RE: [CAD_CAM_EDM_DRO] Annoying Newbie Questions

Some of the materials you are wanting to machine are pretty tough stuff.
Titanium is particularly hard to cut as it work hardens just looking at it.
The normal technique is to use a slow feed and a heavy cut so that you are
essentially cutting under the hardened surface. I think you could pull it
off if you are looking to turn a ti shaft, but if you are looking to mill it
I don't think the Shoptask will be up to the task (or most anything else
under a 3 or so hp mill). I am not up on Inconel, but the little I have
heard is that it is easier to grind than to mill. The other materials are
all very doable on the Shoptask.

Not to dash your hopes, but I would suggest that you pick out a few smaller
projects than a turbine to start with. Turbines have quite a few very
critical tolerances and the casting you have to work with are relatively
expensive if you mess up. This is not to say that the Shoptask is not up to
holding the tolerance you need, but you are definitely in the range where
machining knowledge and skill will have a big effect on your results.

The Shoptask is a nice machine for the money and makes a good CNC platform.
It is VERY easy to convert as it was designed with CNC in mind. You will
need to rework the Z axis to get the slop out of it, but even that is
straight forward.

Tim
[Denver, CO]

> Hi All,
>
> I'm a "wanna-be" hobby machinist who is looking to buy a
> ShopTask, once I'm
> settled in a new house. I've been doing software development all
> my life but
> always had an itch for mechanical creations. I've been reading through the
> Shoptask Delphi List, as well as the archives of this list, but still have
> some questions. It seems that machining is similar to software development
> in that a project can lead to many sub-projects and sometimes you
> feel like
> your going backwards(spending time to build tools to be able to build the
> core project). I'm fine with that :-]
>
> Probably against some of your recommendations, I would like to jump into a
> CNC setup since I'm already a computer "propeller-head".
>
> My initial project would be a miniature turbojet since R/C Jets
> is one of my
> hobbies. I've read about the shortcomings/price of the ShopTask CNC add-on
> and associated software and I'm still evaluating going the route of Tim
> Goldstein with the custom CNC setup. Looking at the following link, would
> it be possible to handle such a project with the ShopTask Eldorado Package
> "out-of-the-box"? http://www.wren-turbines.com/MW54parts.htm
>
> Some of the materials I would be machining with would be Aluminum, 4340
> steel, Inconel, Stainless Steel, Titanium.
>
> Thanks and sorry for the long, newbie post.
>
> Erik Nielsen
>
> FAQ: http://www.ktmarketing.com/faq.html