Hi, this is my first post on the forum after lurking a long time. I have a 3 year old DW735 that I bought new. I installed a Byrd helical cutter head a year and a half ago and it’s always worked well until this week. I have been planing 4/4 cherry (Nothing special) and taking light passes (1/32”) and the motor started to cut out. I know this is not an uncommon issue, but the odd thing here is that sometimes it trips the internal breaker but often it doesn’t. Sometimes it will sound like it’s bogging down before it cuts out, other times not. It has also cut out a number of times just as the load on the motor decreases (ie at the end of a board). It has also started to cut out, sounded like it was about to die, then roared back to life to finish the board. I am at a loss.
I have tried taking ever lighter passes but it’s still cutting out after every few passes with 1/64” or less cuts And seems to be getting worse.
This is what I have tried: I regularly clean the rollers with mineral spirits (did so again this morning), I waxed the bed, I checked for chip buildup in the out take as well as inside (I have it hooked up to a 2hp dust collector on a 4” direct line of only 10’), and I tried two different outlets. I also tried it on fast and slow speed and it’s the same result.
I called DEWALT but have been waiting for three hours now for a callback. I wondered if it was the breaker but as I say it only trips sometimes. If anyone has and suggestions I would really appreciate it.
Replies
It is quite new for this but have you checked the brushes ?
No I have not...does it sound like the brushes could be the issue? I have put a few thousand BF through it, all hardwood...
I'd bet on brushes
Great thanks so much! I have ordered a set. Are they hard to install? Will I have damaged the motor by running it with bad brushes?
You should be fine. If you can access the covers for the brushes, it's an easy job. There is sometimes a short break in period for the new brushes to make their best fit once they are installed.
While I am not familiar with that particular machine, brushes can certainly cause intermittent operation of any motor if they are not making solid contact with armature. Usually caused by wear, this erratic operation could also be caused by dust build up if the motor is not properly sealed.
What gives me pause is your statement that at times the motors internal thermal breaker is tripping. I don't see this as being caused by failing brushes since if the brushes don't make contact no electricity flows hence no heat or current. Also you make it sound like it's only a problem during operation under load. Worn brushes should cause erratic operation at all times. Your symptoms could be the result of a failing bearing somewhere in the motor or machine itself this could result in thermal overload and trip the internal breaker and could also cause the other symptoms you described.
I hope for your sake it is the brushes, since they are usually easy to replace and in a known location. A bearing problem may be much more difficult to isolate and could be non-serviceable since it could be internal in the motor, in the cutterhead, or anywhere else in the drive system of your particular machine.
Another potential source of the problem would be any gears in the drive system if any, again I don't know your machine, but if it has a gear drive system for the rollers or cutterhead and they aren't meshing cleanly they may also produce similar symptoms as they intermittently bind and release.
A possible diagnostic test could be to place a clamp-on Amp meter around the power cord. If the brushes are failing I would expect to see intermittent drops in the amperage, if it's a bearing or gear problem I would expect to see spikes in the amperage as the load increased. Just my theory
If the problem does only appear when actually planing wood I might start with the bearings in the planer itself since it seems to me they would be under the most load then, while the bearings in the motor would be under a more constant load anytime the machine is on not just in operation.
Good Luck
Maybe post again when you find the solution.
Depending on how long its been in use, the Shelix cutters may need to be rotated since they tend to get dull after a while. Dull cutters can add a tremendous load to the overall performance. I've noticed that since the Shelix was installed the load on the motor is greater than when it was blade only. My guess is that its due to the constant contact the cutters make vs. the blades giving the motor a rest between cuts. The motor wasn't designed to perform under these conditions. In the 8 years that the 735 was used before the Shelix was installed it never tripped an overload breaker. That's even with dull blades. But since installing the Shelix the load seems to be greater and will occasionally trip an overload breaker. Even on lighter cuts. It seems to happen more frequently on the faster feed speed. Good luck. Sometimes an upgrade isn't. Just trading one problem for another.
" user-6898725 | Great thanks so much! I have ordered a set. Are they hard to install? Will I have damaged the motor by running it with bad brushes?"
They are easy to change. The caps sometimes have a screwdriver slot and are made of plastic so a little finesse is in order. The brushes get ground to the curve of the commutator. This causes a little noisier operation and a few sparks during the first few seconds of operation; don't let that freak you out, it's ok.
Brushes exhibit behavior problems well before any damage may occur in my experience.
Thanks everyone again. Another question: I went to look at the brushes today while waiting on my order and Found that the screw holding the cover on the port over the belt was loose...like loose enough that the cover basically fell off. I know the dw735 has an autoshutoff if the top cover is off, but is the shutoff connected to the ports as well? Wondering if under load It might jiggle it enough to open up and trip the shutoff...
And one more question...how often do you rotate your cutters on the helical cutterhead? I did mine probably eight months ago and have run many multiple passes on around 200-400 bf since then...
