[ImperialWalker]

Hey All,

Building a trap has always been one of those bucket list things that has been gnawing at me ever since the late 80's when attempts were made using lego, cardboard, and even paper mâché. With the purchase of a new 3D printer, the ability to see that dream come to fruition has finally come.

Part of what convinced me to purchase a 3D printer was seeing the Charlesworth Dynamics trap featured on Tested a few yeas back. I quickly downloaded all the files where they sat, just waiting to be built.

With the last of my orders trickling in for my GB trap, I figured it was time to get started. This thread will be a bit of a documentation / review of the kit and the process. It is important to note that my criticism and thoughts may sound harsh and direct, but it is done with the upmost appreciation for what Sean has done.

Also keep in mind that my methods and ideas are often a little... err, outside of the box so don't be surprised if I go off on tangents that leaves everyone scratching their heads in confusion.

I hope that this helps others and sparks some conversation along the way. I appreciate any feedback and thoughts as well, but I ask one thing. Be honest, be harsh. I don't need you to hold me tightly by the fireplace while you whisper how proud you are of me. I want honest and helpful criticism to make my trap the best it can be.

With that little intro out of the way... let's get started.

[ImperialWalker]

The Goal

My goal is to create a trap that would have been seen somewhere between Ghostbusters 1 and 2. A trap that is mostly the style from the first movie, but with elements and upgrades that would have happened in the time before the second. A hybrid if you will with a heavy influence to the first version.

While I am 3D printing the majority of parts, I opted to use real world parts where available. For example, I have an order of knobs from this website on the way. I also purchased the deluxe kit from Charlesworth Dynamics (review to come later) which provided some of the actual parts used on the traps.

The CD (Charlesworth Dynamics) trap is designed to incorporate lights, sounds and smoke. I will be mostly following that plan, but after seeing a few other traps people have created, I have decided that I want mine to more closely resemble the movie version. Therefore I will be doing things a little differently in terms of lighting and sounds.

The hope is that I can make it as accurate as possible within the scope of what I'm trying to achieve.

[ImperialWalker]

The Hose

Going off script right off the bat I decided to start with the construction of the hose. I figured that it would be a good starting point to get brush off the soldering cobwebs and to tackle something I could complete in a weekend.

I started out by following the directions and disassembling the female connectors. The first step is to cut out some electrical tape to isolate the metal spring inside from the casing.

I tried using the method shown in the directions, but wasn't happy with the result.

I tried modelling and 3D printing an insert, but even at the finest quality my FDM printer couldn't print a wall thin enough to work. I ended up printing a template created in Illustrator which I taped on top of electrical tape stuck down to the cutting mat. I could then get accurate inserts with notches cutout to allow it to curve up the sides a bit.



After fiddling with this a bit I got it perfect. Which brings me to my first criticism.

...

Connectors and Plunger

The goal here is to isolate the metal spring from the housing allowing the signal from the peddle to work. CD has opted to use glass tape, but recommends electrical tape or heat shrink as well. The problem is that the build order of this means that in the next step you'll be applying huge amounts of heat to the brass connector. This heat, as you can imagine will mess with the heat shrink and electrical tape.

I found this out the hard way as I had to go back and redo the electrical tape after soldering the wire. The build order really should have the electrical tape being the last step.

That said, I also think electrical tape/heat shrink isn't the best solution. If the goal is to isolate the spring, I think a much easier and more effective way would be to apply a non-conductive coating to the spring itself. A coating of liquid electrical tape or rubber would not interfere with the movement of the spring, but would make it so much easer to apply.

The next step is to remove 1/16 of this part called the plunger. It is a tiny metal part that attaches to the spring. The idea I believe is to remove 1/16 of the metal plunger and then extend a 1/16 brass rod from the male connector to connect with this.

Now, I only sort of tested it, but I am not convinced this is going to work that well. The reason is that the part that you take off results in a very small surface area. This means that when the brass tube comes into contact, it must find this little ridge and maintain a strong connection.

These connections are also designed to spin. This is a good thing as it allows the trap to spin around on the hose reducing pressure and keeping the hose free of twists. In one of my initial tests the brass rod slipped to one side not allowing the connectors to spin freely. This could put a lot of pressure on the parts and ultimately cause failures.

My suggestion would have been to either completely remove the fin on the plunger (and extend the brass rod), or increase the surface area of the top of the plunger using another method. This would create a flat, large surface area for the brass rod to find.

Time will tell if this will hold up.

...

The Wires... Don't cross the streams

The instructions call for soldering a blue wire to the plunger and a black wire to the connector.

Now, perhaps I am totally screwed up but, it appears to me that CD has this completely mixed up. I've attached a diagram of what the directions call for.



