New Grizzly G0796 Mill For $4750?

I wonder if they have pre-sold all of the first shipment?
 
tmarks11 said:
To be fair, the Grizzly store has never had more than two people in it any time I have been there. Fortunately work sends me through Bellingham on travel once or twice a month.
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Maybe its not open on Saturday because its way the hell up in the middle of nowhere near the north pole!! ;)

Ditto on the hate of the hot weather, and my 3 car garage shop is fully insulated and the 2nd floor of the house extends over part of it. But then I have no tolerance for heat, I keep my house at 66 degrees year round I don't care of the AC burns out and starts on fire!!
 
I called Grizzly Friday and was told they are to be available at the Washington warehouse in mid Sept. I'm really close to pulling the trigger on this, got the money burning a hole in my pocket.
 
Hi sanddan: Please be aware that this could be quite a wait time and nobody knows when they will be coming in. I was first told that the mills would be available in April of 2015 one month after I paid for it. Every month the date has been pushed out 30 days since then. I also spoke to Grizzly on Friday afternoon and after speaking with Carly, then Robin, then Jean who is a supervisor, I was told that they do not KNOW when the mills will be coming in, they have estimated delivery dates only and that they can change depending on whether the factory ships the product or not. This is all well and good, I now have zero problem with the wait time. My complaint has never been the amount of time I have to wait, I have a great milling machine in my shop already (A G0704 Grizzly), I do not mind the wait, what I do mind is being told a date that gets pushed out over and over. If they do not know when something is going to arrive they should not set a date. So, please keep in mind if you do buy one of these that it may take six months or any other amount of time to arrive.

Barry
 
A couple of observations and a question for anybody who understands this motor stuff.

Since photos of the G0796 is the wallpaper photo on all of my computers here at the house as well as my computers at work, I have had a great deal of time to examine the photos. I noticed some things while comparing them to the Bridgeport at work, mills from my working past, and photos online. Here we go:

A: The 3HP spindle motor on the G0796 has a bulge on the side for a starting capacitor. The Bridgeport brand mills and 99% of clones do not. Both are listed as induction motors, there are however IMHO different kinds of induction motors and I do not understand all the nuances of the different types. When tapping in Bridgeport mills, I often chuck the tap in a keyless chuck start the spindle motor, and then gently plunge the tap into the hole reversing the motor to unscrew the tap after reaching desired depth. My question is this, will the capacitor type induction motor on the G0796 reverse as quickly as the motor on the Bridgeport or will I have to wait for it to coast to a stop before reversing it? Any help anybody has will be greatly appreciated.

B: The power feed on the X axis looks a bit wimpy with sort of a limp hello kitty plastic toy appearance. It is not. I have done a bunch of digging based on the photos on Grizzly's website. The Aclass TonE designation on the power feed got me nowhere. Enlarging the photo showed a model number APF500 and this did lead somewhere. This is a very good aftermarket power table feed with some outstanding features and people seem to be very happy with it. The manual for this power feed can be found here:
http://modelengineeringinthailand.com/wp-content/uploads/2014/08/manual-em_a_class_power_feed.pdf
These power feed units are all over ebay. I think if you wanted one for the Y axis it would not be difficult to find one that matched.

C: The spindle transmission looks to be an identical clone of the old Bridgeports I ran when I first started in the trade in the 80's. This transmission has two knobs a lever on the top of the mill with a diagonal slot and a two position "pull, rotate, release the knob" lever above and to the right of the quill depth stop. This is a VERY good thing if it is an identical transmission including the metallurgy in the gears which may be suspect. Those Bridgeports I started on had been working every day since the 60's under harsh heavy duty conditions and during my three years at that company I never saw one worked on at all. The other Grizzly mills have transmissions that are different, the G9901 for example has some odd transmission with a lever above and to the left of the head which for a short guy like me is an issue. While in the showroom one day I fiddled with the transmission on the G9901 and it seemed a bit flaky, the lever flexed and it did not slide into gear like the Bridgeports I had run, it sort of begrudgingly snapped, or fell into gear. This probably does not amount to a hill of beans especially for the grotesquely tall operator, but it was a welcome observation to me and the other little people. Hopefully it means the mill will come (if it ever comes), with a top drawer transmission. There is also the possibility that original Bridgeport parts may fit, that would be a huge plus from where I stand.

