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[TUTORIAL] Home Made Auto Trimmer


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Submitted By: JipoSubmitted On: Today, 09:45 AMSubmitted In: Grow Room Tricks and Tips:Click here to go to tutorial


Alright for those who are a little on the lax, lazy, or just want to safe some time trimming this tutorial is going to go over how one can convert a simple inline duct fan into a auto trimming machine for a few bucks!! First the supplies needed.


1.)4,6,8,10, OR 12" Inline duct fan, must not be the plastic bladed types they will not work, if they do work it won't be very good!

2.)Gardners mesh or a screen with large holes of some sort, Don't be picky about this but something that will allow trim leaves to pass through without letting your fingers and buds get passed.

3.)a perforated bag, old lawnmower bag will work, canvas or burlap sacks will as well. Something that will let air pass through it but not trimmings as such.


Now the How-to Part of things,

1.) Take your fan and figure out which way the air flows, you want it to draw air from the top, blow it out of the bottom.

2.) Cut off as much of the housing as possible so you're as close to the fans blades as you can be, should be less then a 1/4 clearance just enough so the blades don't scrape against the screen/mesh

3.) Now take a little 300grit sand paper (more or less works as well, I have 300grit laying around my shop everywhere) Sand the edges of the blades to give them a bit of a sharp edge, doesn't have to be a razor but the sharper the better.

4.) Attach your screen/mesh to the top side. Metal duct tape works well, something thats not permanent because you will have to clean the blades every once in a great while. This screen will save your fingers and nugs from potential damage and make things much easier for you.

5.) Get a hose clamp, T clamp is preferred, it will hold better and be quicker to snap on and off. However a normal hose clamp will be just fine as well. Use that clamp to clamp your bag on other end of the fan, and take a step back and look at your creation, it should feel good.


Optional things

Making a Table to mount it into.

1.)Particle board, the cheaper the better, this is just going to get hacked up.

2.)Sawzall or giant hole saw, routers work pretty well too.

3.)Some legs, 2x4's are great if you have scrap lying around if not, get some broom handles or old table legs from somebodies garbage.

4.)2 part epoxy


1.) Take the particle board and saw your hole into it, the same Diameter as the inline fan, you may have to notch it for the motor depending on if its inside or outside.

2.) Attach your legs to the particle board, make sure its nice and sturdy, sometimes bracing in between the begs helps a lot, run a board along the underside edge from leg to leg, put screws in these and then use some of the 2 part epoxy to give it an extra hold around the seam.

3.) Coat the top edge of the fan in 2part epoxy, as well as the hole cut into the table, you basically get one shot at this because most epoxy cure and don't let go...

4.)Mount your fan from the underside so that the top edge is flush or as flush as you can make it, then attach the bag on the underside of the fan and BAM! trimming table complete.


Time to trim!

1.) Take your freshly cut bud and hang it for a few days, just long enough to let the trim leaves and fan leaves dry out a bit, some people like to leave it all on until its ready for cure, I never do, but most times very fresh trim isn't going to work to well with the fan either.

2.) Take all your buds and set them on the table, now place one on the mesh and slowly rotate it making sure the leaves are going through the openings and not bushing up. Everyone will find a different method to do this, none of them are wrong its what works for you.

3.) Get your pruning scissors, I know you thought you weren't gonna have to do this... well you don't but no auto trimmer is that perfect ;) If you're like me you want you're buds to look like this when you're all done.

Posted Image

And that just won't happen without some careful time spent with some scissors, But the auto trimmer will take about 70% of that time off your hands! Heres an example of one that just went through a auto trimmer.

Posted Image


Results will vary though depending on how close you can get that screen, remember the closer the better!!

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