Now, again I might be looking at this incorrectly, but it appears that the wires are reversed along the inside of the tube. Not a huge deal as a wire is a wire, but it had me super confused after I tried troubleshooting a connection only to realize I was working on the wrong wire. My perfectionism makes me want to go back and rewire it, but I'll leave it for now.

As you can see from the diagram above, the directions call for soldering a wire to the barb of the female connector. This is no easy task and brought me back to my days in art school when I got the brilliant idea of soldering together a giant brass lantern. The issue is that to avoid a cold weld (a weld that doesn't actually adhere to the metal) you have to heat the part. The part of course won't just heat up in one spot and will dissipate the heat to the rest of the object, the vise, the leather you're using to hold it in the vise and everything else.

What I don't like about this is that you solder a small wire to the end of an edge, where there is the most amount of flex and strain on the hose. This came back to bite me later when I attempted to insert it into the clear tube and my wire broke off in the process.

I should have went with my gut feeling and dealt with it then and there.

I think a better solution would be to take the wire and wrap it around one of the upper parts on the barb and solder it there. Then, taking a heat shrink tube, cover both the blue and black wire, as well as the barb and solder point.

After shrinking the tube this would lock both of the wires in place and create a strong, flexible stress point at the end of the barb. It would also hold the wires onto the barb not allowing them to pull out as easy with stretching that likely comes while rolling out the trap.

This is really bothering me because I am concerned that black wire will eventually snap in the tube requiring me to take most of it apart and heat up the brass which has already discoloured due to heat.

...

We Be Tubin'

With the connections made, it was now time to put the wires in the tube.

An old electricians trick is to use a vacuum or your mouth and suck a piece of string through the tube. Then, you attach the wires and pull it back through. Clever!

The instructions call for slicing the tube lengthwise and manually feeding the wires inside and I wanted to avoid this if possible. The less chance of moisture, mud, dust, and such getting inside the plastic tubing the better.

Hmmm... The problem is that the tube provided in the kit has a very small inner diameter. This means that while the wires do fit, they cannot be pulled through as the friction becomes so great after a few feet that it is impossible to move. I tried doing one wire at a time. I tried different rigs, but in the end I ended up slicing the tube as directed.

To do this, I created a simple little jig.

Using a piece of plastic tube the same diameter, I poked a knife through just enough so it would slice one side. I then taped that knife down to the table.



I could then feed the tube in and pull it the entire length. What I like about this method is that the tube naturally twists meaning that the cut is spiralled along the entire length meaning that it does not easily buckle open.

The inner diameter of the tube once again became an issue when trying to connect them to the barbs at the two ends. To fit them on the ends the tube needs to be sliced, but this creates a really weak connection due to the tube only covering about 3/4 of the diameter of the barb.

Once taped and zip-tied it seemed to hold, but I think this could all be avoided with a more appropriately sized tube.

...

Eventually you'll need to connect the wires from both sides. This is just a small nitpick, but while the directions show a staggered connection of the wires (meaning they don't connect at the same spot), there wasn't any little notes to point this out. I wasn't thinking and I connected the black and blue wire in the same spot, only to realize that they wouldn't fit into the tube with the addition width of the heat shrink.

I ended up having to redo one of the wires further along so the connection points were not in the same spot. Not CD's fault, but one of those quality of life notes that would have saved me a half our.

...

Fosters Male Connection

To shield the connector from electricity, a 3D printed part is inserted into the Foster connectors. Then, a brass rod is inserted, cut to length and soldered to a wire. This allows the connection to be made with the plunger inside the female connector and then through the tube.

The directions say to solder a wire to the end of one of the brass rods, then insert it into the 3D printed part. Then, when 1/16 is poking out the top, glue it in place add some heat shrink and call it a day.

Again, this doesn't sit right with me. Not only am I obsessive about cable management and clean looking parts, but I didn't like that it caused a stress point with uncovered wire. The reason for having to use heat shrink is because once the wire is soldered to the end, it becomes too bulky to fit into the 3D part.

To solve this, I took the rotary tool and a disk and carefully created a notch at the end. Then, I filled this with solder and laid the wire inside. This resulted in the wire coming straight out the back of the brass rod. With a little sanding and scraping with the hobby knife, I was able to create a clean, strong connection.

The best part, is that it could now be inserted into the 3D part and glued in place leaving the wire to come out the end. I think it not only looks cleaner, but most importantly is not stressed.



That said... I am concerned about this part holding up. When the male and female connectors are inserted into each other... Hmmm, err... Well, the little brass rod presses on the top of the plunger and spring. I suspect in the normal operation this pressing action opens the valve. In this case it keeps the two connections tight together. The concern I have is that the spring, which is already super compressed will not have enough give and will push the pin and / or the 3D printed insert out of the Male Foster. CD recommends some glue, but in my experience when you introduced two immovable objects then something has to give. The spring and brass rod won't, but the fragile 3D printed part and the glue likely will.

