DR 16.50 PRO Chipper Issues

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JoeGrow

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Hello all,

I recently purchased a used DR 16.5 Pro chipper with 36 hours on it. It seemed to be well kept, and the knife had little wear on it, however I sharpened it keeping its 40 angle using a belt sander. I also squared off the wear plate which also didn't seem to be showing much wear and adjusted it to it's 1/16" gap. I did a service on the machine, and fired it up without any issue whatsoever. The issue I'm having is that although this machine seems capable, it does not even remotely self feed even the smallest of branches. Branches approximately 1/2" will be eaten by the machine without much resistance at all, but requires me to manually feed it. A 2" branch can be fed into the machine with pretty substantial resistance, but not as if the clutch is slipping. It tends to "hammer" my hands with branches over 2" and requires serious self feeding, until what's left is too far down to safely put my hands into the hopper at which point is just bounces around the hopper. The manual for the machine shows that by sharpening the knife and or adjusting the wear plate, my issues would be mitigated. For what it's worth, there seems to be no issue with the engine running at the proper RPM. This seems to be the issue whether I'm using fresh cut limbs or dried out branches. Also worth mentioning is that the fresh cut branches seem to put out a stringy shred, where dry matter produces chips. It's not producing any fine saw dust. I've tried adjusting the wear plate at it's recommended distance, and also brought it further out and closer in with no real difference in results.

I purchased this secondhand thinking by spending a bit more than what a smaller big box store machine would cost, I would get a more capable machine however judging by some of the videos and online reviews of even the Harbor Freight wood chipper this thing is not what I imagined it to be. Am I expecting too much of the machine or is there something I'm missing? Is it worthwhile to buy a new knife kit and wear plate on the chance that it is improperly sharpened/adjusted?
 

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Move the knife edge out a bit more
Would you mind explaining what you mean a little more? The knife on my machine is in a fixed position, and as I stated I adjusted the wear plate probably from as close to 1/32" to the knife blade as far out as 3/16" with little impact on my issue. Thanks!
 
Would you mind explaining what you mean a little more? The knife on my machine is in a fixed position, and as I stated I adjusted the wear plate probably from as close to 1/32" to the knife blade as far out as 3/16" with little impact on my issue. Thanks!
That's what I think he meant, a closer gap, maybe you can sharpen the knives or cutting plate.
 
That's what I think he meant, a closer gap, maybe you can sharpen the knives or cutting plate.
I did try to sharpen trhe knife and square off the cutting plate with a belt sander keeping the 40 degree angle on the knife true, but truthfully I'm not sure how sharp the cutting edge really should be. I wonder if a new knife and wear plate would mitigate the issue I'm having, or am I simply expecting too much from the machine?
 
It is very important that the sharpened surface of the blade is extremely flat.

A belt sander may be rounding off the edge of the blade ever so slightly.

Maybe get a new blade and see how it works. If a new one works then you know your sharpening is the culprit.

The very small tip of the blade is what pulls material in.

That's a tiny chipper for those of us in the biz.
 
Stringy chips and not self feeding both indicate dull knives.

I learned a lot from this video:

I modify his procedure by putting engineers blue on the beveled face of the knife. That way I can see if I hit the whole face. I rotate my knives before they're dull (I'm a landowner not commercial) and it takes multiple passes to get them sharp. After a couple home sharpenings I'll have them ground so the angle is trued up.
 
It is very important that the sharpened surface of the blade is extremely flat.

A belt sander may be rounding off the edge of the blade ever so slightly.

Maybe get a new blade and see how it works. If a new one works then you know your sharpening is the culprit.

The very small tip of the blade is what pulls material in.

That's a tiny chipper for those of us in the biz.
I suspect you might be right. Understandable that this is a small chipper for commercial purposes, this is namely for residential clean up. I went ahead and ordered a new blade, the correct gap-gauge, and wear plate hopefully that will solve my issues. I suppose my main question is seeking confirmation that the chipper's performance is not normal, and that it should not require such great effort to chip smaller (~2") diameter limbs.
 
Stringy chips and not self feeding both indicate dull knives.

I learned a lot from this video:

I modify his procedure by putting engineers blue on the beveled face of the knife. That way I can see if I hit the whole face. I rotate my knives before they're dull (I'm a landowner not commercial) and it takes multiple passes to get them sharp. After a couple home sharpenings I'll have them ground so the angle is trued up.

Thank you for the confirmation and sharing the video. This is an awesome resource. I'll give it a go!
 
For what it’s worth, I replaced the blade with a new OEM one and a new wear plate and all of my issues were resolved. It now makes quick work of 2-3” branches and self feeds. I will keep the old blade have it sharpened this way I’ll always have a sharp blade on hand. Thank you for all of the input!
 
For what it’s worth, I replaced the blade with a new OEM one and a new wear plate and all of my issues were resolved. It now makes quick work of 2-3” branches and self feeds. I will keep the old blade have it sharpened this way I’ll always have a sharp blade on hand. Thank you for all of the input!

Get the old blade sharpened soon and give it a try.

Now you have a standard and it's good to have a factory standard around.

You may need to take it to your sharpener to show them what it's supposed to look like.

Take good photos and save them of your new and old blade and wear plate. On larger chippers the wear plate is called is sometimes called an anvil or bed knife.
 
I have a similarly small chipper (Janzen 1500) which works well for my small scale use. I sharpen the blades by holding them in a vice and using a flat file. I find the file helps me maintain the appropriate angle by keeping the file flat against the blade. I file towards the cutting edge, not away from it. Wear gloves!

Howard
 
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