and make skin. Fun is over. Video is still a few weeks out...

 

[SDBob]

Just thought of another problem lol. On the upstroke my carriage magnet is going to stick to the cap that was just crimped on the bottle, prematurely pulling it away. I need that magnet to stabilize the cap until the last second... gonna have to come up with a way to prevent that...

 

[SDBob]

Thinking I'll probably have to press in a piece of 1/2" stainless rod into the end of my aluminum counterweight. It's a strong magnet...

 

[SDBob]

Thinking I'll probably have to press in a piece of 1/2" stainless rod into the end of my aluminum counterweight. It's a strong magnet...

 

[ClaudiusB]

I'm going to have to do more testing with respect to the air injection.

If you can inject from both sides with forward pointing injectors and bottom would be ideal. Injecting air from both sides should work too. Plastic soda bottles are conveyed by air injectors at a high rate of speed.

 

[SDBob]

Test.

 

[BeardedBrews]

By the way, I had to narrow my carriage magnet using a 1/4" x 5/8" cylinder mag in a 3/8" aluminum rod, and I'm still only clearing the bottle by 1/16". There's NO room for error.

You could drop the bottle platform slightly as part of the assembly motion. I'd worry about clipping the top of a bottle if I got some off-spec reused inventory. Cleaning glass is not a fun way to wrap up the end of a bottling session.

 

[SDBob]

Yeah, wish I could. I'd need a 2-1/2 or 3" stroke cylinder to do that though. It's a rounded edge, and I think worst case it could clip on the cap. And I may be able to tweak a few more mm out of it.

Edit... I'm changing the geometry a little bit for the 100th time. I've gotten the caps to load perfectly, so leaving end position the same, but by trial and error I've found I THINK I can solve both the bottle clearance issue and the lack of tilt issue just by moving some of the pivot points... again.

 

[SDBob]

Update on my foolishness... I'm done messing with it. The latest linkage incarnation looks like the caps are going to slide on their own while getting 0.230" clearance as it passes the bottle top. I'm going to weld brackets and call it macaroni. There's still plenty of work to be done, fab and install guides for ram because it has a tendency to self-rotate, fab and install an adjustable stop rod for the carriage magnet as timing for pulling it away is critical to good pick-ups, fixing/replacing hacked components that were remodeled 38 times, paint, and skin. This will all take time. Until then... Cheers!

 

[SDBob]

It may not take as long as I thought. Welded on the linkage support brackets and started testing. The damn thing works, lol. Got fired back up and fabbed the guides and magnet stop, and remodeled the neck indexer. It's solid now, no need to hinge. Some lipstick and tuning and this dog is ready to hunt.

 

[SDBob]

Pro tip (from an amateur):

If, say just hypothetically, you're tapping holes in your aluminum cap feeder, and you're too thirsty to think straight, you may end up breaking a tap. Removing a broken and embedded 8-32 tungsten carbide tap from aluminum can be a treat.

Last year I watched a YouTube video from a user named Ave, a brilliant and rather funny shop kind of guy and worth looking up. He showed a technique to remove broken drills and taps from aluminum using a chemical called "alum". It's used for pickling. I bought some from eBay just to have it on hand in my War chest. Glad I did.

A few hours in a solution of as much alum would dissolve and boiling water, and the tap DISSOLVED leaving the aluminum unharmed. Make sure you use an aluminum pot LOL. I'm going to buy some more, and suggest any and all DIY guys consider having some on hand just in case.