If it ends up becoming a problem, I may end up replacing the spring and plunger and opting for a connection with larger contact points and a weaker spring. Something that will keep the pressure together for a good connection. Or... I might just permanently wire the thing up as I'm not sure when I would remove the hose anyway.

...

Result

After finishing up the final steps I put it together, taped up the ends to fit the GB1 style and put on some zip-ties. I gave it one last test with the multimeter and it seems to be functioning as intended. It needs some weathering of course, but I think it turned out quite well.

I am still concerned with the connection points and how they'll hold up over time, but hopefully they don't become an issue.



...

TL;DR

I think overall this part of the instructions were easy to follow and accomplish. There does however seem to be some mistakes in the directions which could cause issues down the line when troubleshooting. Some quality of life notes in the instructions would make things a little more clear in some parts as well.

I think the solution to making the pedal work is really clever and full credit to Sean for coming up with this solution. I would like to see a few improvements made to assure the connections are more robust.

One of the biggest things I would like to see changed is the diameter of the rubber tube. A thinner one might not feel as hefty, but it would go a long way to making the process a lot more user friendly. It could also mean that the tube does not need to be cut, which would help keep out moisture, dust and other things that could work themselves into the tube and mess with the wires.

Anyway, I had fun!

Three Venkmans out of 5

[ImperialWalker]

You can’t Handle the truth!

When I was young and attempting to create a trap out of LEGO and cardboard, one of the failure points was always the handle. No matter what it would always bend or break off. This of course lead to many LEGO traps smashed into a hundred foot murdering pieces.

When I started building this trap the second I looked at the directions I knew the handle was going to be one of those trouble spots. I printed the handle part with a 90% infill just to be sure it wouldn’t snap (I have no idea how heavy this trap will be).

I then then attempted to thread the socket screw into the hole. As expected it is really difficult to keep downwards pressure for that long of screw. The hole in the model is also not very long and I am sure I bottomed out. This caused the entire thing to be stripped. I considered gluing it, but it just didn’t feel right.

The handle is basically attached by one small screw with tiny threads, on a single pivot point that wobbles because the holes in the aluminum handle have larger tolerances. I thought about how I could replace the small screw with a hefty one that would go well into the handle. It occurred to me that most of my IKEA furniture has what are called Dowel/barrel Nuts. They work by being inserted into a hole that crosses the bolt. When the bolt is inserted, the nut tightens inside.



1/4-20 1/2" Barrel/Dowel Nut

However, the problem was that the 3D printed model doesn’t have a hole for the bolt, or the nut. So, the next thing was to adjust the 3D model to allow a bolt to pass through and connect with the nut.

10 hours later it came off the print bed.

The bolt I used is a — 1/4-20 x4 Stove Bolt Round Socket Head

This gave me the length I wanted and basically created a metal core in the handle.

The problem now was figuring out the handle. The head of the bolt is much too large to fit through the existing holes, and I was concerned that without some kind of support inside the bolt wouldn’t sit square and put uneven downwards pressure on the handle. I also didn’t want the handle to be able to spin or wobble at all as I felt this would eventually lead to it failing.

So, once again I turned to the 3D printer.





I designed a little insert that holds the bolt in place and distributes the downwards pressure evenly. So far, so goo… well, of course. I needed to widen the hole to 1/4” and take a slot out of the aluminum tube to allow the bolt to slide into place.



With the bolt in place and tightened the handle was now feeling really sturdy. Now we have to deal with the original screw and the cap. I thought about how I could do this and realized that if I combine the cap and the screw that they would not only slide into place and further secure the bolt, but when the screw was inserted it would lock the cap in place allowing for it to be removed later if need be.







The original socket screw is obviously way too long now and so I will have to replace it with a much shorter one… which I hope I can find, or I’ll have to chop off the old one and hope that works.



Maybe this is overkill and maybe I could have just lathered epoxy on the original design and it would have been fine, but I never wanted to experience the momentary dread as the handle snapped off and the trap fell in slow motion to the floor. I am confident that this will be sturdy and gives me peace of mind. If you would like to use this with your trap, feel free to download the files on Thingiverse here.

https://www.thingiverse.com/thing:4747034

[Couture]

You just came up with a great solution to a problem that I've been worrying about with my build! Years ago I bought a really beautiful trap and the handle broke off in that exact place from hanging the pedal on it while costuming. I've since been super weary of that stress point and worried about how I was going to reinforce it on my printed trap to avoid it happening again. I'm definitely going to go in this direction.

