# Is upgrading to G0761 worth it?



## Investigator (May 1, 2019)

I'm considering a new mill.  I currently have a RF30 clone round column mill, very similar to the G0760.  I am wondering about how much real difference I would see if moving to a square column such as the G0761.  I already am aware of the limitations of the round column losing zero when raising the head.  That has not been an issue as I can plan to work the height of the head as I plan the work.

I really would like to hear from folks who have used both the round and square column machines.  Do you notice the difference?


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## martik777 (May 1, 2019)

I wouldn't bother, especially if raising the head has not been an issue for you. I have found my RF30 just as rigid as square columns in the same price range. I would really miss the ability to swing the head too,


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## mikey (May 2, 2019)

If I switched from my RF-31, I would go for a knee mill. Your current mill is stout enough for most hobby work and I'm not sure that a square column is enough of an advantage to warrant the expense. A knee, now that would be worth an upgrade to.


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## Investigator (May 2, 2019)

thanks.  My scenario is I'm trying to sell a lathe and was thinking of using the money to buy the mill.  I can always use the money to but other stuff.

Thanks for the input


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## markba633csi (May 2, 2019)

Are you selling the Logan? 
M


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## Investigator (May 2, 2019)

no II lathe that I got at the same time the 16 in South Bend


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## Titanium Knurler (May 2, 2019)

I know you are looking for input from users who have had _both _round and square column machines.  I have not had both types of machines but I do have the Grizzly G0755 (https://www.grizzly.com/products/Grizzly-Heavy-Duty-Mill-Drill-with-Stand-and-Power-Feed/G0755) and have been very happy with it.  It looks to be very similar to the G0761 you are considering except for the motorized headstock elevation and the cast iron stand.  I would really miss the dovetailed column because I do tend to raise and lower the head for various operations and it is very nice to keep it registered but it sounds like you would not like to go without the round column of your current machine so I seems like staying  with your current machine is best, especially since you will probably take a hit when selling your current machine.  Just my .02


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## Investigator (May 2, 2019)

Titanium Knurler said:


> ..... I would really miss the dovetailed column because I do tend to raise and lower the head for various operations and it is very nice to keep it registered but it sounds like you would not like to go without the round column of your current machine......


Kim

I have no attachment to the round column I own. I would not miss it if it suddenly became a square column.  I am aware of it's issues, and have been able to work within them so far. My main question was just because I don't know how much I don't know.


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## Titanium Knurler (May 2, 2019)

Well, I admit I don't know much but I do like the square column.  For example, I have a project planned for this weekend where I will be drilling a hole and then reaming it to get a nice fit.  I like using short drill bits for their rigidity but the reamer is about 8-10" long.  Since the head has limited quill travel my choice is to shorten the reamer or raise the column.  Not sure which I will do yet but at least I have a choice.  

BTW, I got your comments mixed-up with martik777 comment about missing being able to swing the head-sorry 'bout that.


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## BGHansen (May 2, 2019)

I had a Grizzly round column mill (G0760) and switched to a Jet JVM-830 (comparable to a G0731) small knee mill, so not your  round to square move but similar.  For me it was a very good move.  I made a riser block for the JVM which got the table 18" from the spindle instead of the stock ~12".  So nice to move the table up and down with tooling changes and not worry about refinding zero.  I was poor at planning the tooling moves with the round column; should have laid everything out on the table to start with and decide where to set the quill for establishing (0,0) to start with.  Had I to do it all over again with a round column, I'd set each tooling set up on the table and take some measurements:  drill chuck with a jobber drill would be the longest, collet with an end mill the shortest - hopefully less than 5" difference in length or you'll need to find center again.

I came up with a workable re-find (0,0) with my round column.  I doweled a block of CRS to the top of the mill vise ahead of the fixed jaw.  Then zero'd on the LH corner of the vise jaw and machined the block edge at (0.900, 0.900).  Mechanical edge finders are cheap; made up extension rods at 5", 10" and 15" with a mechanical edge finder in each one.  I recall using 3/8" or 1/2" drill rod and made bushings out of 1/2" or 3/4" drill rod that pressed onto the 3/8" or 1/2" rod at one end of the bushing and pressed a 3/8" or 1/2" shank edge finder in the other end.  If I had to move the column, I'd pop in a 3/8" or 1/2" collet and the appropriate extension rod/edge finder and re-find the corner on top of the vise jaw.  I used the 0.200" tip edge finders, so zero'ing on a block at (0.900, 0.900) got my hand wheels zero'd out at the corner of the vise again.  If the work was bolted to the table and not the vise, I'd zero off a 1-2-3 block or some feature on the part and go back to the same spot if I had to crank the head.  Nice thing about the mill drill was the cranks were 0.100" per turn, so didn't need to compensate for the 0.100" radius of the edge finders.

Have fun shopping!

Bruce


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## mikey (May 2, 2019)

Investigator said:


> I have no attachment to the round column I own. I would not miss it if it suddenly became a square column.  I am aware of it's issues, and have been able to work within them so far. My main question was just because I don't know how much I don't know.



You know enough, Scott. What you gain with a square column is that your head position remains square to the work as you move it; that's basically it. Of course, with the power down feed and other modern features the G0760 has it would be a nice upgrade but only you can determine how valuable they are. You already upgraded your spindle so you present machine is already accurate. 

I have asked myself the same question - should I upgrade my mill? After a lot of reflection, I have concluded that my RF-31 does what I need it to do. If I switched, I would go straight to a knee mill for the added rigidity. I feel that any mill in which the head moves cannot be as rigid as a knee mill, where the head does not move. For me anyway, that is the only upgrade worth the cost.


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## martik777 (May 2, 2019)

Consider spending the cash on a power feed and/or DRO


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## Investigator (May 2, 2019)

martik777 said:


> Consider spending the cash on a power feed and/or DRO



My RF30/31 (honestly I'm not sure which one to call it, I've upgraded the bearings as Mikey said.  I'm going to call it a RF 30.5) already has DRO's added.  They are not the top of the line. I used the Igaging absolute I think.  They work for me and it was a great upgrade.



mikey said:


> You know enough, Scott. What you gain with a square column is that your head position remains square to the work as you move it; that's basically it. Of course, with the power down feed and other modern features the G0760 has it would be a nice upgrade but only you can determine how valuable they are. You already upgraded your spindle so you present machine is already accurate.
> 
> I have asked myself the same question - should I upgrade my mill? After a lot of reflection, I have concluded that my RF-31 does what I need it to do. If I switched, I would go straight to a knee mill for the added rigidity. I feel that any mill in which the head moves cannot be as rigid as a knee mill, where the head does not move. For me anyway, that is the only upgrade worth the cost.



I think you are right, going to a square column wouldn't be enough of an upgrade to make it worth the trouble and cost.  When I sell the Southbend, I'll look around a bit for a knee mill since I have the room.  If not a knee, I'll keep trucking with what I have.  I've been impressed with what I can do with it so far.

I do wish I had a better vise though.


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## mikey (May 2, 2019)

Investigator said:


> I think you are right, going to a square column wouldn't be enough of an upgrade to make it worth the trouble and cost.  When I sell the Southbend, I'll look around a bit for a knee mill since I have the room.  If not a knee, I'll keep trucking with what I have.  I've been impressed with what I can do with it so far.
> 
> I do wish I had a better vise though.



I have a few more things to get done before I review the True Line 8 but that might be worth emulating if it works. We'll see, but if it does work then it would be a heck of a lot cheaper than buying a new mill and would give you the primary advantage you are looking for. 

The vise is easy - buy a Kurt/Glacern/Parlec vise. I know you're already clear on how important a good vise is so I'm preaching to the choir.


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## Investigator (May 2, 2019)

mikey said:


> I have a few more things to get done before I review the True Line 8 but that might be worth emulating if it works. We'll see, but if it does work then it would be a heck of a lot cheaper than buying a new mill and would give you the primary advantage you are looking for.
> 
> The vise is easy - buy a Kurt/Glacern/Parlec vise. I know you're already clear on how important a good vise is so I'm preaching to the choir.



 we'll get a better Vice at some point but I will probably wait a bit until I am better than the vice I have


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## Mitch Alsup (May 3, 2019)

BGHansen said:


> I had a Grizzly round column mill (G0760) and switched to a Jet JVM-830 (comparable to a G0731) small knee mill,



This, upgrade all the way to a knee mill; or stick with what you have.


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