STIHL PolyCut™ Mowing Head

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Product Description

This is a multi-purpose cutting tool with three thermoplastic blades that are ideal for hard-to-reach places and large areas of high-growing grass. The blades are mounted on bushings and extend when the engine is brought up to operating speed. The white thermoplastic blades are also ideal for trimming around monuments and other solid objects as they don’t mark the stone. The blades are easy to change and some models can also be fitted with flexible nylon line in addition to or in place of the blades.

A variety of cutting heads and blades are available. See Dealer for details.
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STIHL PolyCut™ Mowing Head is rated 3.9 out of 5 by 28.
Rated 4 out of 5 by from CONDITIONAL Recommendation! This cutter head kind of fits a niche between a Sting-Line trimmer & a Cutting Blade. I have used mine occasionally, but it sets on a shelf in my shop because the Cutting Blades better fit my uses. There are specific uses that it will fit just fine.If you are cutting weeds that look butchered or shredded when cut by a String-Line trimmer, this may be for you. Some hollow-stemmed or moisture-laden weeds cut well with this Poly-Cut Mowing Head. However, it will wear down quickly when introduced into woody brush. I had good results when cutting Canadian Thistle & Knapweed.
Date published: 2018-03-14
Rated 5 out of 5 by from Perfect for Boulder Walls and Foundations I love this product. Gets all the weeds growing at the bottom of my 100 foot boulder retaining wall. The string trimmer wouldn't survive and the boomerang blade throws too many sparks. The PolyCut blades get in every corner and wear down nice and evenly. With any other tool this job would take much longer.Be aware that after such heavy use you will need replacement blades every time. Along my foundation wall they last much longer.
Date published: 2017-09-09
Rated 5 out of 5 by from Good for tough weeds but.... I have been satisfied with performance overall on weeds that are pretty big--3 feet or more. However, I don't feel like it works the best on the finer, shorter weeds. I am planning on going to store and get the regular trimmer head and use the poly cut one when needing the really tough weeds cut.
Date published: 2017-09-03
Rated 1 out of 5 by from I can't get it on my km 90 r I can't get it on my km 90 r it doesn't fit but on the package it doesn't fit
Date published: 2017-07-28
Rated 2 out of 5 by from PolyCut blades not good Agree with prior post, when blades heat up they deform and get stuck inside head. Asked dealer if other blades available, no. Also need tool to change blades; have used another brand and could change with simple button push and blades were stronger. However will try adding short pieces of line mentioned in other posts. Stihl can do better.
Date published: 2017-07-22
Rated 4 out of 5 by from No Prickly Lettuce Tried this product on very tough weed; Prickly Lettuce. When that weed grows over a foot tall most weed eaters shy away. It can grow over 5 feet tall!!! At that size, it has a very woody stalk. The PolyCut Head can chew it up but not over long duration. Not recommended for tough weeds.But it holds it's own very well for what it's advertised to do.Trouble I had was when one of the thermoplastic blades got bent, the blade receded into the body and that made for imbalance so got lots of vibration feed back through the trimmer handle. I used it for several hours on heavily weeded areas without interruption.Better may be to get a metal cutter for the bigger badder weeds.
Date published: 2017-07-08
Rated 5 out of 5 by from Savage I went into the store to get a metal grass blade and was begrudgingly talked into this cutting head. I really had my doubts that it could handle my garden. I had massive weeds (>6' tall) and raspberry bushes. You couldn't walk through the garden. This mowing head went right through everything. It absolutely decimated everything in its path. This thing is a monster in all the best ways.Also, it is incredibly easy to swap between this cutting head and the string trimmer head that came on my FS-56.
Date published: 2017-05-15
Rated 5 out of 5 by from This thing is a BEAST! I bought one of these along with my FS-85 brushcutter 16 years ago, when I was moonlighting mowing lawns. Both the trimmer and head are still going strong. I use a short piece of.105" line along with the knives, and can pretty much cut all day without having to change strings. The flail knives make quick work of high weeds along ditches, and doesn't seem to throw as much debris as my Supercut head.
Date published: 2017-05-03
Rated 5 out of 5 by from Overgrown Weeds Used this cutter head to clear a path through an overgrown lot. 4' tall Canadian thistle, buckthorn, reeds, and Queen Anne lace, were no problem. Ran about 6' wide by 200-300 feet with no major signs of wear. Well worth the price
Date published: 2016-07-28
Rated 5 out of 5 by from Great product when used with a single piece of .130 cutting line I use an 18 inch piece of .130 cutting line with the plastic blades. Need to force the line into the restrainer in the middle of the head with a screw driver. Use of the line prevents blade breakage when cutting next to rockeries, fences. Necessary to change the line when it wears down . I
Date published: 2015-05-03
