Working on the skateboard parts again, and decided to switch up the toolpaths a bit to get a better surface finish.

The primary issue I was dealing with yesterday was tool vibrations (see the previous post), which left small marks all over the part. The cause of this consisted of two factors that played nicely together. 

The first was the tool stick out; due to the height of the piece, I had to have the ball endmill stick out over an inch from the edge of the collet; this makes the endmill not as stable, and change in axis (x&y) could cause the tool to deflect (jumping side to side). 

The second is how much material I was cutting with the ball endmill; I had the part roughed out with a 1/2" square endmill and ten thou (0.01") stepdowns leaving eight thou on all sides to be removed at the final finishing passes; because of the amount of material that needed removing coupled with the long stick out caused a lot of vibrating and small marks on the part. 

I decided to come in first with a 1/4" ball to clean up the steps from the 1/2" endmill and leave two thou (0.002") to clean up with the smaller ball cutter. For the tool stick out @tuesdayandthursday suggested I try a tapered ball endmill; this would give it much more rigidity when reaching down the tall walls on the sides of the part. Thankfully I found a ball endmill roughly the same size as the one I was using previously (so I could make a fair comparison) and tried it out. I got a significantly better finish, and I didn't hear any tool vibrations throughout the whole operation. 

The only thing I am not super pleased with is where the tool changed directions on the machine, and the endmill dwelt for a fraction of a second, just enough to leave a slight mark. I haven't looked into it too much, but I'm pretty sure there is a feature to allow the tool to glide around corners instead of doing a hard turn. I tried playing around with the tolerance and smoothing tolerance settings in the passes tab but couldn't see any significant changes (used 0.00021" tolerance for both).

I am working on a set of skateboard parts today on the Haas VF2.

One of the difficulties I ran into pretty quick on the first part was how long I had to stick out a couple of the endmills I'm using. There is a large bump/cup shape on the top of the part that has a very organic body to it, which requires a slow spiral toolpath with a ball endmill to ensure it all flowed nicely together. Because of this, I had to use a smaller endmill then I usually would to get into all the crevices and would have to have it stick out over an inch to get all the shallow features. Unfortunately, this meant the tool would vibrate while cutting the aluminum and left some weird surface finishes. Thankfully these parts will be tumbled afterward, and that will remove all the marks left by the vibrations but isn't my best work, and I may switch the toolpath up for a morphed spiral to see if I can get a better finish. 

There are also two slots at the bottom of the part I needed to mill out on the part which I tried to do on the first operation with a 1/8" endmill and 1.25" tool stick out, but the vibrations were so bad it left a horrible finish. 

Since this is a skateboard part, the tolerance doesn't need to be super high, and the looks matter more than accuracy. It still is an exciting challenge to machine out all the small features and getting good finishes in a relatively short period. There are a few small pockets that require a 0.04" endmill to clean up, which requires quite a bit of the machining time. 

This first part will consist of three operations, first and second will get the majority complete on the 3-axis mill, then it will be finished up on the 4th-axis to get a couple of small features that I'm not able to reach on the previous setups. 

Designed the new tool setup and breakdown workstation today! I'm super excited to start using this and getting everything organized neatly, which will make finding tools much easier!

We've got over a hundred slots for tool holders to sit on the top allowing all the machines to be completely broken down and all the tools put away at any given time. In the past, we would have issues of not enough places to put all the holders and would have to leave the VF2 with the unused.

It's going to sit on three rolling toolboxes with a big butcher block to use as the tabletop. Underneath the tools I left big open areas for tooldrawers to sit which will hold all the drill bits and reamers. Then on either end, there will be the tool-holder holders to take apart and set up the endmills for the machines. In the past, they would be set up on the mills themselves, which is handy for quick changes but doesn't make sense to go back and forth through the shop to pick up endmills and drill bits. 

After the design was all finished I took advantage of the drawing section of Fusion360 and drew up some quick plans for the workstation, then printed it out and my boss sent it off to the shop next door to get it built. 

