TOPIC:

While I wanted to cut some aluminium, this was defered to later date due to an issue with Makera Cam and the step i'm trying to work with. I reported the issue and will wait for a resolution.

In the meantime, I decided to give a test ride to the 4th axis...


There is some instruction to follow precisely for the sample, otherwise you may rough cut the chuck. I paid attention when launching the gcode.


One thing to note, it's better to note where is the top side of the stock when using 4th axis, as if there is a power failure, it's probably better to be able to recover that position.
Anyway, after removing the mess after the rough cut here is what we have:


And then we proceed to the tool change and the finishing passes...


And here is the final result :


Overally the relief worked well. That's currently the only type of path supported by Makera Cam with the 4th axis. More may come, but no precision yet on their plans. I'm not fully sure yet what would be the best way to create gears, for examples. I'll have to find out...

The Laser module of the H2D is not thought to have a very heavy use. 
My wife ordered some Aluminium red anodized tags on amazon, and she targets to use them to identify the covers for the poneys (there is two : Smartiz and Majesty, and their requirements in terms of covers are not the same, and there is about a dozen of covers per poney to cover all the seasons and weather). For me it is the occasion to test ride the laser with non Bambu Lab material.
First, I wanted to have an idea of the settings to use. I went to check on Xtool website (there is some parameters indicated for each and every material and type of processus), and it was apparently the same for Anodized aluminium, whatever the color of the material was. That makes it very easy then. In Bambu Suite, I just created a new material based on the black aluminium card material, and uploaded a picture of the material itself, and gave it a different name.
I also designed a small support as it will allow to set and forget the position once I do multiple in a row.

And the result is quite nice (here it is laser filling, I checked the laser line, the result is perfect as well). The jig allows to remove the need for orientation change, and I just have to position the element to mark on the material.

My wife is happy, I explained her how to use Bambu Suite and the H2D for this, and she will be able to do this by herself (as long as the machine is in laser configuration).

The Carvera Air (and it is the same with the Carvera) relies on 1/8 shank bits. A collar is installed on the bit at a defined position to allow the tool changer or rapide tool changer to take the shank properly during tool change. I bought some drill bits on amazon to be able to work with some of my projects, and the default collar of those is not properly placed.


But Makera includes a tool for this... A part is used to remove bit collars. 

It's not very long to remove all the previous bit collars...


And it's fairly easy to install the makera bit collars



I also installed an air pump (not without some adjustment as it was delivered with UK plug) next to the machine to feed the air assist, and that was the last thing absolutely required to work with metals...

I'm straight away saying one key thing : "Failing is learning"! This will take full sense later on this post, but it is key to understand my mindset working on those things...

Air assist is in place, it is time to experiment with Aluminium. Step down is 0.2mm, and harder material can be tackled with lower step down...


Had the material set, the paths defined, and the tools sorted


There is only thing to do which is to click run, and change tools when needed...








Next a bit of cleaning, because it's required (don't tell my wife I know how to use a vacuum, please )...




The finish is quite good... Now, I only dealt with a single face... Next is the bottom and the top of the parts where I need to drill and add threads
I first considered a printed part to hold the part...
But I was not really happy, so I decided to use the vice and the plate prepared in the fablab.

That said, I did not plan to use the vice this way, and when working out the lining of the vice anchor point, I did not took that point into account, so I have to input an offset to the work origin. I put 4 initially and it was a small mistake.

I over compensate the mistake on the second part, so the pod should be still centered, but I may have to review the rear part (or redo this parts better). I don't know yet, we'll see...


Anycase, I made those parts, and even with a half millimeter mistake (in total), I'm still very happy with the result... I'll work the data out so I can do better next times...

After a bit of search, I should have used the manual probe to set the origin of my work...

Yesterday, I did mistake. Decide I would redo the parts tonight once back from the office, but right this time...

The side definition was already good, so I just got it done again the same way.

Then came the bottom and top sides. I changed the way to set my work origin, using the X,Y,Z manual probe as showned in previous post...

The is one small thing to consider is that part need to be large enough to define the X and Y position. One part is not enough, but two is. With a small 3m pin in the rear holes to make sure they are set the same way and that's it. Once you defined the origin of the job, you just run the first part, then swap the parts, reset the origin (unless you are fully sure of the position, and in that case you can skip this) and run the job again for the second part before delaing with the second additional face...


And yes, threads are defined as well...



And in comparison to what I've done yesterday, you can see the difference by yourself. Note for self : don't do this mistake again

My first parts with mutiple parts being done, I've started to think about the next parts of the ST-1 SP version. Considering what I have in terms of aluminium blocks, I decided to revise the uprights with aluminium 10mm thinkness in mind as it is what I have.

I know the geometry works, and in my mind, it is easy to reconfigure the parts while keeping the target to work with the same geometry setup. The master will also require revision, but that should be easy enough, at least in CAD, specially considering we do'n't need some of the nuts inside the upright, as the upright will be definitely threaded properly to fix the screws used as shaft for the wheel carriers...


But while this would be super easy to think in CAD and to 3D Print, CNC means substractive, and means working face by face, so we need to think about strategy, and strategy includes fixation of the part for each side we will work on... Uprights being symmetric, that will reduce the number of faces to think of... But we need to be able to take care of the two uprights at the same time, and therefore I designed the set of parts together.

Anyway, I love puzzles, and CNC is giving a lot of room for those...

Had a lot of thoughts last night about how to proceed for the part... I ended with the idea to create two supporting parts...
The first one will be done in order to be able to do both top and bottom faces properly


The second part is slightly different and aims to lock th epart during the definition of the external face as I need to do some holes here... The part will be taken in sandwich within a vice so it won't move while working the external face. This will also allow an easy location of the 0. At the end, there is at least one hole which won't be used in my design as I decided to take it differently (you can't use this hole to define a face as you need to drill it first with the face defined - chicken egg situation, which means approach change).


A last contouring operation will be done in order to finish the cuts of both uprights... That's for the plan...
I cut the supporting parts, and I'll start the process tomorrow for the uprights...


I'm not totally sure of my thoughts, wish me luck...

I'll probably have to redo the parts differently... As I'm almost sure my failure point is my first step, when I did the three holes...
There might be a better way : I'll probably gain by using two centering pins diameter 4 and a larger stock.. And less pocket operations and more contour to work quicker...

Lesson learned : screws are not precise enough to set a position...


I decided for another approach using centering pins.
I had some remains of a cut available. I'll use this as my support... Drilled 3 holes for setting the position, and 3 others later on for the fixation...

And fixed my stock on top of it (I prepared the stock with the required holes with the same deinition than for the support).


Then I started to cut pockets, countour and chamfer...


Then turned the part and fixed it again and applied the same operations, and included drilling and thread for the steering rods...



Next was the side operations... For this, I added centering pins holes in the first parts I did yesterday...


And started the operations...



Last I repositioned the support against the anchor, applied a contour operation for the final cut, with as smaller bit and an offset to make sure I do not make mistake...


Lessons learned :
- Work origin based on anchor is ideal
- Support should ideally never move during operations, or fixed with a proper reference point (anchor 1 or 2)
- Centering pins allow for precision (pins are diameter 4, holes with a diameter of 4.06 are perfect)