Replacing circuit breaker on Dewalt 735

ear3

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I've started to have real issues with the breaker on my 735 tripping when under load.  It only happens when I'm running wider boards (>8"), but I'm not running the machine past it's capabilities in my opinion.  We're talking 1/64th passes on the slowest speed with a Shelix cutterhead installed, and when it trips, theres no sound of serious strain that I can discern that would indicate I'm pushing the motor too hard.  And given that the problem is a recent development, and has gotten worse over time, I don't know what else to attribute it to (interior is clean, and I keep the bed waxed).  The breaker also takes forever to reset, which I've heard is another sign the part might be failing.

It looks like it is a relatively easy install, so I've ordered up a new breaker.  There's a video on installing the part, but it's for the 734 -- so my question for those of you who have done this is whether it's basically the same process for the 735?


 
Do you have access to any electrical tools to see what’s going on?  I’d look for a voltage drop on the circuit when the tool is under load and check the amperage draw into the machine to see if it’s exceeding the rated draw.  You very well could be right, but if it’s easy to get those numbers, it might confirm it.

And sorry, I don’t know anything about the teardown on a 735.  I did see in the manual that there is a 2 minute delay on the onboard breaker before it can be reset.  I’m assuming the delay you mentioned is longer than that?
 
It could be the breaker but it could also be another issue in the supply of voltage to the motor, a loose connection, faulty switch or other issue causing a voltage drop at the motor resulting in a higher current draw.  The Shelix head will increase current draw over a SHARP set of straight knives by a bit under 10%.  I have had a Shelix on my 735 for about 5 years with no problems related to tripping the overload.
 
Purely conjecture on my part Edward, however if your mains breaker isn’t cutting out and it’s always the breaker on the Dewalt, I’d scrutinize the Dewalt breaker first. Breakers and GFCI’s are a pretty temperamental lot. I love 💕 breakers yet I hate breakers. They all “wear out” at some time.

I have the same setup and if you did the change over to the Shelix cutter, I’m confident you’ll be able to easily swap out breakers.
 
I don't -- electricity in many ways remains a mystery to me.  But I'll look into it and see if I can run some tests.  In any case, replacement 735 breaker is less than $20, so no harm if this turns out not to be the ultimate cause.

When I first got the planer, I did trip the mains breaker a couple of times, but that was with the stock cutterhead and what turned out to be rapidly dulling knives.  Since I installed the Shelix, I haven't once had an issue inside the house, and it's only recently that the breaker on the machine has started to give me issues.

RKA said:
Do you have access to any electrical tools to see what’s going on?  I’d look for a voltage drop on the circuit when the tool is under load and check the amperage draw into the machine to see if it’s exceeding the rated draw.  You very well could be right, but if it’s easy to get those numbers, it might confirm it.

And sorry, I don’t know anything about the teardown on a 735.  I did see in the manual that there is a 2 minute delay on the onboard breaker before it can be reset.  I’m assuming the delay you mentioned is longer than that?
 
When I swapped my 20" planer out for a Shelix head I thought the motor worked harder. More than once it would kick the breaker but never had before the Shelix install.

It would be interesting to check amp draw on a board say 8" wide with a 1/32" cut before and after the Shelix install.
 
I have had the Shelix on my 735 for a long time. I can't take as deep a bite in a pass as I could with the factory cutters. The design of the Shelix means there are always knives cutting wood throughout the rotation of the head. Seems to me the motor necessarily is working a bit harder with the Shelix than the old head. Never tripped breaker with mine though.

Jack
 
The carbide inserts are probably dull and the tables need waxing, rotate them, wax the tables and your problem should go away. On a low level, low hp machine like the DW it will give you the problem you describe. The machine wasn't designed for the load an insert cutterhead puts on the motor.
 
That was the first things I checked off the list -- inserts were just recently rotated when the problem started, and I always wax.  I'll report back how it does once I've installed the new breaker. 

kcufstoidi said:
The carbide inserts are probably dull and the tables need waxing, rotate them, wax the tables and your problem should go away. On a low level, low hp machine like the DW it will give you the problem you describe. The machine wasn't designed for the load an insert cutterhead puts on the motor.
 
It turned out to be a simple job replacing the breaker.  It's a little difficult to access through the on-off switch hole, like one can apparently do on the 734, so I took off the front cover, which involved 6 screws plus 3 for the depth gauge plate:

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Haven't tried any wide boards yet, just a few narrow ones to ensure that the machine still worked after putting it back together.  I'll try to run some tests soon and see if a new breaker makes the difference.
 