[ImperialWalker]

Nice! I hope it works for you and you never lose another trap due to a handle mishap.

[ImperialWalker]

Pedal Remix

This part of the build has been... interesting to say the least. After a week of printing, the pedal base was the last thing that I needed to print.

Knowing that it would take some wear and tear and because I wanted it to have some bulk to it, I opted to print it with a fairly high infill. This of course increased the print time to about 15 hours. Little did I know that 15 hours would turn into days.

Living on the West Coast means that a lot can happen weather wise in 15 hours and where I live ocean storms often roll in causing trees to fall and the power to go out. This happened not once, but twice as I was attempting to print this part. Needless to say, I was unimpressed. Not only that, but I was super unimpressed that the power outages happened at the same time in almost the same layer of the print.

Eventually I got a near perfect print and started putting it together. But...





...

Not Feeling It

I had the entire pedal together, and no offence to CountSpatula but, I just wasn't feeling it. After researching the pedal more, it started gnawing on me that there were so many inaccuracies. I also didn't like that it wasn't very detailed.

Some of the things that were bothering me:

- The extension on the left side (small box) was missing

-I understand the designer logo being on there and I appreciate that he tried to hide it under the vector plate, but I could see it and it made it feel like a toy.

- The screw holes on the bottom to keep the plunger on didn't seem accurate to me

- There was no metal trim on the front and there was no separate aluminum bottom

- The acorn nut also was inaccurate and needed to be replaced with a bullet latch.

- There was no cutout in the centre and the tubes just kinda went into holes.

- The hinge sat too far back and hung off the edge

I attempted to salvage it by filling the designer logo and I was going to try and scribe in some lines to make it appear like there was attached metal parts, but in the end I just felt it wouldn't look how I wanted.

...

Pedal to the Metal

I felt like the only way I was going to get it more accurate was to make it from scratch. Now, I was a little limited in that I had already drilled all the holes for the project boxes, so I had to steer towards the GB2 pedal.

Unfortunately the Countspatula design in its attempt to be a hybrid between GB1 and GB2 has created a situation in which it is very difficult to commit fully to either one.



I kept many elements of Countspatula's design as I needed the electronics and plunger to work as before, but I used dimensions from the information I found in these forums. The following modifications were made.

- Removed designer logo (sorry Count) and added the centre cutout.

- Adjusted the overall dimensions to be more accurate

- Added the GB2 extension on the left (small project box) side

- Added the wrapped metal to the front

- Added a faux aluminium plate to the bottom with "nubs" for the faucet feet

https://www.homedepot.com/p/DANCO-5-8-i ... /203193530

- added a hole for the Bullet Latch

- Moved the hinge holes up so it sits closer to the movie version



...

Bullet Latch

The bullet latch was a part that I just couldn't source. Well, to be more accurate, I could source it but for some reason it was impractical to get shipped to Canada.



Countspatula offered to sell me his which I super appreciated, but unfortunately I wasn't sure it was the correct model and passed on the offer. Instead, I opted to simply model it and print it with my new Elegoo Saturn resin printer.

Thanks to the help of WESTIES14 I was able to model it up and with some additional help from another forum I was able to get it as close as I could.

I printed a few and was happy with the result. Feel free to download and print your own.

https://www.thingiverse.com/thing:4772769



...

New Pedal

While I modelled the front metal piece to be 3D printed, I wanted actual aluminum to give it a bit of strength and to allow me to eventually weather it.

To make sure I had the holes lined up, I cut the pedal base model which gave me a template to work on. Starting on the right side I drilled the holes which I secured with screws allowing me to make a nice crisp bend around the corner. I continued this until it was all the way around.



Once that was competed I put it all back together. I replaced the FDM Banjo with a resin one, added a newly printed Bullet Catch and added a resin resistor to the middle.

I plan on working a bit more with the middle part to make the tubes connect logically and like the film, but for now I'll leave it there.

If you want to print your own, feel free to head over to Thingiverse ( https://www.thingiverse.com/thing:4780037 )

[Darth_Egon]

I just wanted to say thank you for giving us your files for the pedal base!!! I printed them out along with your bullet latch to finish my trap build!!! Here it is in action

[ImperialWalker]

Awww, man!

That warms my heart!

I am so glad that worked out for you! The pedal and trap really look fantastic.

Well done.

[ImperialWalker]

Pedal Electronics

Having completed the prints for my pedal it was time to start looking at some final details. I'll be updating this post a bit more when complete, so check back.
...

Tubin'

In the original CountSpatula design the red and yellow tubes were attached by press fitting them into two holes modelled into the base.

When I remodelled the base (post above) I cut the middle part out to be more in line with what was seen in the movies. The issue was that now there was nothing for the tubes to actually attach to.

