Changing planer knives

[Ray Newman]

Colleagues: do believe it is time to change the knives on the 15” planer. Luckily, there is no taper width wise. But I have an upcoming project that may require the planer to be utilized more than before. And to say the least, I am a bit apprehensive about do it as seems that everything I hear is the job is a PITA.

Some claim that the jointer/planer knife jigs, like the one below really simplifies the task and shortens the time to do it -- https://www.infinitytools.com/planer-knife-setting-jigs

Has anyone utilized such jigs and how did they work or did not work out.

[Matt Day]

I’ve found the easiest way is using the stock knife setting gauge to get in the ballpark, and a dual gauge for getting, well, dialed in. The videos by Bob Vaughan are very helpful.

[Ray Newman]

Matt Day, the old GeeTech-Sunhill planer is missing its OEM (Original Equipment Manufacturer) knife setting gauge.

[Ron Selzer]

yes
it makes it easier
practice, practice and practice works best for this job





Colleagues: do believe it is time to change the knives on the 15” planer. Luckily, there is no taper width wise. But I have an upcoming project that may require the planer to be utilized more than before. And to say the least, I am a bit apprehensive about do it as seems that everything I hear is the job is a PITA.

Some claim that the jointer/planer knife jigs, like the one below really simplifies the task and shortens the time to do it -- https://www.infinitytools.com/planer-knife-setting-jigs

Has anyone utilized such jigs and how did they work or did not work out.

[Steve Jenkins]

You might look into Dispozablade. It’s a set that includes a self setting backer that their knives snap onto. The knives are double edged so it’s a simple matter of loosening the gib screws, pop the knife off the backer and put it back in the cutter head. I’ve had them on my 16” jointer for years and love them. No jack screws or springs. The backer indexes off the cutter head. I’ve found that the knives stay sharp longer than normal knives and since they are reversible the cost per knife isn’t a much more than two sharpenings.

[Robert Engel]

Yes, it can be a pain, for me it’s a 2-3 hour exercise. To be clear, it’s a 20” planer and getting knives set to within a thou across that distance is quite an exercise.

Jigs are fine -IF- the bed is absolutely parallel to the roller. I know this is not the case on mine. Close, but certainly not within a thou. I doubt this is true of any machine, and I can’t imagine the ordeal to achieve it.

So, I align the knives to the bed, which means setting up a dial indicator and working from underneath, which means lights, setup blocks to ensure consistent gauge location, removing infeed table - you get the picture.

My manual describes using a wood block and feeler gauges, but I can’t get consistent results.

[Mike Kreinhop]

I tried the knife setting jigs on my jointer/planer, and gave up after a couple of hours. They went into the trash.

My best success has been using a slightly modified version of the technique Bob Vaughan shows in this video:


https://www.youtube.com/watch?v=VRnrWOwun68

After I ensured my outfeed table was parallel to the cutter block, and the infeed table was coplanar with the outfeed table, I turned my attention to the blade installation. I removed the springs that push the blades up, as I didn't need them for my method. Rather than a random guess at the height when starting, I use two welder's right angle magnets to hold the blades in place while I gently snug the outside gib bolts just to hold the blades in place. Two sheets of printer paper between the outfeed table and magnets ensure the blades are uniformly proud of the outfeed table by a few thousandths for the final adjustment.

I follow Bob's method to set the blades at finished height even with the outfeed table. The last time I did this, setting the three blades took me about 20 minutes.

[Bruce Wrenn]

OP was asking about a planer, not jointer.

[Charlie Jones]

You might look into Dispozablade. It’s a set that includes a self setting backer that their knives snap onto. The knives are double edged so it’s a simple matter of loosening the gib screws, pop the knife off the backer and put it back in the cutter head. I’ve had them on my 16” jointer for years and love them. No jack screws or springs. The backer indexes off the cutter head. I’ve found that the knives stay sharp longer than normal knives and since they are reversible the cost per knife isn’t a much more than two sharpenings.

I love the Disposablades in my jointer. You can change them in 10 minutes. I plan to put them in my planer when the present blades are ready to be changed. It is a bit expensive the first time because you will need the blade holders. After that they are fairly cheap.

[Warren Lake]

tried a lesser knife setting gauge on the jointer that didnt have the fine adjustment that one has and didnt get it and had no patience for it, it wasnt even close. Disposa type knives have been slagged enough times on sites so while some are happy as many were not. I have a brand of them and took them out for high speed steel but would have to try them for some time to pass a judgement.

