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Multiple Beer Capper

  1. Feb 20, 2017 #1
    So I've been working on a home project of creating a movable, self contained, ergonomic beer small (3-6 GA) home brew kit. I'd like to be able to fill and cap 6 bottles at one time. I'm working on a prototype for the filling process but need some ideas for how I could apply 6 caps to six bottles at the same time. I've been thinking about a large lever arm that could be pulled down onto a fixed arrangement of bottles. Anyone have any other ideas here?
  2. jcsd
  3. Feb 20, 2017 #2


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    You need to research the existing single bottle hand operated devices. What is the mechanical advantage provided? How much force is required to operate? Multiply these together and by six and you get your goal force needed.

    If the force is larger than is practical by a single stroke type mechanism (say you find that the stroke is 7 meters or available materials are not up to the task) you need to decide on a multiple stroke arrangement. These will vary in complexity. You may find that six is not the most efficient number to cap at once based on a price/performance/complexity calculation. Alternatively, you may find that six is too small to justify the expense of the more complex device.

    You need to math before you tinker.

  4. Feb 21, 2017 #3


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    This is an engineering forum, so you will also need a reliable device to uncap 12 bottles at one time.
  5. Feb 22, 2017 #4
    Why? I wouldn't be opening 12 bottles at one time. Bottles and caps are purchased separately before they are filled.
  6. Feb 22, 2017 #5
    Yea, I know I need to "math before I tinker". My design idea is a lever arm that would exert a distributed force on the arrangement. Since it's been a while since I've done any machine design course work, what would a design like this need to consider?
  7. Feb 22, 2017 #6
    The design isn't that difficult, but I question if it should be done even if it was easy.

    I'm a home brewer, and I fiddled with a system to fill multiple bottles at one time. It created more problems than it solved. It wasn't that easy to get each bottle filled to the same level. Now, maybe you have already overcome that problem for filling. But I stopped, because it just wasn't saving me much time (even when it worked well), and there is just more stuff to clean and sanitize.

    If you have an automated approach for properly filling even one bottle at a time, to the right level, w/o overfilling/spilling, please share it - that would be advantageous, especially if it can handle different sized bottles with minor adjustment. For me, that was the main problem, having to attend to each bottle to get just the right fill w/o spilling. It's easy to get distracted, sometimes hard to see the level in a dark bottle w/o just the right light. That alone would be worth pursuing, IMO.

    Capping should be relatively easy. You've seen the bench cappers, right? Just gang six cappers together with one lever, with a base to load up six bottles. You will need some compliance in each to allow for tolerance differences.


    Getting the caps in place automatically would be challenging. You might need to make a strip to hold six at a time (magnets?), and these would be manually pre-loaded. But I just don't think capping 6-up versus 1-up is worth it. You still need to load and unload each bottle, and the cost will be at least 6x a bench capper (OK, maybe less than 6x if you combine some parts, but those parts will need to be 6x stronger). That's a big investment for limited benefit, IMO.
  8. Feb 22, 2017 #7
    My design for the filling process I think should work, at least on paper. I'll post more once I have a working prototype.

    Question: when applying a cap to a bottle, is the downward force more important or is applying an equal force on the sides of the cap and "smushing" it closed?
    I had an idea where I'd have an arrangement of bottles (2x3) fixed in place. Then rest the caps on top of the bottles. Swing a lever on top and clamp it down so the bottles and caps can not slide. Then I've thought about a gear and pinion set up, where you'd turn a fixed gear that would push a customized pinion into the bottles, essentially squeezing the bottle caps. (It's hard to explain this without a white board and going into too much detail).
  9. Feb 22, 2017 #8
    Take a good look at a bottle capper. The crown caps are flared out prior to capping, with ribbing so a straight down cylinder pushes those ribs in at the side, over, and around the lip of the bottle.

    As far as I can tell, the downward forces really are applied to the edges. That crimping action around the lip is what pulls the cap down to seal at the top. Maybe there is some downward force on the cap as well to assist, I don't know. Look at a capper.

    Are you trying to re-invent the wheel? Cappers are tried and trued, if you think ganging up six cappers is a benefit, go for it. But use the current capper designs - they work, since the late 1800's I think.

    Does your filler design automatically stop when each bottle hits the correct fill level? If you have not accounted on paper for different fill rates on each bottle, I can just about assure you that you will see this problem on your prototype. The automatic fillers at the home brew level that I've seen get mixed reviews, they get kinda 'tweaky'. That problem will be multiplied by six if you try to fill six at a time.

