Recently, I posted a thread asking about small wheeled horseshoe shooters. Now, I kind of want to make one. I was wondering what methods people used the shape their aluminum properly. Thanks in advance for the help.
We used a .063" 5052 aluminum bent plate, which bent easily by hand. We used tabs cut into this plate, which interlocked with slots cut into our shooter’s top and bottom plate, to keep the piece bent to a perfect arc. Here’s a few pictures:
We didn’t bend aluminum. We used lexan that we curved around our shooter. If you’d like, you can add on some kind of traction-paper or paste to the curve to give it more spin than ours had, but ours works just fine smooth.
The lexan was backed by aluminum standoffs to prevent it from straightening out, and it worked perfectly.
Good luck!
We achieved a performance gain when we switched from traction backed to smooth.
I’m sure there are combinations of variables that cause a tractioned setup to work better, but or our specific setup smooth was better.
We tested this over a range of compression for both, so it wasn’t just the compression difference. I think it’s because our flywheel had very little inertia, and that “locking” into the disc with high traction probably dumped a lot of energy.
Shooters are black magic.
We used a piece of .063" 5052 as the curved piece that the frisbee traveled against. To attach this to the top and bottom plates we put tabs (straight) no bends on the curved piece and holes in the top and bottom plates for the tabs. Everything just “snapped” together, and then we threw a few screws between the top and bottom plates to prevent the tabs coming out of the slot.
This was our “simple” solution. This requires some tweaking of a bent sheet metal part in CAD to get to work correctly. Although we were successful on the first part manufactured, the tolerances were about the tightest we could get them. I’ll dig up the numbers later on.
We lined the wall with a nonabrasive 3M friction tape; not like a sandpaper.
We wanted to send the assembly to GEICO to let them know that Tab A does fit into Slot B.
ha, oh my. I thought you were making something to shoot horseshoes. Glad to hear it is just your shooter that is shaped like a horseshoe
In 2012 we wanted to make a curved shooter. We took a sheet of aluminum and held it against a trash can and hammered it around it. It didn’t work and we ended up not using it, but that’s probably because we used a fairly thick sheet (about 2mm. Well not exactly thick, but way thicker than you need). If you use a thinner sheet it would probably work well.
Successfully bending aluminum (so you can shoot horsehshoes? :rolleyes: ) depends on several factors:
- The type of aluminum: Some alloys do not bend well, others bend easily, and some just break. Find the right kind.
- The thickness: Some alloys can be bent if thin enough, but thicker will crack. Again, find the right alloy.
- The bend radius: tight bends are harder than broad bends (say, 24" diameter). Broad bends are easier by hand than tight bends.
- For a precision bend, you use a roll bender. Even Harbor Freight sells a cheap one. You can even make one with some effort.
Our first horseshoe prototype shot about 5 feet, due to it’s terribly made curve. If you are going to manufacture your curve, take your time and do it right.
If you plan to use a pneumatic wheel (like we did), plan for at least a 1/2" of expansion at 5000rpm. We ended up only being able to spin ours at 1/2 speed because of this phenomenon.
We used a 3/16" piece of aluminum (I know it wasn’t 6061, I believe it was 6063) and asked a local metal fabrication shop to roll it into the right shape.
The first place that we asked to do it charged us $50, and they did it wrong, even though we left them a (dimensioned) drawing. From a phone call that we had immediately after we picked it up “Well, I didn’t know what a radius was…” I think that they refunded us for the “labor”, but they still ate our metal (6061). The second place told us that we needed a different alloy, and they gave it to us, in addition to rolling it.
If you have access to a welder, weld strips/tabs to the back, but be careful not to warp the curve.
Good Luck!
We used around 1/2 in plastic for the curve instead of aluminum and used the extra thickness to mount an overhang keep the frisbee in place while contacting the wheel. we bent it using cinder blocks on each side to make the arch and heated it with a heat gun to make it keep the shape. it worked well, but unless you need the extra width for something it would be easier to do aluminum.
+1
We did pretty much the same thing.
While this doesn’t answer the original question, I’ll share anyway.
We are fortunate to have access to a 3D printer, so when we had determined our favorite shooter radius (empirically), we modeled a template (in 3 interlocking sections to fit in the printer envelope) and printed the contour we wanted. The template was applied to a rough cut piece of plywood and run across a router table with a piloted trim bit. Voila! The finished piece was rigid, lightweight, and had a consistent radius. I must admit I went a little overboard with the stain and polyurethane, but it’s GOT to look good, right?
We used the same method… I highly recommend it if you can relatively accurately cut the slots in the bottom and top plates. If you have a sponsor with a laser cutter, it’s trivial. I suspect careful use of a jigsaw could be made to work also.
It sounds like some people pre-bent the curved backplate… although this works, instead we just used a piece of 1/8" lexan (could definitely go thinner - our backplate was overwhelmingly rigid).
We also found a slick backplate to be preferable to a grippy one. Our shooter wheel had quite a bit of “squish” to it though, so perhaps a more rigid shooter wheel combined with a slick (and rigid) backplate would be too unforgiving of varied Frisbees? If you haven’t yet picked a shooter wheel, I’d recommend the one 1114 and 2056 used this year. Sounds grippy, squishy, and incredibly wear-resistant.
I like this method, and I agree that you should consider other methods besides bending aluminum. My team used a bunch of 1/4in abs laser cut into the shape of the curve that we wanted, then stacked them on top of each other (we did this not only for the shooter, but for storing frisbees too). You can see it better in the attached thumbnail.