Chipper Mods

[Short Game]

If I had it to do over, I'd never buy this chipper, but now I've got too much time and work invested and must go with it. Too late, I discovered that it was not only not what I would have wanted, but it wasn't well made either. It was the most I had ever spent on any implement ($2,300 back then), and was poorly constructed. The first set of belts failed very soon, as the double pulleys were misaligned by over an eighth of an inch. The reliefs on the flywheel for the double edged chipper blades were not true and the second edge of the four chipper blades were all damaged when tightened in at the factory. In other words, new blades do not fit properly. Maybe I just got a lemon, but it's clear to me that they make lemons.

Crary wanted another $800 at the time (8 years ago) for the blower. I had seen one that was in use and its case was covered with stress cracks, so I decided to build my own and make it stronger. I had initially intended to even build my own impeller, but I don't have a machine shop, so I decided to just buy Crary's as a replacement part. That was the first awakening to their poor standards. The impeller's center bore was several thousands over the one inch it was supposed to be. Worse than that, the bore was 3/32" off center, creating a 3/16 eccentricity and an intolerable imbalance. I mounted the impeller on the shaft and turned it against a grinder for a long time to get rid of the eccentricity. The balance improved, but due to the over-bore, it will never fit my one inch shaft correctly. My workmanship was far superior to theirs.

It's easy to see now why the one I had seen in operation was full of stress cracks. I went back to the dealer to inform him of the problems with the part. His store was busy and full of customers and he went off on me in a rage, deriding me for not buying the Crary blower in the first place. I hate having to go in there for anything now but he is also my local Stihl dealer. I know that my blower is way better than the one they sell. Over the years I've met a lot of people who would not do business there. Now I know some of why.

With pretty crude tools, this is what I was able to come up with:

The end plates are 3/16" and the frame that joins the chipper is 2X6X1/4" angle iron. The bearing blocks are several grades better than the stockers. I added an inspection/clean-out plate. Forming the curved part of the case from 1/8" plate (twice the strength of the factory made one) was my biggest challenge. I formed the funnel (also a challenge, forging and welding) to connect to that 4 inch conduit sweep. I braced it from the top of the shredder hopper. I made the blower belt guard the idler arm behind it.

I strengthened the 3PH framework and added the mount for the long trailer hitch assembly. The hitch design allows me room to work and feed the chipper hopper.

The extended hitch can lift the trailer wheels well off the ground and lets me empty it easily.

 

[Combustix]

nice mod, I need to figure something out for my Jinma. Needs extra help getting the chips out.

 

[RoyJackson]

That's very surprising about that Bearcat chipper/shredder. They have a very good reputation.
I have the same chipper/shredder (mine was marketd by Woods as the 5000) and have had no problems with mine whatsoever.

I do like that extended trailer hitch!

 

[Short Game]

That's very surprising about that Bearcat chipper/shredder. They have a very good reputation.

I guess everything I got from them was made on a Monday morning or a Friday afternoon.

The latest mod I did was to put a 45 degree grease zerk on the drive side main bearing. I just greased it for the first time because there was no way to get a grease gun to it until then short of disassembling the idler.

I don't know if it's noticeable, but the hitch extension is pinned in place so it can be removed in seconds.

 

[RonMar]

nice mod, I need to figure something out for my Jinma. Needs extra help getting the chips out.

It does? Are you running it at the full 540 PTO RPM? Do you have the chipper blade to anvil distance set properly? At full RPM, mine has absolutely no problem blowing the chips out many feet. It moves a huge ammount of air thru the rotor. The only time I have experienced any ejection problem is when I allowed the ROTOR RPM to droop. Throttle friction comming loose, chipping too large a piece, or the blades getting dull can cause this. The most important piece of advice I received when I picked up the chipper was to properly set the blade to anvil gap. Blades set at too large a gap between blade and anvil plate will cause it to take too large a bite and will bog the rotor RPM down. Blade to anvil gap on the Jinma 6" chipper should be between .015" and .030"(15-30 thousandths of an inch)...