While looking at the reference material, others had pointed out on the GB1 trap, there seemed to be a resistor ( same as on the side of the trap ) that the tubes were attached to.

In CountSpatula's files he does include a nicely detailed resistor, which I initially resin printed.



I drilled out the centre hole and inserted a metal rod to attach the yellow tube.

I then realized that I didn't really have anything for the red tube... hmmm...

...

Artistic Licence

For the most part I have been trying to stick to as accurate as possible, but in this case I decided to take a little bit of artistic liberty. Why? I dunno...

I wanted the red tube to have somewhere to go that seemed practical, while also keeping it in the right position. So, I headed into Blender and started adding random greeblies to give it some subtle texture and tech looking stuff.



The idea was to keep the resistor as the main focus, but have some detail (to be painted black) that would, if looking close enough give a bit more detail instead of a flat bottom.

I also wanted it to be removable in case I decided at some later point it was a little much. So, with an excuse to use the resin printer, I printed out a few versions.



The hope is when painted the same flat black as the pedal, with a few subtle dry brush highlights it will just give a bit of interest without being too obvious.



...

Issues

I am going to make the file available for download if anyone wants, but I have to fix some issues.

First, my resin prints are super brittle. I have no idea why, but these prints are warping post print and eventually become so brittle they snap. I am still trying to dial in my printer settings.

The model is also not manifold (meaning it has holes and issues that could mess with the print). I need to sort those out, but when I do I'll make it available for download.

Again, I realize it isn't accurate, but I think it's kinda fun.

[Sea_Marshall]

great insight here. I agree with your assessments, even with as little knowledge as I have on the trap. I found similar issues and decided to scratch build the pedal base too. Thank you for the tips. Really helpful to understand what I'm looking at.

[ImperialWalker]

Holy Smokes That Is Overkill!

I admit it. This next section was almost purely overkill. For me this project is as much learning to 3D model and use my 3D printer as it is building a trap, so I've been looking for any excuse to do both.

The other reason is that for some reason I can't stand a rats nest of cables. The inside of my computer and the back of my desk are two examples of places where I take cable management very seriously. My wife on the other hand does not care and her drum kit gives me anxiety!

The original plans call for velcro, hot glue, and a sort of "jam and make it fit" solution. This made my eye twitch and so I started looking for possible ways to clean everything up and make it look really organized.

...

A Mini Containment Unit?

What you are looking at below is the internal structure I built for my trap. I'll break down each section and give you some insight to my rational.



...

Battery

The first thing I started with was the battery. I wanted the battery and the tubes to be held in place so they didn't rattle around, while also having cable management slots to keep things organized.



This took quite a few prints to get right as it became more and more finicky to deal with all the tubes and battery. Admittedly the structure itself actually caused a lot of grief as it took up so much room that things began to fit worse than had I just shoved everything in there as the plans originally called for.

Eventually I got it sorted and it held the battery as intended, wires routed great and the tubes seemed to work... but once again after another print, things didn't go to plan.

The issues were:

• There are screws that pass through the bottom that need to be screwed in before the battery is installed

• The space where the E-Cigs pass through needed to be wide enough

• The battery wires needed a place to go which I forgot about

• The tubes would not feed properly without kinking or putting pressure on the rest of the trap

• The top of the battery holder could not be installed and had to be split in two parts

• The switch and light were bumping into the tubes

After many, many versions (35 to be exact) I was able to get a final design that worked pretty good. It does take a bit of effort and a specific order to get it all in place, but once all the screws are attached and such, it was working pretty good.



This took a lot of effort (way more than it should), but I am ultimately happy with the result.

The tubes are organized, the wires are neatly hidden, and the battery is contained and has a low centre of gravity. The only thing I would like to do is change out the red tube which is a fuel line tube. I cannot seem to source the same type of tube sent with the kit. Only Nylon and silicone are available locally and they kink too easily.


...

The Power Rail of Love

In the original plans, CountSpatula suggests using velcro or tape to attach the Power Rail and the Bargraph board. As I stated above, I wanted to avoid velcro and tape as much as possible and create something a little more designed.

To do this, I basically just modelled up a holder that would fit over the screws and click into place.



It was a pretty straightforward part with only one or two prototypes to get it right. The result is that I now have the Power Rail screwed down which holds the Bargraph Board in place.



...

Taking the Metro

Again, the original plans called for velcro when mounting the Uno Metro. This of course is so that it can be easily removed if needed to reprogram or deal with connections. This may bite me in the buttocks later, but I wanted a more permanent solution that would keep it from moving around.

My other goal was to hopefully cut down on light bleed from the gaps in the model. The wheels have large gaps that I was concerned would allow light to leak out onto the ground.



