question about converting MacKissic 12P tow behind chipper to 3pt

[JUSS10]

Little back story. Bought a 3pt chipper for my 85 B8200 HST but it was just too much for my little tractor to handle. Worked out ok as I sold it for what I bought it for. That said after using it the one time i knew it would be a useful tool to have around the property as we are pretty wooded and take down many branches every year that I'd rather not just turn in to a burn pile.

Do some research for a smaller chipper for my tractor I know I could spend almost $3000 for a new one that works with the lower HP I have but I'm not buying a chipper that cost half what I paid for my tractor. I found that MacKissic makes a version of their 12P chipper for 3PT and needs only 10-30hp and chips up to 3in branches. That's perfect for what I need and I found one for $100 only a few hours away. From what I can tell after talking to their support, the 3pt version is the exact same chipper they've been making for 40 plus years they just use a pulley setup to increase the PTO speed from 540 to 2400 at the chipper flywheel. I have all the parts and steel to weld up a frame to mount the chipper to and build the speed increase setup.

So here is my question. What's the better use of HP/RPM on my tractor? I have a two speed PTO so I can do 540 or 748. Am I better off using a 1 to 4.4 ratio with the 540 speed or a 1 to 3.2 ratio with the 748? Does it matter? Will one utilize the engine power better than the other? I know for resale, 540 would make more sense, that just means I need to find a larger drive pulley which will cost a bit more.

 

[twomany]

I've got the 3pt version (Largest MacKissic offers)

I run it off the 35hp tractor on the 1000 rpm pto at reduced engine speed for all work. That is plenty of power for that machine.

I run it off the high speed pto of the B7200 at about 2000 engine rpm for most stuff, especially leaves. When processing limbs too small for the wood stove but to big for the shredder, I run the Kubota at rated engine power and 540rpm pto

The chipper works VERY WELL at high speed! The shredder as well!

The factory speeder is a taper loc pulley pair with an idler/tensioner. The duplex V Belt costs about $100 but can be found for less.

 

[JUSS10]

I've got the 3pt version (Largest MacKissic offers)

I run it off the 35hp tractor on the 1000 rpm pto at reduced engine speed for all work. That is plenty of power for that machine.

I run it off the high speed pto of the B7200 at about 2000 engine rpm for most stuff, especially leaves. When processing limbs too small for the wood stove but to big for the shredder, I run the Kubota at rated engine power and 540rpm pto

The chipper works VERY WELL at high speed! The shredder as well!

The factory speeder is a taper loc pulley pair with an idler/tensioner. The duplex V Belt costs about $100 but can be found for less.

this is great to hear. Just got back from picking it up. It’s an older version but it’s solid and spins freely. Any chance you could measure the diameter of the pulleys? If the pulley on the flywheel is the right size I think I’ll just run a single belt like it has right now and just get the right size larger pulley.

 

[JUSS10]

also, how is the overload protection done on the 3 point version? belt slip? sheer pin?

 

[twomany]

The large pulley is 14 inch diameter. The small one is about 4 inch, but it's under a shield and out of sight.

Belt slip takes care of the jambs, but watch out for a clog in the chipper due to green tops etc. the belt will burn in less than the time it takes to get up on the tractor and release the pto drive.!

Ask me how I know......;-)

 

[GreensvilleJay]

I'd go 540. 'universal' so your other tractors could use it and as you said EASY to resell in the future. Cost of the larger pulley is minimal compared to 'other stuff' you may need to buy(steel,belts,pins, etc.)
Be nice if you can get a 'parts list picture' to see how they did it,saves you some R&D time.

 

[twomany]

The web site has the Illustrated parts list to view and download.

 

[Lencho]

Hi Jess10,
I have the 123-TPH and it is one of my most frequently used attachments.
MacKissick has great parts support so you can get anything you need to complete the conversion. I would convert to 540 so all stock parts and dimensions will apply.
That must be an old model as it has three holes to access the blade bolts rather than the hinged door I have. You are also missing the metal deflector on the output side. Easy to buy or make.
Let me know if you want photos or dimensions.

 

[Lencho]

Here are a few photos. In the first you can see the blade door and the chip deflector flap.

 

[JUSS10]

Thanks for the photos and help everyone.

Pretty sure this is a gen 1 model. That said, from what I can tell, very little has changed over the years. I did see the exploded diagrams on their site of the TPH123 so thats a huge help. confirms that it is indeed a 14" pulley. I can buy a 13.75" pulley and hub from surplus center for around $50 so not too bad.

