Outboard turning on MC-900

[AdamJGS]

Hi guys,

I am scratching my head trying to figure out the tool-rest extension arm that came with my lathe. I would assume that it is meant for outboard turning, but I can't set it up in a way that gives me any greater swing or easier access to the work.

I have attached a few photos to help illustrate. On the arm, where the tool rest hole is, one corner is chamfered and I would assume that this is the part that is supposed to be towards the work. I have tried every position available on the lathe head (normal, plus 45, 90, 135 and 180 degrees clockwise only), but I can't make this chamfered corner face any direction that would be useful. Considering the extra expense to make this piece and the bed extension to the left of the lathe head, I am expecting there to be something I am missing.

I cannot see any way to reverse the spindle direction, nor can head be locked in a position that is anti-clockwise from the normal position.

Any help would be greatly appreciated. Also attached is a photo of a little (~5") jarrah burl bowl, my first effort since getting back to the lathe after 5 years.


Thanks,

Adam

[AdamJGS]

I have the term 'outboard' confused... What I mean is 'with the head rotated'.

[Skew ChiDAMN!!]

AFAIK, the way it's pictured is the way it's used. [shrug] It's enough (barely) to handle diameters slightly over the normal bed-swing, but as ya alrady know is useless for anything of any really greater size.

Even if it could handle larger diameters, it'd be pretty useless 'cos the extension allows extra flex and thus more prone to causing chatter. This can be avoided by bolting a leg under the tool-rest, but if you're going to do that you may as well make a heavy tripod for it instead... one that's seperate to the lathe and can be moved to where you want it!

Actually, I find the whole banjo assembly a pain. In normal turning if I remove the extension then the bottom of the tool-rest spindle is just barely held by the grub screw when at working height. If I leave the extension in so that the toolrest mounts securely, I get the chatter problem when doing deep or heavy turning.

I modified mine, but it bloody well annoyed me that I had to in the first place. :(

[Utuk_Xul]

You have the right idea about it's use. And you WILL get lots of chatter when hollowing with the thing :( but it does come in handy. Just be careful you don't get a nasty catch while using the extension. It can snap in half.

[hughie]

Hi Adam, I had the same problem and found that at having the chuck at 90' rather than at 45' or so as you have gives you a bit more. But in the end I made another extension arm about the same length and fitted a piece of steam pipe [1 1/4 dia ] to it down to the floor.This enabled me to turn about 360 plus diameter very easily. Would have made the arm a bit longer but thatwas all I had on hand.
I'll send some pics when I find the digi camera, this will show easy it is to set up.

Hughie

[AdamJGS]

Thanks for your responses! Glad I wasn't missing something, but then maybe I wish that I was...

[Utuk_Xul]

Does yours have the 3/4hp motor? You would be pushing the limits of the thing I would think. Or did you upgrade the motor?

[gatiep]

What Skewie said is spot on. However in your pictures you are setting the toolrest right accross the 'face' that you are turning. Remember that the toolrest need only extend a little more than the left of the centre of the face. The MC style banjo/banjo extention/toolrest was not intended for doing "Big" bowls but rather to enable the turner to swivel the head and hollow out the bowl headon instead of bending/leaning over the bed when hollowing. This makes for less strain on the back plus it makes it easier to see where the tool is cutting ( for those that do not observe the cutting process on the opposite side of the bowl ).
The extension arm makes for a rather 'flimsy' support inducing chatter when heavy cuts are made plus it raises the minimum height setting of the toolrest too high. Having said that, I have not seen a better commercial available system on a lathe costing around $379. I have found Vicmarc's outrigger as is supplied with the VL-175 etc to be as near to 'perfect' as I think possible without making an external dedicated toolrest support.

Definately remove the extension when turning over the bed as again it just raises the minimum toolrest height too much and can induce unnecessary chatter.