# Grizzly GO 727 mill has grown



## iron man (Mar 18, 2013)

Here is a shot of my Grizzly 727 mill with home built power feed and DRO's it is a nice little mill but like many other Horizontal/Vertical mills such as Atlas they lack room between the spindle and table this one has only six inches. 

This prevents you from using a lot of other attachments and machining odd shapes and sizes this needs to change.


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## iron man (Mar 18, 2013)

So I started out I made a new lead screw 6 inches longer and bigger in dia. I then slugged a steel tube with aluminum and capped and welded the ends the aluminum dampens vibration. I then cut a 55 degree dovetail on to a block of cold rolled steel that will be attached later.


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## iron man (Mar 18, 2013)

Here is the finished product installed works perfect!! The base is a little bigger to give a bigger foot print.


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## iron man (Mar 18, 2013)

And here is the finished product standing much taller. The adapter now gives 12 inches of travel instead of the previous six inches although it takes some planning this is not a hard conversion and it opens up more possible use's now I need buy a longer DRO. thanks for looking.. Ray


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## iron man (Mar 18, 2013)

I use to have only 1/2 inch of clearance between my vise and drill chuck what good is that?? now I have 6 inches that is much better. If I was to do it over of course there is things I would do different but not much this works and worked out very well. I have a one of a kind now as long as Grizzly does not get the hint and comes up with a kit of there own.. Ray


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## iron man (Mar 18, 2013)

I just made to more small modifications I have never worked on a knee mill that did not have a table lock so I drilled and installed one. Also the original mill was suppose to have a removable three pin connector for the motor this comes in handy to service the belt and motor so I installed one of them as well.. Ray


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## Rbeckett (Mar 18, 2013)

Ray,
That is absolutely beautifull work.  And extending the working envelope willl pay many dividends as you find more projects you can now do too.   Is the DRO on the quill or on the knee?  If it is on the quill it will be pretty easy to add another "Axis", otherwise I would leave the quill based DRO alone.  If it is based don the dove tail and column, can you just relocate the sensor into the usable range and call it good, or is a new sensor the only alternative?  Thanks for the great pics of a really great looking project!!!!

Bob


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## iron man (Mar 21, 2013)

Thanks it fits in there just like a factory piece I dont know why I see a lot of these foreign machines that just stop short of making a good product because of a few inches of cast iron it takes just as much material to make a bad product as it does to make a good one.

 I also learned that any of these foreign built lathes and mills you need to go through them and check all bolts every single bolt on this mill was a 1/2 to a full turn loose even the motor brush holders where loose. Ray


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## eac67gt (Mar 21, 2013)

Yep, apparently they don't know how to torque stuff in assembly or it loosens on the boat. :rofl:
Found the same thing on my stuff.

Ed


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## iron man (Mar 24, 2013)

I made another mod to this mill since I made the column longer the small handle to crank the table up was just too small 1 1/2 inches from center to handle it made it feel like the gibs where to tight when in fact they where too loose.


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## iron man (Mar 24, 2013)

So I made a knurled adapter to hold the dial and the crank but still bolted on the stock shaft the handle was welded ,shaped and ground to achive this shape it is now 4 inches long and makes a world of differance. Ray


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## iron man (Mar 24, 2013)

I also made the handle come off to expose  10mm allen wrench I use to reposition the crank and to tighten up my collets on top...


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## cbtrek (Mar 29, 2013)

Grizzly should be reading this form and updating their machine's. All customers would benefit from the improvements that their customer's come up with, free R & D.


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## iron man (Mar 30, 2013)

I just made another update the lead screw that lifts the table was 16 tpi with the present gear ratio that lifted the table 1/32 per rev. I now made a new Acme screw 3/4 dia at 8 tpi this gives me 1/16 per rev. and makes the dial direct read instead of indirect.


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## cbtrek (Mar 30, 2013)

I always wanted to make a Acme screw. Got to make one sometime.


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## iron man (Mar 30, 2013)

Here is a shot of the new lead screw with the stock old one next to it the new one I made is 8 TPI the old is 16 TPI the new one has a brass lead screw nut the old one is cast.

View attachment 50901


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Sorry about the poor quality of the photo but here is the new longer DRO I installed I will build a cover for it next.. Ray


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## iron man (Mar 30, 2013)

After mounting the DRO's I made some covers to protect the DRO sending unit from chips. I bent these up out of pre-painted aluminum. Ray

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Here is the one for the crossfeed.. Ray


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## 8ntsane (Mar 30, 2013)

That is a great line up of mods you have done to your mill. Seeing what it was, and all you have done, makes me wonder why they didn't make them this way. Maybe you should make up a kit to sell with all your improvments.

Great looking job  :thumbsup:


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## cbtrek (Mar 31, 2013)

This shows you can make big improvements to the original design.


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## iron man (Mar 31, 2013)

I will be visiting Grizzly's main store this spring maybe I better bring some photos.. Ray


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## iron man (May 4, 2013)

I made another small modification to my mill I never cared for the aluminum and plastic handles of the mill so I got a pair of traditional chrome spoked one's from grizzly remachined them to fit and then made my own aluminum handles. I have a habit of grabing the outside of the wheel and turning it slowly for fine adjustments and I just could not get use to the square cornered aluminum ones.

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Another shot of the crossfeed and knee handle.

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There was enough meat on each handle to machine for the dial.


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## silence dogood (Jul 12, 2013)

Hope this goes right this time
Iron man,
I've been looking at mini mills.  However I'm not really comfortable with a lot  of the designs, until I saw the Grizzly go727 or the Sieg u1.  I'm only a couple hundred miles from the Grizzly store north of Seattle so I'll be able to get a first hand look.  Your modifications have really impressed me and I'm now leaning even more towards this particular machine.   Thanks.  
Silence Dogood


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## iron man (Jul 18, 2013)

I have added a Grizzly angle table to my arsonal of stuff and with the increase head height it works great I am now making another modification I am making a new spindle and motor arangement that will stay for the horizotal part that way I dont have to pull the motor off the top everytime I want to go with a horizontal cutter. I will post some pic's soon.. Ray


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## j ferguson (Nov 29, 2013)

Ray,
finding this thread and being prevented from reading it until I signed up made me sign up.  I've been away from a serious shop for about 55 years, but now have time and wherewithal to get into it again.  When you say you "slugged" the tube with aluminum, what did you mean?

thanks much for all the detail you have provided.

john


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## iron man (Nov 29, 2013)

j ferguson said:


> Ray,
> finding this thread and being prevented from reading it until I signed up made me sign up. I've been away from a serious shop for about 55 years, but now have time and wherewithal to get into it again. When you say you "slugged" the tube with aluminum, what did you mean?
> 
> thanks much for all the detail you have provided.
> ...




A friend of mine gave me a chunk of aluminum I did not have anything to make out of it so I bored a hole through the center and pressed in a steel 1 1/4 dia. shaft through the center about 14" long. I then machined both surface's without taking it out of the lathe so they where both perfectly flat and square with one another. 

I then cut down a piece of 6" square tubing so the outside measured 5 1/8 X 6" I put the aluminum rectangular aluminum (slug) inside the steel tube. I then placed a plate on the top and bottom to cap the ends I clamped it down hard to the aluminum slug giving me a nice flat surface to clamp to with the 1 1/4 shaft still sticking through each end I then welded everything up. I then chucked it up again in my lathe and surfaced both ends and then cut off the shaft flush with the plates.

Now did I have to do all that NO I did it because it seemed like a good use of material. If I had to do it over and I may I would just use the heavy square tube leave it hollow. I would then screw in studs on the back of the dove tail piece and put nuts on the inside to hide how it was secured this would also allow more adjustment but I spent a lot of time getting this one right and it works great. I did not have to go as tall as I did I could have just stayed at about 3" high and for the most part that would be enough. It is a worth while and easy conversion it is no different than a lathe bed extension except I made a longer lead screw. Ray

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You maybe interested in this thread as well...

http://www.hobby-machinist.com/showthread.php/17466-One-last-Modification-on-the-GO727


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## j ferguson (Nov 29, 2013)

Thanks much, Ray, for the added detail.  Did you heat treat the added dovetail way or was cold rolled good enough?  I'm having to really plan my approach to all of this because I'm going to have to bootstrap my shop (use early tools to modify themselves).  

There's a big difference from moving into a shop that's been performing for 40 years and starting from scratch.  Looking at your mods carefully, it really does make you wonder why that column couldn't have been 3 inches taller, as you say, probably enough.

best regards,

john


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## Dave Smith (Nov 29, 2013)

Ray---I just read through all your posts on this thread and really enjoyed how you totally improved your mill and with all the information on how each improvement was done--very good job---Dave


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## iron man (Nov 29, 2013)

Thanks Dave As far as the cold rolled it is hard enough the way it is the most I have entered into the new area is only a couple of inches so far on stuff I have machined I have found a place I can purchase small quantity of cast iron I could make a new dove tail out of that but I doubt I will. On these small mills you can do very accurate work but since you dont have the weight of a big mill all your gibs need to be tighter than normal otherwise your machine gets the shake's on heavy cuts. That is why I moved the lead screw I could not tighten up the gibs to stop any play without the table hanging up it all works fine now and I learned a great deal working on it to boot.


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## iron man (Nov 29, 2013)

Here is a better shot of the block after I cut the shaft off I machined three sides and bondo'ed and painted the rest. Ray

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With more head height I can buy taller toys to play with. Ray

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Here is the aluminum slug I machined and then I squared it up to fit in the tube. Ray

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And with the additional height I am able to cut gears this is something I really wanted to do.. Ray


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## j ferguson (Nov 29, 2013)

Thanks again Ray.  Very helpful.  

It appears that there is nothing notchy about the transition from the original to the new dovetail - which I would think would bespeak a very high level of craftsmanship in a challenging alignment problem - matching geometry and alignment of the extension with that of the existing way.

BTW, whose dividing head is that?


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## iron man (Nov 29, 2013)

Yes there is no differance in transition between the two dove tails... I got this rotory table as a gift I tore it apart changed a bunch of stuff I did not like it works great.

http://www.grizzly.com/products/4-Rotary-Table-w-Indexing/H5940

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Here is the thread. http://www.hobby-machinist.com/show...-H5940-Rotary-Table-rebuild?p=99640#post99640


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## j ferguson (Nov 30, 2013)

Hi Ray,
never mind about the dividing head/rotary table.  I found your other thread.  There certainly is a lot of useful stuff in this site.  Thanks for taking the time to share your efforts with us.

john

Hah, I see our notes passed in the mail.  Now we're playing from the same charts


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## j ferguson (Jun 23, 2014)

Hi Ray,
Have you continued to use this mill since the very impressive upgrades?  If so, can you share some of its uses with us?  And regretting that I didn't ask earlier, what did you cut the dovetail on?

best regards,

John


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## iron man (Jun 23, 2014)

Thanks for the reply, Yes I use this mill all the time I have modified it since again by making a longer nut for the table and new lead screw. The extra room really is nice to have the dove tail was cut on an angled table I should have bought a piece of cast iron maybe in the future. If anyone buys any of these Asian mills I would recommend tearing it down and re-assembling it. I found alot of parts either adjusted wrong or assembled wrong check them out carefully. Ray


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## iron man (Jun 23, 2014)

Here are some of the projects I have done on this mill it works just like the big boys.



A new beefier compound for my Atlas 10 inch lathe


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## drs23 (Jun 23, 2014)

Great looking work!


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## iron man (Jun 23, 2014)

A new upper slide that is longer and beefier for the same lathe

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End result.

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End result painted

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I also made a new lower slide longer beefier I made this out of a piece of a man hole cover.

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Here it is completed all work real well. It did not generate a lot of interest I suppose because it takes away from the originalty of the lathe even though it made the lathe much better and more accurate. I also have made gears for this lathe on this mill a new lead screw which required 4' of keyway and a QCTP that worked out really nice all done on this little mill. It may have been made in China but it was redesigned in America..


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## drs23 (Jun 23, 2014)

Nothing could be further from the truth! It peaked my intrest!

Again, great job. Cudos to you!


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## iron man (Jun 23, 2014)

Thank you for the nice comment...The acme nut to the right is the stock one i left it there the brass one is the one I fabricated it is almost 3 inches long. there was plenty of room so why not. The table is much more stable under heavy cuts. Ray




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 Here is the start of the first gear I cut.

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 And here is the final product I just wanted to show that if setup right and dumb designs are fixed these little mills can perform very nice. Dont get me wrong I have seen and have modified some poor american built mill and lathe designs this just shows what can be done to make them last longer and perform better. Thanks for lookin.. Ray


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