Grizzly G0634XP J/P Combo head

[Curt Harms]

I just got the Spring sale flyer. I'm not in the market but the G0634XP has an introductory price of $2195. That's a pretty attractive price for a 12" J/P with a spiral head. The head is what made me go "hmmmm". The spec sheet says it's 12" but has 32 inserts. It has 4 rows of cutters so that looks like 8 carbide cutters/row. That seems to me like each insert would have to be 1.5"--1.5 X 8 = 12 cutters/row. From the spec sheet page 2:

Cutterhead Information
Cutterhead Type.............................................. .................................................. .Spiral
Cutterhead Diameter. .................................................. ..................................3-1/8 in.
.
Number of Cutter Spirals........................................... ...........................................4
Number of Indexable Cutters........................................... .................................................. .....................32

Cutter Insert Type.............................................. ......................4 Sided Indexable Carbide
Cutter Insert Length............................................ .................................................. .................15 mm

Cutter Insert Width............................................. .................................................. ..................15 mm
Cutter Insert Thickness......................................... .................................................. ..............2.5 mm
Cutterhead Speed............................................. .................................................. .............5034 RPM

Some sort of typo? 8 15 mm inserts covers 120 mm. A 12" head is approximate 310 mm. That's a compelling price and it has the end mounted fence so it can sit up against a wall. What am I missing?

http://www.grizzly.com/products/12-Planer-Jointer-with-Spiral-Polar-Bear-Series-/G0634XP

[Rod Sheridan]

Curt, it may not be a typo, they may be staggered so that each spiral cuts certain strips of the board, the other spirals cut the remaining strips...........Regards, Rod.

[jonathan eagle]

I should be getting my g0634xp later this month, and the hammer bandsaw, Rod talked me into getting.
Jonathan

[Matt Day]

Remember there are "4 rows of Spiral Cutters", which is different than 4 straight knives. The spiral cutters are likely spaced apart, kind of like this:
http://www.toolking.com/1/powermatic_1791212_byrd_shelix_insert_cutters_10_p ack_10536359.php

[John Gornall]

I've been asking this question and haven't got an answer. If you go to this page:

http://www.grizzly.com/outlet/12-Jointer-Planer-w-Spiral-Cutterhead/G0634

And look at the pictures (run your curser over the pic and it will enlarge) and I think you'll agree there are more than 32.

I think there are 60 - definitely more than 8 in each row.

[Chris Ricker]

John;
You are correct. I believe the picture you pointed out is of the models prior to 2008 (?). I purchased my GO634 in 2007 and it had 4 rows of 14 bits in each row for a total of 56 cutters. the newer models (2008 or 09) have a redesigned cutter head that has 32 cutters.
Curt;
I have not heard of any complaints regarding the newer head design and I can't attest to it but, I have no complaints about my 2007 model.
Best of luck
CR

[Steve Baumgartner]

I too am contemplating this combo vs the Jet JJP-12HH, and wondered about the number of cutters. Seems like a cost-cutting move rather than a design improvement. I understand how the cutters on the multiple spirals can be offset so that eventually a cutter hits each part of the width even though they are less than width/number. But wouldn't that cause added vibration and possible waviness in the surface compared to a head with more inserts? Sort of like a standard head with fewer blades? Has anyone out there done or seen a side-by-side comparison with a machine having more inserts per spiral?

[jonathan eagle]

Steve,
I am due to get this machine in the next day or so. It's in town.
When I actually get it into my shop, I'll let you know what is up.
I would read about the issues folks are having with the jet motors.
Jonathan

[Steve Baumgartner]

Thanks, jonathan! The issues with the motors and with jointer tables sagging do give some pause with regard to the Jet.
Steve

[jonathan eagle]

Steve,
I got my g0634xp Friday and it is now moved into my shop.
I can't find my camera, but it does have 32 cutters. They are 8 across in each helical line. Each line has it's first cutter at a different offset, so they overlap.
It is still covered with cosmolene, needs to go through the usual adjustment testing for any new tool. It looks very nice. Came through visually perfect. The crate was shot.
I hired two guys to help me get it down my basement stairs. That alone took 2.5 hours. So I'm beat!
Jonathan

[glenn bradley]

Interesting that my 8" has 40 inserts and my 15" has 74(?). I suree there are design parameters involved that are way outside my area of expertise and the cut quality is reportedly quite good, probably just less overlap.