parks planer knives

[tim weidman]

hello everyone. bought a 12" parks planer lasr year from a retired contractor. have had great luck with it. checked the knives when i got it and all were in good shape and straight. have been planing some oak i had sawn fron some large posts a few yrs ago when i hit the dreaded "nail i missed" :eek:!! now the blades are chipped and need replacement. i have a download of a parks manual but it is a little vague. so here are a few questions for the more experienced. #1 i started loosening the 5 large allen screws and ended up having to use a 2 ft bar on my allen wrench. should they be that tight? i wouldn't think so. am soaking remaining screws with a penetrating oil in hopes they will loosen easier. #2 after loosening the 5 screws to the first knife i seem to be having trouble getting the knife out. am i missing something? from the manual it looks as if it is only the 5 screws then the knife and backer piece should pop rite out. but it seems to be stuck. almost didn't get my screw driver out from under knife! any help would be greatly appreciated. thanks tim

[Matt Meiser]

Photos would be helpful but if yours is "newer" and has the jack screws--are you sure that's not what you turned? You should be able to back the ones that lock the knives way out and you should be able to get them loose enough that the knives would fall out if you turned the head around down.

[tim weidman]

matt i believeit is mid 80's vintage. digital camera crapped out and no funds to replace so no pics. yes it does have the jack screws and i tried screwing them out but met ALOT of resistance. blades did not budge. didn't want to strip those smaller screws considering the problems loosening the bigger ones. i have sprayed everything with penetrating oil and will do that every day for a few days to see if anything loosens up. having never done this on this particular machine i thought i would ask some experts. changed knives on my old delta portable with no problem. knives dropped out with no effort. will have to see if anything loosens up. thanks for the reply.

[Matt Meiser]

You might tap on the knives with a small block of wood and a hammer and see if they are stuck in place with rust, sap, whatever. Put the block against the face of the knife and tap towards the locking screws. At least that's what I'd try next.

[Jon Kasmire]

I have the same planer, and having recently replaced the knives, I have a guess as to the issue.

They probably aren't original Parks knives. The replacements I have spec to 1/8 x7/8x12. The problem here is that the parks knives are just hair under 1/8... about .015 thinner than the replacements. To get mine in, I had to make sure everything was spotless - there was no tolerance for error.

I ended up removing the chip breakers, which have ridges running down the side that meets the screws, and lapping the ridges down a hair with some sandpaper on a flat surface. This ought to give you a little more slop to play with them in the future.

Don't try to force the jack screws, you definitely don't want to strip them.
I'd use an icepick/scratch awl or something similar and tapered to get under the edges of the knives from the side.

It's definitely worthwhile to throughly clean the threads on the 15 grub screws for the knives as well. I used a lot of oil and a small metal brush intended for cleaning the I.D. of pipes.

[dan petroski]

just completely rebuilt a parks planer. all my screws were frozen. use half and half acetone and atf or pb blaster as a penitrant. be patient. i cut off an allen wrench so i could tap on it to loosen them. squirt tap squirt tap. good luck with it.

[Chip Lindley]

A *little* heat couldn't hurt with a propane torch. Just blow out any penetrating oil first, for fire safety!

[dan petroski]

because of the mass of the machine and the location of the screws i felt that heat was not a workable option in this case although that procedure works well in other places. trying to heat a 4 inch dia rod to remove a 3/8 screw will be tricky.

[Bill Orbine]

Had the same problem with loosening the set screws for the planer knives. Patience and working at it was the key. The heat didn't help much. One thing I did was insert hexagon bar (cut off leg of allen wrench) and give a good blow with hammer and with a wrench on the hexagon bar to loosen screws. That helped big. Cutting off allen wrench leg helped give a more direct blow to the screws.

[tim weidman]

thanks to all for your input. this machine was in unheated workshop when i bought it and its now in my unheated garage. probably half the reason for the stuck screws. got most of the screws loose but could not get knives out. ultimately i consulted owwm web site {great source of info!!!!} on pointers to get the cutter head off. removed gear box and cutter head and was able to get more of a straight shot with a screw driver underneath knives. got 2 out but a few screws still need a soaking to loosen up. at least i know i am on the rite path! thanks agian.