Underpowered Powermatic 15HH Planers

[Bill Reed]

A couple of us 15HH owners have been corresponding recently about maximum depth of cut on 14" wide pine boards. Our maximum depth of cut on wide boards is considerably less the 1/8" given in the planer's specifications. My full width cutting depth is less than 1/16" in soft pine. At larger cutting depths the machine stalls out and the motor trips. I haven't measured this cutting depth for hardwoods but assume it would be even less. This is often a problem for me planing rough boards that might have a slight taper from one end to the other. I get midway through the board and the machine stalls. I'm wondering if anyone is able to take a full width cut approaching 1/8" with this planer?

[Kyle Kraft]

Bill, is this planer the brother to the Jet 15" model?? If so, I have taken the max cut as defined by the little stopper doohickey at the top of the infeed side on a piece of 14" oak w/ no problems. She gets down and grunts, but it doesn't stall

[James Biddle]

I have the PM15HH and before that, the Jet 15". I haven't tried to take an 1/8" off a full width board and have no desire to do so. I can say that the biggest functional difference is the Byrd head on the PM. I suspect this is the root of the issue you describe. Although the Byrd head gives a much smoother cut, in my experience it takes more power to force the wood through the cutters. I'm basing this opinion on my experience when I converted my GI jointer from standard knives to a Byrd head. The amount of additional pressure needed to joint boards was noticable after the conversion.

[Joe Jensen]

Although the Byrd head gives a much smoother cut, in my experience it takes more power to force the wood through the cutters. I'm basing this opinion on my experience when I converted my GI jointer from standard knives to a Byrd head. The amount of additional pressure needed to joint boards was noticable after the conversion.

That's an interesting observation. I have a Byrd head on my Planer and I am trilled. I have been considering replacing the Terminus (Tersa clone) head in my 8" jointer with Byrd head. I read a few posts that said it was easier to face joint boards after the Byrd head. Wonder if they had dull straight knives...joe

[Bill Reed]

Bill, is this planer the brother to the Jet 15" model?? If so, I have taken the max cut as defined by the little stopper doohickey at the top of the infeed side on a piece of 14" oak w/ no problems. She gets down and grunts, but it doesn't stall

I don't know what the Jet planer looks like. Mine is the 3hp Powermatic 15" planer with the Byrd shelical head.

[Bill Reed]

I have the PM15HH and before that, the Jet 15". I haven't tried to take an 1/8" off a full width board and have no desire to do so. I can say that the biggest functional difference is the Byrd head on the PM. I suspect this is the root of the issue you describe. Although the Byrd head gives a much smoother cut, in my experience it takes more power to force the wood through the cutters. I'm basing this opinion on my experience when I converted my GI jointer from standard knives to a Byrd head. The amount of additional pressure needed to joint boards was noticable after the conversion.

I don't normally try to take such a deep cut either, but as I said in my post when planing rough lumber there is often enough variation in the thickness of the boards to stall the planer even when I start out trying to take a very modest cut. I think you are very probably right about the Byrd heads requiring more power. If so, Powermatic should have beefed up the motor on this machine.

[James Biddle]

I don't normally try to take such a deep cut either, but as I said in my post when planing rough lumber there is often enough variation in the thickness of the boards to stall the planer even when I start out trying to take a very modest cut. I think you are very probably right about the Byrd heads requiring more power. If so, Powermatic should have beefed up the motor on this machine.

Although I agree with what your premise, I find that its just so much easier to set your planer to the worst boards to start, plane them, and then just keep turning the handle by 1/2 rev per cut and run all of them through as fast as I can. Though, if you're running several hundreds of board feet through at a time, I can see you wanting the capacity. My projects generally only have a few hundred board feet at a time, so the multple passes don't bother me.

[Bob Feeser]

Coming from someone who has a Sears Contractor grade 12" benchtop planer, here is my take on planing. Their are vey little challenges when planing a board or two. For the professional planing multitudes of boards, and having a need to do so the most efficient way possible, what is the answer? I know you don't need me to tell you this, because we all face it every time we need to plane a large stack of boards. So onto the problem.
We use the jointer to face, or surface one side of the board, then take that newly flat side, and press it onto the jointer fence, and joint the edge. Now we have 2 surfaces, that are jointed to a perfected flatness, and even 90. Then we go over to the planer, and want to make the opposite side of the board, just as flat, and just as important, equi-distant in thickness throughout. (Then with the jointed edge against our table saw fence, we cut our final pieces to width, and use our miter set up to cut it to length) So back to the planing problem. Once we joint one side, we sometimes are dealing with stock that is a lot thicker in some areas, than in others. Knowing that we only have so much capacity to get through thick stock, we set our depth very lightly on the planer, to accomodate the odd board, that may have had a cup, or bow, or simply a saw mill error with a band saw, that made only a small section of it a lot thicker. Unfortunately, we have to run our entire pile through at this light setting. Then we tweak it again, and run the whole pile through again. The boring thing is that many of these boards, are coasting through without taking anything off of the surface, so the thick odd areas, are able to make it through the planer. Not only is the horsepower, and capacity of the planer come into play, the clearance from the planer bed, to the upper bar, or infeed rollers is a limitiation as well. The whole problem is further exaserbated by the fact that our planer can only handle one board at a time. Then along comes the answer.
Now I know this is expensive, but it clearly creates an understanding, as to what the solution is, and then we can reverse engineer our equipment in our heads, to realize what the problems are. Here it is

It's a Powermatic 201 planer. I am not saying it is the best planer on the market, or anything, but lets talk about how this machine, solves the problems. (It is interesting to note that some of the old Powermatic planers had one motor for the knives, and a separate motor to drive the infeed rollers) Anyhow the 201 comes with a 7.5 horsepower motor. The really interesting feature is that it sports Segmented infeed rollers with
sectional chip breaker which allows multiple piece planing and
consistent feed and finish. So what that means is that you can place multiple pieces of stock in this, at let's say somewhat of a varying thickness, and due to the segmented infeed rollers, they can be at different thicknesses. With the horsepower, I am sure it will not balk at the thicker sections of rough stock. The cutterhead is complete with four high speed steel knives and turns at 4,800 rpm producing 19,200 cuts per minute. With a maximum depth cut of 3/16 ths, you could pretty much set your first pass at a full 1/8th of an inch, based on your thickest spots, and pretty much expect to get a first time pass through, of an even edge on all of the pieces. Secondary passes could be reduced for the sake of smooth cuts without tear out. I could see a large outfeed table attached to the back of this thing, that would catch all of the pieces as they left, so you could be doing a lot of feeding, and not as much catching them as they left the back of the machine, especially with stock that isn't that long. With it's 22" wide planing capacity, you could make short order of a lot of planing.
Can I afford this monster at 4100 dollars discounted, or figure out a way to get its 1300 pound all cast iron construction down the steps to my basement? No, but it sure is nice to dream.

Plainng is one job, that is on the one hand exciting to do, to see a piece of rough saw stock, turn into something of finely grained beauty, but the job is no fun. If you have 20 boards, and have to run them all through 3 or 4 times, just to get down to beginning to make complete surface passes, just to begin to work on obtaining the thickness you need, a nice way to idle away your time is to be dreaming of the 201 making this job a lot easier. Ok, now let's see if we can work out the problems with the 15 inch planer. Wait a minute I am using a 12. Don't mind my jibber jabber, just a guy who likes to dream. For those with a forklift, those old PM machines are industrial grade monsters, but finding one of them that needs parts, can be very costly real quick.

When you think about the challenge a planer faces when having to chomp through a board that is 12, or 15 inches wide, and tyring to take a 1/8 th inch chunk out, compare that to a table saw, and how much it struggles to remove a 1/8 th inch wide slice out of a 2 inch thick board. I do not know if the 5 horse model is the solution. I would be curious to know, because at some point I need to upgrade my planer, and yours seems like a nice unit to have.

[Joe Spackle]

So Bob in a nutshell

It appears that Powermatic 15HH planer is underpowered for the capacities
listed on the technical spec sheet.

IOW When they released the 15HH unit they forgot to rewrite that part of the owners manual.

I rather suspected that the planer if used at it's rated capacity (1/8")
will not reliably function in attempts to plane 15" wide stock.