 

[studor]

I have that same Crary chipper that I bought used and so far it has been great except the blower would be a wonderfull addition. I really like the mod you did and have access to a machine shop. I have never seen one with the blower kit and my local dealer would only order one with a confirmed order. How did you figure out the detail required to build it?

 

[RoyJackson]

I have that same Crary chipper that I bought used

How did you figure out the detail required to build it?

Crary is actually Bearcat.
If you want an idea how to build a blower for your chipper/shredder, go to the Woods Equipment website a look up their manuals for the Woods 5000 (which is actually Bearcat built). They have an operator's manual for the optional blower which may give you some ideas.
FYI, if you buy a blower, it'll set you back about $1000.00. I priced one (a Woods, actually) last year.

 

[Short Game]

I have that same Crary chipper that I bought used and so far it has been great except the blower would be a wonderfull addition. I really like the mod you did and have access to a machine shop. I have never seen one with the blower kit and my local dealer would only order one with a confirmed order. How did you figure out the detail required to build it?

Well, I only saw the outside of the one in use at a shopping center. The guy they contract to do their landscape work had it and I talked to him on a couple of occasions. Like I said, his blower case was cracking up. It looked like 1/16th inch sheet metal.

I got the one inch shaft from a scrapper friend and started from that at one end, and building the frame, beginning at the outlet flap hinge at the other. From there it was just measuring and acquiring the impeller fan, pulleys, and bearing blocks. I robbed an idler wheel from a dead rototiller. The rest is scrap steel I had. Forming and welding was just as-you-go.

I have learned that it will clog up with wet and/or punky material (the same complaint I have read at forums online with the factory setup). It frequently clogs the outlet pipe if I use the shredder. The shredder makes splinters and sticks that will catch on the slightest thing and then it all piles up behind the jam. I have never liked using the shredder anyway. It's too grabby -- dangerous, if you ask me. What I want is the green chips and the chipper and blower work great for that.

So, if I had it to do over again, I would have just gotten a chipper that blows the chips itself. I really don't need a shredder. Live and learn.

The guy at the shopping center told me he seldom used the shredder. If I'd only understood what he was trying to tell me...

 

[Combustix]

Ronmar thanks for advice bought used off cl. Had no instructions. I had run at 2000 rpm so I'm running slow. Will check clearances on blades and sharpen. I was able to download the jinma owners manual for the 6 inch model

 

[RoyJackson]

The guy at the shopping center told me he seldom used the shredder. If I'd only understood what he was trying to tell me...

I use my shredder frequently with no clogging problems. Of course, I don't have the blower (stuff falls below the chipper).
It does help to toss in some heavier twigs (up to about 1" diameter) to keep it cleared out.
As far as the blower chute clogging, most any chipper will with damp material. I do agree the shredder may aggravate that clogging.

 

[o2batsea]

Scary.

 

[Short Game]

...(stuff falls below the chipper).

That was my main issue with not having a blower. I made a 3PH device that would tow the trailer and also would hydraulically lift the trailer tongue from 12 to 62 inches off the ground. Great for dumping, but every load had to be scooped and shoveled into the bucket and loaded into the disconnected trailer. Then the trailer had to be re-hitched and hauled away. When I came back for the next load, I had to disconnect the trailer on a jack stand to load it and repeat the process.

That's why I decided to build the blower.

 

[Short Game]

o2batsea?

Scared of what?

I too liked my sea time.

 

[o2batsea]

Scary that junk like this gets to market and the buyer is stuck with an unusable pile. He has to reengineer the thing just so he can use it. Maybe more sad than scary.
A proper chipper shouldn't need an add on blower.

 

[RoyJackson]

Scary that junk like this gets to market and the buyer is stuck with an unusable pile. He has to reengineer the thing just so he can use it. Maybe more sad than scary.
A proper chipper shouldn't need an add on blower.

