I have a Grizzly 12 inch “portable ” thickness planer that I have been using for 12 years on relatively light duty. I just had the blades professionally sharpened and set them with a dial indicator so they should be within .002 of being parallel to the bed.
I find that since the you can’t feed a board more than 1/8 thicker than the knives are set for, and I usually like to take cuts around 1/16, I have to sneak up on a pre-set thickness in steps. As I get closer to the desired end point, if I’m left with less than 1/16 more than that end point, the board is not firmly engaged by the rollers and chatters. I therefore have to either get lucky so there is 1/16 greater than the final thickness, or I have to leave it 1/32 or 1/64 thicker than planned and hand plane after assembly. Should I expect to be able to shave 1/32 oe 1/64 inch off a board, on a planer like this?
Would I do better upgrading to a heavier duty 15 inch planer with steel rollers? (If so what woudl you recommend?
I have some 5/4 walnut I’m planing mostly to 7/8″.
Replies
I am not familiar with your planer,however on my ancient Powermatic 12 inch model,I can sneak up on any desired diminsion.
Work safely ¬¬¬¬¬¬¬¬PAT¬¬¬¬¬¬¬
Why not set the planer to multiples of 1/16" when you start. Take your lumber maximum thickness (say 1") and set the planer to that. Feed the lumber through and reset for 13/16" and then for your 7/8".
Hank, The unit never had a reliable system for setting the thickness numerically. It works on a sort of tape measure on a spring, whcih broke a year after I purchased it. I just know that one revolution of the handle is about 1/16inch.
I'm having some trouble following your description of the problem but I think I understand it.
First of all, you should be able to skim a hundredth of an inch off a board if that's what you need. Apparently the machine worked well before the knife change so I'd be suspicious of how the blades are set in the head.
A benchtop planer is designed to have the knives project a predetermined amount from the cutter head, if the knife projects more or less than this designed amount the planer won't perform properly. Typically the older benchtop planers, with knives that could be resharpened, came with a small cast metal jig that was used to set the proper knife projection.
The fact that you used a dial indicator instead of the factory supplied jig suggests that the knives are set at the wrong height, they are probably sticking out too far based on the symptoms you described. The knives are striking the wood before the feed rollers are coming down to the proper height to grab the stock.
The solution would be to find the factory supplied jig and reset the knives. If, after the knives are properly installed in the head, the machine doesn't cut evenly across the width of the board, that is corrected by unhooking the linkage between the two drive screws and advancing one of the screws slightly to even up the height and then reconnecting the linkage.
John W.
John,
I think you got it. I'm sure the the cutters must protrude slightly lower than the rollers, resulting in blade contact before roller contact. I can, through tedious trial and error, get the blades to protrude the same as each other, and to be parallel to the bed, but there is no way to know when they protrude the same as the rollers. I'll just have to back them off a little and try some test pieces. I assume you wouldn't want the knives to protrude downward any less than the rollers. Some imprecesion arises with this unit since the bed is sheet metal over a base. The sheet metal has a tendency to bow up toward the cutter slightly, but is pushed flat by wood as it passes. When measuring the height of the knives with a dial indicator, you have to actively push down to seat the sheet metal on the under-bed. I am still considering a heavier duty model, but am concerned about the corrugations of the steel rollers marring the surface. How big of an issue is this? Thanks.
Jay
Jay,
Thickness planer blades are never adjusted by measuring from the bed. The projection of the knives is set with a knife setting tool that was supposed to come with the machine. Except for disposable blade planers, I have never seen planer blades set any other way. On large planers the pressure bar, chip breaker and rollers are adjusted by measuring from the table but the knives are still set with a tool like the one described below.
The knife setting tool rests on the cylindrical surface of the cutter head and arches over the edge of the knife. The knife is adjusted to touch a reference surface on the inside face of the setting tool. As I said in my first response, if the cutting head isn't parallel to the table of the planer, that misalignment is corrected by adjusting the screws that move the head up and down.
You need to find the machines manual and the setting tool or get in touch with Grizzly, what you are trying to do with the dial indicator will never work and could damage the machine. I would also suggest that you read a book on machine tune up, winging it, the way you are doing, can get you in trouble.
John W.
did anyone think to check to see if the rollers are worn out. he may have set the blades to height specs, but the rollers are worn and do not grip the wood. my friend came to me with a problem with his delta. seems if he wanted 1/4 inch off a board he just cranked it down. the rollers just spun trying to push the wood through and wore out. needless to say, when the cost to repair to planner was added up it was cheaper to replace the unit, and he kept the old unit as a reminder to read and understand the instruction book.DUH. more money than brains I guess. LOL
I reset the knives with the little jig that comes with the planer, and slightly adjusted the parallelism to the bed. (This does work best with a dial indicator, attached to a little wooden t shaped platform.) THe issue does seem to have been that the knives were protruding too far and were contacing the wood before the rollers. The unit now works fine, although the measuring tape is useless, so I can't know exactly how much thickness is being removed in each pas until I measure with calipers.
Jay
And you've been setting your knives like this (too proud) for, did I read this correctly, twelve years? If not, what all the sudden possessed you to change what had been working for years?
I think that fortuitously, I had previously set the knives at the correct degree of protrusion (ie. at the level of the rollers) using the dial caliper. I have only had to sharpen the knives about 3 times in that period, whcih tells you how much I have used it.
