Author, Publisher, Developer, Stitchcoder


I call it the Bagger 2000

I promise that some day I will write about something other than making kits, but for now that's what I'm all about. Today I'm pleased as punch about my new semi-automatic small parts bagging tool, which I call the Bagger 2000 (because it holds and fills 20 bags at a time, and because 2000 is a hundred times better than 20 as a model number).

The issue is this: we need to fill hundreds of 2" x 4" poly bags with lots of little nuts, bolts, and small plastic parts. Each bag gets a dozen or more different parts, and sometimes a dozen or more of one particular part.

We had been doing this using a batch of 20 pill counters (small trays with a trough on the side, designed for counting out pills in a pharmacy). This works, but it is tedious, and the sides of the trays are very low, meaning there is a constant danger of a part getting knocked out before it's emptied into the bag.

What I wanted was some kind of system where I could drop parts directly into the bags using a funnel, or something like that. But it would have to be 20 funnels, one for each bag in the batch, and I couldn't think of a good idea for how to hold the bag onto the end of the funnel, how to hold up the funnels, and so on. Until I realized that I own a laser cutter and have been practicing my inventing skills.

Here is the result: the Bagger 2000!

Being made entirely of clear acrylic, this object is actually quite difficult to decipher from a photo, so here's a short video that gives a better idea of its three-dimensional structure. There are 20 individual rectangular funnels: at the bottom of each, the acrylic sides have been bent around to form little upwards-pointing hooks.

To use the device, you flip it upside down and load it with 20 poly bags. The acrylic clips grip the zip closure on the poly bags. Flip it back right-side-up and you have twenty bags hanging underneath 20 funnels.

You can drop items directly into the bags. Here I've added the screwdriver and wrench included with most of the kits:

But dropping things straight into the bag is not ideal, because (a) it's very hard to recover if you accidentally drop in too many, and (b) it's hard to double-check that you got the right number, for items where there are multiples. (E.g., did I just drop in 3 or 4 of those tiny screws?)

What's needed is a staging area where items can be laid out in plain sight, before being dropped down into the bag. My big breakthrough on this project was realizing that the semi-automatic parts counter (described in an earlier blog post) was perfect for this job. The funnel array has exactly the same dimensions and spacing as the parts dropper, so when the dropper is placed on top of the funnels, they line up perfectly.

Here is a video showing how an assortment of different lengths of screws (manually counted and placed on the parts dropper) can be inspected before being dropped:

Here's a side view showing how the parts are guided down into the bag.

Basically this is the exact equivalent of a German "inspection toilet", which includes a special staging area to hold your you-know-what before it gets flushed down to the big poly bag at the end of the pipe. (They do this because they think it's important to inspect your you-know-what for any signs of health or diet problems every single time. Yes, this is for real, though becoming less popular over time, as I understand it.)

Where the Bagger 2000 really shines is when it's combined with the parts counting feature of the parts dropper. Here the parts counter, positioned on top of the Bagger, is being loaded with 16 hex nuts for each bag. You just wipe a pile of nuts over the counting plate.

Then, after double-checking that all the holes in the template are filled, you simply pull back the gate and presto-magic, all the nuts are dropped perfectly into their respective bags. 320 nuts (16 times 20) counted and put in bags in about a minute!

When the bags are finished, you just pick them like ripe fruit from the underside of the Bagger:

This machine has at least doubled the speed of filling the average kit bag, and I think it will also contribute to a lower error rate.

I'm just about ready to start wondering how other people solve similar problems. My approach to learning about a new area is often to try to do it myself first, without looking too closely at how other people do it. Then, when I feel like I have a really good handle on what the issues are and where the difficult problems are to be found (i.e. what have I not been able to figure out myself), then I'll do some research. Usually I find out that there are much better solutions, but I feel it's worth doing the messing-around phase first, because that's the only way I can properly appreciate how clever the better solutions are.

Theodore Gray4 Comments