Ok so after my daughter went to bed I tried it out again. It was obviously not the side panel. I took the brushes out and they both looked ok, no obvious carbon deposits or anything. I also ran it until it cut out and the. Immediately opened the case and tried moving the cutterhead manually. It moved like it should and With the same resistance as when cold. The Outside of the cutterhead bearings were Also cool to the touch. No sound or “feel” like grinding bearings when I turned it manually. The rollers have a bit of a clunky feel to them but they turn pretty easily although they do make a bit of a noise...I think though they have always been like that. I will try new brushes when they come in next week but I am starting to think it’s something else. Any other ideas? Am I missing something on how to check
The bearings? Still no call back from DeWalt either...again I really appreciate the help
I've had issues like yours when chips clog the internal plastic exhaust shroud. Jammed chips are not apparent unless I completely remove the shroud and carefully examine it. Sometimes it may require raps with a mallet to loosen the chips from the narrow throat. If the throat is not completely clear, the lugging will continue. More common with soft woods but can occur with hardwood, depending on moisture content. Lightly spraying silicone inside the shroud may help, but is not a cure all.
If the cover holding the brush in place "fell off," yeah, thats a big problem. The motor wont run if the brushes aren't in correct contact.
I would be extremely cautious about spraying silicone anywhere in my shop. It is a leading cause of finishing problems such as fisheye and even the smallest amount can be problematic if it gets on your work piece.
Insert rotation for me is around 18 months and I use the machines nearly every day. These are larger machines but, this will give you an idea.
The fact that the brushes look good makes me turn away from that being the cause. They are inexpensive and changing them will still eliminate that as a possibility.
The fact that it 'bogs down' and then comes back to life certainly steers us toward some moving part that is not moving well that eventually puts enough load on the motor to make him stop.
Since you have gone with the insert head you are financially committed to the machine to some extent. Unfortunately this comes at a time in our history when people who repair small machines have been pretty much erased from the landscape.
Does anyone on here know of a resource for user-6898725? I am pretty handy but, the idea of tearing down a lunchbox planer and rebuilding it does not sound fun. The financial commitment already made makes putting the time and effort into it make sense.
If you go after it I would research as much as I could before I begin. You Tube, articles, forums where folks have rebuilt DW735's. I did a search on 'rebuild a DW735' and got hundreds of videos. They are on bits and pieces but, all should be somewhat educational.
I would also have the time and place to work on such a thing reserved. Folks around my digs know to NOT come a knocking when I am in the shop. In appreciation I poke my head out at regular intervals or when promised ;-)
I have the 733, a close cousin of the 735. I had issues when the belt started going. Its worth inspecting, just to make sure.
The fact that your brush cover fell right off is still disconcerting.
RE: Rotating cutters. You need to inspect the finished product to make that determination. If you notice tear-out or burnishing then it's time to rotate the cutter. The issue for the 735 comes down to the fact that the motor wasn't designed for using a constant contact cutting process that the Shelix creates. While it may not seem significant, the use of blades does give the motor a rest between knife blade contact and it's enough to make a difference on the motor load and amperage demand. The cutout breaker is doing it's job since the motor is overloading. Like I said in the previous message. In eight years I never had an issue until I installed the Shelix cutter. It's not that the Shelix cutter is the problem, it's that the motor and electronics weren't designed for this type of load. Therefore the motor protection circuits are reacting properly. I'm thinking of going back to the blades. Actually the final finish cuts were much better with the blades. Good luck to you.
Thanks to everyone. RevBob: I understand that the draw on the motor is greater with the shelix but lots of people have installed it without major issues over the last few years. It may reduce the life of the motor but should not kill
It after eighteen months...especially as I usually take a light cut. The noise reduction is well worth it though imho.
After I try the brushes and a new breaker, if that does not work I will take it into the local dewalt service shop. When I find out what is wrong I will post again in case someone else has a similar problem.
An update: changed the brushes and no luck. I took it to a DeWalt authorized service dealer and they said the magnetic field was unstable so it needs a new armature and What DeWalt calls a field. Both parts are crazy expensive and on back order so I will likely opt for a new planer. Not sure if I will try the Byrd cutter again or leave it stock at this point...
EParts has the field (~$70) and the armature (~$190 outrageous) in stock. Combined the better part of the cost of a new planer. I would keep the Shelix, eBay the remains (hopefully you kept the original 3-knife head), and buy a new DW735. I have Shelix heads in all my 4-post planer and 8-inch jointer. I’ve processed many BF of birch, white oak, and cherry. I’ve only rotated cutters after snagging an imbedded rock. According to Holbren Shelix cutters are long lead time. I am waiting 6 weeks already to outfit my DW735 in my away shop. The Shelix head is a valuable item.
“Unstable magnetic field” is an interesting turn of phrase. Field windings are pretty dumb, they either have continuity or they don’t. The armature with the commutator is more suspect. New brushes are a start, but if the commutator is fouled or worn it may need some refreshing. In my experience service centers (and car shops) are more inclined to replace rather than find the root cause.
Before I install (if I ever receive it) my new Shelix head I will make a study of 3-knife vs segmented cutter loads.
Best of luck, cheers, and stay safe. —Dean
Oh dear. I was going to suggest testing the capacitor. You might be better with a new motor (which is an easy fix) rather than motor parts (which may cost more than the motor as a unit and are really fiddly to fit)
This article is for HVAC systems but applies to other motors too:
https://www.achrnews.com/articles/135163-testing-the-run-capacitor-while-the-system-is-running
I had a tool with a dead spot on the armature. I could rotate the shaft by hand and it would run normally again for a while.
Lots of things, sadly, aren't worth the cost of repairs these days.
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