    I still feel you are providing a solution that doesn't really have a problem. Have you really thought through the advantages of a multi-capper? Think of it this way:

    A) Single capper:

    A1) Set filled bottle in place under capper.
    A2) Place cap on bottle.
    A3) Pull lever.
    A4) Remove bottle and place in box.
    Repeat 6x

    B) Six-up capper:

    B1) Set filled bottle in place under capper. Repeat 6x.
    B2) Place cap on a pre-load strip. Repeat 6x.
    B3) Place cap strip over the six bottles.
    B4) Pull lever.
    B5) Remove bottle and place in box. Repeat 6x.

    You have added one step for each six bottles (loading a strip of caps), and reduced 6 steps to one (pulling the lever). Three other steps remain unchanged. Compare the times for each (pulling the lever is maybe a second or two?). What are you gaining? At what cost, complexity, storage space?

    Have you actually bottled 5 gallons of beer before, or is this all based on assumptions?
  10. Feb 22, 2017 #9
    Yes, I've brewed before. I'm not looking to sell this device or solve any major problems, it's just a home project. I guess you're right, a cylinder coming straight down would be the simplest and cheapest option. The capper I have has two levers that push inward on the cap, and there is where I was wondering if a sideways force was required.

    My issue is filling every bottle by hand then capping each one individually can be frustrating, time consuming, and its not very ergonomic. Plus there are several issues I run into where not every bottle will be filled with the same amount, spills can (and have) occurred, bottle wands have potential to malfunction (the cap may fall off), etc. My filling process does not need to take fill rates into consideration based on the design I am using. My end goal is to place six bottles on a tray, open a few valves, fill the bottles, close the valves, slide the tray to the next station, cap all 6 at once, box 6 at once, then repeat. Having 6 bottles filled, capped, and packaged on an assembly line will most definitely save time.
  11. Feb 22, 2017 #10
    Sounds like you have a "wing capper" - that's what they put in the starter kits, and I found a bench capper is far easier to use. That will help.

    I just doubt that a set up with six valves and tubes will speed filling up much either. Yes, you could have the fill tubes all on a rack that lifts up out of the way, then set up 6 bottles (in a little indexing stand), then lower the tube assembly into the bottles. Then open valve #1, wait a few seconds, open valve #2, etc up to #6. You'll need to time it just right, so that by the tie you start #6, #1 is almost full. So then you fiddle with valve #1 to get the fill just right, but if you take too long, #2 is overflowing! And soon after, #3, #4.... I think you will find yourself juggling so much that it will just be a major pain.

    Maybe, two valves, and a cylinder in between that matches the volume you want in the bottle. Fill the cylinders with the bottom valves closed. Then close the top valves, and open the bottom valves to fill the bottles. But that gets complicated - you don't want air in the system (oxidizes/stales the beer), and you would need a valve to let air in to drain the cylinder. You'd also need different sized cylinders for different sized bottles (I fill a variety of sizes).

    And then, you have a LOT of stuff to clean. Most valves need to be taken apart to really get them clean and sanitized.

    I'd concentrate more on optimizing the set up for one beer at a time. Set up something to hold the bottle in place as you fill, that is quick/easy to clean if you overfill. Have a bucket to dip the bottle in to clean it if you do spill. . Set up a back light so you can see the fill level clearly. Have a convenient, sanitary place to hang the filler when you swap bottles, and catch any drips. Have a place to set the full bottles so they won't be tipped, just place a cap on them loosely while you fill the rest. Then cap them when you are done filling (advantage - they will outgas a bit of CO2, the caps will let it leak out, replacing most all of the CO2 in the bottle headspace). It's really not that bad once you get organized.
  12. Feb 22, 2017 #11
    Could you not just flush the system with sanitized water once the process was complete? Also, does air not get into the product in the time between fill and capping? You have a bottle filled with product open to atmosphere.
  13. Feb 22, 2017 #12
    There is a tendency for microscopic particles to get stuck in nooks and crannies. Sanitizer might or might not reach everything. In pro systems with Clean-in-Place, there are very specific designs to assure everything flows smoothly, nothing trapped.

    Yes, some air exposure occurs in bottling, but it is minor - you should fill at the bottom, residual CO2 is released, and some foam forms (bubbles of C02) to cover the surface. This CO2 is pushing out the air. But you want to minimize this as much as possible, so any air in the system just makes it worse. Maybe not bad enough to be a problem, but that is hard to measure at a home brew scale. Just best to avoid it as much as possible.

    But again, look at the process - will you really be saving time? Is it worth it?
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