Machinist Apprentice | Finishing & Sandblasting | Day 86

Finished up all the skateboard parts today and got to try out sandblasting for the first time!

These axle truck parts required quite a bit of cleanup to get them ready for shipping, mostly due to how I went about machining them and got impatient with the machine's speed. Taking them right off the machine, I had to deburr the edges quickly, then lap the axle with the truck using a grit compound to ensure they fit together perfectly. The downside to lapping the two parts together is that now they are made for one another and won't have that same fit on the other parts. One way of removing this issue is to randomly mix and match the parts and lap them on one another, thus creating a "general fit" that matches each other. 

I also made a mistake when drilling these parts, and that was I should have added an extra toolpath to add a radius to the corners, which would have saved me a ton of time later as I had to do that part by hand. 

Once all the parts fitted nicely together and cleaned them all up with light sandpaper and some scotch bright, I then moved over to sandblasting them. It wasn't necessary at all, but we had a machine in the shop, and I wanted to learn how to use it and see the outcome of doing so. Sandblasting basically blows very light sand using compressed air and gives your material finish a satin look to it.

I'm actually quite pleased with the results, and I wasn't quite expecting it to reveal as much as it did; you can pretty clearly see some of my mistakes in the project in some areas, and others it conceals bits. Overall though, it was super easy to finish off all the parts and get them looking real nice! 

It's been a long, drawn-out project lasting two and a half weeks, but I've learned so much at this time. I'm thrilled for the experience, and it's helped me overcome quite a few misconceptions I had about 5-axis programming and setup. 


Machinist Apprentice | Skateboard Hanger/Axle pt3 | Day 85

Working on the skateboard axle/hanger pieces once again today and had quite a few small setbacks that really made things frustrating. 

Over the night, I realized that I had the stock positioned incorrectly in the soft jaws and was actually cutting the part too high. Thankfully it was an easy fix, and I could use the same piece by cutting the whole face down a bit to its final height. I also had some vibrations while roughing the part out with the 1/8" ball endmill. My feedrate is quite high for how much material I am removing and had to slow it down in the corners to prevent the tool from breaking. I also had some issues with the corners being too tight to fit with the trucks I made a couple of days ago. What would happen is I make a change to the physical model and then re-generate the toolpath; however it wouldn't update the new geometry, you have to manually go in the setup file, delete the model reference and reselect it. 

I'm a bit frustrated with how long this part is taking, and each time I run into an issue, I have to go back to the beginning and start over again. I thought the run time on this part would be about 15-20 minutes, but since I keep making changes or manually slowing things down, its well above that. 

The main issue I am running into is one of myself than the machine itself. I get an idea of how fast I think it should go, then try and push it to go that fast whether the machine can go that speed or not. This causes me to manually slow down the feedrate and other settings to compensate for what I programmed, or I mess up the part itself, causing me to start with a new piece. 

Thankfully my boss had some grit paste that he could use to shape the two parts together, creating a clean fit. And yes, I still need to clean the face of the part still.

Public Speaking | Toastmasters | Week 3

Thursday evening Toastmasters!

Unfortunately, I couldn't get my screen recording system working, so I had to film myself via my phone, which doesn't allow audio recording from other devices. Today's table topic was slightly different than before, where there were groups of three people giving a story style speech, building on the previous story told. I got to start and was given the context of "you find your aunt dead in a chair, and you're not sure why" the theme was picked due to Halloween coming up. It was definitely a challenge to come up with a quick beginning of a story on your feet, but I really enjoyed the speech I gave. Unfortunately, I couldn't record the rest of the story performed by other group members, so that you will be left at a bit of a cliff hanger.

I really struggled with putting the story together in a structured way and found myself stuttering while trying to come up with what I was going to say next. I also repeated details several times and wasn't as clear with some of the characters and their roles, or the major position of each person. I think I did pretty decent on emotion, though I could have gone into more backstory. It's a bit slow at first, but I feel intrigue starts building toward the end with the cliff hanger. 

Any advice would be greatly appreciated for how I could do better and structure my story better!

Machinist Apprentice | Skateboard Hanger/Axle pt2 | Day 84

Working on the Axle/hanger part again today and worked through the drilling and finishing of the sliding features on it!

Drilling the through-holes was a bit sketchy, and had to take things really slow to ensure I didn't break any drill bits. I had to do it in two stages, first drill one underside hole half-way through the stock, then flip it over and do the same, and finally come in with the final diameter hole size and take one single pass all the way down to the bottom. It worked out quite well, and I had all the parts finished in no time. Unfortunately, the inside bore almost looked like it had a circular interpolation and looked like the tool wobbled as it went down. Testing it with pin gauges confirmed my suspicion, and it wouldn't slide all the way through. My boss was able to fix this problem by turning the spindle on 500 rpm and feed the part by hand to clean up the side walls.  

My boss then took the parts over to the manual lathe and showed me the basics of how it works and turned down the outside face to its final diameter. From there, I was able to program up the final operation, which consisted of some grooves that would fit the skateboard truck pieces I made earlier this week. It has very basic features and just required some parallel toolpaths with a few holes drilled. I held the part in soft jaws by cutting a square groove down to grip the sides of the cylinder, and the bottom of the slot allowed me to set the height.

Because the part is cylindrical, I had to get creative with my work probe and do several cycles to get all the axis dialed. 

Unfortunately, I couldn't get all the parts finished up today due to limited time, but I've got the program proofed out and can load parts in and hit the start button. 

Product Development & Launching | Design & Prototyping | Pocket NC Workholding | Phase 1 pt3

Continuing where I left off yesterday with the design aspect of the new workholding system for the Pocket NC. 

After quite a bit of thought and researching online, I found quite a few flaws with my original design. 

One major one was the price of dovetail cutters already on the market; unfortunately, I underestimated the cost for small 1/8-1/4" endmills and found them going upwards of $100 per. My two main goals with this product are efficiency and low cost, and if the cutters alone cost $100+, that really limits my market. I decided to do some looking around and tailor the cheapest cutter I could find to my design. As it happens, there was a 1/8" dovetail endmill from Harveytool (#995208) for only $66.80, which isn't all that bad. 

Another key thing I didn't really take into account was the size of the clamp itself. Since I 3D modeled it, it was hard to get a good idea on the actual scale in proportion to the machine, so I decided to 3D print a quick prototype, and just as I feared, it was quite large. I decided to scrap my original design and start from scratch. I researched online and found some of the more common designs for dovetail workholding and took inspiration for the new one. I also wanted to focus on making this part easy to manufacture with a simple and elegant design.

Here is the Duif Workholding v2.0 with an external clamp vs. the single-piece design of the v1.

I also commissioned a new logo for my small business project on Fiverr for $10 to make my product look more legit. I should get the first concept design in the next few days!

Spent 2:23:00 today on the project, bringing my total time up to 6:40:00 out of 20:00:00.

____

Public Update Post - Instagram @duifworkholding

Working through the design a bit more for the Duif workholding and found a few flaws in my previous design. I 3D printed my initial clamp system to see how it would sit on the Pocket NC, and I didn't really like how large it was. I ended up completely overhauling my original design for the V0.2 you see above. With this new clamp system, I changed how you grip the material with an external clamp piece and dual screws to spread the stock's gripping force. I also modified the dovetail angle to match with a cheaper cutter sold by Harvey tool. 

I will be setting up an email newsletter very soon with design updates and features I will be adding to this product and get a timeline for product release!