My New Grizzly G0678 Knee Mill

DoogieB

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Well, I have been sitting on these pictures long enough so here's a post about my new mill, a Grizzly G0678. It's a 8x30, variable-speed knee mill.

A little background. I've been shopping for a mill since the day after I bought a 1974 South Bend 10K lathe. I couldn't handle a Bridgeport-size mill in my tiny shop, but wanted something a bit bigger than the G0704 that popped-up on CL 5 miles down the road. For vintage equipment, that meant a Clausing 8530, Rockwell or maybe a Millrite. For new equipment, one of the many RF-45 clones. At the time, I was also limited on what I could get on and off the bed of my truck with an engine hoist.

So fast-forward a year and I still didn't have a mill as all the likely candidates were either too far away, just plain scrap or gone before I could make a move because of work or other commitments. Things were looking-up, however, as I was planning on getting a different truck with a hitch so I could use a trailer. This meant much easier loading and unloading, so I could now go after a slightly bigger mill, while still trying to keep it under a 1000 pounds.

In the spring, I drove up to the Muncy story to lay hands and eyes on machines. What I found was that the Taiwan machines were definitely a few rungs higher on the food chain and that I greatly preferred to operate a knee mill. So the new plan was to watch CL for another year for a small knee mill, with a Plan B of buying a new mill at Muncy when I had enough waiting.

And then a month ago Grizzly decided to close the Muncy store! It was time to poop or get off the pot. With the discounts they were offering at the store, Plan B was going to cost at least $800 more next year and I wasn't exactly seeing a ton of likely candidates on CL and Ebay. The small mills are rare and sell quickly if they aren't scrap. So this followed me home that Friday.

mill_1.jpg

Here you can see the mill being pulled off the trailer. You are looking directly at the spindle (R8) as the head is tilted so it would clear the garage door while sitting on the trailer. Since this was a last minute deal, it took me a week to get the shop ready.

mill_2.jpg

And here the mill is being dropped onto the mobile base. Grizzly had all their machinery in the showroom on these things and it was a freebie since I bought a floor model. It was way too squishy to leave under the mill without some work, but it sure came in handy to push it into the shop as it saved me having to use black pipe. As you can see, the base just fit inside and under the engine hoist.

mill_3.jpg

And here's the mill in it's spot in the shop, doing a little work. I'm still getting used to it, but I like it so far and I'm improving the arrangement as I go. Next improvement will be in the lighting situation with a spindle LED ring.
 
A little more about the mill.

The G0678 is cousin of the 6x26 class of mills which are a knockoff/update of the Clausing 8520/30 family. These mills have been imported from Asia for a long time now for several different retailers. The 6x26, while having a few improvements from the Clausing like an R8 spindle, shares one of the problems of it's ancestor with a short spindle-to-table distance. Riser blocks are a common upgrade for this mill.

The 8x30 mills like the G0678, along with a slightly larger table, have the riser block function achieved by a different column/base. The maximum spindle-to-table distance of this mill is 20 inches compared to 12 inches for Grizzly's 6x26 model.

All the extra cast iron pushes the weight of this mill to just a hair under 1000 pounds. This mill was made in Taiwan.

A great feature of the G0678 is the 3-phase motor and speed control with a Yaskawa VFD.

mill_4.jpg

As you can see, power transfer doesn't get much simpler: 1 belt and you don't ever need to touch it.

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Here's the control panel, the red button is the spindle on/off button. At first I thought it was a little weird to use an emergency shut-off button as the off, but I guess it doesn't really matter. When your first plug-in the machine there's no visual indication on the panel of power until you twist the red button and then the pilot light on the left lights. Then when you press the green button, a relay snaps in the column where the VFD is located, the digital speed display activates and the mill starts running. Speed is selected by turning the knob and this setting sticks from one session to another. Direction control is via the knob just left of the display.

According to the manual, the speed range of the mill is 200-2250 RPM. This isn't true, as it's actually 0-2250 RPM. I almost had a heart attack when I first plugged it in and it didn't run because the knob was parked at the left stop. :) Initially I was worried about low-end torque with this setup. No worries. One of the first tests of the mill was drilling with a 3/4" taper bit. No issues, tons of torque and the bit went right through. I've done some other screwing around with larger end mills and I'm pretty sure there's plenty of power for what the mill can handle.

