Plans in Imperial Units (not Metric)

I modified the plans (see attached) to be in Imperial units. Please provide your feedback and/or improve upon it yourselves.

I found it extremely difficult to find a lazer cutter who would cut the shredder parts in mm. In fact, I didn’t find anyone at all. Every lazer cutter would only work in inches. This is important because “translating” from 3, 5, and 6 mm to inches produces offsets in the cuts by a substantial amount, too much for the required precision in the shredder.


Closing topic to avoid more confusion.
1 year later no one has confirmed successfully cutting their shredder with the files of this topic.


Trying to upload the file zipped.



Shredder converted to Imperial system (Inches)

Has anyone made more progress on this since June 2017? @jibbajamba @kslippers @soul11man @groundeffect

Looks good, but where is all the clicking coming from?

Thaks for you work, i start with the measures in milimeters i have problems because some parts hit each other but i solved refill the space with 1 mm sheet hand cutted, if I make more machines I will test the plans in the future.

I started to assemble the pieces posted above in Fusion 360, but they did not fit… some of the pieces were the wrong size (end plates not as tall as side plates), and some were missing holes that the end pieces need to fit into, I don’t have much time to devote to this, so I gave up pretty quickly.

I ordered imperial thickness steel (1/4″ and 1/8″), but I think since I’m short on time and have a Fadal VMC and water jet at my disposal, I’m just going to surface the steel to 3mm, 5mm, 6mm and cut out the pieces using the metric model for now…

I hope to build multiple shredders, so maybe for the next one I’ll work out the imperial version…

Great thread all… I’m hoping someone will test the all-imperial set soon… if not I may do so this weekend. I don’t have extra money to burn, but am on a deadline so timing make push me to just do it.

If anyone has time to assemble in Fusion360 or other software in the next day or two as @nwnorm‘s mentioned, I’d be really grateful…

Hi folks, has anyone cut these dxf’s yet? I am in the US (Pacific Northwest) and have a waterjet in my facility. I was going to special order metric thickness steel, or mill imperial steel to metric thicknesses (I also have a Fadal VMC on site), but if these imperial .dxf’s work, I will just order imperial thickness steel.

Has anyone assembled this model in Fusion or Solidworks?


These are plasma cut (sorry for the confusion). If you plan to cut your parts with oxygen or nitrogen laser they should come up pretty nice although in normal circumstances, laser and water cutting it’s quite expensive.

Please let me know how your shredder come out. If everything fits correctly we will add them to our official download files package

Wish you luck 😉

Those parts are laser cut? Or Plasma cut?

I’m asking because we are changing our plans yet again to have the remaining parts cut out of metric thicknesses, using a nitrogen laser, so I’m hoping those will come out nice. We know the guy who will be cutting them and he knows what we’re doing with them, so hopefully everything works out a-ok.

Unfortunately this also means that we won’t be the pioneers to test this fully imperial design in real life, so it will remain a theoretical fit for now.

We’ll be back with an update on our semi-imperial version once we get those parts in mid-April.

Thanks for the size substitutions, I’ll get to work on this as soon as I have some time available.
By the way, it doesn’t matter where you cut your files, it may be in California, In Mexico or in Tangamandapio, plasma cut will always give you awful results. If you want a nice, clean and shiny cut, the way to go is waterjet.
Just to give you an example, have a look at my plasma-cut shredder parts:!Asv5yaQakrNSgr0RRk9NALv4zCSvCA!Asv5yaQakrNSgr0VMWQN6-7GG9ctmA!Asv5yaQakrNSgr0TYvnP7MY5NdKG4g

I think that would work, I’d definitely be interested in hearing how it goes as it’s a great way to minimize the gaps (which my instinct tells me would be good).

@xxxolivierxxx and @jibbajamba and everyone else
My local plasma cutter option fell through after three months of back and forth — they finally tried cutting the parts and the quality was horrible for some reason.

Anyways, now we are having the rest of the parts cut in Miami, from imperial thicknesses, and so I have gone through the weirdness of editing all the right parts in the DXF files. I’ve designed them as if the cuts and thicknesses will all be perfect :X

Size substitutions are:

3mm >> 1/8″ (3.125mm)
5mm >> 3/16″ (4.7625mm)
6mm >> 1/4″ (6.35mm)

My starting point was the updated files from @keesdeligt, with the 1″ hex hole for the shaft, so these are entirely imperial. We’ve already had the 3/16″ parts cut, and acquired and machined the 1″ hex bar. They are a really tight fit but we’re planning to coax them together by freezing them a bit. We’re just ordering the 1/8″ and 1/4″ parts now, so we’ll be able to test the fit of the whole package by mid-April and will come back here with a report.

If anyone has the time / skill combination to double check my modified DXF files that would be awesome 🙂

@xxxolivierxxx I also have a lot of 3D printing and modeling experience, if you want any help or advice on that stuff I’d be happy to assist.


I purchased a 3D printer a few months ago and after some try and testing I believe I got enough 3D modeling knowledge to try and make the imperial units version of the shredder myself, however, I am not familiar with metal thickness in imperial units and their availability.

Could you please let me know the closest thickness in imperial units you can get to replace the 3mm, 5mm and 6mm metal sheets?
Once I get the different gauge/thickness values in imperial units I’ll work on adapting the current shredder design to inches.

@klroth025, your idea is one way to accomplish this. Myself, I have access to a metal “planer”, if you will, that will shave off up to .01″ off at a time. I plan to shave off all the knife spacers and their opposite fixed knives until I can get them to fit snuggly without hitting each other. I don’t know how many passes I’ll have to make, hopefully not too many.

If you take your approach, you’d have to come up with a clever way to get the knives to line up perfectly between the fixed knives. This may work if you use the same spacer between all the knives.


Since my last post, I have found companies that sell shims of varying thickness and size to create clearances. I also found that the company 2 doors down from where I work does 3D printing and rapid prototyping, so I will talk with them soon about how they can help to make a solid set of plans to work with imperial sized metals.


I had a couple of ideas that might be of interest, or you may tell me I’m crazy… we’ll see.

If all the blades and cutters were cut from the same thickness metal, a thin metal shim (or washer) could be used between each blade (fixed and rotating) to create the clearance needed for the shredder to operate. The thinnest sheet stainless that I have found is 30 gauge (0.0120″). This creates closer tolerances than the shredder made of metric metal.

With 5mm and 6mm parts, the clearances are approximately 0.0197″ (1mm split between 2 sides of the blades… 1mm = 0.0394)

If that works, how much would the cost of having these parts cut be reduced if all the parts were cut from one thickness of metal. The waterjet or laser could cut all the parts in one operation, instead of 3 operations on 3 different thicknesses of metal.

Of course, it would be no small task to adjust the dimensions of all the 3mm parts, the two 6mm side plates, and the axle to accommodate this… just looking for feed back…?

How do I view the Imperial Plans within SketchUp? Also, how do I export them to view the specific dimensions, so I can give it to a person who is going to cut the parts?

Thank you, i changed from viewing the page in mobile to pc, now it all works.

Will it work to make all of the knives and spacers out of 1/4 inch steel? I might have a line on discarded wood chipper blades that are 1/4 inch thick. I don’t know if they are stainless steel or not, but considering the original use, it should be an appropriate grade! I am not sure why some blades are supposed to be 5mm, while other blades and the spacers are 6mm. Could somebody that knows, explain the logic of the 2 thicknesses? What am I missing?