Playing around with the CNC Router

[Sgt_Mike]

several years ago I bought a cheap desktop cnc router to just play with. To see if I wanted to get into a actual full grown cnc router. I eventually stepped away from it for a bit, so it has been sitting in the corner. I repurposed the computer I had hooked up to it. enough time had passed that I actually forgotten all the tricks I learned.
The other day I dug it out and decided to play with it again.
Using a scrap bit of Mahogany, pulling a old i-7 laptop I attempted a 100mm coaster design (4mm thickness).

After the 10 + hours of carving, I applied Tung Oil and it is now drying before the next coat /sanding (need to find my 1000 grit sand paper for that) .
The engraving depth is 0.5 mm , which actually did pretty good Except for the banner within the snake above the coat of arms. Seem to wipe out the words "This we'll defend", Thinking I'll need to do this as a separate operation / cut at a lot less depth. Which is what I did with the cut out border. I did try a piece of oak I had, prior to this but was done at 60mm diameter because of the size.
As one can see the flaw in the right upper area is from a miscut years ago, hence why it's scrap.

here is the oak for comparison on the right.

again Tung oil finish, and need to finish it out even though these are not the level of precision I desire, just need to figure out How to get what I want with this logo.
I need to bother one of my neighbor to use his bandsaw to cut them out leaving me with another usable block to do a set of 2, 3, or maybe 4.

Thoughts? Wasting my time? I have / am considering using the site's logo in order to see how that cut is, not to be for sale of course just to see if it's viable.

 

[Kwarw1]

That's pretty neat. A pretty detailed design as well.

 

[Sgt_Mike]

here is a Load block I did for a buddy of mine using scrap of end grain maple and African Mahogany border for his .348 Winchester. three years or so ago

 

[Sgt_Mike]

As you can see I had some run away with the endmill, this was done several years ago. Not a great job, but he liked it as his load blocks didn't work with the .348's rim size.

 

[jmeddy]

very nice--keep at it.

 

[Sgt_Mike]

I chose the Army Seal because of it's detailing, once I figure that one out fully, other designs will be easier.
(I am secretly eyeing that nice piece of black walnut in the corner, would make excellent coasters, or ???)

 

[popper43]

Most tung oil isn't anymore. Oak will need some color for contrast.

 

[LONEHOWL]

Nice!

 

[cherokeetracker01]

I think you're doing great. Let me know when I can turn in an order for a S&W loading block.

 

[Sgt_Mike]

Let me know when I can turn in an order for a S&W loading block.

I'll have to check the server I "think" I had the files (for loading blocks) to run on it, otherwise I'll have to start from scratch again. Which will entail reloading Freecad on the laptop to get the file redone.
Just checked the server ... nope.... now digging through "pen" / thumb drives IIRC correctly that is where I had them. Funny how those thing hide when you need them LOL ....
I do need to finish the coasters first before diving off into another project. (btw the finish on the load block for my buddy was simply J-Wax, and 2000 grit sand paper).

ETA:
went back to a online CAM software reset some parameters to reduce the depth on the banner and snake to 0.08mm (approx 0.0035"). This worked to allow one to actually read the motto "this we'll defend". Which I also reduced the depth to 0.3mm (0.012") from the 0.5mm of the rest of the seal which should present more detail than it currently is displaying.
Now all that is left is to combine the two files so that it is a continuous cut on the next one. Which hopefully will be the last tweak for the DA seal coasters.

 

[Sgt_Mike]

@hunt0168 sent some extremely helpful tips via PM / conversation. While his application on it's face is different, it is exactly the same.
Regardless of if it's a router, Plasma cutter, or a laser. Codes are the same to the controller and software, with only a few differences. The best thing in his reply was use a area off of the workspace to test. Which I honestly did think of prior to him sending the advice, which I'm thankful of because had I not thought of that.. yeah his advice is a game changer. Which he covered quite a bit more, all helpful advice. Leveling the work piece, I do have the bit (fly cutter) for that.

Work time, the very first cut (60mm) when I re set everything back up took 20 hours, and as smaller area. I then increased the size to 100mm. Set the software setting to geometry so the cutter is making cuts closer to each other. This setting alone cut the time in half. Engraving a graphic is the most time consuming. Straight milling a pocket is fast as well as the border cut out. Depth and number of passes each step also plays in here which is why a mill or cut out is faster, as they can be more aggressive to a large degree. Wood species also plays a large role in the speeds and feeds setting.

Below is the test of Just the banner above the coat of arms focusing on motto's clarity. (looks better in person)

Most tung oil isn't anymore.

Very true, and hasn't been for years. However it can be readily obtained. Several vendors do offer it, just usually will not find at a "Box" store.
For this project I'm using the "fake" Tung Oil, which has lacquers in it to fill the pores, and build faster. As it's not a vintage stock or a butcher block or item that needs "food Safe" is a issue. But something to set a coffee cup or adult beverage on. But is a true and valid point that popper pointed out.


Actually just looked at the date of the photo of the load block yeah Oct of 2023. yep been a minute or two.
Now the only hold up is getting the neighbor to use his bandsaw. Kinda wish I had not sold off the one I had. But for piddly stuff like this a simple cheap desktop band saw will work.