D: The weight of the G0796 as listed in the specification sheet on the Grizzly website (Wish they would post a manual) is 2249 pounds. The standard belt drive Series I J head Bridgeport weighs in at almost 2400 pounds. So we are within about 150 pounds of the real deal. That was a bit of a concern to me until I noticed two things from the photos, the hole in the bottom of the knee is enormous compared to a Bridgeport knee, this will make the mill considerably lighter. Also, the ram is a humpback style ram like on the most recent Bridgeports. This is a considerable weight reduction too. So I feel that the difference in weight will have no impact on the performance of the mill. This again was a good observation.

E: The plastic on the spindle control switch looks a little cheesy. It looks brittle. What do you think?

Every time I look at this mill it gets better. It sucks to have to wait for it, but the wait will probably be worth it.

Barry
 
Have any of you considered CNCing the G0796? I purchased a four axis CNC conversion kit from Automation Technologies to convert my G0704 mill about two years ago before I even started shopping for a Bridgeport clone. When I bought the kit I wanted a big enough one so that if I ever wanted to migrate it to a big mill I would have the power. Some research revealed that most people who had 500 in/lbs or more torque on the Bridgeport conversion motors were happy and those with less complained of stalling during cuts. Here at Overengineering Central that sent a clear message that two times adequate is a good starting point. I found a four axis kit with 1125 oz/in monster motors. The electronics for the power supply, Gecko drives, breakout board, and all that fit into a nice black diamond plate toolbox I found at Home Depot. That took two years of fiddling with to get right and it is now working like a champ thanks to my Co-Instructor Denny. The ball screws I bought for the G0704 will probably have to go on ebay since I intend to CNC the G0796 as the first project. So I will make X left and right, Y in and out, Z the quill up and down and W the knee up and down. I will probably have to counterbalance the knee. So think about CNC, this is a great platform for a good conversion.

Barry
 
barryjyoung said:
A: The 3HP spindle motor on the G0796 has a bulge on the side for a starting capacitor. The Bridgeport brand mills and 99% of clones do not. Both are listed as induction motors, there are however IMHO different kinds of induction motors and I do not understand all the nuances of the different types. When tapping in Bridgeport mills, I often chuck the tap in a keyless chuck start the spindle motor, and then gently plunge the tap into the hole reversing the motor to unscrew the tap after reaching desired depth. My question is this, will the capacitor type induction motor on the G0796 reverse as quickly as the motor on the Bridgeport or will I have to wait for it to coast to a stop before reversing it? Any help anybody has will be greatly appreciated.
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There are instant reverse single phase motors, but I'm guessing this is not one of them. So yes, you probably have to wait for it to coast down. If I were going to buy that mill, I would try to get it with a 3 phase motor and put a VFD on it.

That is a BP clone head. What's inside? Who knows. It may be a high quality machine, or not. The price of the machine is pretty low, but Grizzly seems to sell some reasonable quality equipment a low prices.

The spindle switch looks to be typical Chinese, so will proabaly fail. The good news is that there are good American branded (probably not made in America any longer) switches available for a semi-reasonable price.
 
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Thanks Jim. Guess I will have to learn how long it takes to stop. That is bad, but there could be much worse things about this mill than that.

Barry
 
barryjyoung said:
So I will make X left and right, Y in and out, Z the quill up and down and W the knee up and down. I will probably have to counterbalance the knee. So think about CNC, this is a great platform for a good conversion.
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The normal convention is -X = table moving to the right, +X = table moving to the left, -Y = table moving towards the column, +Y = table moving away from the column, -Z = quill moving down, +Z = quill moving up.

I would just put a power feed on the knee, but put a scale on it so you have a readout on the DRO. I have mine labeled as K axis, but is not under computer control, works great for different tool heights, and small adjustments on the fly. The W axis would be a great place to connect the rotary axis that you will ''need'' later. :)
 
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