Newbie question: how to get tool to the right height?

tmenyc

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With everyone's, particularly MiIkey's, help, I have gotten all my basic tools together and this weekend am doing first turning on my Logan 820. I bought a 3/8" carbide set to get started, but just received the model keystock set to teach myself how to grind my own.
So today, I got the Logan oiled and more cleaned up, and bolted on the quick change holder, and inserted the tool. It's about 3mm too high and I can't see how to adjust height. I'm thinking that the 3mm is the 1/8" difference in using the 3/8" tool rather than 1/4", so are the tool holders different? Do I need to find a tool holder that bolts on lower? I already removed the shims from the under the tool holder.
thanks, Tim
20181201_182146.jpg20181201_182336.jpg
 
Your tooling is to big for the tool holder. Looks like 1/2 or 5/8 tooling? Only way your gonna be able to use those is a qctp. You can take the compound off and mount your 4 way directly to the saddle. 1/4” tooling might be more the right size for what your dealing with.
 
Unfortunately, with the 4 way tool holder that you show, you can't adjust it any lower. The only recourse is to use the 1/4" tooling. You could purchase a quick change tool holder. You will have to measure the distance from the top of your compound to the spindle centerline to determine which one to get.

As a starter, an AXA quick change tool holder is minimum of around 15/1`6" from the compound to the cutting edge of a 1/2" tool and 13/16" for a 3/8" tool. An OXa is smaller and the BXA is larger.
 
What they said! I know you want to play with it right now so there is a way. Turn you tool upside down and shim the tool post up till centered. This way you can at least have some fun while waiting to spend more money. No danger of it un-threading as it is a collet.
 
RJ, I'm assuming the measurement is height? The compound base base is gently sloped. Its center to spindle center = 78mm, 3.1". I don't think I understand the measurement meanings in your response.
B, I'll give that a shot! Interim answers are eagerly accepted, while I learn solutions.

Thanks,
Tim
 
Not at all familiar with your tool post regarding adjustment.

As far as finding the correct height, the easiest way I've found is to put a center into the headstock and then line the tip of the tool up with the point of the center so the points are even.
 
Not this newbie...
Why not? I have never been in a machine shop that did not have dozens of tools that had parts milled or ground away for various reasons, common practice.

If you had to use that tool to turn a small diameter using a live center you will find that the body will hit the center before you reach the finished diameter, do not do this because the center will not enjoy it.
Grind the back of the tool for clearance.

Also that is not an ideal insert shape for aluminum, try a positive rake sharp edged geometry like this, you will be far happier.
 
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Tim, this is from Logan Actuator: http://www.lathe.com/faq/index.html#_Toc95180289

Which size Quick Change toolpost fits this lathe?
3.1.. For Logan 9”, 10” and 11” lathes, the “AXA” or “100” size quick-change toolposts from Aloris and Phase II fit well. For 12” lathes, the “BXA” or “200” size quick-change toolpost will be slightly more sturdy and still fit. The 14” lathes can also use the “BXA” toolpost or the “CXA” or “300” size.
 
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