Thread: 6b4

Hi Rod,

Nice build, I found this thread pretty interesting.

What machine did you machine the ally on? And what is a machine like the one in this thread capable of?? #

Hi slhouetteV8,
I cut the plates on Morphy (see photo) which I built 5 years ago and has been my workhorse since. I may have cut some of the smaller plate on another of my machines but can't remember as this build is two years old - slack aren't I.

This machine will have a cutting envelope of 600mm by 400mm and depth of cut around 130mm. Smaller machines can be more rigid than larger ones so I would expect it to cut acrylics through to brass. I have cut 40mm thick ally with these machines.

Ok some progress.
I pulled all the ballscrew end bearing blocks apart and greased them and adjusted the fit of the bearing and seals.
As I had changed the ballscrews from the original set I needed to redrill the side plates or shorten the ballscrews on the lathe. I decided to redrill the plates so I needed to make a jig/fixture to hold the plates and reference them to zero on the machine. The easiest way is to make a pocket out of some scrap and slip the plates in. See photos.
Note how I overcome the radius of the cutter in internal corners and the square cutout at the front so I can lever the plates out once the job is finished. That spoilboard needs changing on the machine.

On another issue I got this 4th axis and tailstock assembly recently and will use it on this machine. I consider it to be good quality and having a 100mm 4 jaw self centering chuck it is good for both round and square stock. Being a self centering chuck there is not the need to dial your job in like a 4 jaw independent chuck.

As it is 42 degrees I have come inside to the aircon and may venture out later depending on how long I nod off for.

You've built some awesome machines Rod. After reading this and a handful of your other build threads I've decided to have a go at building one myself. You've inspired me!


I see in your older builds you used fabricated or welded steel bases. How do the aluminum extrusion bases compare to the steel?


Im looking at something around the 900 x 600 size or smaller and my main concern is that I can machine ally. Do you face those plates or just cut the shape?

Originally Posted by slhouetteV8

After reading this and a handful of your other build threads I've decided to have a go at building one myself. You've inspired me!

The main reason for posting here is to encourage others to have a go.

The plates are not faced and only the edges cut to shape. The only reason to go steel is to keep costs down however there is a lot more work in steel.
I only weld the framework for the trolley and never weld the machine itself. The ally extrusion is very convenient and can be ordered cut to size - very exact tolerance on the cuts so it is like assembling mechano (might be showing my age by quoting mechano).

Ok I have been plodding along and have finished mounting the two X axis and the Y axis ballscrews. I'll work on the Z axis tomorrow and then the gantry sides as all the offsets will be know by then. Photo is crappy due to night time flash and the machine looks strange as the gantry needs lifting up about 100mm but proof that something is happening after such a long break.

Starting to look pretty good Rod, love watching your work in progress, have learned a lot from that.

One question, how is the belt on the gantry stepper motor in the above pic tensioned?

Originally Posted by Big Shed

Starting to look pretty good Rod, love watching your work in progress

Calling it a 'Work In Progress' is a little over the top. Compared to the comparatively speedy evolution of humanity from the trees and caves of paleontological history, the progress on this build is woeful.

Hi Fred,
Easiest way to show that is by posting a picture of the drawing. The left side is the motor mount and the right is the base it attaches to. The base can be adjusted left and right to align the pulleys and the motor can slide in and out to tension the belt.

Originally Posted by Bob Willson

Calling it a 'Work In Progress' is a little over the top. Compared to the comparatively speedy evolution of humanity from the tress and caves of paleontological history, the progress on this build is woeful.

Bob,
It is too early in the day to think of a witty response to that so I'll give you that one - it has been a very long build.

Almost finished the Z axis. It is built on a THK KR 33 actuator that has two trucks and 140mm of travel. I like the actuators as they have four bearing surfaces so are strong in vertical movement as well a rotary (twisting) resistance. The 140mm travel will be perfect for the 4th axis I showed in an earlier post.

First job was to make an adapter plate for the Nema23 motor and that is direct coupled with a helical coupling to the ballscrew of the actuator. The spindle mounts I cut a while back and have a laser cross-hair incorporated in the bottom mount. The spindle is 1.5kw air cooled. The backing plate is 12mm ally plate and will have skirts fitted to the sides to strengthen it and provide protection from ingress of swarf to the actuator.
The shiny bit at the top of the backing plate is for cable management and it's main purpose is to hold the spindle cable as well as provide routing of air pump and other wiring to that area. I polished a few bits on this assembly because the day got hot and I felt like wasting a bit of time until is was comfortable to work again.

I have an important visitor coming tomorrow for a chin wag so progress will be delayed.

Z axis is finished as is the gantry carriage for Z axis. The gantry sides will lift the gantry 140mm higher to allow full travel. Not much more to say so I'll let the pictures show the progress.

Looking great Rod.

Where do you get your linear bearings from? How much do they cost you?

As the machine has been idle for a couple of years I can't remember where I sourced the THK20 rails. The NSK15 I got from a pallet sale of them from the USA about four to five years ago. Buying from USA is very expensive for freight now. What I do is plan well ahead and watch ebay until something suitable comes along at the right price.

This one looks much sturdier than some of your others. I've been scouring the web and come across the same dozen or so pages a dozen or so times and read heaps of builds, I think your builds are some of the best I've come across. I particularly like this one because it's a small heavy duty version. I seem to have come to the same conclusions as you, the uprights for z axis travel that most people use are a weak point, forming a torsion box in the gantry that bears directly on the slides seems like a much stronger design.#