Vise Clamps

I got sick using kludgey clamping jobs to hold the 2" vise to my CNC's table. I came up with a clamp concept a while ago, but I never got around to making a set until a few days ago when I found the right sized stock in my material pile. I was too lazy to find the drawings I had made of the clamps so I went by memory on the shape and I made up the dimensions as I went. I also decided to play around with running my spindle at 20,000 RPM. Both the parts and my test cuts turned out great. I was able to cut the parts at more than 5 times my usual material removal rate!

 I used 4 blocks to hold my vise down. This vise is one of my favorite finds. It has incredible specs for parallelism because every face is precision ground, and it practically cost nothing. The only downside is it's a pain to clamp parts with the screw.

The clamps are made from .5" square stock aluminum. They are 0.01" shorter than the surface of the vise they clamp onto. This ensures they actually clamp down. I bolted down the vise in less than 30 seconds with these new clamps. Another added benefit of these is if I decided to add a second vise they won't create a large gap between the additional vise. GENIUS!

Guitar Bridge

I finished the bridge on the guitar! I actually started it last summer when I made the string adjusters and half of one of the parts that makes up the base. I made most of the base at school but still had to complete the half finished part. It took me less than an hour to pop it out (including writing the code which is done by hand rather than with a CAM program). 

I also have a new phone so the camera is less blurry (mostly because it doesn't lag while taking pictures).

I also finished up some more of the head last week.

 I had reverse-engineered some tuning knobs into my CAD from a drawing that I had found online. When I went to one of the guitar stores I found the EXACT same ones I had found online. I had to buy them once I realized that. It saved me a ton of time when designing the head.

The head turned out pretty nice. It still needs the string alignment posts.  I have the material for those turned down to the right diameter, but I still have to cut them to length. Ill finish those when I get bored milling and want to switch to running the lathe.

 I also got a new set of calipers. They're a bit bigger than my old 6" set. You can really only make parts as accurately as you can measure them, so I figured it would be good to get a HUGE (40") set of calipers to make those giant parts to within 0.001 inches. It looks like my neck is about 0.001-0.002" over 19". I'd say that's pretty good considering I had no way to check the dimensions of my part as I was machining it.

The guitar is slowly coming along. If I finish the main piece for the body I'll basically have it in a playable state. I hope the resonance of the aluminum gives it a unique sound, but doesn't make it sound awful. I do have some plans to add damping material into the neck if the resonance makes it sound strange.

Guitar Neck

The last few days of school were hectic. I managed to secure the time I needed in the shop and pumped out the aluminum part of the neck. I also was able to pack all the junk in my dorm room back into my car. The poor thing was probably past its maximum cargo capacity especially with all the material I accumulated over the semester.

Profile machining the neck took alot less time that I had thought it would. I didn't want to switch the CNC to 3-axis mode, so I did everything by manually adjusting the Z axis. It was a little slower than running full in CNC, but it kept me from scrapping the part with a stupid code error. I think there were 8 or 9 passes per side. It was machined with a 3/8" ball end mill. It has a really cool machined texture. Its much better than a perfectly smooth curve.

I realized my camera was at home, so I used my wonderful cell phone camera. I'll work on increasing the picture quality in the future.

I don't think I need to polish the neck either. The machine left a nearly perfect finish on all of the parts. The dimensions were all within 0.001". I love it when a part comes out perfect. I still need to break all the sharp edges or I'll lose a finger when I slide my hand across the fret board.

Guitar Fret Board

I've started to move into guitar production. With school ending soon, by opportunity to use a large CNC is also ending soon. I figured I'd do the pieces which were the most difficult to machine first so I might have a hope at finishing the leftover parts during the summer.

Using 2 vises is GENIUS! They made the setup much faster than if I had bolted the part to the table. I left them on the machine (usually there is only 1 per machine in the school shop). I'm pretty sure others will appreciate not having to unbolt the vise anytime they want to make a part larger than 8" wide.

 I missed a bit of the surface while facing the top. It really didn't matter because it would be almost completely machined away while cutting the frets. The fret marker screws were cut perfectly so they would be flush once the frets were machined into the board.

The pattern from the tool path looks really cool, so I've decided not to polish the fret board. It isn't really visible in the picture, but all of the frets were rounded with a corner rounding endmill.

I hadn't machined any stainless in a while, so I forgot how painful it is to machine compared to the usual aluminum. The machine really wanted flood coolant, but I didn't have that option since the machine wasn't fully enclosed. Next time I'll make sure I use a full machining center when I go to make a big stainless steel part like this. I was also too lazy to do any bit changes so all of the frets with a 1/4" carbide end mill. It just slowed down the process to the limit of my patience.