Originally this was a separate piece which went through a couple of iterations for placement and height. Eventually, I opted to join it with the Smoke Pump holder which helped to create a nice solid part that actually squared the trap a bit which had naturally warped a bit.





This worked as intended which allowed me to screw it down and keep it level and solid. I hope the covering on the wheels will keep light from leaking out, but we'll have to see.

...

Good Vibrations?

One of the biggest reasons for such a drastic deviation from the original plans is the smoke pump. Through no fault of anyone, the biggest tell that this is a prop is the sound of the air pump as it buzzes.

The original plans have a part that holds the pump in the air and uses a little rubber strip to try and dampen the sound. Unfortunately, I think that this not only results in the pump transferring the vibrations to the trap, but because it is sitting in the middle of a hollow box, I think the sound is amplified.



I wanted to see if I could cut down on the noise and thinking back to when I owned a fish tank, I remember the best solution was to encase the air pump in foam.

The idea was that if you could keep the pump from touching anything but the foam, that the vibrations would be dampened and cut down significantly on the noise.

To do that here, I would have to reorient the pump and try to make it all fit together with everything else, including the E-Cigs. As you can see from the image above, the concept was to create a cavity where the pump could sit. This would be packed with foam allowing only the hoses and wires to come out.

Easier said than done.



The first issue was that prototyping this was super time consuming. Each print was 20+ hours so it was super frustrating when I tried to put it together only to find something didn't fit correctly.

One example was the lid.

The original idea was that the tube would come out the back, curve up and attach to the bottom of the trap as per the original plans. This did not work at all as the orientation and height of the pump made the curve of the tube too extreme causing kinks.



I then tried to have the tube connect to the lid. This would allow the air to pass through a molded tube inside and then connect to the hole in the "roof" of the trap.

It actually worked really good... except that because my trap is slightly warped due to the nature of PLA, the forces placed on the parts caused the trap to be twisted. This caused issues with fit of other parts and screws. The other issue was that the PLA didn't have the strength on the connections due to it only being able to print two walls.

This caused them to be easily broken if any sideways torque was applied. This left me stranded and I had to take a week or so to think of a solution.



As I was looking at some fish supply places for tube, I came across some plastic connectors. They were strong and would easily hold the tube without breaking. They would take some modifications, but I was sure I could get it to fit.

I modified the design so this connector was no longer attached to the lid and could freely move to accommodate for any warping. I modelled the connector to accept the plastic fish connectors with very small tolerances so it was a very tight fit.

It worked great and allowed me to put the trap together without issue.





Everything seemed to be working. The pump was held in place nicely by foam. The tubes were routing as intended and could be installed and removed without issue. Everything was looking good...

Until...


...

Full Roaming Vaper

I went to put everything together and the E-Cigs didn't fit. The angle I had chosen for them put them way too high in the battery compartment and the tubes would not work without a lot of strain.

This almost made me chuck the entire thing out in all honesty. The amount of work to backtrack to redo the entire thing seemed like it just wasn't worth it and I put the whole thing on my desk and went on to another project.



I knew I had to fix it, so after a few hours and a very... very long print later it seemed to work. I was able to slide the E-Cigs in quite far without them interfering with anything. They could be removed without issue as well for refilling and charging.



...

Yes... it is completely over engineered in many ways, but... it accomplished the goal I set out with, which was to create what I think is a cool looking, but practical way to manage the internals.

I printed a bunch of these little wire holders as well. I will glue these inside the trap in places to help direct wires and keep them organized.



...

So there we go.

[ImperialWalker]

Springtime!

One of the things I've tried to do with this trap as I build it is try to foresee potential points of failure. One part that I noticed early on was the spring on the foot pedal.

The CountSpatula plans use two 3D printed discs that are inserted into the top and bottom of the spring tube. The bottom screws into the base while the top is glued/taped to the vector pedal.



Little rings around the discs are designed to "bite" onto the rubber tube keeping it in place. Not a bad design, but as I took the pedal apart a few times I noticed how easily it would come disconnected allowing the vector plate to swing out.

The second concern I had with this design was that there was no tension on the vector plate causing it to be pushed up in a fully extended position. To me this put the angle of the plate way too steep and high.

I wanted to find a way to solve both of these concerns, while still keeping it accurate as possible.

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Reference Trap

It seems the original designers also had to find a way to keep the vector plate from swinging open while also keeping the pedal in the right position.

Looking at the original pedal a wire can be clearly seen coming out of two holes.



It seemed to me that they used a wire that looped around the vector then connected to the wood inside. Then some kind of internal stop was installed to only allow the pedal to be compressed a certain distance.

Using this as inspiration, I looked for a solution that wouldn't require a lot of redesign.

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The Design

Obviously the first concern was that my wire couldn't simply go straight down the middle. This is because of the micro switch that controls the entire trap.

