Adding accessories to your milling machine

[Modeler12]

I have a mill made by Little Machine Shop. It is very similar to others such as those offered by Micro Mark, Harbor Freight and Grizzly, and - perhaps not in the same class - the Proxxon FF230. But just the same:  they all have one thing in common: they use metric threads and  that can cause some problems when interchanging accessories with those made on the basis of the US standard threads (for example Sherline).

 

I wanted a rotary table for my mill:

After looking at the various options offered by Grizzly (their ‘two inch self-centering vise’), and the rotary table sold by Micro Mark at a much higher price, I went with the 4 inch rotary table and tilting table made by Sherline.  The rotary table is a high quality tool and the tilting table is ok, but nothing fancy. However, the combination of the two gives me a lot of possible machining options.

 

I need to use metric bolts and T-nuts to hold the tilting table to my mill bed. But since the holes in the tilting base are US standard and don’t align with the mill table slots, I had to drill new holes in the tilting table base so it would. The four new holes are clearance holes for 6 mm cap screws and are spaced 1.78 inches apart.

The rotary table is designed to clamp to the tilting table, so now I can use it without having to make new adapters to mount it to my mill table. So, far so good.

 

How about chucks for the rotary table. You can buy them from Sherline, but I also have a mini lathe that has a three and a four jaw chuck. Again they are metric and that is where the rub lies. I don’t use the four jaw chuck very often and decided to make an adapter plate that would allow me to bolt the chuck to the rotary table. I used a ¼ inch thick aluminum plate and drilled the holes as shown in the drawing below.
 

 

The countersunk holes are for the chuck and the slots are for the tilting table and rotary table mounts.

The reason for the slots is that the hole-pattern in the Sherline table is all screwy and not spaced uniformly across the base plate. The two threaded holes used for the brackets to the rotary table could have been moved to 1.29 inches from center (the same as those to the right) instead of the 1.16 inch as it appears now.
However, by having the slots, I can mount this new plate on the rotary table as well as the tilting table. 
 

Here are some possibilities:

·         Use the rotary table and tilting table for a wide range of operations without a chuck.

            

·         Mount the rotary table and tilting table along with one of the two chucks (three or four jaws). This is where the adapter plate comes into the picture.

           

·         Use the tilting table with a piece of plywood to drill holes or mill small parts at an angle (wood only).

·         To machine horizontal slots in shafts, spars or other parts I can take the tilting table (with chuck mounted) and tilt it to 90 degrees. Sherline makes a tailstock for their mill to do just that (it mounts on their mill bed, not mine). I like to keep my 4 inch vise where it is and I think I can make an adapter to serve as the ‘tailstock’ using wood. Besides, how often would I need that?

 

Making the adapter plate was a nice metal working project and I got to use the rotary table for the first time. It worked great.

[mtaylor]

Looks great, Jay.  You're giving me ideas... I have a rotary table but just havent' figured out a satisfactory way of mounting it. 

[Modeler12]

Looks great, Jay.  You're giving me ideas... I have a rotary table but just havent' figured out a satisfactory way of mounting it. 

That's one reason I got the tilting table ($110). It makes it easier to mount the rotary table to the mill bed and also serves me well for milling parts at a bevel or some other angle.

[shiloh]

Looks good, now all you need is a dividing plate or two for that rotory table. Probably already have that planned.

jud

[Modeler12]

Looks good, now all you need is a dividing plate or two for that rotory table. Probably already have that planned.

jud

Good idea, but I don't know if Sherline makes the dividing plates (and their conversion to the rotary table). Or am I missing something?

 

On hind sight, Little Machine Shop makes a rotary table and offers a couple dividing plates that might come in handy.

But again, how often do you need the kind of accuracy a dividing plate has in our modeling? Hand cranking to a scribed mark is still ok for me .

 

The main question I still have is: to stay 'metric' or be able to convert? 

Of course that has been a major political problem here in the US. It is a bit like using the 'chip' in credit cards (that is finally being used by many merchants and customers here). The US is a bit slow along those lines!!!

 

There are many good stories about that, I am sure.

[Mahuna]

Hi Jay

 

Sherline does make an Indexing Attachment that is used for dividing.

 

http://www.sherline.com/3200inst.pdf

 

I have it, but haven't used it yet (when I bought my used Sherline setup it contained almost every attachment Sherline makes for the mill and the lathe).

[Modeler12]

Hi Jay

 

Sherline does make an Indexing Attachment that is used for dividing.

 

http://www.sherline.com/3200inst.pdf

 

I have it, but haven't used it yet (when I bought my used Sherline setup it contained almost every attachment Sherline makes for the mill and the lathe).

Thanks for the link, Frank. At this time I don't want to spend another $200 for the Sherline attachment. At first glance it seems a bit complicated compared with the normal dividing plates. But until I really need to do a lot of that kind of machining, I will hold off.

[Mahuna]

They also make a set of Indexing Blocks - $60

 

http://www.sherline.com/2045inst.pdf

[mtaylor]

Rats... I need to find a "shorter" chuck for mine...   <checks HMS Visa.... hmm.... repairs still underway>  Using the table without the chuck has been problematical at best but your way is genius.  

[Modeler12]

Indexing blocks are a clever way to go. Turning the vise sideways is also a nice idea that may come in handy when milling tall parts that need to be clamped in the vise.

Until I really get used to working with my mill a lot more, I think the rotary table and its very nice angular graduations will suffice for indexing.

[Modeler12]

I decided to experiment with my new, modified toy and see how things worked out. Good thing; I found a couple hick-ups.

Below you can see the small wooden block mounted on the rotary table using the four jaw chuck. I cut some grooves horizontally and then tilted the table as you can see in the pictures.

A couple problems:

1. Mounting the chuck directly on the tilting table (using the adapter plate) is tricky because of the graduated angle pieces. The unit also sits too low so that I cannot tighten the jaws with the wrench provided. Mounting it on the rotary table took care of that.

2. The cap screws in the far right bottom corner hold the table to the mill. But I did not leave enough clearance when tilting the table. I need to take the unit apart and cut away some more metal.

3. My intent is to leave the chuck mounted on the adapter plate. However, as you can see, the cap screws that hold the plate to the rotary table interfere with the chuck jaws. Now I need to mount the chuck first with the jaws closed and then mount the work piece  I should have made the holes in the adapter plate rotated -let's say- 30 degrees off center. That way I could close the jaws any time before or after. I can remedy this by making new slots or new countersunk holes in the adapter plate.