Brush blade recommendations for a FS90

[thatguy]

I got a Stihl FS90 trimmer (w/ bicycle handles) for Christmas.. I want to add a blade to it for cutting brush, heavy weeds

Looking at the Stihl website they have a few cutting blades and circular saw blades ( Trimmer Blades Trimmer Cutting Heads & Blades | STIHL ) - Any suggestions?

Do i need a different deflector if i use any of the cutting blades? The circulare saw blades seem to require limit stop deflector?

Why are the different deflectors needed?

Brian

[Oldstuff]

I have cut weeds, woody brush and trees up to 3 inches for years with blades on "weed eater type" tools. I do not have a Stihl, I have a Tanaka and have used blades for thick type of brush/weed and that #4 tooth grass cutting blade works best. For brush cutting the saw toothed blade gets clogged up with the debris. But on anything hard and 3/4 inch or larger the scratcher saw toothed blade is best.

Oldstuff

[thatguy]

Thanks Oldstuff, I appreciate your input.. I never gave much thought to the various types of blades and what works best on which type of grass/brush

Any other thoughts

b

[smstonypoint]

Any other thoughts

b

In my experience, the chisel tooth blades dull quickly. I am no great shakes at sharpening and can't duplicate the sharpness that comes with a new blade. I gave up on those blades and use a lightweight chainsaw to cut brush larger than 1" or so in diameter.

I now use steel brush knives for the smaller stuff. They don't dull as quickly, are easier for me to sharpen, and do a better job of mulching brambles, saplings, etc.

Steve

[Furu]

The three- blade brush knife works very well on diameters up to one inch. Stihl safety requirements say you need the bike bars and harness rather than the loop handle to use the metal blades. Don't know what you have on your 90 but I have untold hours with a FS 250 and FS 450 and can tell you the safety requirement for the bike handle/bars is there because of rebound if you hit heavy stems that do not cut easy. The harness and bars make it nearly impossible to have the blade bounce back and get your foot. Safety first in what you do will prevent lots of pain and rehab.

[thatguy]

Thanks.. Mine has the bike bars..

doing some research online today and some ppl recommended the Forester blade that has the chain saw teeth welded to it like this:

FORESTER 9 Saw Tooth Brush Blade Trimmers And Brushcutter Brush Cutter Brush Cutter Blades

Is this overkill unless you are doing a LOT of large diameter stuff?

b

[thatguy]

Let me add.. Any thought on OEM Stihl vs aftermarket 3 blade brush knife?

The aftermarkets are 1/2 price, but if it ony last 1/2 as long I havent gained anything LOL

b

[Furu]

Here in the PNW the Forester brand three blade knife is within one dollar of the Stihl. I use the Forester brand on the FS250 and the Stihl on the 450 as I have not found the Forester in the size I need for the 450.
There is a Champion brand carbide tip chisel blade I like versus the Stihl chisel tooth (I hate the sharpening). The carbide doesn't need sharpening but unlike the ads for the Champion if you hit rock you will shed a carbide tip and if you hit a steel post you will shed all carbide tips instantly and the blade is junk. I still use them because the no sharpening outweighs the times I screw up and shed teeth. The cost on those blades is within less than two bucks of Stihls chisel tooth. I have no experience with the chainsaw teeth blades.

[thatguy]

Troven Foresty - What are you using the 3 blade knife on? And what do you use the carbide tipped blades for?

Brian

[Furu]

I tend to prefer the 3-blade knife when I can get away with it as the result is more of a mulching effect than with the chisel. About the only time I use the chisel blade is on hard wood stems above 2 inches in diameter or when doing specific thinning of trees up to 5+ inches. Bigger than that does not work well and better to use a chain saw for thinning. I use the knife on almost all kinds of brush from ferns to Himalayan Blackberry, Evergreen blackberry, Salmonberry, Elderberry up to 2-3 inches, Devils Club, young Vine Maple that has not hardened off yet, grasses and weeds of coarse texture, etc. Not much that the knife will not work on. When the stem get too large it will take 3-4 "bounces" of the knife to complete the cut. Never use the knife in a sawing continuous contact style. Much better to keep it moving even if in a bounce/recoil fashion.
I have used the chisel blade on Himalyan Blackberries when the stems get really large in diameter (> 1.5 inches) but it cuts so cleanly that it does not cause as much "shock" to the plant and the result is faster regeneration of the stems so again I prefer the knife. I have tried just about every combination that I can think of.