Good morning!
If you wonder why I haven't been around the past 2 weeks or so, this project here is the answer... Not strictly audio related, but it will be used to make audio related projects so hence I guess the rules can be flexed just a bit?
Some of you may know that I purchased Gert's (Gearslave) old CNC router a year or two ago. It is a fantastic machine and did some really good work (including cutting all the Viviere face plates, etc), however with me being the way I am (not always right in the head) I have always wanted to do a couple of things to it. The push finally came about 3 weeks ago and so this is the build thread in brief.
What I wanted to achieve is accuracy and rigidity. I don't mind giving up speed in order to achieve those two objectives. Some guys think it's awesome to move the gantry at 12 meters per minute. Personally that doesn't interest me too much - I want the gantry to move correctly. If that means I can only get 3m per minute then that's good by me.
So I had a number of choices:
1. Try to upgrade my existing machine to the point where I would be happy. That would mean reinforcing most of the members, and completely rebuilding certain parts of the machine to gain the additional rigidity and stiffness.
2. Build a new machine.
The obvious choice would be #1 because in theory it could be done in far less time and for a significantly lower amount of money. Initially I was drawn to doing this and spent a good amount of time looking, measuring and thinking. However the more I thought about it, the more it didn't truly make sense to follow this path. I started to realize that the only real way to achieve what I wanted was to redesign parts of the machine. At some point I guess we redesign so many things that in reality you are building a new machine, hence I then decided to rather follow choice #2.
If you are building a new machine you have the opportunity to make it bigger (or smaller) as needed. In this case I am going slightly larger but not much. The bed size now measures 1.6m long x 1.1m wide. Not all of that will be usable but let's see how that works out.
Firstly I needed to find some aluminium sections to work with. The easy way out is to use those slotted extrusions they sell which allow the use of T-nuts and they come in different sizes. This is a quick web image of what I am talking about:
^^^ This type of thing seems to be used by nearly everyone building a CNC machine. My own machine (Gert's old machine) is also built from it, so I guess it must be reasonably good stuff if everyone is using it. It sure makes life much easier to use this stuff.
I took a good look at some of these sections and came to the conclusion that whilst it may be good enough for most, it would not give me what I needed from my machine therefore I would need to find something with a bit more beef.
Now: I can weld if I need to save my life but I am not what anyone would call even mediocre. My motto when it comes to welding is simply this: If you can't run a good weld then you must be able to run a great grind
Not that we want to use welding anyway because welding means bent, twisted, warped and otherwise undesirable sections where what I want here is flat, square and true. In my mind that means bonding and bolting, hence that is the construction method used throughout.
Steel can be difficult to work with (I don't have any steel working machines) so this would be made from aluminium sections because most of my woodworking tools could be adapted / used on aluminium.
Next thing was to try and find some heavy aluminium sections. Now I know that we are producing this stuff (the Hulamin website shows all the standard extrusions they make), but alas - it is nearly impossible to find some of these heavy structural sections. I must have phoned 10 different places and none of them keep stock. All of them are happy to get it for me, but that would mean minimum order quantities to the extent that I could not take that path.
The only other option then was to find some suitable bits and bond pieces together to make up the heavy sections I want. This has taken a huge amount of time however seeing as it is really the only option there is no crying about it :-X
So then - this is the pile of aluminium extrusions I bought. Not included in this picture is a couple of plates with the main one measuring 1.8m x 650mm x 12mm and some smaller 6mm plates and 3mm plates:
Here I started laying out the first section which is used for the long support rail on the bed:
The angle piece is 150mm x 50mm x 6mm and the square tube is 38mm x 38mm x 3.1mm:
And this is it all bonded together:
...more pics and things to follow.
As always, feel free to comment / share / question!
Kind Regards,
Ian.
If you wonder why I haven't been around the past 2 weeks or so, this project here is the answer... Not strictly audio related, but it will be used to make audio related projects so hence I guess the rules can be flexed just a bit?
Some of you may know that I purchased Gert's (Gearslave) old CNC router a year or two ago. It is a fantastic machine and did some really good work (including cutting all the Viviere face plates, etc), however with me being the way I am (not always right in the head) I have always wanted to do a couple of things to it. The push finally came about 3 weeks ago and so this is the build thread in brief.
What I wanted to achieve is accuracy and rigidity. I don't mind giving up speed in order to achieve those two objectives. Some guys think it's awesome to move the gantry at 12 meters per minute. Personally that doesn't interest me too much - I want the gantry to move correctly. If that means I can only get 3m per minute then that's good by me.
So I had a number of choices:
1. Try to upgrade my existing machine to the point where I would be happy. That would mean reinforcing most of the members, and completely rebuilding certain parts of the machine to gain the additional rigidity and stiffness.
2. Build a new machine.
The obvious choice would be #1 because in theory it could be done in far less time and for a significantly lower amount of money. Initially I was drawn to doing this and spent a good amount of time looking, measuring and thinking. However the more I thought about it, the more it didn't truly make sense to follow this path. I started to realize that the only real way to achieve what I wanted was to redesign parts of the machine. At some point I guess we redesign so many things that in reality you are building a new machine, hence I then decided to rather follow choice #2.
If you are building a new machine you have the opportunity to make it bigger (or smaller) as needed. In this case I am going slightly larger but not much. The bed size now measures 1.6m long x 1.1m wide. Not all of that will be usable but let's see how that works out.
Firstly I needed to find some aluminium sections to work with. The easy way out is to use those slotted extrusions they sell which allow the use of T-nuts and they come in different sizes. This is a quick web image of what I am talking about:
^^^ This type of thing seems to be used by nearly everyone building a CNC machine. My own machine (Gert's old machine) is also built from it, so I guess it must be reasonably good stuff if everyone is using it. It sure makes life much easier to use this stuff.
I took a good look at some of these sections and came to the conclusion that whilst it may be good enough for most, it would not give me what I needed from my machine therefore I would need to find something with a bit more beef.
Now: I can weld if I need to save my life but I am not what anyone would call even mediocre. My motto when it comes to welding is simply this: If you can't run a good weld then you must be able to run a great grind
Not that we want to use welding anyway because welding means bent, twisted, warped and otherwise undesirable sections where what I want here is flat, square and true. In my mind that means bonding and bolting, hence that is the construction method used throughout. Steel can be difficult to work with (I don't have any steel working machines) so this would be made from aluminium sections because most of my woodworking tools could be adapted / used on aluminium.
Next thing was to try and find some heavy aluminium sections. Now I know that we are producing this stuff (the Hulamin website shows all the standard extrusions they make), but alas - it is nearly impossible to find some of these heavy structural sections. I must have phoned 10 different places and none of them keep stock. All of them are happy to get it for me, but that would mean minimum order quantities to the extent that I could not take that path.
The only other option then was to find some suitable bits and bond pieces together to make up the heavy sections I want. This has taken a huge amount of time however seeing as it is really the only option there is no crying about it :-X
So then - this is the pile of aluminium extrusions I bought. Not included in this picture is a couple of plates with the main one measuring 1.8m x 650mm x 12mm and some smaller 6mm plates and 3mm plates:
Here I started laying out the first section which is used for the long support rail on the bed:
The angle piece is 150mm x 50mm x 6mm and the square tube is 38mm x 38mm x 3.1mm:
And this is it all bonded together:
...more pics and things to follow.
As always, feel free to comment / share / question!
Kind Regards,
Ian.
