Apparently most of the projects that I work on these days are somehow just destined to take far longer than I used to spend on projects in the past. So, continuing along in that saga, here we are, Satisfactory Update 8 released on experimental and I am eagerly awaiting it to come to the stable branch. I’m trying not to burn myself out by jumping back into the game immediately, as I know I will if I do. Instead I’m planning to burn myself out working on replicas from the game.
Shortly after I finished off the 3D model for this replica in my last post, I got most of the pieces printed off and was able to start putting it together and seeing if it all fit together correctly. As I’d realized in that post, this replica had some rather small parts on it, that were much more suited for SLA printing. And that was going to make for an interesting challenge considering I don’t own an SLA printer.
The majority of the model I was able to print with a 0.4mm nozzle on my printer. And the size and feel of it came out perfect, I like to think. But when it came to most of the other small pieces, I started to realize that 0.4mm was going to be a tad large for some of the details and shapes I was planning on printing next. And as much as I wanted to get it printed in SLA, I didn’t know anyone who had an SLA printer, and I just didn’t want to go commission someone online. I was too impatient… well…. not impatient enough apparently to wait on a 0.25mm nozzle to be shipped to me. I’d seen what 0.25mm nozzles for FDM printers could do and had wanted an excuse to attempt to try one out. This replica made the perfect excuse to purchase and try it out.
The nozzle was relatively simple to swap out on my Prusa, and I was up and printing again in no time. It was a bit different printing at a smaller resolution, and I had to wrap my brain around the fact that I would need more perimeters and more top and bottom layers if I wanted to get the same strength of print as with a 4mm nozzle. In the end though, I was stoked with how the parts turned out.
As was probably evident from the exploded view drawing in my last post, I broke this model up into a number of pieces to be able to print some of the rather challenging geometry. And while I did try to hide the seams as best I could, there was still going to be a lot of gluing and a lot of filling of seams to make the parts look like one piece. Both the finger guard with trigger hinge, and the trigger itself printed in multiple pieces and I used cut down brad-nails (1.5mm and 1mm diameter) to use as registration pins to align the parts. I also needed to glue the parts of the base together, however, I wanted to wait for that until after I’d painted them. I figured it would be easier that way to get into some of the smaller geometry when finishing the replica. The same idea went for the button cap and some of the details on the other parts of the replica too.
I was pretty stoked to see it coming together, even with having to reprint some parts due to clearance issues and tweaks to sizing. And with it coming together, I faced the next challenge of this replica design, finding a torsion spring that would fit the trigger. I knew from the beginning I wanted the trigger to be movable and to spring back into position. However, I was no good as determining what the right size and strength of spring I would need, let alone finding a good place to purchase them online that wouldn’t get me a 100 of these small springs (I really don’t want or need that many now, if ever).
So, I decided to attempt making my own. I realized that a torsion spring wasn’t all that much different from a tension spring in how it was wound up. And I had plenty of tension springs from the assorted box of them I’d purchased for other projects back in the day. All I had to do was modify the tension spring, unwind it a bit and clip it to size, easy, right? Well, that ended up being more challenging than I thought, and I discovered just how hard the wire can be to unwind and manipulate at such a small scale. I ended up clipping the tension spring I was modifying in half, and then slotting the spring onto an M4 or M5 bolt, just to hold onto it well enough and then use a pair of pliers to unwind it and straighten out a couple of legs for it as best I could. Then I had to figure out how many coils to keep to get the right force on the torsion spring I was trying to make, and then shorten the legs on either side in a manner that made them be small enough but easy enough to work with and hopefully not dig into the 3D print.
The number of times I stabbed myself with that wire, and with just how stiff and challenging to manipulate spring wire is… I swear, my hands hurt after gripping the pliers for the several hours I spent trying to get the spring just right, with the correct shape, number of coils, and then to get it to fit correctly into the replica. It’s in a rather tough to reach spot, and trying to hold it in place and then screw on the trigger to the hinge takes a few tries to get correct.
Anyway… in my last post I talked briefly about how I did my best to hollow out the model, locate electronics, and make it easy to swap out the battery. I was still of the opinion, even more so after printing it out, that all I was really able to be going to fit in it was a set of LEDs hooked to a small battery with a mini-pushbutton to turn it on. And even while I was printing things out, I wasn’t sure how I was going to go about fitting up the pushbutton in the print. I ended up doing a couple test prints to get the button just right and ended up going with a design similar to a set of print-in-place pushbuttons I found via Hackaday, by Marc Schömann.
What I was sure about from the from design phase, and was excited to see to see just drop right in, was the LEDs and battery. While designing the model in CAD, I’d done some research into the LEDs and what I would need for a battery to power them and had picked out the LEDs and the battery holder that I wanted. Through a very nice hobby website called Evan Designs, I picked out a set of Ice Blue, 5mm LEDs, and a CR2032 battery holder. Both the LEDs and the battery holder worked out great in testing. As much as I wanted to wire and solder everything up, I held off, knowing it would be best to wait until after I painted the model.
And as for painting the model, I figure I’ll save that for a Part 3 post. I have enough pics and plenty to talk about that this post would start to get a lot longer than I want. Plus it gives me an excuse for another post. So, look forward to that.
Jumping Ship 