Brush cutter head

[mzt]

Hope this is Mad enough.     




Made this thingy a few years ago: the idea came from a commercial item I saw for sale at a laughable price. It was made of plastics, and had the 'blades' attached through a single pin.
Having them attached on both ends helps a lot WHEN (not IF) they snap.

-- USUAL DISCLAIMER APPLIES --

I mean, that can be really dangerous (though safer and easier to use than the cutting disk, especially when there's tall grass mixed with bushings, IMHO).




The six hardened steel pins were kindly supplied by an old VHS player and cut to length by making use of a thin cut-off wheel(*) on a Dremel.

(*) OK, more than one.

One end of the pins was slightly ground tapered on the lathe (to ease their forcing down into position).
There might be safer ways of doing that, than a hand held Dremel while the pin was spinning into a collet.
No wheels were broken, tho.

 
Complete!
Ready to be tested on the field.






A snapshot of my beloved hydraulic press, showing the head with the hardened pins already forced into position.





The 8mm rod showing at the bottom of the head was used to keep the body and cover aligned, while forcing down the pins in the press.


Another view of all the parts.




Marcello

[fixerup]

 
That will certainly do some serious brush cutting. I'm curious to know what size of brushing it will cut.
 Thanks for posting.
 
Phil

[mzt]

Well, I found trees while clearing them.
'nuff said.

Marcello

[Brass_Machine]

 

Yup. That is mad. Well done, but mad none the less.

What was it mounted on?

Eric

[Jonny]

Thats different, intrigued is it on a big Husky or big Stihl?

Can cut through 1 1/2" diameter with Danarm TH34 Kwacka engine and standard cheap blade £9.

[mzt]

That's a 30cc efco 8300. A bit taxing on the machine, but I've never had issues in years of use.

As for the blades in the previous pictures, they're chunks of worn out chainsaw blades facing their final re-use. Next, I can only think about the metal recycler.
After using them for a while, I decided that grinding away the now unused cutting teeth gives more duration.

My bushes are rarely thicker than 3/4", I don't think there were any 1"1/2.
If You're really curious about that head eventually cutting them, please, let me know. I will happily let 'em grow they reach the required thickness.
Won't be quick, but we will know for sure in a few years.

Marcello

[Jonny]

The thing that concerned me is the weight of the three blades, centrifugal force etc.
Putting strimmer head on with twin nylon before its cut to lengths, i really notice a lack of response, takes ages to build up speed. When cut to lengths by the guard clipper, it revs a lot more freely. Broken nylon or one nylon broke off it revs pretty instant.

One thing i did notice straight away was engines willingness to rev quickly when the cheap 3 pronged HSS blade was bolted on. Dont last long though so a file joby needed after use. Similar to these, think 10"? http://www.ebay.co.uk/itm/PETROL-STRIMMER-TRI-ARC-BLADES-X-5-FIT-RYOBI-JCB-BRUSHCUTTER-/180864428454?pt=UK_Home_Garden_GardenPowerTools_CA&hash=item2a1c5c29a6
Bought for clearing rhodadendrum bushes and bracken interlaced in to. Known the bushes twenty years they were too large then, how old no idea. A lot of the work i used my Dewalt 18v repo saw as i had the two chainsaws took off me

Just came across this http://www.ebay.co.uk/itm/BROGIO-BRUSH-CUTTER-WHIPPER-SNIPPER-HEAD-LINE-TRIMMER-METAL-BLADE-BRUSHCUTTER-/300668802237?pt=LH_DefaultDomain_15&hash=item460141d4bd

[mzt]

Nylon wire heads definitely have a quicker response. I rarely use the rotating chainsaws at maximum speed, they do a fair work at about half throttle.

The three-arc-blade-brushcutter in the first link is what I called 'cutting disk'.  I have one, maybe it has four blades, but never used it since I made the new head: never liked the tendency it had to screw itself into the thick bushings and pull the cutter from my hands when they were to thick to cut. A real pain to use, when they were mixed with tall grass.

The brogio cutter of the second link maybe more durable than chainsaw portions, not that I could not fit ordinary chains to my head. Never tried.
Sure it comes at a price.
Last but not least, making my own head gave me a good excuse for a couple of free afternoons in the shop. "Priceless".

Marcello

[Jonny]

Not knocking it Marcello, far from it.
Just pointing out it probably needs to bea  much bigger engine to power. Unless you wait for it to build up speed.

I might try one two pronged hardened steel around 250 to 300mm dia.

[redhunter350]

Hi all I notice it has been pointed out by Mzetati that this device could be dangerous but I would point out it can be fatal.

There was an accident close to where I live last year with just such a device -- some men were clearing rough ground and a link broke  on a similar commercially made unit, the link killed a man who was some 60 yards away from the person using the strimmer.

Needless to say these units are no longer in use by the contractors and a warning was issued by the coroner of the dangers of these units.

A tragic accident but if you do choose use it make sure there is no one within 200/300 yards when using or better stick to a blade or line!!!! 

[mzt]

Lines are no use among strong bushes, and blades break too when threre's stones among them. Having nobody within hitting range is a rule nobody should break.
Wearing proper equipment, too.
YES, them rotating chainsaws are scary.
I've had several links snapping: being attached on both ends prevented (note: prevented, not prevents) them from flying from the head.
Of course, as soon as I felt one of them was snapped (and good news are You feel the difference in no time) I replaced the broken link with a new one.
Nothing would prevent a link pin from bulleting in whatever direction, of course: using them at the minimum required speed (which is far below the max revs) moves the needle a bit towards the 'safe' side on the dial, without leaving the red zone.
I would have troubles considering that thing "safe" if it were locked in a drawer.

Thank You for the heads up.

Marcello