With no gears in the drive train and a 3-phase motor, this mill is really quiet and smooth. VFD's totally rock!

mill_6.jpg

Here's a picture showing the one-shot oiler while I was screwing around the gibs. At first my major complaint with the mill was that some of the plastic oil lines were weeping, but after some work refastening the lines they seemed to have gotten better. Compared to my old SB lathe there's practically no maintenance on this machine.

Fit and finish on these imported machines seems to vary a great deal, but I've been pretty pleased with the G0678. I've had the mill for a month now and I've been pretty much been all over it with my Last Word indicator (.0005) and I can't find anything really wrong with it. Obviously you need to do the usual cleaning, setup and tramming and I spent awhile just working with the gibs. One thing that did need adjusted was the nod which ended-up being a simple fix with some shim stock between the column and head. There's a few cosmetic scratches on the table, but it moves smoothly in all directions. There's probably a few other things I can't think of right now but nothing that makes me feel I have to contact customer support.

Wrapping-up, I'm pretty happy to finally have a mill. Right now I'm planning on just settling-in and using the mill as-is for awhile, but future upgrade plans include a 3-axis DRO and x-axis power feed.
 
nice score, sounds like you got a good deal.

Recommend you take the swivel out from under the vise and put it one the shelf until you need it. 95% of the time you won't, and having it on the table makes the vise harder to tram, and reduces rigidity of the setup.

That mill is much prettier than my Clausing 8520.

Conquest Mini-Magnum is an awesome vise. Perfect size for one of these machines.

There's a few cosmetic scratches on the table, but it moves smoothly in all directions.

These things are made for work, not for show. You will be adding your own scratches to it shortly, and you will never even notice the ones it started with.
 
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Nice is nice , yupp sure is. Good luck you deserve it . Thanks for sharing with envy .
 
Very nice setup you have.

I suggest the same as Tim, remove the base and direct bolt the vise to the table. I have found it is very seldom used. I kept mine on my last vise for ten years before I removed it and only used it once in the next six years I owned that mill. I didn't even purchase a rotating base for my new Glacern last year.

Just a suggestion.

Mike.
 
Thats a nice looking machine....

Very similar to my G1008 ..... i just picked up. Ill be doing a VFD to mine soon enough.
 
Conquest Mini-Magnum is an awesome vise. Perfect size for one of these machines.
While it ain't cheap, the Conquest Mini-Mag is a very nice USA-made vise and the perfect fit for this mill. It overhangs the back of the table just a tiny bit, the same as Kurt 4" vise but obviously the 5" Mini-Mag opens wider. These mills don't have a ton of Y travel and I don't want to give any up because of vise interference. Also, for work holding I've been spoiled with a quality Bison chuck that came with my lathe and I figured the milling vise wasn't a good place to start pinching pennies. Tormach also sells this exact same vise under their name.

You guys are cracking me up with the dogpile about the swivel base. Conquest doesn't make a swivel base, the one you see is from a Kurt 5" vise. Kurt hasn't made that size vise for awhile now so when an opportunity came-up to buy a really clean Kurt 5" swivel I bit on it. I was a little nervous at first because a search only pulled one person on da interwebs who tried this marriage, but that fellow was right it works fine once you make a new swivel pin as the hole cast in the Mini-Mag is smaller.

Upon assembly and once I verified with a indicator that the swivel base was nice and flat at different spots, I stowed it on the shelf. Since I do mostly hobby work I sometimes run into some weird setups and my motto has always been "I would rather have it and not need it then need it and not have it." Well, you guys put a whammy on me with your "you ain't gonna need that" talk as I forgot about a little 1 minute milling job I wanted to do and guess what, I need the swivel. Now I got to put the d#@$ thing back on again. :)

The lighting situation is improving:

mill_7.jpg

I took out the 60W burner and went with a 100W (14W really) LED bulb in the factory fixture. While I'm not terribly fond of using a $10 light bulb in machinery, I do really like the high output and daylight light spectrum. It's just so much easier to see details with white light.

The spindle got the angel-eye treatment, It helps, but it's not nearly as bright as it seems in the picture. I'm pretty sure I can fit another larger one around the current LED ring , so maybe having two will help more. It wouldn't be much work to piggy-back another one and the junk box power supply will have absolutely no problems with the load.

The right side of the table is still dark, but I have a good idea how to fix that. It should be a good project for when I have off on Black Friday. It's certainly a lot more fun to hang-out in the shop that join the stampede of shoppers.

Very similar to my G1008 ..... i just picked up. Ill be doing a VFD to mine soon enough.

You betcha, your mill is just an earlier model. Trust me, you WANT the VFD!
 
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