GonzoAcres
Active Member
sooo, after the initial sticker shock of most of the shredding machines I'd found online, and being a tinkerer and collector of useful stuff otherwise headed to a landfill (I think the commonly accepted term is "hoarder") I decided to take a long shot at modifying one of the several paper shredders I had sitting on shelves collecting dust. As with any effort to build or modify something that is similar to a purpose built manufactured product, the first step such an effort should be to drop any illusion that you will save a bunch of money AND end up with a device that accomplishes what you are hoping to accomplish as well as the product you are trying to recreate. Generally 90% of the time you are lucky if you end up saving money building it yourself OR creating something that suits your purposes as well as the manufactured product you are recreating, it is a very rare occasion that most amateur engineers accomplishes both... but if we didn't enjoy learning, experimenting, and otherwise doing things "the hard way", we wouldn't be growing our own tobacco now would we 
I must say I was pleasantly surprised that this build worked out as well as it did, and considering the end result was a motor driven shredder, the costs incurred were incredibly minimal, I believe I've spent a total of $40 dollars, not counting the value of the paper shredder, which I believe I purchased at a garage sale or thrift shop for around $30 probably 5-6 years ago, I didn't realize how good of a deal it was until I decided to look the model up on Ebay prior to writing this post so that I could give a more realistic costs accounting. The Paper Shredder I used was a Fellowes PowerShred PS 70, I couldnt find a whole unit on Ebay, but a refurbished motor, gear assembly and cutter head assembly is available Ebay currently for about $210 delivered to Colorado... I'm inclined to believe most paper shredders would be fairly straight forward to modify in a similar fashion but I havent taken many others apart so I cant be sure..
The jist of this build is simple, how to make a machine thats exactly like a paper shredder, but is equipped with cutter heads that produce a finer shredded end product, so i looked around for round items that were similar in thickness to cigarette tobacco, there was a dime sitting on my desk, and it looked about right, so I thought, I wonder how thick a standard fender washer was, i'm still not sure but its pretty close to the thickness of the tobacco I prefer in my smokes, which is closer to 1.2mm than the .8. so after a quick mock up with washers I had on hand and a section of 7/16ths mild steel rod I had, i decided it was worth a shot.. off to the hardware store to pick up washers in 2 sizes, both with 7/16ths ID, found a box of 50 1.25"OD zinc washers (I know zinc is bad for you, not to mention not exactly the toughest material for this application) the box of 50 7/16" ID X 1 1/4" OD washers came out to 6.49+ tax, unfortunately the small neighborhood hardware store didnt have any 7/16ths washers in a smaller OD, but they did have Nylon washers with a 7/16th ID and something like 3/4" OD, but they didnt come in boxes and ran like $0.35 each... so I took all they had which was 53... got home, and put all of the larger zinc washers on to the 7/16ths rod i had and took em over to my bench top belt sanded to make sure the edges had nice crisp 90 degree corners on them, I just held the shaft over the belt sander and let the washers spin as they mad contact, until the whole column of washers had a uniform newly cut outer edge, I cut the shaft about 3 inches longer than the space taken up by the 50 washers stacked tightly on it, and then cut another piece the same length, which was about 6 inches, then I took apart paper shredder, and removed the paper cutting heads that came with it, to determine how the shafts engaged the gearing assembly, both were pretty straight forward to shape into the new shafts I would be using with an angle grinder and a file. next was to test fit everything, so each shaft was stacked with one small washer and one big washer until i had no more washers, each shaft was inserted through the bushings that held the shafts and the opposing piece that held the other end of shafts was slid on, and wa-la motorized tobacco shredder, I did go back and restack the washers on the shaft with a small amount of epoxy to the center hole of each washer to adhere them to the shaft and each other in hopes of avoiding them simply free spinning on the shafts, so far thats been enough to keep that from happening. If it becomes an issue i'll either cut a keyway in to the shafts and corresponding notch in each washer with a file or a cold chisel to ensure the washers are always physically engaged with the shaft as it spins.
Apparently videos can't be uploaded but here's link to a video of it test running, https://photos.app.goo.gl/9zmJWERfWuy777Am8 I havent gotten to attaching combs or brushes yet, they are absolutely necessary, but I purchased some stiff nylon bristled "tile and ground" brushes for a couple bucks each that seem to work ok at clearing the shredded tobacco from the cutter disks, just haven't figured out how i'm going to mount them in place yet.. will post a video of completed project as soon as I finish it up..