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Just an update -- I haven't maxed out the Planer yet since replacing the breaker, but I did just run a bunch of 9" wide 8/4 walnut.  Prior to breaker replacement, stock this wide (and generally, anything over 8"), was causing the breaker to trip even on a pass limited to 1/64 depth of cut (equivalent to a quarter turn of the depth wheel), and at the slowest speed setting of 1.  Did not experience any problems, so I am hopeful that the breaker was indeed the culprit, and that the issue is now resolved.
 
Good news! Sounds to me like you've solved your problem. 

I've owned a 735 for several years and have never had any breaker issues whatsoever.  Hopefully that will continue to be the case.
 
ear3 said:
Just an update -- I haven't maxed out the Planer yet since replacing the breaker, but I did just run a bunch of 9" wide 8/4 walnut.  Prior to breaker replacement, stock this wide (and generally, anything over 8"), was causing the breaker to trip even on a pass limited to 1/64 depth of cut (equivalent to a quarter turn of the depth wheel), and at the slowest speed setting of 1.  Did not experience any problems, so I am hopeful that the breaker was indeed the culprit, and that the issue is now resolved.

I had the same issue with my planer after switching to the byrd head. I fixed it the same way as you did. Cheers!
 
I had the same issue with my planer after switching to the byrd head. I fixed it the same way as you did. Cheers!
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So just to continue this one step further, is this a chicken or the egg situation. No breaker problem before the switch? The head was switched to a Byrd unit which is known to put on more load. Did the problem start shortly after the install or after the inserts started to dull to point of further overload? Have you had to rotate the inserts since you replaced the breaker?
 
Correct, this only started to manifest once I switched over to the Shelix, though it took a while, and was not an immediate thing.  I'm almost certain it's not a dulling cutter issue though, as it was happening both before and after I last rotated them.  Or maybe the strain put on the breaker by dulled cutters crossed some sort of threshold that couldn't be uncrossed even after the cutters were reset?  Not conversant enough with electrical stuff to know if that's even a thing.

kcufstoidi said:
I had the same issue with my planer after switching to the byrd head. I fixed it the same way as you did. Cheers!

So just to continue this one step further, is this a chicken or the egg situation. No breaker problem before the switch? The head was switched to a Byrd unit which is known to put on more load. Did the problem start shortly after the install or after the inserts started to dull to point of further overload? Have you had to rotate the inserts since you replaced the breaker?
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Breakers can become more sensitive with repeated overloads, its also interesting that they install an over rated breaker at 18 amps. Those cutters perched the way they are on the Byrd heads will have a tendency to dull the main face of the insert along with some secondary dulling of the 2 exposed sides as part of the cutting action. This will tend to lessen the life span of those 2 sides with the only truly sharp side being the opposite cutting edge that's protected. This dulling action will put more load on. It will be interesting to see if the breaker pops as the cutters dull and how long the replacement breaker lasts. I really hope it doesn't create to much aggravation.
I had one of those planers back in 2006/2007 and upgraded to Hammer A3-31 for 2900.00 CDN, I made the payments just by not having to replace the low quality knives, the Shellix head was not available.
 
The Shelix head on my DW735 increased current draw on a 10" wide hard maple by 9% over the sharp stock blades the Shelix replaced.  I would expect that with usage the Shelix head would stay at a relatively steady draw while stock blades would increase current draw as the blades dulled.  I've had my Shelix head in for about 5 years with extended usage planning hard maple, white oak and lots of Ipe.  I've not rotated the inserts except a couple that were chipped and I don't notice any loss in surface finish.  With my heavy hobbyist workload I would expect a set of inserts to last many decades.
 
After years of hobby use why don't you check the current draw again and confirm your thoughts.
Unfortunately years of use doesn't really quantify into anything. I'm in a slightly different category as I do this daily and I've run my 20" Helixhead from Hermance for 15 months and run approx. 15,000 to 18,000 BD.FT. Everything from century old Douglas Fir, Ironwood, Hickory to sandfilled Exotics and just recently had to rotate the cutters because I couldn't plane any more then a 1/16" per pass on a 12" board without overload dropping the motor circuit. There was no real change in the appearance of the cut and at first glance the cutters didn't seem dull. After rotation the machine was noticeably quieter and could easily plane an 1/8" plus again on wider boards. That's one of the issues with carbide inserts they become dull sharp.
 
Another variable is since this is a cord-powered machine as opposed to direct wired what is (if any) the length of the cord used with the machine. I understand we are talking about the breaker in the machine as opposed to the breaker panel but voltage drop at the machine can cause an increase in current.

So for example my DW735 is in my garage shop. It's about 30 feet from the main panel to the sub-panel in the garage, then another 60 feet to the outlet where the DW735 is plugged in. I don't use an extension cord so I have a run of ~90 feet of #12 wire. Every installation will be different is my point, and it's not just the machine that can affect the breaker trip.
 
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