As I'd written in earlier posts, Bearcat makes a fine chipper and the model he has is a good unit for residential/small farm use. However, it isn't a commercial grade machine.
Short Game knew when he bought the chipper that the chips fell under it. Perhaps he should have bought one with a blower/chute.
As an owner of the same chipper/shredder (although mines was sold by Woods Equipment), I know what I'm writing about.

In fact, Short Game's post is the first one I've read of problems with the Bearcat chippers.

 

[Short Game]

In fact, Short Game's post is the first one I've read of problems with the Bearcat chippers.

Lucky me.

That problem of the chips in the reserve blade edges says a lot. Here are the details of what happened there, Roy. Since you have the same machine, and assuming you service your own blades, you should be able to understand this. You know the shallow reliefs that the four double edged blades bolt into? They are obviously ground or cut into the flywheel. The stone, or cutting head (I'm guessing it was a stone), had become rounded, so the cross-section of the relief, at the point where the reserve blade edge was to lay against the flat of the bottom of the relief, was ground into a quarter-round profile, not square. The reserve edge was lifted away from the flat. When they were tightened down, the hardened steel edges were simply snapped off. Somebody really dropped the ball on that for sure.

Then the misalignment of the drive pulleys was insult to injury, resulting in the premature failure of, and destruction of, both belts. All it took was a straightedge (and two new belts) to fix it, but that should have been right in the first place.

The cob job on making the blower impeller was so bad as to be unbelievable. Since I bought the impeller several months after the chipper/shredder, I have to think that eliminates the "bad day" hypothesis.

Hard to believe I got hit with all three of those and it wasn't the norm at Bearcat in 2003. $2300 bucks for the chipper/shredder, and $115 for the impeller in 2003, was a big bite for this old man. Then on top of that, the dealer treated me like crap for my troubles. That most likely sent me somewhere else when I bought my next tractor. So it goes. I now have a blue tractor, and not a green one.

 

[grsthegreat]

I find that if the blades and the cutting block on my Jimna are aligned with a dimes width between everything works great and the chips blow and pile as they are supposed to.

Nut over time if i don't maintain that spacing, i can get large chunks trying to jamb the works. As long as the spacing is maintained though, no problems.

I have seen someone in this site that has made a nice razor sharp feed roller for their Jimna that i wouldn't mind having......... looks like it would grab the smaller branches with ease, but my factory feed roller does pretty good.

 

[RoyJackson]

Lucky me.

That problem of the chips in the reserve blade edges says a lot. Here are the details of what happened there, Roy. Since you have the same machine, and assuming you service your own blades...

I pull the blades, but send them out for sharpening.

I am sorry to read about your problems though...

 

[Short Game]

I pull the blades, but send them out for sharpening.

Aren't sharp blades the cat's meow? What a difference they make.

I've been filing and grinding and sharpening stuff for 40 years. I ran into all the right old-timers when I left LA without a clue to come up to the Washington Coast. I had a natural talent for making things dull and then running them that way. The old guys had to get me turned around.

 

[RonMar]

I find that if the blades and the cutting block on my Jimna are aligned with a dimes width between everything works great and the chips blow and pile as they are supposed to.

Nut over time if i don't maintain that spacing, i can get large chunks trying to jamb the works. As long as the spacing is maintained though, no problems.

I have seen someone in this site that has made a nice razor sharp feed roller for their Jimna that i wouldn't mind having......... looks like it would grab the smaller branches with ease, but my factory feed roller does pretty good.

A dime by the way is about .045". I have heard the dime trick before, but when I measured one and found it measured at 45 thousandths, I opted for the feeler gauges. I set mine around .022". I guess set so a dime just won't fit would also be pretty close to 30 thousandths, but how much under .045" you get would be a guess... If you were working with large pieces or hard woods, a dime sized gap might really load up the rotor/cutters...

I welded some on my roller teeth and reground them sharper and that makes a big difference on how well it feeds and eats material.