No contract work today, so I got to spend the whole day cleaning the shop from top to bottom!

Still working the design for the re-organization of the shop tool holder station and setup/breakdown area. Also, talking with my boss a bit about possibly taking on more small-time production work for the shop and hiring on a new guy. He went over some of the areas he's faced in the past and doesn't especially like production work due to how hard you have to push to get enough work to pay for everything. It's a big game, with big wins and significant losses if contracts don't come through like expected. One of the ways to shield yourself from this is to diversify into different industries/companies instead of going with one major contract from a specific business, where if they fall through, you're up a creek. 

The shop isn't set up for any kind of production work as-is and would require some changes to the way we do things now to get to that level. My boss is specifically thinking of small-time production, with 20-100 parts maximum per run, not trying to compete with China or shops set up for thousands/millions in production. 

What Does a High-Level Machinist Look Like? 

Lately, I've been asking myself a lot of questions on what I want to be doing long term, what brings me joy and passion in my work, and what are the steps I need to take to be a high performer in that field?

I've really enjoyed Brendan Buchard's book High-Performance Habits, where he outlines what the top performers look like and how to get to that level. One of the things he talks about is finding your PFI or preferred field of interest, and I've been struggling to see what that is for me. 

The stumbling block I keep encountering is that I'm getting caught up in; if I make this decision now, I can't change it later down the line, and I'll be "stuck" in whatever avenue I chose to pursue. I'm not thinking big picture, thinking what interests me now and what I can do right now, not looking for the super long term but the 3-5 years from now and that journey. I enjoy machining and have an excellent job prototyping and learning one on one with a high-level machinist. I'm not sure if this is "my thing" or not, and I'm scared to get in too deep and feel like I've wasted my time (which I know I won't). 

I decided to make a decision and find out a bit more about the industry and what top performers look like in it, or more accurately, what does it take to become one of the best in the field and what steps did those people take? 

Through some research on google, I found an excellent article on what machinist material looks like by Leading Edge Industrial. They outlined the major five areas that all good machinist has in common. Those are Precision - 1) Detail-oriented, drive for perfection, and quality. 2) Analytical, collecting information quickly, and making decisions. 3) Creative Problem Solving, thinking outside the box, able to understand new and unique ways to solve problems. 4) Patience, making mistakes but not getting caught up in the minutia of the problem, but taking it in stride. 5) Pride, to be proud of one's work and the job completed, having satisfaction in the craft, and enjoying the process.  

Today was probably the most nervous I've ever been to complete the final operation on the parabolic mirror part.

There are three holes on this piece, one meets down to another side pocket that I milled out on the 4th axis, and the other two break through the bottom of the triangular piece; they are all over five inches long. The sketchy part about this was how long each of the drills had to stick out to remove all the material. One of the drill bits was only gripping about a quarter of an inch in the collet and would ring when I put it in the VF2. 

Since each of the tools was so long, I took the advice of my boss and put together some shorter drills to remove about half of the material, allowing the more extended drills not to work as hard. Before coming in with the longer tools, I used a center drill and set the path to prevent any deflection from the first peck.

Thankfully everything went smoothly, and I slowed everything down quite a bit to let everything take its time. This was the only part I had, and I didn't have enough time to make another one if this failed, so everything was slow and steady. After the drilling was finished, I used a tapered threadmill and hand tapped the holes that needed it, then deburred everything and packaged it all up. Definitely a unique part and had its challenges, but I'm delighted with the outcome. 

Working on the soft jaws for the parabolic mirror part today turned out to be much more complicated than I initially thought it would be.

Because of the triangular shape, I wasn't able to machine the soft jaws with the part centered in them but had to use the flat of one angle to meet up with the back flat of the other jaw. This would allow one side to brace it up, while the other would have full clamping pressure against it. 