I had to find a way to redirect the wire.

The second issue was that this couldn't be a permanent solution. I needed to have it be easy to take apart to allow for adjustment, painting, etc.

So, I knocked it around in my brain a bit and came up with the following solution.



The idea was to use the same discs as CountSpatula, but recreate them to allow a wire to latch onto the bottom, feed up and through two holes in the top, which would loop around the vector like the original, and then come back down the other side.

This would allow me to set the height of the vector, keep the wire out of the middle, while also holding the vector down in case it was bumped.

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Wire Tap

The first thing to sort out was what kind of wire to use and how to get it to lock into the 3D printed part.

I tried a few different kinds such as picture wire, fishing line and speaker wire. In the end I went with coated aircraft cable (braided cable).

This gave me the flexibility I wanted while still remaining very strong. The original didn't use coated wire, but I wanted to avoid rust and fraying.



To create a stop I headed to Home Depot where I found aluminum crimp ends (can't remember the technical name). Using a crimper, I went around and around until it was tight on the wire.

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Vector Plate

Having printed the new discs and prepped one side of the wire, it was time to drill the holes in the vector plate. This terrified me because screwing this up would mean a lot of hassle getting a new one. I was so happy when I nailed the hinge holes and I didn't want to screw up now.

To help make things easier I designed a little jig.



The idea was that if I could get the bottom disc lined up, I could slip this jig over the vector plate and the drill holes would be exactly where I needed them. Any misalignment would mean the wires wouldn't fit into the disc preventing it from sitting flush with the bottom of the plate.



I printed it out and after building up some courage I drilled two very small holes. I figured if I messed up, two small holes would be easy enough to fix.

In the end it turned out and after drilling larger holes, I fed the wire through for a test.

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Whoa... not so fast

No, it wasn't that simple. Turns out that trying to feed a not so flexible wire through small 3mm holes that turn 90 degree corners is no easy task. I suppose anyone who has tried to feed a cable through a pipe in their home knows this struggle.

I tried like a billion times to hook it with a bit of string, but it was just too finicky. In the end I ended up reprinting the top disc which had small internal pockets that I could push string into. Then as I pushed the wire through I pulled the string allowing the end to pop out.

It was really finicky and annoying, but it worked out.



It was also a little troublesome to get the wire the right length on both ends, while trying to feed it through the 3D printed part. The top disc only allowed the wire to pass through when it was at a certain angle. Any other position and it would lock in place.

This made it difficult to easily adjust the wire, but I plugged away at it while watching that old Ewok movie and eventually got it in place. I did also opt to use Gorilla double sided tape on the underside of the top disc. It seemed like it would have stayed, but I wanted an added layer of strength.



I screwed the bottom disc to the base as a test and it seemed to work great. When the pedal was pressed the wires would slightly bend, but didn't interfere with the switch in any way. They would then straighten back out and hold the vector in the correct position.

Oh... one note about this photo.

The original plans have the switch attached to a 3D printed upright (seen in the middle). However, only one is used. You can see that I remodelled it to have two. This is because having the stop on only one side meant that as the vector came down it would twist to the side without the stop.

I really didn't like this as I could see it torquing my entire pedal and putting strain on the hinge screws. So, I modelled extra holes and extra stop for the other side. Now, when the vector plate comes down it stops evenly on both sides.

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Tubin'

Everything seemed to be working as planned so I unscrewed the bottom disc and installed the spring tube. This took a little bit of work as I had to compress the tube fully to slip the wires into the disc. Once that was done though, all I had to do was screw it back down and give it a test.

While a little stiff, it works exactly as I wanted. I'm happy with this little tweak and am now confident that if the vector pedal gets knocked or hooked, it won't rip everything apart. It also has really satisfying "click" now.

[ImperialWalker]

Catching Ghosts

Just a small update. I've been busy priming and soldering so there haven't been many things to share. I added some detail which I'll post later, but today I want to focus on something I've been meaning to do since day one.

I've wanted my trap to have the movie capture sound, but I also wanted versions where it sounded like different ghosts were being captured as well. I wanted this to be completely random so there was always a little bit of variation when a ghost is captured.

Thanks to EctoLabs and Countspatula I had a great starting point with the programming. I started asking around and eventually found someone who could help me. The original code does this.

Code: Select all

  // Play capture SFX
    if(sfx==true){
      musicPlayer.stopPlaying();
      musicPlayer.setVolume(30, 30);
      musicPlayer.startPlayingFile("cap1984.mp3");
    }

Basically, from what I understand this code basically stops whatever sound is playing, sets the volume and then starts playing the capture sound clip.

