help building a tree trimmer.

[oughtsix]

If it was a belt drive unit, I would think you would need a tensioner between each shaft. But, probably not with a chain driven unit. But again you might, or you will get a bunch of chain slap.

Your sprocket / pulley sizing, along with the mating to a properly sized pump will take some calculating.

Since the blades are offset, would you run the sprockets / pulleys offset also, using a dual drive?

Hmm... start with lawn mower spindles or something like them with a dual pulley on one end of the shaft and a saw blade on the other end. Make the booms out of two long pieces of tubing about a foot apart connected together at each end. Make a carriage for each spindle that slides over the two pieces of tubing and mounts the spindle between them. Make a similar carriage for the hydraulic motor.

Slide the motor/carriage on the pieces of tubing first. Then slide each spindle carriage on the pieces of tubing putting a belt on each adjacent set of spindles. Slide springs on the pieces of tubing between each carriage to tension the belts. Attach the last carriage to the cross brace at the end of the pieces of tubing (The cross brace that holds the pieces of tubing 1 foot apart). When the boom is in an upright position gravity will pull each carriage down increasing the belt tension. The motor carriage would be free floating on the pieces of tubing on the bottom of the boom.

Use lawn mower blades or saw blades, which ever you prefer.


My table saw runs at 3000rpm and produces a pretty smooth cut. Mower blades run in this same speed range.

This hydraulic motor looks like it should turn your crank.
Surplus Center - 1.89 DYNAPOWER/STRATOPOWER PISTON HYD MOTOR

 

[Jim Shooz]

If you're REALLY serious about trimming your trees you could build one of these.
We have a miles and miles of shelterbelts, mostly Cryptimeria (sp) around the Kiwifruit and they need trimming every year. The blades total about 12' and they take a second sweep to 24' then turn the cutting head horizontal and top them. I've no idea of the mechanicals.
My problem now is that I've got to clear it all up (300Yards) before I can get out the drive. The mulcher which is roughly a big brush hog with its own V10 diesel driving a flail can't get here til Wed.http://www.tractorbynet.com/forums/images/smilies/mad.gif

 

[tpulley]

Jim the link didn't work.

JJ I really like the Sabre you posted. I would like to save myself atleast half of the $1400 or so they wanted for the Sabre unit.

 

[Jim Shooz]

Looks like I haven't learnt how to upload

 

[tpulley]

That thing looks like a scorpion with a huge stinger.

 

[92b16si]

did you build this yourself or where did you get that machine that thing looks sweet ,

 

[forgeblast]

I think that would be awesome vs zombies too...lol

 

[Jim Shooz]

No. There are a couple of them in the district built and operated by local contractors. Friday was the day they did my neighbours place which happens to be my front drive. That one is built on an old Fordson very heavily reinforced. Armoured glass all round. It has done some very long, hard hours.

 

[92b16si]

How much do you guys think it would cost to build something like the bobco