Dave Cav
09-02-2008, 12:23 AM
I just finished installing a Grizzly helical head in my 15" Grizzly planer. The procedure was identical to Frank Snyder's excellent writeup http://www.sawmillcreek.org/showthread.php?p=491717#post491717, so I won't repeat everything he has already written, but I will mention a few things I learned during the procedure.
Plan on taking three to four hours for the complete process. If you are an experienced mechanic it might take a little less, but give yourself plenty of time. An assistant would be helpful, but I was able to do all of the work by myself without too much trouble. The gearbox/cutterhead assembly is pretty heavy and awkward, so be careful when removing and reinstalling it. Finally, have lots of rags around to clean up spilled gear oil. I suggest you refill the gearbox before you reinstall it; it is easier to get the oil in it that way, and if it leaks, it's easier to fix.
Grizzly packs their head in Styrofoam and a heavy cardboard box. I picked mine up at Bellingham, so I don't know how well it will ship packed that way; hopefully they will put it in a bigger box full of plastic peanuts. The cutter head came wrapped with multiple layers of saran wrap. During the installation process, I also wrapped it with several layers of newspaper and masking tape to protect both the head and my hands.
The process was a little messy, because I didn't completely drain the gearbox. You can't get all of the oil out with the gearbox installed in the planer, but if you remove the gearbox/cutter head assembly and lay it down with the drain hole down most of the oil will drain out. On the other hand, you can just put a bunch of rags or newspaper on the workbench and then pull the cover off and let the remaining oil run out that way.
I had exactly the same experience with the gearbox cover as Frank; when I reassembled it and filled the gearbox, oil ran out one side. I drained it again, pulled the cover, removed the (plastic) gasket, and carefully wiped everything down. I noticed a burr on the cover where I used a chisel to loosen it, and filed it down smooth, then put a good coating of RTV silicone on both sides of the gasket. I put all of the bolts and the two locating dowel pins back through the cover, and put the cover and gearbox guts back into the gearbox. With the bolts and dowels to guide it on, everything snugged back down and didn't leak the second time.
I also had a little trouble on the initial gearbox disassembly. Some of the gears and bearings stayed in the gearbox. I had to pull them out and then figure out how to get it all back together on the cover. Once I got all the gears in place it was obvious how everything worked, but for removing the cutter head and later reassembly, you want all of the gears and bearings on the cover, not in the gearbox.
My instructions said to thread a "spare" M6 bolt into the end of the cutter head assembly and drive it out of the gearbox bearing with a hammer. That didn't work at all, so I used my hydraulic press to press the cutterhead out of the bearing in the gearbox.
Reassembly was pretty straightforward, and the new cutterhead works great. I ran an assortment of wood through it and everything came out looking very good.
Let me know if you have any questions.
Dave C
Plan on taking three to four hours for the complete process. If you are an experienced mechanic it might take a little less, but give yourself plenty of time. An assistant would be helpful, but I was able to do all of the work by myself without too much trouble. The gearbox/cutterhead assembly is pretty heavy and awkward, so be careful when removing and reinstalling it. Finally, have lots of rags around to clean up spilled gear oil. I suggest you refill the gearbox before you reinstall it; it is easier to get the oil in it that way, and if it leaks, it's easier to fix.
Grizzly packs their head in Styrofoam and a heavy cardboard box. I picked mine up at Bellingham, so I don't know how well it will ship packed that way; hopefully they will put it in a bigger box full of plastic peanuts. The cutter head came wrapped with multiple layers of saran wrap. During the installation process, I also wrapped it with several layers of newspaper and masking tape to protect both the head and my hands.
The process was a little messy, because I didn't completely drain the gearbox. You can't get all of the oil out with the gearbox installed in the planer, but if you remove the gearbox/cutter head assembly and lay it down with the drain hole down most of the oil will drain out. On the other hand, you can just put a bunch of rags or newspaper on the workbench and then pull the cover off and let the remaining oil run out that way.
I had exactly the same experience with the gearbox cover as Frank; when I reassembled it and filled the gearbox, oil ran out one side. I drained it again, pulled the cover, removed the (plastic) gasket, and carefully wiped everything down. I noticed a burr on the cover where I used a chisel to loosen it, and filed it down smooth, then put a good coating of RTV silicone on both sides of the gasket. I put all of the bolts and the two locating dowel pins back through the cover, and put the cover and gearbox guts back into the gearbox. With the bolts and dowels to guide it on, everything snugged back down and didn't leak the second time.
I also had a little trouble on the initial gearbox disassembly. Some of the gears and bearings stayed in the gearbox. I had to pull them out and then figure out how to get it all back together on the cover. Once I got all the gears in place it was obvious how everything worked, but for removing the cutter head and later reassembly, you want all of the gears and bearings on the cover, not in the gearbox.
My instructions said to thread a "spare" M6 bolt into the end of the cutter head assembly and drive it out of the gearbox bearing with a hammer. That didn't work at all, so I used my hydraulic press to press the cutterhead out of the bearing in the gearbox.
Reassembly was pretty straightforward, and the new cutterhead works great. I ran an assortment of wood through it and everything came out looking very good.
Let me know if you have any questions.
Dave C