Byrd heads in my limited experience do take more power, the physics of the cutter head would demand that.
In essence you would have something like 15% (guesstimate on my part) more cutting edges engaged 100% of the time opposed to a standard three knife head that is engaging a knife only 1/3 of the time.
I suspect that we are going to start hearing more stories about how a particular machine is not working according to the specifications printed out for the machine.

Too bad R&D did nothing to see if the machine would perform as designed( redesigned) before they released it to the consumer.

It does not IMO speak well for WMH at this point.

Joe

[Tom Cowie]

Sorry Guy's

13 5/8 Red oak planed just fine. Not quite the full capacity and the maximum depth stop is set about a 1/32 less than the advertised 1/8 but it is close enough for me so I'm going against the grain on this one . I agree that the 7.5 hp is a much better planer but I needed mobility. I would question if the PM15HH would be considered a " work horse " machine . I bought mine for quality of cut not to hog off material so I never tried this test before. I'm glad I now know that the planer meets my expectations. The one thing that I found is that my 1.5 hp Jet DC
with a separator attached ,was gaging on the amount a chips this thing was throwing. To be fair I must admit that I stepped up from a lunchbox planer to this one so it is a big difference in the speed in which I can plane material but maybe not as fast as some are used too.

Tom

[Bill Reed]

Sorry Guy's

13 5/8 Red oak planed just fine. Not quite the full capacity and the maximum depth stop is set about a 1/32 less than the advertised 1/8 but it is close enough for me so I'm going against the grain on this one .

Tom

Tom, this is good news. You are the first owner of this machine I have found who can take nearly a 1/8" cut at full width. This give me hope that we can find out what is wrong with our machines. Maybe our cutterhead inserts are dull.

Thanks,
Bill

[Tom Cowie]

Hi Bill

I am really sorry to here about the issues that some are having with their planers. I don't normally take more than a 1/16 off when I run boards through mine. The motor did load more than usual but it never did try to stall. I probably won't make it a habit to plane at maximum depth , the surface finish was not as good. I noticed some tear out and the scallops as others have posted of.

Good luck with yours

Tom

[Bob Feeser]

Joe,
I appreciate the insight. I see what you mean about the increased constant contact with the head to the wood, as opposed to a three blade. I thought Powermatic had a 3 straight blade head 15" planer out not too long ago. The reason why I ask, is that I have the planer blade sharpening attachment for my sharpening station, that will only work with flat blades. I guess what you can say is that I am trying to make up for what the planer lacks in uumph with Tormek sharpened razor sharp blades. The thing that frustrates me is that all it takes is one little staple in the edge of a board, and there goes a nick in the blade, with the resulting ridge in the board. As much as I hate to admit it, I have the lumber wizard which works great, but don't use it as much as I should. After getting 10 negatives in a row, I skipped it on the next board, and sure enough, it's the one with a hidden staple, or nail edge, and nicks the blade. Is their any places that sharpen these new blade designs, or do you need to replace them?

So Bob in a nutshell

It appears that Powermatic 15HH planer is underpowered for the capacities
listed on the technical spec sheet.

IOW When they released the 15HH unit they forgot to rewrite that part of the owners manual.

I rather suspected that the planer if used at it's rated capacity (1/8")
will not reliably function in attempts to plane 15" wide stock.

Byrd heads in my limited experience do take more power, the physics of the cutter head would demand that.
In essence you would have something like 15% (guesstimate on my part) more cutting edges engaged 100% of the time opposed to a standard three knife head that is engaging a knife only 1/3 of the time.
I suspect that we are going to start hearing more stories about how a particular machine is not working according to the specifications printed out for the machine.

Too bad R&D did nothing to see if the machine would perform as designed( redesigned) before they released it to the consumer.

It does not IMO speak well for WMH at this point.

Joe

[Craig Thompson]

Bill,

I hate to ask about the basics... but, what kind of electrical supply? Appropriate guage extension / replacement cord?? I had the PM15 that I had put Byrd head on (aftermarket) and ran everythink from soft maple to purpleheart... never had an issue...

[Rod Sheridan]

I have experienced this problem on planers from 15" through 36" when the pressure bar isn't properly adjusted.

This normally happened when blades had been ground, resulting in a smaller cutting diameter.

Regards, Rod.