I have tried a few methods to open angle past 90 degrees. The 4lb hammer method was very tedious for some of the longer pieces so I used the bench vise and WD-40 to squeeze the angle open. This would have worked much better with a chunk of steel or something to squeeze against, but I could have wasted a bunch of time finding a suitable chunk. Instead I stacked a bunch of pieces of scrap aluminum together–this was a pain, but now I’m done :-) On the plus side, it was very easy to control the angle of the squeeze over the entire length of angle.
Tag Archives: angle
Aluminum Angle Bundle 13
Didn’t spend much time actually constructing anything on the airplane this week. The last part I was working on is the flap detent angle. This has notches where the flap handle rests at 0, 10, and 30 degrees. Other people have added a detent for 20 degrees so I decided to give it a try. I spent far too much time researching other peoples’ designs and noticed some people added nibs to more than just the 30 degree detent as shown in the plans. Then I noticed a couple people mentioning the flap handle getting stuck in flight and it seemed to be due to the flap lever bending within the detent and getting jammed in–easily solved by modifying the geometry of the detent. Needless to say I fantastically over-thought the part and decided to go even more extreme and draw it in CAD.
I found SolveSpace, a simple parametric CAD program that is very intuitive, and drew my own version of the flap detent angle. Then I decided to cut it into aluminum on my wood-cutting CNC machine. I was trying 25ipm with .03″ passes and it was estimated to take about 20 minutes to cut. It was obvious I was cutting too fast–the tool was chattering like crazy so I quit and will cut it with the band saw.
I’m not counting all the time I spent messing around this week to my build time :-)
Here’s a video of me creating the part in SolveSpace:
Aluminum Angle Kit 9
Snowmageddon 2011 hit and I was unable to buy a replacement blade for my band saw until today. I bought the same metal cutting blade as before, but not without scouring the internet and a local machine shop. I was really tempted to get something really nice like a bimetal or carbide blade (these seem to be around $30 online). The local machine shop offered to weld a bimetal one for me for about $80–they aren’t really set up to do this for customers. I was too impatient to wait for an online order, so I settled with the Lowes one again.
The new blade cuts just as good as before, but made an annoying clunking sound once per revolution. I traced this down to a piece of dull metal sticking out in front of the teeth at the weld–this was smashing into my aluminum once per revolution. I ground this off with my dremel tool and it was working great.
I started going back to parts I cut to size a week or so ago and finishing the more complicated cuts.
The curves were supposed to have a 1″ radius. I found a conveniently sized container with the same dimension and traced that. I need to figure out what everyone else uses for these types of cuts. I did consider cutting out a bunch of circles on my CNC machine.
Its fun after reading other peoples’ build logs to finally be building parts I have seen before. By the way, I have no clue how that yellow protractor thingy is supposed to help me. I probably need to see someone who knows what they are doing use it.
Aluminum Angle Kit 6
My order from Wicks arrived today. Most of the items are for the Sonex workshop in February. My favorite item are these Andy aluminum snips–I’ve been referring to them as my man scissors.
Here are the rest of the items in the order with my steel ruler for scale.
Here is the vixen file along with the smaller, cheap file I have been using. I couldn’t find much information comparing the vixen file to other files I might own, but I figured if its required they must know what they are talking about. I tried it on some of my band saw edges this evening and it seems fantastic.
I did manage to get a few parts cut this evening.
Aluminum Angle Kit 5
Was losing my marbles this evening. I dropped the sharpie I use to label the parts and wasted a bunch of time looking for it. Then I left my cutting schedule that came with the aluminum between two pages of my plans without realizing it and spent a bunch of time trying to find it with no idea if it was on the floor somewhere or stuck in the plans. I did manage to get some parts cut though.
Aluminum Angle Kit 4
Seems like I’ve had a pattern of developing a new skill each day. This seatbelt attach bracket was my first “long” cut on the bandsaw (hehe… I know much longer cuts are coming). I used the fence to get a straight cut.
I’m starting to feel more comfortable making both mirrored parts. Did these cuts on the miter saw but will probably need to use the band saw for the rest. This part reminds me that I’ve been using a lot of trigonometry to calculate the cut angles–I guess most people use a protractor, but I don’t have one I feel is accurate enough. I can set the miter saw to a quarter of a degree with no interpolation. I mark the beginning and end of the cut on the part’s edges and I hit both marks each cut. I guess my calculator works (good thing I’m not stuck in radian mode).
This was my first “miter” cut on the band saw. I had hoped to use the miter gauge to help cut at the right angle, but the geometry of getting the part to the blade while attached to the miter gauge wasn’t working so I decided to freehand it. I drew the cut line and used the laser to help cut right down the line–I split the line in half on my first try. The second try wasn’t as good–I ended up off the line by a blade width, but some finishing should clear that up. Not sure if I like the laser–the reflection off the aluminum seems a little too bright.
Aluminum Angle Kit 3
Cut out more parts and started actually using the miter feature of the miter saw.
I assume the dashed lines in the plans indicate a hidden corner, so this drawing is showing what I would consider to be the bottom of the part. Update: I was reading this guy’s build log who made this part first and cut it the wrong way around, so I am reasonably convinced that I did it correctly.
I also made my first mistake (that I know about anyway). I’ve been measuring from the 1 inch mark on the steel ruler to get a precise measurement and finally cut an inch too short on my last cut of the evening. Maybe had I not made the mistake I would have continued working?
Aluminum Angle Kit 2
My parents got me a nice Dewalt 715 compound miter saw and a real aluminum-cutting 12″ 96 carbide tooth sawblade for Christmas. I decided to put this to use cutting the wing attach blocks which are cut from a 1″x1.25″ block of solid aluminum. I figure if the saw will cut this it will cut anything. Also, there is a 3/16″ beveled edge that had been worrying me as I have not previously had much luck with my band saw (I was tempted to do this bevel with the compound miter saw, but could not think of a simple, safe, and accurate way of making the cut).
A lot of builders seem to recommend using a wood-cutting blade on the bandsaw to cut aluminum, but I couldn’t tell if this recommendation is just to save some money or is because a wood-cutting blade is actually desirable. My experience has been wood-cutting and metal-cutting blades are priced similarly at Lowes, but the selection of blades that fit my saw is small. The woodcutting blade I tried had a kerf that is about 10x wider than the actual metal of the blade and seemed to be gouging its way through the metal causing a ton of vibration, leaving a terribly ragged cut, and cutting much slower than I believe a blade with a smaller kerf would have. Unfortunately the kerf width is not labeled on the packaging, so you can only eyeball it. I decided to try a metal cutting blade and haven’t looked back since–the cuts have been fantastic.
Here I have tilted the bandsaw table 45 degrees and set the fence for a 3/16 inch bevel. The desired cut path is drawn in using a black sharpie. The cut went great even though I was initially worried the blade might drift and there would be little I could do to correct for it with the fence in the way.
Here is a part after being cut to size on the miter saw and beveled with the bandsaw.
Before making these exciting cuts I cut a bunch of aluminum angle to size for various parts.