I also had to hold the part very deep in the jaws to ensure it was stable enough to drill through the rod from one end, due to the cavity in the top of the piece. Because of this, I had to use very long tooling to get down into the 2" soft jaws; my boss instructed me to have three setups of the same tool, each at a different length to get the finish as clean as possible. Then at the very least, use the longest tool to take very small and slow stepdowns along the face of the wall to give it a consistent and clean finish. 

Really sketchy part to make and came close to a machine crash a few times, and the final operation I'll be doing tomorrow will be with a six-inch drill and taking everything real slow. 

Very excited to get back to work after the long labor day weekend. 

Today I was working on a part for a parabolic mirror, which will be one small piece apart of a large, very powerful flashlight/laser. The issue I had last time with this piece is a small inner groove where the 1/16" endmill would leave a mark where it retracted out of the part. What would happen is the tool would dwell for a split second, then retract straight up; this was just long enough for the endmill to leave a circular mark on the surface finish (it was only visible, and when you run your finger across it, you can't feel any difference).

I was able to fix the surface finish issue by going into the linking tab in fusion360, where you set the lead in's and out's and programmed it to do a slow arc at a 15-degree angle upward as it fed out. I was able to try it out and got some pretty decent results; I am still able to see where the tool exited, but it's nothing I can't clean up with a little scotch bright. 

The roughing on this part did take longer than I would have liked (at about 55 minutes with a 1/4" tool), but even that made the machine sound like it was pushing pretty hard, even though I've pushed this particular endmill through much more and had excellent results. My guess is that since I am using the 4th axis, the stability isn't as great as the vice, and so vibrations play a much more significant part.

Fixed the program this morning and got the Haas VF2 up and running again on these vent covers!

I tried something different this time around; when removing the material from the center pocket above the vent grooves, I decided to use the slot clearing method with the 2D pocket toolpath. I haven't used this specific programming method very much in Fusion because of the stress it could cause on the stock and or tool. Slot clearing puts your endmill at 100% tool engagement, which could cause chip clearing issues or too much strain on the material, causing it to vibrate or come out of the vice. To my surprise, it worked out exceptionally well and had the settings just right where I got little vibrations and maximum material removal. 

Learned a tip from my boss for when bolting anything on an already finished surface, you can use soft metal washers (such as copper) to place under the steel screw. It allows you to put quite a bit of pressure on the bolt without worrying about marks on your part.

I also got to use the manual programming section in Fusion360 CAM, where you can add special code to your program. I didn't get too deep into it but used a basic machine stop for when I needed to add the bolts to the part. The downside to the programmed stop is that unless you have it positioned in between a tool change the spindle doesn't turn back on after starting the machine up again. I haven't looked into it further and may be a simple explanation for this but I thought it was interesting. 

The final deburring and clean up I was able to do with an India stone which works really well with small burrs and perfect for flattening surfaces. 

Finished up the first of the Range Rover vent covers I've been working on today. 

This piece was a two-side operation, the first consisting of machining the front vent slots, rounded edges, and drilling location holes to locate the part when flipped over. To find the position in the machine, I had to make a fixture plate that would allow me to use pins and bolts to hold the part on the bed securely. Since the piece was quite large, I used the same size stock when making the part of building the fixture plate. The programming for it only took a few minutes and consisted of facing it to ensure the face was perfectly flat, then drilling holes for threading and location pins. 

Initially, I used a 2D adaptive clearing method to machine out the pockets in part on the second op, but the machine time was over twenty minutes to do it all. After discussing it with my boss, I came up with a new strategy to remove all the material in just a few minutes; the 2D pocket clearing allowed me to ramp down to the bottom of the cavity, then slot out the aluminum. I'm always a little nervous about using slotting techniques to remove the material as I've had bad experiences with it in the past on hobby machines. 

I did notice that I made a few mistakes when tracing the part and forgot to account for an edge that went out farther than my selection, I was able to fix this by manually drawing in the geometry to go farther than it had before. I also forgot to add another contour toolpath to finish off part of the rounded part in the front of the peice. 

Overall I'm very pleased with how it all turned out and am super happy to be able to show what I'm working on without having to conceal certain aspects of it!