[Richard Coers]

"The only thing to fear is fear itself" You can buy an OEM gage at lots of places, that planer has been sold under lots of names. I've been changing stock blades for 48 years. No need for fancy jigs and rigs. Uniform tightening is critical to success. Lightly snug up all the bolts on the retainer first, starting in the middle. Then firmly snug the row up, then fully tighten them. Fully tightening on one end and working across will cause issues. Cleanliness is also important. After removing the blade, clean the head, the head slot, and clamp bar. You want zero residue on the surfaces. If you have any surface rust, scrape with a single edge razor blade and scrub with a Scotch-brite. Just go easily and methodically. It's not black magic!

[Warren Lake]

as well before fresh go in check if they were ground straightm then hone them with a hard arkansas slip stone. Be careful they will be wicked sharp at that point.

[Charlie Jones]

tried a lesser knife setting gauge on the jointer that didnt have the fine adjustment that one has and didnt get it and had no patience for it, it wasnt even close. Disposa type knives have been slagged enough times on sites so while some are happy as many were not. I have a brand of them and took them out for high speed steel but would have to try them for some time to pass a judgement.

Warren. Could you tell us where you read about people who were unhappy with the Disposablades? I am curious why.

[Warren Lake]

not sure I saved it but read it twice more likely three times. Will see if i did and likely from this site. the longer the knives the more unhappy. I save lots just dont always know where so likely have them in another folder but here is one.

451577

[Mike Kreinhop]

OP was asking about a planer, not jointer.

The OP has a planer, but he asked about the jig used to set the knives in a jointer/planer.

[Charlie Jones]

Hmm. One person unhappy. I wonder if he tightened the gibs correctly. I haven’t tried them in my planer yet but am eager to do so. They work great in the jointer. It cut about an hour off my changing time. On the planer I have had good success using the OEM knife setting gauge. The planer has jack screws.

[Mike Kees]

Best jig to set planer knives is the old style bridge type gauges with a dial indicator like Powermatic and others made for their industrial planers. I made one from a section of pipe and a indicator that I bought on ebay. If your head has jack screws you simply snug up the end screws just enough so the knife has a slight amount of "Tension" (it can still move with the jack screw). The knives need to be set SLIGHTLY LOW and then adjust with the indicator in place at each end. Recheck the knives and then tighten the gib screws working from the center out to the ends. It usually took me about 10 minutes per knife to do this to .001 tolerance.

[Ray Newman]

Colleagues: thanks for the information. Finally found the wrenches, knife jig, etc., for the planer. Re-read the manual which, indicated knives are spring loaded. Of course it does not indicate the direction to turn the screws to loosen or tighten.

Before I tackle this task, will start doing some stretching exercises in case need to adjust the rollers, chipbreaker, etc. Getting “at that age” where I am not as limber as I was.

Watched the Infinity Tools video about the jig I earlier referenced. Had some interesting tips and will purchase the jig to help setting the knives to their original height. Also apply penetrating oil to screws a day or so prior to help loosen things up.

Again, thanks.

[Robert Engel]

Ray before you do anything verify the cutter head roller is parallel to the bed, or using the jig won't work.

[David Stone (CT)]

. Disposa type knives have been slagged enough times on sites so while some are happy as many were not.

I switched my PM 100 planer to Self-Set Dispozablade/ESTA knives a couple years ago and really like them a lot. It takes 15 minutes or less to swap out a new set or edge and the accuracy is as good--or better, truthfully--than even the best results I ever achieved using a setting jig and dial indicator, which is to say something like a couple thou. It's turned what used to be an un-fun major PITA into easy peasy.

Before purchasing, I had the same experience as you in terms of being hesitant based on what (very, very little) user comment I could find. The system has been substantially redesigned at least once, and maybe twice, over the decades it's been offered and the negative commentary I found was largely old posts of someone saying they'd tried them years back and/or people arguing for considerably more expensive alternatives.

Dispozablade deserves more love and attention than it gets, IMO, as a worthy option for people happy with straight knives and simple machines but sick of spending time messing with jack screws and setting gauges.

[Warren Lake]

i have them just not used them. Ive seen unhappy people likely three times only posted the one. Ill try them sometime and measure and see what they can do. I do stuff as i learned and its still fine.

Is that accuracy they claim in the post accurate?