Side note, in any project that requires you to use washers where there arnt specific specs to be met, several years ago a contractor on one of the jobs I was on pointed out that in a pinch or just to save money, in most instances washers actually cost more than the value of similar sized coin currency, just something to consider next time you are standing in a hardware store irritated that a zinc washer the size of a dime ( which also happen to be made out of zinc) is being sold for 18 cents....
I must say I was pleasantly surprised that this build worked out as well as it did, and considering the end result was a motor driven shredder, the costs incurred were incredibly minimal, I believe I've spent a total of $40 dollars, not counting the value of the paper shredder, which I believe I purchased at a garage sale or thrift shop for around $30 probably 5-6 years ago, I didn't realize how good of a deal it was until I decided to look the model up on Ebay prior to writing this post so that I could give a more realistic costs accounting. The Paper Shredder I used was a Fellowes PowerShred PS 70, I couldnt find a whole unit on Ebay, but a refurbished motor, gear assembly and cutter head assembly is available Ebay currently for about $210 delivered to Colorado... I'm inclined to believe most paper shredders would be fairly straight forward to modify in a similar fashion but I havent taken many others apart so I cant be sure..The jist of this build is simple, how to make a machine thats exactly like a paper shredder, but is equipped with cutter heads that produce a finer shredded end product, so i looked around for round items that were similar in thickness to cigarette tobacco, there was a dime sitting on my desk, and it looked about right, so I thought, I wonder how thick a standard fender washer was, i'm still not sure but its pretty close to the thickness of the tobacco I prefer in my smokes, which is closer to 1.2mm than the .8. so after a quick mock up with washers I had on hand and a section of 7/16ths mild steel rod I had, i decided it was worth a shot.. off to the hardware store to pick up washers in 2 sizes, both with 7/16ths ID, found a box of 50 1.25"OD zinc washers (I know zinc is bad for you, not to mention not exactly the toughest material for this application) the box of 50 7/16" ID X 1 1/4" OD washers came out to 6.49+ tax, unfortunately the small neighborhood hardware store didnt have any 7/16ths washers in a smaller OD, but they did have Nylon washers with a 7/16th ID and something like 3/4" OD, but they didnt come in boxes and ran like $0.35 each... so I took all they had which was 53... got home, and put all of the larger zinc washers on to the 7/16ths rod i had and took em over to my bench top belt sanded to make sure the edges had nice crisp 90 degree corners on them, I just held the shaft over the belt sander and let the washers spin as they mad contact, until the whole column of washers had a uniform newly cut outer edge, I cut the shaft about 3 inches longer than the space taken up by the 50 washers stacked tightly on it, and then cut another piece the same length, which was about 6 inches, then I took apart paper shredder, and removed the paper cutting heads that came with it, to determine how the shafts engaged the gearing assembly, both were pretty straight forward to shape into the new shafts I would be using with an angle grinder and a file. next was to test fit everything, so each shaft was stacked with one small washer and one big washer until i had no more washers, each shaft was inserted through the bushings that held the shafts and the opposing piece that held the other end of shafts was slid on, and wa-la motorized tobacco shredder, I did go back and restack the washers on the shaft with a small amount of epoxy to the center hole of each washer to adhere them to the shaft and each other in hopes of avoiding them simply free spinning on the shafts, so far thats been enough to keep that from happening. If it becomes an issue i'll either cut a keyway in to the shafts and corresponding notch in each washer with a file or a cold chisel to ensure the washers are always physically engaged with the shaft as it spins.
Apparently videos can't be uploaded but here's link to a video of it test running, https://photos.app.goo.gl/9zmJWERfWuy777Am8 I havent gotten to attaching combs or brushes yet, they are absolutely necessary, but I purchased some stiff nylon bristled "tile and ground" brushes for a couple bucks each that seem to work ok at clearing the shredded tobacco from the cutter disks, just haven't figured out how i'm going to mount them in place yet.. will post a video of completed project as soon as I finish it up..
Side note, in any project that requires you to use washers where there arnt specific specs to be met, several years ago a contractor on one of the jobs I was on pointed out that in a pinch or just to save money, in most instances washers actually cost more than the value of similar sized coin currency, just something to consider next time you are standing in a hardware store irritated that a zinc washer the size of a dime ( which also happen to be made out of zinc) is being sold for 18 cents....