Rated 4 out of 5 by from This product has pretty good features on it. its easy to use and very quick and easy to change the blades. I used this product over the summer last year at my job. I used it for about 2 1/2 months and i had to switch to a different blade. It cuts very well in thick and tall grass but it you hit a tree, rock, or piece of metal the blades get dull then break off. The blades are expensive for what they are. i can go through about 2 packs of blades in about 3 days where i work. I would recommend that if you buy this weed eater head you just cut where you know there's just grass and not rocks, trees or metal.
Date published: 2015-01-19
Rated 4 out of 5 by from very useful trimmer head This trimmer head came on my FS66 when I bought it in 1990. I'm stihl using both. This head will cut through heavier brush than you might think. It's a joy to use in light brush and tall heavy grass. Chain link fences, stone and concrete will wear down the poly-cut blades quickly. String trimmers work better around obstacles. It edges well but the blades wear down quickly on pavement. In tall grass run it at half throttle, take a shallow cut and swing it like a scythe. Take too deep a cut and tall grass will wind around the shaft and stall you out. No trimmer head is perfect but this is the all around most useful one I have used.
Date published: 2014-06-26
Rated 5 out of 5 by from What a great tool! I was so tired of trimming the tall grass by the creekside and having the string break or trying to find a place stable enough to release more string. I decided on the STIHL PolyCut Blade. I used it today for the first time and it cut right through the thick grass and blackberry vines like a hot knife through butter. I even hit a rock or two and a stump with no major issues. The blades are still very usuable even though I did purchase the replacement blades, I won't need to at this time.The blades won't replace the string for certain jobs but this job was done with ease and speed! Love it!
Date published: 2014-06-12
Rated 5 out of 5 by from Excellent for brush and grass My parents had one of these trimmer heads on a sthil brush cutter when i was growing up. I used it to mow fence lines, drive way banks, and trim around the house and barns. When i got older and bought my house i also bought a fs55r and when i picked it up from the dealer it had a string head on it. I dislike string heads so much i gave it to the dealer and had them install the poly cut head. I will never use another style of head on my trimmer. I get two or three trimming rounds at my 6 acre property from one set of blades.
Date published: 2014-05-16
Rated 5 out of 5 by from Good product! I use the poly head on an FS46C trimmer on my tree farm and around the pond. I cut things that are much heavier than what is recommended for this trimmer and poly head, but it whacks right through it. For such heavy brush I don't replace the poly blades as often as I would think I would need to. I don't cut around the pond a lot. I usually let it grow up because I know this tool will handle it.It's a testament to the quality of Stihl that I can use this residential trimmer/blade combo in a more commercial setting and have it perform at a high level.If I ever wear this one out I will go to a straight shaft commercial model, but 6 years in, this one has proven to be pretty indestructible.For this reason, I am a big fan of Stihl.
Date published: 2013-10-17
Rated 4 out of 5 by from Great upgrade from the auto feed string head I was frustrated by the design flaws in the auto-feed head. My dealer recommended this head. I am VERY pleased. It is durable and the blades last for many hours of use which translates to months for what I use it for.The blades are durable but not indestructible. They are great on grass, weeds and vines but are brittle and will break against fence posts and trees. I have brick flower beds that I have to trim around. I have to switch heads regularly.
Date published: 2013-09-24
Rated 1 out of 5 by from Not user friendly. Problematic. Hart to start.Frail. When it is working, not good for much more than very light grass trim.Hard to get plates apart to replace blades. Head falls off shaft when in use. Not reliable.
Date published: 2013-09-05
Rated 4 out of 5 by from Quick and easy to replace the line! I use it primarily for the line feature. Forget the auto-feed systems. The unit will accept the heavier line (.130) which is a plus. I recommend it to friend (72 years old) who has the auto cut and the trim cut. He is very happy now.
Date published: 2013-08-17
Rated 5 out of 5 by from Purchase this product to replace the AUTOCUT The Polycut head is way better than the Autocut head especially for tall grass and weeds, I would recommend this item to anyone who had problems with the Autocut head.The only drawback with the Polycut head is that you must stay away from rocks and tree trunks.
Date published: 2013-07-16
Rated 5 out of 5 by from I've owned a STIHL Polycut since 1980. I bought the STIHL Polycut Head for my FS 410 Brushcutter in 1980 for use on heavy matted grass. The Polycut works very well in heavy material and the blades are easy to change. I use this head regularly and the blade life is excellent! VERY GOOD value for the price.
Date published: 2012-12-16
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Instruction Manual - STIHL PolyCut™ 5-3 (PDF)
Instruction Manual - STIHL PolyCut™ 6-3 (PDF)
Instruction Manual - STIHL PolyCut™ 20-3 (PDF)
Instruction Manual - STIHL PolyCut™ 41-3 (PDF)
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