What I did was this

Code: Select all

// Audio Track Random
char trackName;

]// Play capture SFX
    if(sfx==true){
      musicPlayer.stopPlaying();
      musicPlayer.setVolume(50, 50);
    char trackName[ 13 ];
    int group = 4;  // can be 1 to 10 for your code
    sprintf( trackName, "trk%02d_%02d.mp3", group, random( 8 ) );
    Serial.println( trackName );
    //  output will have the form "trk09_07.mp3", assuming the random number was 7
      musicPlayer.startPlayingFile( trackName );
    }

What this basically does is, creates an array that builds the track name. It then chooses one at random (between track 00 and 08) and then begins to play it.

The tracks on the SD card are named trk04_00.mp3, trk04_01.mp3 and so on.

Depending on the number it generates it will fill in the "trackName" and play it. So basically what it was doing in the first code snippet, only this one generates a random filename for it to reference.

I ain't 'fraid!

The next step was to come up with some ghost sounds. I'll be adding to this as time goes on, but I wanted to start with a variety.

To do this, I took the original sound and then using a multitrack editor found sounds that I could manipulate to sound like ghosts. Some others were a little more special.

Tracks:

1. Capture Sound 1984 - No ghost
2. Tasmanian devils screaming
3. "Slimer" using BBC Sounds of Death and Horror "Mad Gorilla"
4. Cougar (Mountain Lion)
5. Woman Screaming
6. Boogieman: Real Ghostbusters - Season 1 Episode 6
7. SamHain: Real Ghostbusters - Season 1 Episode 8
8. Spongebob
9. Spongebob Screaming

If you would like to use them, you can get them here.

https://drive.google.com/drive/folders/ ... sp=sharing

I still have some more ideas for ghosts, but this will get me started. I have some other code tweaks to make as well, but for now I finally have a working trap.

[ImperialWalker]

Take off, you hoser!

I started this project with the hose and since the first day it has bothered me. I think it was pretty inventive the way that Countspatula modified the existing hardware to work as a switch. Full credit to that ingenuity.

The original plans call for cutting down a plunger inside the female housing to make room for a small pin inserted into the male end of the Foster connector. In a previous post I explained that I never really liked this for a few reasons.

...

First, it requires the pin and the thin surface of the plunger to come into and remain in contact. In my testing this proved to fail in exactly the way I expected.

As the hose spun, it would knock the plunger out of alignment on both sides. The contacts would be severed and the pedal would stop working.

Second, I don't like the little pin sticking out of the Foster connector. To me, it is ugly and sharp. And while it doesn't stick out that much, I didn't like that it could be knocked potentially bending it or shoving it into the Foster connector.

...

So, I figured why not see if I could spend an afternoon and improve things.

The Parts



My goal was to create a nice, big contact area that would maintain a connection while also allowing the hose to spin without issue. To do this I realized I was going to have to find a way to fill in the gaps on the plunger, while also widening the end of the rod in the Foster connector.

The solution for the rod was simple. Solid Brass Escutcheon Pins.

https://www.leevalley.com/en-ca/shop/ha ... cheon-pins

It is important that these be solid brass. The wall hanger versions in the big box stores are not solid brass (brass coated) and don't contact electricity at all.

The large nail head fit perfectly on the 3D printed Foster insert and helped distribute the pressure better. Being that it was a rounded nail head, it also meant that it could not be pushed into the Foster connecter if knocked. I used a cutoff wheel to remove the pointy bit, then cut a groove.

This allowed me to tin this groove with solder and then lay in a wire. The groove allows the wire to come directly out the back, resulting in a less bulky end (it also allows it to fit into the Foster, protecting it and eliminating the need for bulky heat shrink).

On the other end, I lightly sanded a flat spot for more surface area.

...

A larger brass rod was used for the plunger. I used a micro-saw to carefully cut two cylinders the same depth as the plunger 1/16" I believe.

This would be my flat surface area.


Plunger



The next step was to cut a groove into the brass rod to allow it to fit over the plunger. This was again done with a micro-saw and a file.

I also reduced the top of the plunger by a tiny bit to compensate for the thickness of the top of the rod. If I didn't do this, the brass rod would sit too high as well as making the plunger too tall.



Once it was shaped correctly, I covered the plunger with flux and heated it up from the top. This pulled the flux into all the gaps and around the edges.

I then came in with an hobby blade and some sandpaper to clean up the entire part and make it pretty.

...

Final Assembly

The result is exactly what I am looking for. The large brass surface area along with the pin allows for really nice contact while also allowing the hose to spin. No matter how many times you spin the hose, it will not push the plunger sideways. In fact it no longer can as the plunger is now evenly distributed on all sides.

It is a small upgrade, but one I think will result in a more robust system. Plus, the pin in the Foster looks slick.