Posts for Tag: Oneshop

Oneshop Redding Cutting Aluminum (part two)

Over the past few days, since I did the first aluminum cut, I've been researching the most efficient ways to cut aluminum with a clean finish.

I found that the vertical cutting height should be much higher than my previous 0.2mm. This time I set it at 6mm cut depth and place it at 0.1mm optimal load; the sound wasn't quite like I would have liked, so I tweaked it a bit and got to sound a bit better.

I also found that using compressed air helps with chip removal; I already knew this, but I found with a combo of compressed air, and the silicone gets a clean-cut, and you can see what's going on.

I was able to cut down the stock to about 5mm and then start cutting out the logo design that I modeled a few weeks back. It all went very smoothly without any hitch, though I did have to be there as I didn't trust it on its own.

I started with a 1/4" 4 flute carbide bit to mill out the smaller stock, then switched over to a 1/8" 4 flute carbide bit to clear out the shallower areas and to do the final touches.

The significant difference between this cut and the previous cut operations I did the other day of the same model as I didn't understand how to set the Rest Machining option; this means the rest of the stock to cut from the previous operations.

I tried something new here as well, which was taping the underside of the stock and the board and glued the two sides together for a more secure fit. I did this primarily because I knew I wanted to cut the part out of stock, and I didn't want it loose.
I noticed that toward the end, one side of the stock was higher than the other and so I started cutting into the tape before its final pass, which was not ideal.

Since I had to be there watching and blasting it with air, it was not ideal. I've got an idea to add a few nozzles which I can attach to the air compressor so I can let it run on its own.

So the bits I got from my brother (see earlier post) were for cutting steel and titanium, which, as it happens, is not ideal for cutting aluminum. I thought it would be just using a harder bit than necessary but would work just as well, but not.


Oneshop Redding Cutting Aluminum

After acquiring the aluminum stock and endmills to cut it, I need to figure out what feeds and speeds to start cutting the material to achieve a decent outcome.

I started with a flat plain cut to remove some of the access material and give it a smooth surface to begin my next operation. I didn't realize till I started cutting that the aluminum stock is not perfect perfectly flat on top, I added an extra 0.5mm to the top of the stock to clear it off in case it was imperfect, which worked out well.

I set it at 203mm/min (8in) and 0.5mm stepdown with a 1/4" 4 flute endmill. I can probably have more of a stepdown and even increase the speed, but I'm playing it safe for now. These bits are seriously expensive, and I don't want to ruin anything in my first go.

The outcome was not a huge success; the tool edges were a bit worn just slightly enough that it left some stock when it should have cut. The chip evacuation wasn't the greatest either, so I'm going to try using compressed air and silicone wd-40 lube to give it more of a chance. Overall though the places it did cut have a very nice finish to it, something about CNC cut aluminum feels so good, such a perfectly smooth top.

The sound of the machine didn't sound like I was hoping. So for the next cut, I'm going to lower the optimal load on the bit, which should decrease the size of the chips and have a smoother finish. While cutting the aluminum heated up quite a bit and got to the point where it was too hot to touch, I think the reason why it was heating up so much is because of chip evacuation; the chips couldn't get out fast enough and so were recut and started welding with the tool. The outcome was a very rough finish and a definite color change along with it being much sharper of a surface finish.

Attempt number two, it was more successful than yesterday, I bought a can of wd-40 silicone lubricant and sprayed it periodically while it was cutting, and that did the trick, I sped it up quite a bit faster than before, and it kept up. This time the aluminum only got a little warm and all the chips consistent and small. It sounded much much better than before and had a cleaner finish. 
I tried running a few cleanup passes but didn't quite get them down right, so I ended up cutting places where I shouldn't. Very pleased with the outcome, even though it didn't look as clean as I would have liked. One thing I keep forgetting to try is compressed air that would remove the chips from getting recut, and I feel it would keep the material from overheating.

