# limits of G0704



## TRX (May 15, 2017)

I have a project that involves milling four inch slots in 1/4" wall, annealed 4140 tubes. 

It's a good justification for upgrading from my swaybacked antique mill to something new.

I'm tempted to overbuy and go for the G0755 just on general principles, but the G0704 would be a lot easier to get into the shop and shifted into position, has more than adequate travel in all three axes, and I could blow the saved money on a new vise and tooling.

Anyone have any suggestions?


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## Eddyde (May 15, 2017)

I would stick to your principles and get the bigger machine!


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## fradish (May 15, 2017)

You might want to look at the PM25.  That is like the G0704, but with belt drive and variable speed.
I have a PM727 which is similar to the G0795.  That one is a bit bigger than the 704.


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## burtonbr (May 15, 2017)

I know the g0704 will do those slots for you with the right end mill and a lot more, i had one for a while and enjoyed it I was able to do a lot with mine at the time but quickly wanted a larger mill, thinking back I don't remember ever thinking it wasn't rigid enough for what I wanted to do with steel or aluminium in the table or column maybe once while using a boring head for large holes I remember it was a bit much for it , I like variable speed think that's a must for me. I think the spindle and motor is the g0704 weak link but within its limits you can do a lot with one and I felt like I could hold good tolerances once I learned the machines capabilities.
I would recommend if you can afford more and can support a heavier machine you will be glad you did as it's easy to want more machine quickly, have you checked out the PM-727 or the PM-30 those are a little bigger but also almost 2x the cost. I had all but placed an order on a 727 before I decided on a CNC mill.
Good luck deciding


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## kd4gij (May 15, 2017)

You didn't say the with of the slots. But I would have no problem doing it on my G0704


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## TRX (May 16, 2017)

Thanks, guys!

For you Precision Mathews fans, I don't have anything against PM, it's just that Grizzly's Missouri warehouse is close enough for me to drive and pick the machine up, and close enough to go beat on their door in person if I have a customer service problem.

I know there are variations between the RF45 and BF20 machines from the various importers, but it looks like they average out to "six of one, half a dozen of the other" as far as my requirements.


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## burtonbr (May 16, 2017)

Yea that's a no brainer then if you can pick it up from grizzly and save shipping, possibly you can get a deal at the tent sale in a couple weeks.


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## fradish (May 16, 2017)

That is one of the reasons I went with PM, they are about 1/2 hour away from me.
I picked my lathe and milling machine myself.  I'm sure you'll be happy with
whatever Grizzly you choose.  Personally I would look at the G0795 (similar to
the PM727) as it is a little bigger than the G0704.  Especially in spindle to table
distance. 

I know you can drive yourself crazy thinking that you should keep going bigger,
but picking a machine at least a little bigger than what you think you need now
is probably a good idea to allow you to grow into it as time goes on.


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## TRX (May 16, 2017)

Aaargh!

Somehow I'd missed that one.  I think you just cost me $525.00...


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## fradish (May 16, 2017)

I'm assuming that you've downloaded the manuals from Grizzly's site?  They can be really
helpful in understanding the differences between the machines.  There should be links on
the same page that you would order from.


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## burtonbr (May 16, 2017)

I would have to go for the  G0720R, it's only money right .


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## RodSME (May 18, 2017)

I have a G0619 that I bought on CR.  It's a nice machine but I quickly learned that it is too light weight for a lot of the jobs I like to do.  The column isn't stiff enough in torsion (another story).  I wish I'd have spent the money on the heavier mill such as the G0755.


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## MontanaAardvark (May 19, 2017)

Someone once told me the answer to "how big a (lathe, mill whatever) should I buy?" is, "you'll always need one about 1" bigger than what you have".  

For what it's worth, my rule on tools is to get one that seems like a good combination of features for what you can think of now.  You'll always want to work on something bigger.  

Yes, I have a G0704.  Converted it to CNC and have used it on projects well within its work envelope, so far.  I thought it was a pretty decent mill right out of the box.  I already have about the same cost in the CNC additions as the original machine, and I'm looking at a new spindle.  It's not that the spindle is bad, it's just slow for a CNC mill and I'd like to be able to control it from the CNC program. 


FWIW,
Bob


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