Also I've just about had it with my cell phones camera... the pictures it takes look like crap. I swear they get worse every day. I'll probably go back to using a real camera instead.

Rocket Nosecone

One of my school projects required a "biconic" nosecone. This type of nosecone has lower drag than a normal round one once it breaks the sound barrier (at least this is what we were attempting to verify). Biconic nosecones are basically described by their name. They look like 2 cones sandwiched together into one shape. We were not able to buy one for the size of rocket we were building, so the obvious answer was to make it!

We found some 2.25" diameter polycarbonate stock in one of the material bins at school. We decided that it would work fine and look pretty cool on the rocket. The challenge with the nosecone was that it needed to have a thin wall throughout its entire length. I decided it was best to machine the inside first and cut the outer profile last. This was the only way I could see how to grab nosecone in the three jaw lathe chuck. I got to use my new boring bar for a legitimate project! Sadly the boring bar really wasn't meant to cut materials while hanging out 5". The boring bar is less than 1/2" in cross section, so it was sticking out more than ten times its diameter. That violates every rule of thumb for cantilevered tools that I can think of. Generally you don't want a part sticking out more than three times its diameter and a tool more than 5 times it diameter. Sometimes you just have to suck it up and use what tools are available, so I used the boring bar anyways.

It made the most horrible chatter I have ever heard on a lathe. Both the polycarbonate and the boring bar were resonating. I tried numerous speeds, feeds, and depths of cuts but it was hopeless.

It didn't look as bad as it sounded, so I machined the other side.

 The normal lathe bit worked great on the outside. It was nearly silent and left an almost perfect finish. It was about as perfect as you can get in polycarbonate without polishing.

The nose cone turned out pretty decent. Hopefully the actual project turns out well... my grade depends on it.

Light Saber FINISHED

AWWWWW YEEEEAAAAHHHH!!!!!

I actually finished a project in a somewhat reasonable time frame (factoring in that I had class and plenty of homework to keep me busy).

So here's my secret "power source" for the light saber -- A Maglite!
It has an LED instead of the usual junky light bulb. The reflector in it also happens to be the perfect shape to illuminate the blade nearly uniformly. This idea was GENIUS!

Another GENIUS idea was the use of a custom machined collet to hold the blade in place. It makes the blade easy to replace and holds it in like... a real collet.

 I used a slitter saw to cut the slots in the collet. I was amazed at how nicely the saw cut the slots. I will definitely be using the slitter saw in the future.

As you can tell the main body was bored pretty deep. Every surface of the 1.9" diameter 8" long body was machined. Inside and out! I used a boring bar with an immense reach - over 4" considering the smallest diameter it could cut was 0.5625".

 The light saber looks pretty good in the dark. I might replace the flashlight with a custom made lighting system later on so I can get a different color. For now the white looks fine and makes it that much more unique.

These are all of the parts used in the light saber. The screws are used to bolt the two ends onto the main body. The flashlight is held in place by the plastic ring shown next to the collet. It is turned on by the pointy looking acrylic piece in the back to the left. The blade got a rounded end cap to prevent injury during duels. (This light saber cut the blade off of one of the cheap "official" ones from the toy store)

I ditched adding the gears around the hilt. It wasn't worth lifting the 8" rotary table from the floor onto the mill =D

As you can see the light saber was put to good use battling the snow.

This project doesn't really have any pros or cons. It looks cool and that's about it. Until I make a second one I can't test it out in battle, so for now its mostly an art piece I guess.

Light Saber - New Project

I have to stop coming up with projects...
Anyways. This one is more of a machining exercise than a design project. I wanted to test some new tooling and machining techniques on the CNC lathe at school. This is the first real project I'll have tackled on a CNC lathe before, so this should be a great adventure.

The idea for the light saber is that it has to feel as "real" as possible. (Yes I know real and light saber contradict each other, but I wanted to make something Obi-Wan might pickup by accident.

I tried to keep the center of gravity on the hilt. That way it might behave as if the blade were made of light. Since I didn't even attempt to invent something that actually performs like a light saber I figured polycarbonate tubing would be adequate for the blade. This way I can actually hit things and the blade probably won't shatter. I threw in some gears at the top because I thought it looked cool and I have some leftover stock from machining a few parts for someone. The "power source" will remain a secret until I verify it works.