Very nice indeed. Finally a product worth buying a 3D printer for! Don't think so though. I'll just subcontract that work out to Caleb! Not surprised it fires hard. There's a nice length of smooth flow pressure reservoir between the interrupter and restrictor.
I have nice printer and more the happy to print some out for folks if needed and bring to Saranac in two week. They will be a nice bright Yellow as that is the current ABS filament I have. PM any interest
hrm once i get my printer working again this may get tested....... once i finish my yamato parts and kongo parts that i can't do until my printer is up..delta is a pain.
Update I’ve made several changes to the BIC to fix some errors and problem areas. First is the seat for the magazine cap o-ring. The seat was too deep to properly compress the o-ring, especially after it had been sanded smooth. For some reason I have a good seal on my prototype and this issue never came up. But when I went to build some more guns they didn’t fire consistently and the leak was obvious. A field expedient fix is to use two o-rings, which should allow you to use any versions already printed. Next I made an updated sander mandrel to smooth the o-ring area. Because I tend to squish the first layers of my prints, the bottom layer always sticks out a bit. So I reversed the piece so that the sanding surface is on top instead of the bottom, making the print more accurate. If the old version works for you, there is no reason to replace it. The next changes were to hopefully get rid of some problem areas, where poor bridging could result in the magazine being blocked. There was an issue on the last 180 degree turn and also on the feed into the breech. These problem areas became evident when I printed a BIC with some clear ABS, which didn’t bridge as well as my grey ABS. As the printer makes the magazine passages, it has to bridge over the passage at the trailing edge of the hole. If this bridge is straight, the printer does pretty well. But if the bridge is curved, the filament will drop down in the passage and possibly block the passage. This is why the top of the magazine passage is flat instead of curved. I’m pretty sure that the problem on the last 180 turn is fixed. I’m less certain about the feed into the breech. Whether a problem shows up is very dependent on the layer height. So I recommend looking at the output of the slicer to make sure good bridging is there. I have also found you can possibly fix some of these blockage problems. If you can blow a BB through the magazine with compressed air, but it will not roll through using gravity, try this: Put a slug of acetone down the magazine (I use a 1/8” ID tubing with about 1/2” of acetone) and immediately follow it with 3-4 BBs blasted through with compressed air. Do it a second time and then let the magazine dry completely before testing it. You can repeat this if it doesn’t work the first time. Next were a couple of changes to make the design more robust. I reduced the size of the hollowed out bottom so that there was room for more perimeters around the magazine pressure line. The original design only allowed for two perimeters, making this a place for a possible blow out or leak. I also moved the “BIC” letters from inset to protruding. This was to make sure the letters didn’t reduce the thickness of the pressure wall, a problem you can see in the picture above. As always I welcome feedback, positive and negative, on the design.
How have I never seen this before. It is perfect for the Constitutions! I simply MUST make some. Question - The basic design appears to be designed to fit into a small barbette. What size barbette is it designed to fit, and is it possible to get variants without the barbette (for triples, Constitution, etc) and with offset barbette (for arming a single barrel in a twin turret, with space for a dummy barrel on the other side)?
I think the BIC would work well in AOS, mostly because its compact size will allow them to be lined up side by side. For AOS it might work better to remove the piston and o-ring, making the gun into a kind of Arizona cannon. With the lower rate of fire you don't really need a piston and it would be a lot easier to set up if you don't have to tweak all those cannons. The gun wasn't made for a particular barbet size, the size was driven by the size of the magazine passage. The smallest barbette size is 1.5" PVC, and that will only hold one gun. I have posted both a left and right version, so two can be put side by side in a twin turret. Because of how the magazine load port is off to the side, I don't think a triple will be possible.
I was just looking at some of my Big Gun ships and I wonder how well this can be scaled up for 7/32" and 1/4" rounds...
I printed a few of these on a Prusa I3 clone using slicer and I'm having a hard time getting the ID of the internal passages to pass BBs though them. After drilling out the spring seat I was able to get pins into the vertical tube that leads up to the breach. A 5/32" diameter was the largest pin that would go through. I'm curious what should the ID be? I'm guessing 3/16" but, I'm curious if there was more clearance designed in already?
Hmm, do the bb's go through the mag but not the uptube, or is it all tight? Are you sure you're not over extruding?
All the channels are too tight. It does seem like it's over extruding but, cutting down the extrusion factor makes it not air tight. I'm using PLA so, acetone won't seal it up. Any ideas?
About 2 hrs. It makes nice circles : ) So I think I've found a combination of settings that will work better. I'm going to print a slice of the BIC to see how it does.
when printing on my i3 out of 3 bic one failed due to overextrusion. z-axis setting is important. might slow it down some or adjust your cooling fan speeds.