JAYST,
I'm not familiar with your model planer, but I wonder if your problem isn't due to the relationship between the height of your newly sharpened blades and the feed rollers/chipbreaker. On my old planer, the rollers are adjustable, and are set by putting two strips of equal thickness on the outer edges of the table. Then crank the table up till the knives just brush the strips. The chipbreaker is then lowered till it just clears the stock, and locknuts tightened. Infeed and outfeed rollers are similar, but the adjusting nuts are backed off a specified amt after the rollers contact the strips, and locked down. Infeed is set to be lower than the outfeed. The stock is then held down even if you are only taking a skim cut.
Check your manual, and see if your machine is adjustable for this.
Regards,
Ray
Ray,
The set up you describe is common on the larger or older planers, but the benchtop machines are basically preset for the height difference between the cutterhead and the rollers. Nothing can be changed, so it is important that the knives be set at their designed height.
John W.
John,
Well, I was wondering about that when I wrote my last post. Too bad.
My planer IS an old one, I guess. It's a 12" Parks, that I bought new in 1974. I've pushed a pile of lumber thru that machine. The only trouble it's given me was when I let the cutterhead bearings go without lube too long and one of them siezed and scored the shaft.
Regards,
Ray
In this model, the cutter head raises and lowers and the bed is stationary. There does not seem to be a way to independently adjust the rollers. Thanks.
Jay
The problem is with the planer. You ought to be able to sneak up on your final thickness without any problems.
I think it's time for a new machine.
Do you trade in your car when it needs a brake job or spark plugs? Based on what was in the original posting there is no reason to think that the planer can't be made to run properly.
John W.
I keep vehicles for two years and trade. Most cars built these days don't need tune ups and brakes until 35K+ miles.
I wouldn't lose a bit of sleep upgrading a twelve year old benchtop planer that probably cost less than 200 bucks to begin with.
I'm a woodworker, not a fixer of disposable tools. I'm trying to get a mental picuture of dicking around with this out-of-date piece of equipment and just can't.
I'm also assuming the poster knows how to run his planer, change knives, and all that rot - especially after owning it for twelve years. No matter how lightly used.
We're not talking 20" Powermatic here friend. This is 12", 12 year old Grizzly. It ain't Old Charter. It doesn't get better with age.
Edited 6/28/2004 12:02 pm ET by cstanford
I have to sneak up on a pre-set thickness in steps.
That's the usual technique. Hog off most of the excess 1/16th at a time, then take very light cuts for the final passes. There is a very good reason for this, which Sgian Dubh explained to me recently on another thread. Basically, when taking deep cuts, the knives are compressing the wood fibers beneath the cut surface, and this will eventually telegraph though the finished surface unless the compressed part is subsequently planed or sanded off.
As I get closer to the desired end point, if I'm left with less than 1/16 more than that end point, the board is not firmly engaged by the rollers and chatters.
That indicates a problem with the machine. I suspect John W. is right and the knives are set too proud. The rollers should hold the stock firmly to the bed even if the knives are not even touching the wood.
Should I expect to be able to shave 1/32 oe 1/64 inch off a board, on a planer like this?
Absolutely! I routinely do 1/64th, or even less, finish cuts with my 12" BT. You don't need a bigger planer, especially not for a relatively soft wood like walnut, unless your boards are too wide for the 12" model.
"Everything should be made as simple as possible, but no simpler." A. Einstein
http://www.albionworks.net
CSTANFORD has a point. But if you like the machine I think that the others are right about the knife projection. You should be able to shave a 100 th off if you want.
Mike
If you do decide to look into a new planer, there are some recent improvements in some of the larger machines that bear checking out -- such as the digital depth of cut readout on the new Powermatic (Artisan line, which means imported). Also, be aware that the infeed rollers on some of the 15-inch planers are corrugated and will leave marks on the work surface if the depth of cut is too shallow. (You can get the rollers coated with neoprene which solves this problem.)
Can't you increase the tension on the infeed/outfeed rollers??
PlaneWood by Mike_in_Katy (maker of fine sawdust!)
PlaneWood
This is not adjustable.
I have the same planar and Grizzly states that the maximum depth of cut is 1/16". If you are cutting 1/8" at a time, then your knives are definitely set incorrectly (i.e., they are too proud).
I use a pair of planar pals to set my knives; the problem I have the most with the Grizzly 12" is the cheap (stamped steel) infeed and outfeed tables. They are always getting out of plane with the planar bed and after years of use, I find they are bent slightly in the middle. This leads to excessive snipe. I'm about to remove the tables altogether and replace them with longer ones made from MDF with either a laminate covering, or sealed with a couple coats of shellac and then waxed.
Good luck
Paul in Tinton Falls
PLaning resawn boards
What do people do to get a nice finish on resawn boards 1/16" thick? Table top planers only go to 1/8"?
Thanks!
JIM
hi jim,
you are aware that this is one of those mysterious, ancient threads....?
anyhow, one needs to deceive the planer to achieve what you want. place the thin piece you wish to plane on a thicker board that's about the same width and length, measure the two as one thickness, set the planer depth of cut accordingly and have at it.
eef
Getting to 1/16"th
Thanks so much eef! A simple solution.
JIM
I agree but then again I finish off most everything on my drum sander on each side...
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