Due to its age and the violent nature of such an attachment, I have it completely torn down. Bearings weren't in the best shape and I wanted to clean a few parts up. There are also a few cracks in the hopper that need repairs.

I have an uncle who is a machinist so he is making me a new knife out of tool steel (even the the existing one seems ok, I just need to sharpen it). the wear plate was cracked so he's making me one of those as well.

Going to wire brush, prime and paint old kubota orange to match my tractor. I have a large pile of 1.5" square tubing so the 3 point frame will be made from that. I have a PTO shaft with a 1" shaft attachment for the implement end and have a 1" keyed shaft and bearings laying around. Only thing I should have to buy is the bigger pulley and the right sized belt. Have plenty of idler pulley laying as well for the tensioner.

I MAY first rig it up to run on the front of one of my wheelhorse tractors (I'm a bit of a vintage garden tractor collector). MacKissic actually made a version of this chipper for the wheelhorse tractors. going to try it on one my 10hp tractors and see how it does till I can get the 3pt frame built.

My wife and I have our second child due in a week so I'm trying to get this all cleaned up and back together before then ha.

I'll make sure to create a detailed list for the conversion frame for 3pt once I get it done with a drawing for anyone else who want to do this. These older self powered models can be had for $100 and under if you keep an eye out. Add a few more parts and if you are good with a welder you could have a nice chipper for cheap.

 

[Lencho]

The hammer mill design of the shredder is great. I look forward to your completed project. Please post photos.

 

[JUSS10]

The hammer mill design of the shredder is great. I look forward to your completed project. Please post photos.

Will do! may ask you for a few pictures and measurements. I may want to add that door for the chipper knife. We'll see.

Just finished sharpening the old knife at work on a surface grinder. Should be good and sharp. Also ran and got some rubber washer for the hopper to hopefully prevent welds breaking on the hopper from vibration. I know they added vibration damping to the later models.

 

[Lencho]

The door is just a hinge welded to the side and secured with 2 machine screws. The opening is 2 3/4” by 4 1/4”.

 

[Lencho]

PS - congratulations on your new child!

 

[JUSS10]

PS - congratulations on your new child!

thanks! Not here yet but could be any day. technically not due for another week or so and I'd be ok with that. My in laws just had a massive honey locust come down in their front yard with the recent storms we had here in west michigan. Its like a giant bush. This chipper would be really useful for that. I actually got it back together today. rushed the paint job a little but it wasn't exactly in the greatest shape to begin with so paint would only get it so far anyway. New bearings, flipped the hammers around and will be putting in a new knife and wear plate that my uncle machined for me. All new hardware with grade 8 bolts and lock nuts.

As stated above, I think I will mount it to one of my vintage garden tractors first just to see how it runs. In the mean time I'll order the pulleys for the 3pt version and get that whole sub frame built up so I can just drop the chipper right on it.

 

[Lencho]

Looks great. Actually it looks very familiar- they really haven’t changed the size of the basic shredder at all between your version and mine.
I keep it on a small dolly to make attachment easy.

 

[JUSS10]

Thats smart! I need to get/make one of those screens you show. I'm assuming that screen will give the largest chips?

 

[twomany]

The door is just a hinge welded to the side and secured with 2 machine screws. The opening is 2 3/4” by 4 1/4”.

If I may add my 2 cents on that door.

Yes, It is possible to remove for service the two knives through the open door.

But you still need a propane of O/A torch to heat the c'sink screws up cherry red and a stout allen key on an extension T handle to loosen them. And you still should check and adjust the knife and anvil clearance. I just take off the entire chipper cover when it's time to go through the process.

Also, I've turned the hammers once to each new "corner". The last time they were out, I rowed them up in the mill and made a pass down the corners to leave an L notch. Effectively cutting out the rounded corner and replacing it with two sharp edges. Replacement hammers for some mills are shaped this way from the git go.

I used A400 plate to make replacement anvils. When I made one a few years back, I made 4. I sure hope I don't loose track of the other 3. ;-)

I do use the tool quite a bit.

 

[Lencho]

Juss10 - the bar screen is good for wet material. I switch to it if my 1” screen is clogging up.
Two many - I agree the blade door is small and heat is required to break the red loctite loose. I use a propane torch and a socket mount Allen wrench. That way I have lots of torque and don’t need as much heat. I hate to heat the blade up too much.

 

[Lencho]

Toomany- do you have the bigger model? Mine only has one knife.