Advance Forest RDM Mulcher Review

[fishfactor]

We recently flew out to Idaho to see the RDM Mulcher from AFE in action. We have been considering adding a excavator for several months now and also tried a Fecon CEM 36 a while back. I won't do any productivity comparison between the two heads because the Fecon was on a yanmar SV100 and the AFE was on a CAT 315CL.

The crew at AFE was nice. It's a relatively small shop. We got to see heads being built and they are strong. There is a lot of 1" plate in these heads and they claim you can treat it like a bucket as far as durability.

The bearing box is a beast made mostly in house. Oil bath lubrication and no maintenance except for changing the oil every 1000 hours. They also run every one they build on the bench at full RPM for 40 hours monitoring the temp to make sure all tolerances and seals are correct. The output shaft is huge and uses a taper lock to hold the disc on.

The cutting/mulching disc has quadco teeth on the perimeter just like a feller buncher. The bottom has carbide bullet teeth and carbide chisel thumb nail teeth. The bullet teeth are the lowest and do the ground engagement. The top of the disk has quadco teeth with opposing quadco teeth mounted on the shroud and carbide chisel thumb nail teeth.

There isn't a grease fitting on the head, the only routine maintenance is teeth and the bearing oil.

The head is controlled by the pilot control on the foot pedal. You can cycle it on/off and adjust the power to the head easily. This machine had the tool control system which allows you to switch flow/psi to run different attachments with the push of a button. For the head, CAT had it at 65 GPM. The foot control is nice because when you are at full power, you loose a lot of power to other functions. You can quickly let off the pedal and boom up, then get back on the pedal. The disc has so much momentum you can mulch the whole time.

The technique for this head is completely different from a drum mulcher. For smaller trees up to 3" or so, you can cut them at the ground with the 10-11 o'clock portion of the disc at a lower RPM. The lower RPM allows the top quadco teeth to engage the material and suck it into the shroud. Then the opposing quadco teeth and carbide thumbnail teeth chip it up before it comes out at about 9 o'clock.

For larger trees I found it best to top them 10-15' up. Jon could get the mulcher to suck in the top of the tree like described above. Mine always fell for later mulching. Once topped, you simply use the disc like a saw to cut through the tree dropping down 1-2 feet each time depending on the diameter. The section above where you cut gets pulled into the shroud for reduction. You can also use the bottom of the disc to come straight down on the tree, but the carbides aren't nearly as fast as the quadco. You can also use just the edge of the disc and shave down the tree if you like, taking off 3" or so of the diameter each time. I just liked the first method the best.

For tops and other material on the ground, the most effective way is to feed them into the shroud on top of the disc between 9-11 o'clock. Once started, it will suck them in and discharge mulch.

If the material is flat on the ground, you can use the bottom of the disc to mulch it, or use the thumb to move it.

You can also use the mulcher to cut trees to harvest. Jon cut a 18" tree off at the base, then cut and mulched the top and limbs, then used the thumb to set the log aside.

Debris field is similar to any other mulcher with most discharge between 8-11 o'clock. Obviously, high in the air you get a wider range. You can reduce the distance and direction by keeping the disc rpm's down. If you need to cut something near a house or road, use low rpm's to cut the tree, then use the thumb to move it before mulching.

Overall we were impressed with the mulcher. The biggest factor for us is the versatility. You can mulch trees, cut trees to harvest, mulch the slash, and load them on the trailer with one attachment. You can even use the head to pull the stumps if needed. This is what made the decision easy for us.

There is a big learning curve as the technique is so different from a drum mulcher, but......

Our CAT 315CL with the RDM mulcher will be delivered in about 10 days

Here is a video.
http://www.youtube.com/watch?v=BRo86FXW950

[DIRTROAD]

AWESOME

I can't wait to see it. Congratulations!!

[cat 297c]

Congratulations!!! Next time i'm in NC mite stop by see it an your Gt run

[fishfactor]

Thanks guys. Come check it out anytime. Should be here the 2nd week in August. They are installing FOPS and some additional counterweight, then it should ship out middle of next week.

[Timark80]

That setup with the Cat 315 sounds like the ticket to handle most anything!

Did y'all demo or rule out the Kubota kx080 setup?

[fishfactor]

Not enough reach with the 80/100 class machines. Not enough weight in the back either. The 315 was the biggest we could go and be able to move without permit worries and needing a new trailer.

[WestshoreConstruction]

Good luck with the head, it looks like it does a decent job. But how do they get 65 gpm out of a 315 ? 65 Gpm @ 3000psi is 114 hp ? @ 4000 psi 170 hp. It really looks like it doesnt mind the head on there at all, the functions are still fairly quick.

[fishfactor]

Good luck with the head, it looks like it does a decent job. But how do they get 65 gpm out of a 315 ? 65 Gpm @ 3000psi is 114 hp ? @ 4000 psi 170 hp. It really looks like it doesnt mind the head on there at all, the functions are still fairly quick.

Total flow on the machine is 82 gpm between both pumps if I recall correctly. When they were tuning it they had it pushing 75 to the head at one point. I don't remember what psi they had it set to but I'll let you know when it gets here.

When you need use a function such as boom up you just let off the pedal a little, then get back on it. Since you can't mulch while moving up it's hard to notice. If you listen carefully in the video you can hear it.

The head actually mulches best when not at full rpm's. When you run the rpm's way up it just wants to cut and not mulch. Use it this way to fell large trees like a feller buncher, just no bunching or grapple ability.

To get it to run like this, you must have the optional computer tool control hydraulic system. It's a factory option and not many are ordered with it. We had our CAT dealer look and he couldn't find one in there inventory anywhere in the US. Without it, you loose about 30% of the flow.

It's going to be a nice addition to our fleet and will add more capabilities than just a mulcher.

[fishfactor]

Just looked up the specs and they show total flow at 79.2 gpm at 4980 max psi. Don't know how they get this out of 110hp.

[WestshoreConstruction]

It's not possible. That's my point. But I've been wrong before. The two pump flow from cat works ok but there is better set ups out there at a fraction of the cost. It may be that they theoretically have more hyd up than available but that is at zero restriction and as the pressure increases the flow decreases. Let us know how it goes.