How "Free" Should a Cutterhead Be?

[Mike Chalmers]

Installed a shelix cutterhead in my DeWalt DW735 planer. I have wrecked two belts (original and replacement) after very little use, say 25 bd ft. Looking for the cause. Pulleys appear to be coplaner. As far as I can tell, cutterhead is in the right location. Snap rings on either end pretty much guarantee that.
I have also noticed that the pulley and belt seem to get very hot quite quickly. I am wondering if maybe I have a bum bearing. Head can be rotated by hand quite easily, but does not spin easily enough to continue moving once I take my hands away from the cutterhead. Should it continue to spin for a bit, or is it normal for it to stop that quickly?

[Charles Taylor]

Getting very hot at speed is a clue that a bearing may be bad. For it to seem smooth when rotated by hand really doesn't tell you much, unfortunately. Nor does the fact that it stops pretty quickly. (Bearings with good grease don't take a long time to coast down from being spun; old, dried out ones do.)

If one end of the cutterhead gets much hotter than the other, I'd suspect the bearing.

[Rod Sheridan]

A lunchbox planer has a wound rotor motor, the brush friction will always cause the motor to appear not to coast like an induction motor will.

You may have a bad bearing, mis-aligned pulleys or a belt that's too tight.

Some helical heads can require more power than straight knife machines, are you trying to take as large a depth of cut as you did previously?

Regards, Rod.

[Joe Spear]

When I had a DeWalt 735, I replaced the original cutter head with a shelix. Soon after the drive belt broke. I had it replaced, and that one broke also. After a third one broke, I sold the planer cheap and got a different brand. There must have been some alignment problem, but I didn't bother to find out. The planer was really good with the original blades. If I had known what I know now, I would have just gotten carbide blades to replace the originals when they dulled.

[Mike Chalmers]

Thanks all for your comments. Pulleys appear to be coplaner. I am thinking belt too tight. It is one of the cheap Chinese knock offs, as opposed to a Chinese original. I have what I hope, is a genuine DeWalt belt on order. Will see if that makes a difference. Currently have another knock off on, and it seems to be working, but pulleys still getting hot. I also have my 20" CX20, so am not in a panic.
Also became aware that, even though I ordered the OEM size cutterhead, it is taking off 1/16" when gauge says 1/32". Pulleys still getting hot with reduced cut.
Another observation. Outside diameter of pulley where it is in contact with the belt, appears to get hotter much faster than the inside part.

[Mike Chalmers]

Problems appear to be solved.
Determined that the pulleys were misaligned by .01". Shimmed the cutterhead pulley. Put new "genuine DeWalt" belt on. Ran dedicated 20 amp circuit. Pulleys running much cooler. Machine is not stalling out and popping the breaker.

[Charles Taylor]

Glad you got it resolved. Thanks for reporting back and letting us know what the problem was.

[Lael Gordon]

Sorry to dig up an old thread — I am having the same problem that Mike was having with his DW735 planer and hoping he can answer a few questions for me.

After installing a Shelix on a new DW735 I noticed that the cutter head pulley was getting very hot. I replaced the bearings thinking that was an obvious fix but nope. Also replaced the belt with a new DeWalt OEM belt. After reading Mike’s post I checked and it does seem like the pulley gets hot on the outer diameter first.

I’m wondering, Mike, in what dimension your pulleys were “misaligned”, and how were you able to measure that. You also had mentioned that your pulleys were coplanar.

I put a straightedge across my pulleys and it seems that the drive pulley is about 0.050” farther out (away from the machine) than the cutter head pulley. However, I also have an old (and barely functional) DW735 with its original cutter head that someone gave me for parts, and the drive pulley is out by 0.035”. It does not get hot. So I’m not sure what “normal” is as far a alignment of the pulleys — or even if I’m doing a good job of measuring since there isn’t perfect access. Maybe I shim it by 0.015” so that it is the same as the old machine? Did your fix hold?

Any input from Mike or others would be appreciated.

Thanks!

[Chris Luke]

I think you need to be careful with the straight-edge approach. I believe the distance between the first groove and the face are not the same between these two pulleys (I've not measured it, it just seems that way) and it's hard to tell if you have 4 points registered given the confined space. I too have need to perform this alignment (Lux Cut III in my case), so I've ordered a couple of different pulley alignment tools that sit in the grooves, eliminating any differences in lateral geometry - no idea if there's enough room for these tools yet, but I'll give it a go!

Other minor observation, the edge of the aluminum pulley had a sharp corner with some small casting burrs that I rounded over with a file to reduce the chances of nicking the belt as I put it on. It also seems to me that there's a fair bit of lateral adjustment available between the cutter head bearings and the retaining clips. This means I should have room to tune it (with the persuasion device), but it also means it might move over time. I am wondering if the Lux Cut is perhaps a hair too short between the bearings.

[Lael Gordon]

Interesting! Please let me know if the alignment tools work and if so what you learn. I’ll keep fussing with mine...seems like it must be a pulley alignment problem — but its hard for me to imagine that being out of alignment by just 0.015” or so would create that much more friction. And if its more than that, like 0.050”, there might not be enough threads on the cutter head shaft to shim it out that much.