Thursday, July 19, 2012

Sherline - Digital Display

Both of my hand cranked machines are located next each other. When I added the digital readouts I decided that I would save the money and use a single readout.

So I just leave the wires clearly marked nearby and plug in whichever I'm using at the time. Mainly it keeps valuable bench top space in order.

Of course the Zm (Z position mill) display never has to come out and remains plugged in all the time. I find backlash to be a constant challenge on the Sherline machines and so just resign myself to constant fiddling and compensating.

Sherline Lathe - Tool Caddy

There are the few set up pieces I need to cover 90% of the jobs on the lathe and the mill.
My two hand cranked machines are located right next to each other.

I drilled holes into a plastic block for the:
  1. 3 jaw chuck bars
  2. A drill chuck key
  3. Large allen wrench
  4. Small allen wrench
  5. Edge finder
With these six pieces at my fingertips I can really fly!

This is truly a huge improvement with my left hand I can pick up both of the 3 jaw chuck bars at once and before the head stops spinning I am ready to release the work piece.

The T handle Allen wrench is a must for swapping out the three different tool bit holders quickly, I leave the tall T nut in the cross slide and the bolt in each of the tool holders and spin the T handle to run the bolt up and down.

Wednesday, July 18, 2012

Sherline CNC Mill - Biscuit Jointer Hold-down Groove

Its all about getting the workpiece onto the cross slide ASAP.

I often find that I simply want to mount the blank directly to the cross slide and instead of using the tall clamps and stepped riser blocks (which are a pain) I prefer to use the little clamps. Cutting a groove in the ends of the workpiece can be time consuming but not with this method.

The standard method is to epoxy the blank to a piece of plywood but that takes time and money. 

I set up my biscuit joiner to the proper depth (3/8ths) and in two seconds I have a groove into my blank.

In this case it went thru nylon with no effort.

This an example of "cross-pollination" from my woodworking experience. The biscuit joiner is a little portable End Mill that has excellent accuracy, repeatability and adjustment.

Tuesday, July 17, 2012

Sherline Mill - Quick Set - Up Machine Vice

The machine vice is of course the number one tool for my hand crank mill.

 I made a set of plates that can mount onto any of three sides and hang down below the level of the cross-slide. The result is that I can hold the vise up against the side of the cross-slide and tighten the clamps in seconds.

Is this cheating? I think not; it is accurate enough for most work, possibly as accurate as these little machines can be. 

Sherline Mill - Y Axis Extension

To start working larger pieces on my CNC Sherline I bought an 18" cross slide and lead screw. During installation I realized that the Y axis lead screw was a lot longer than it needed to be and thought of this modification.

The Z axis block is bolted to the bed plate with two screws, I decided to move the Z axis block back and use the rear fastener as the front. I then made this extension out of 3/8 aluminum angle. When I bolted it down for the final time I added 5 minute epoxy to the surfaces for added stiffness. I've been running like this for about two years. I use paper to shim the vertical axis ways into perpendicularity.

Because the Y axis lead screw nut is at the front cross slide saddle the rest of the lead screw is unused. Best of all this is a one morning project and you get about 2.0" extra Y travel for free!

As you can see the lead screw is plenty long enough to stay comfortably in the anti backlash assembly. 

This guy is on to something Laser Alignment for the Sherline Mill  *I*

Sherline - Tool Caddy

Not so much an invention but I am thrilled when something works better than expected.

Because I have my machines in two different locations I needed to have a way to bring all of the bits & pieces back & forth.

I added a robust wire handle across the top. It is great to have everything in one place; just spin it around to find what you need.

I looked around at estate sales until I found an extra  box wrench that had both 9/16 & 1/2 on it so I have only one wrench to keep track of.

Spin-O-Tray Rotating Desktop Organizer

Monday, July 16, 2012

Sherline Mill - Mechanical Center Finder

My motto is "do the easy stuff first" so I try make things easy.

Because I use my CNC for all sorts of millings from 2d to 3d, large & small I have adopted the "start at the center of the blank" rule. We know we are going to have extra stock all around so finding the work piece center is good at plus or minus ten all day.

I took a piece of 13/32 OD brass tube and added a solid brass end to it and turned it to a point.

I mark the center of my material, place it on the cross-slide, drop the pointer down, and move things around until I get the position I like, and lastly clamp the work piece down.This alleviates a lot of effort and anguish trying to bump the axis' into position.

Note the little arrows I put on the bed, with these I can get back to the center of the travel (with a few thousandth) and again for CNC work that starts in the middle of an oversize blank

This thing works great, it would be better made of steel but the off the shelf brass tube is a home run.

Of course it's not dead center; it creates a small circle if you spin it.  I will post center finder 2 ASAP.

Ultimately someone needs to invent an optical piece that drops into the hollow shaft; that would be cool!