Oneshop Redding CNC Aluminum & Bits

I finally got down to it and ordered a couple of aluminum cutting bits for the Shapeoko CNC router. I bought them off of the site Bits and Bits which has a wide selection of them to choose from. I ordered a 1/8" 3 flute end mill bullnose and the same of 1/16" for smaller details. They were both about $22 each and adding shipping that bumped it up to $54.00 which is quite a lot for just two bits.

Shortly after they came in my brother gave me 14 used endmills from his shop down in Nevado CA as a late birthday gift. This was great as they were easily $20-35 a piece which I could never afford on my own. They were a bit worn from cutting titanium but a few of them where in decent shape. They ranged from a 1/2" thick to 1/16" which is going to really give me a wide range to practice with. Unfortunately, the Shapekoko can only hold up to 1/4" bits so I won't be able to use the 1/2" unless I get a new holder for it.

As for cutting material I looked a bit around online for different grades what's recommended for first cuts and found some inexpensive 6061 aluminum for $17.00 for a block 11.5"x 2.5"x 1/2".


CNC Machining Oneshop Redding error33

Alright, back at it again. So after running through a simple path to see if it would stop before completion I found that it still does, what would happen is it would go through about 40% of its path, then give the carbide an error code (error33) and stop the toolpath, I've gone through a bunch of different cuts, sometimes trying them several times and nothing worked. I've tried different outlets, different power banks entirely for the router but always had the same result. I asked my brother as he mentioned having some similar issues and tried his solutions but didn't work. What he had done was to lower the fine tolerance of the passes to have a rougher cut out, then come by later with another tool to clean it up.

After looking a bit online forums I found a few possible solutions. 

Carbide 3D's Shapeoko cnc machine was originally designed in metric VS imperial. It supports imperial, however it wasn't designed specifically for this and so has to do calculations to convert it to that and so has a lot more of a load than if you where working with metric. If this is the issue then simply designing everything in imperial then just switch the units it measures to metric when setting the tool paths.

This would also explain why not so many people are having this issue as most people use metric for designing and creating toolpath's. Which I primarily use as well but didn't have any metric measuring tapes when setting the stock and so set the unit of measurement to imperial.
Another possible reason for the issue is the sheer amount of digits it has to calculate and one guy said he solved the issue by rounding everything to only have at most 3 decimal spots. For instance, if the side load cutting rate is at 0.04195 you would simply round that to 0.042 and etc with all the settings. Apparently this reduces the overall load the machine has to take.

Here is a link to the forum that I got this information on: https://forum.shapeoko.com/viewtopic.php?t=8237

So after making a few modifications to the tool path settings, I set it running again and await the results.


Lazer Engraving Oneshop Redding

Oneshop has a laser engraver, the Voccell DLS can cut through and engrave quite a few materials and I was very excited to try it out. So I asked Tyler for a quick rundown on the machine and I was off. It's extremely simple to run and there is a list of materials and what outputs for each one to achieve certain things like cutting vs engraving. I did a few test runs with wood using my logo from my small side business and the speed and ease of use are insane! 

I tried it on a piece of metal with not nearly as good of an outcome but still showed up. I tried it with a painted one and anodized but pretty much the same outcome on both where it would only really show at an angle. 

After doing a couple of different test runs of a straight logo and things of that nature, I was curious on what would happen if I tried using an image and converting it to a point where it would show up on wood and still be recognizable. I found an image I liked and tried imputing it directly into the software that creates the g-code for the laser engraver, but it came up very dark and filled the entire area with a straight color which was not what I wanted as you couldn't make out anything in it. Then I remembered my father getting an app that would convert an image to have a sketchy look to it, like a hand drawing. I decided to download the app and convert the image through there, then plug it into the machine and see what would come out. This too didn't have the desired outcome, it would only show the more defined lines which didn't show very much only the bare outlines. I then took the image into photoshop and played around with the contrast, exposure and brightness to a point where I got the sketched lines to be a straight color instead of grayscale. I plugged it into the machine for an example and it looked much more promising. However, the image was of two people (my sister and her boyfriend) and his eyes came up as a straight black blob where you couldn't make out anything. I decided to clean that up manually which only took a couple of minutes and helped a lot with recognizing the people in the photo. 

Here is a photo of the final outcome and before image: