FAQ - tool rest info for the G0766

[Roger Chandler]

I have had a number of private messages and emails regarding the Robust and other aftermarket toolrests for the G0766 lathe. Thought it would be prudent to place some information here for viewers as a reference on the matter.

#1 - banjo hole- I recommend highly that all G0766 owners bore out the 25mm hole to 1"....a difference of .004" and can easily be done using a twist drill bit and some oil to lubricate the cut. This will allow for many standard issue aftermarket accessories to be used, like coring rigs, threading jigs and others that come standard with 1" posts.

#2 - As related to Robust rests for the G0766 - I got mine custom made to 8.75" total height [from bottom of post to top rail, where the tool actually touches the rest] but I have heard that there is plenty of post in the newer banjo to allow a 8.5" post, total height, but I have not personally verified that. That being said, Robust can make 25mm posts, but if you keep the 25mm hole, you limit the other accessories as I mentioned above, and it is such an easy modification that I don't know why anyone would not want to do it.

#3 - Other make tool rests [like round bar rests] can also be used, not just the Robust......just make sure total height is 8.5 to 8.75 inches, top to bottom.

#4- I also had a question or two about banjo replacement - If you got a G0766 after about September 2015, then you likely have the updated banjo. Some were thinking they needed to replace that and wanted to know which Oneway banjo to get.........with the updated banjo there is no need for a Oneway. Although I did get the Oneway because I was not willing to wait on Grizzly's upgrade, I now use the updated banjo from Grizzly exclusively. I am happy with it. If you are not sure you have the updated banjo, just measure the base........if it is 17" long at the base, you have the updated version. Replacements were shipped by Grizzly to all the owners who previously had the smaller banjo along with the appropriate hardware to make the conversion.

Hope this information helps all those who are considering aftermarket rests for your G0766.

[Bill Boehme]

........ #1 - banjo hole- I recommend highly that all G0766 owners bore out the 25mm hole to 1"....a difference of .004" ....

How about a difference of 0.016" (to the nearest thousandth)? Your recommended method seems risky from a personal injury point of view if the drill grabs.

[Roger Chandler]

How about a difference of 0.016" (to the nearest thousandth)? Your recommended method seems risky from a personal injury point of view if the drill grabs.

Perhaps I should have included the advice/disclaimer to use a drill press with the banjo clamped down if possible. I did the same thing on my G0698 lathe with a hand drill. If one is using that method, use cutting oil, and have the bit spinning slowly as the bit enters slowly into the top of the hole....one can clamp the banjo to the lathe ways for that. Of course everyone needs to use their own best judgment and safety practices, but this is such a simple fix. A grabby drill could concievably break a wrist, so be careful out there everyone!

Sorry, that I did not actually take the time to do the mm conversion, and was just going by what I had read from someone on the GGMG, if I recall correctly, but I did take the time to do the conversion as of this post, and it basically amounts to enlarging the hole by 1/64"

[Ralph Lindberg]

How about a difference of 0.016" (to the nearest thousandth)? Your recommended method seems risky from a personal injury point of view if the drill grabs.

I used a brake-hone on both the Nova and Grizzly
It takes longer then a drill, but I think it's safer

[Roger Chandler]

I used a brake-hone on both the Nova and Grizzly
It takes longer then a drill, but I think it's safer

It is indeed with a hand drill, but with a drill press and the banjo clamped to the drill press table, the bit spinning at about 300 rpm and cutting oil to lubricate, it is a safe proceedure, if one enters the bit slowly and has the bit centered on the hole. Common sense must rule!

[Brice Rogers]

I drilled mine on a drill press and didn't have any problems. I think that the most important thing is to have the drill bit perfectly centered over the existing hole and have the banjo firmly clamped to the drill press table. Otherwise you may end up with a triangular hole. I took my time drilling and cleared the small amount of debris being produced several times so that it wouldn't increase friction. I believe that I started the drilling operation with a "peck" or two to get the hole started as straight as possible.

I used a lubricant, but I really didn't need to. If you google it, you'll find that most machinists drill cast iron dry because the high carbon content of the cast iron acts as a natural lubricant. Steel has a low carbon content and is obviously different.

My drill bit bored a slightly undersized hole. That isn't terribly surprising given that I was only removing 0.008 " all the way around the drill (0.016 total). Just the outer edges of the drill were cutting and it was acting more like a reamer than a normal drill. So I ended up taking a wooden dowel, turned one end to 1/2" to chuck up in a hand drill, and slotted the dowel to hold some sandpaper. Then I ended up taking the final few thousandths off in the grinding operation.

BTW, if you own a mill or have a friend who owns a mill, that would be an ideal machine to bore out the banjo.

[Dennis Collier]

Boring the banjo on a drill press is completely safe.

I can confirm that the 8 1/2" total height tool rests work fine. The Robust "extra Long" post is what is needed. You have to call them as that length isn't listed on the website yet. They don't charge anything extra for the longer posts.

[Roger Chandler]

Boring the banjo on a drill press is completely safe.

I can confirm that the 8 1/2" total height tool rests work fine. The Robust "extra Long" post is what is needed. You have to call them as that length isn't listed on the website yet. They don't charge anything extra for the longer posts.

I am glad you distinquished between the "extra long" posts and the "long" posts. My former G0698 used the long posts and they were 7.25" total height, which did not leave enough post in the banjo hole with the updated banjo Grizzly made.
Thanks for the confirmation!