#4938920
"Yet another trap build?!" I hear you cry. Well, yes, yes it is. There will be photos, lots of them.

Since there doesn't appear to be any build threads for Ben's kits I thought I'd do one myself. After reading some of the amazing build threads on here (shout out to bromie, damster117, Filandrius, noslliT, barison82, mburkit and a few others) I was inspired to take Ben's kit a step further, and upgrade a lot of parts where possible. It's not modelled on any one trap, more a general homage to the GB1 traps.

Trap Parts list

Trap & cartridge - Benofkent
Aluminium trap side plates, bargraph plate, cartridge front plate, battery box cover, cartridge base, rails, side rods and handle - Click Metal
Trap Vector plate - Charlesworth Dynamics
Raytheon pointer knob and skirt - eBay (I Frankensteined an MS91528-1P2B pointer knob together with the skirt from an MS91528-1F2B round knob)
Heathkit knob - user gbmichael
CAL-R MC250 resistor - eBay (maybe someone on here, seller asked me if they were for GB props rather than "proper" usage)
Cartridge rectangular side vents - Wickes
Cartridge round side vent - eBay
Front knob KN500A - RS Components
Front knob KU4025B - user gbmichael
Front slider knobs - RS Components (not 100% happy with the side of these, but couldn't find anything closer to the dimensions I wanted)
Male Foster 22-2 Connector - Radwell
M3 x 6mm countersunk socket screws - Westfield Fasteners (for side vents, cartridge base and side of trap body)
M3 x 8mm countersunk slotted screws - Westfield Fasteners (for track rails)
1/8" and 1/4" potentiometers - Farnell
Imperial socket cap and button cap screws - Modelfixings.co.uk
Flat toggle switch - Farnell ( think I might replace this with the correct Alcoswitch, as it'll cost about the same as getting a finishing nut anyway)
D-sub male / female - Farnell

On to the build!

There was some of the usual clean up, priming, sanding, priming, sanding of any 3D kit. You know the drill, I won't bore you with that.

Out of the box Ben's trap has a removeable cartridge, happy days. But, I wanted to do a rail system, and add side vents. Adding rails would cause the cartridge to sit too high in the trap body, and look a bit weird. The cartridge is also quite a snug fit in terms of width, so adding vents was a no-go. So I did what any sensible person would do and took a razor saw to the cartridge to reduce the height by about 5mm, and the width by 3mm.

Image

Image

Glued the two halves back together, and whacked on some P38 body filler to fill the gaps where my cut wasn't quite parallel.

Image

After sanding back the filler

Image

The front of the cartridge also sat flush with the edge of the main trap body, with the door mounting lugs being flush to the back end of the cart, which didn't look quite right to me (maybe it's accurate to GB2? I dunno), so I glued some 4mm styrene sheet onto the back of the cart to lengthen it a bit. This will also give me the added bonus of being able to add the welds onto the door lugs. Should also mention I wanted to include a d-sub, so I chopped out some of the back of the 3D print to mount it through.

Image

Before clean up. The top nearside corner got cut slightly wonky, so I had to build that back up with filler later on.

Image

Lots of careful marking up for the d-sub and I chain drilled out the hole for it.

Image

About an hour of careful filing, testing, filing, more filing, even more filing and I had a pretty snug fit for the d-sub! Hurrah.

Image

Quick test fit of the doors. I replaced the M3 bolts in Ben's kit with #6 hex head bolts from modelfixings.co.uk too. As I'd narrowed the trap body there was some sanding of the doors to get them to fit nicely, they had quite a noticeable gap previously, so I need to consult some reference photos and possibly make them a little narrower still.

Image

As I mentioned before, I want vents on the cartridge body, so following damster117's lead I got some soffit strip from Wickes and cut them down to size, filled the unwanted gaps with more body filler, countersunk some holes in the corners and had some nice side vents. I didn't have quite enough space in the trap body to do a double layer like damster did, so they're glued to 0.5mm styrene sheet to make them a bit thicker. Looking at one of the reference photos it does look like the vent cut outs might not be quite the depth of the whole vent anyway, although that might be a trick of the light in the photo? The eagle eyed among you might notice they don't have the right number of vent slots, because I made the cartridge height shorter they came right up to the very edge if they did, so I reduced them by one. +100 geek points if anyone ever calls me out for it! For reference, they're all mounted with M3 countersink screws, and I've got the circular one on the way from eBay as a 33mm diameter / 1.5mm thickness aluminium disc for something like £1.50.

Image

Image

Where possible I wanted to use aluminium too, as painting 3D prints to look like real metal sucks, and the real deal will gradually weather nicely if it's painted. I was a bit nervy about getting a large sheet of 2mm aluminium and being able to cut it accurately/straight enough, so I got all the aluminium parts cut to custom sizes from Click Metal, and despite them stating they have a +/-2mm tolerance the parts I got were pretty much spot on!

Added the front plate, again with #6 screws from modelfixings.co.uk. It's very slightly too narrow, so I may yet replace it if it keeps bugging me. Still need to drill mounting holes for the front knobs too, and planning on mounting them on potentiometers so they turn.

Image

Then added the bargraph plate, with more #6 screws. The bottom two were slightly off where they should be, but I think I can probably live with it for now.

Image

Some drilling and much filing later, I had a pretty perfect fit for one of Spongeface's beautiful bargraph bezels! Still need to drill a hole for the LED to the right of the bargraph, but until I know what size I'll be using I'm going leave that.

Image

Now I'm waiting on a new smaller countersink drill bit to arrive tomorrow so I can drill the aluminium base plate and mount it with countersunk screws. Having a removeable base plate also means when I work out the way forward on electronics I can easily get in to add them in. Then I need to decide on where the front knobs will go, and get the mounting holes for those drilled out too, after which I can think about paint!
#4940044
Plenty of progress to report since my last update!

Smaller countersink bit arrived, so I got the replacement aluminium base of the cart on. I had to add in some bits for four of the screws to go into, as the walls weren't thick enough to screw into, just used some more 4mm styrene cut into squares and glued in so they sat flush with the body of the cart. Drilled and tapped them, and they hold fine!

Some of the countersinks were a bit wonky, I later found that you don't countersink aluminium at the same speed as you drill holes in it, in fact the total opposite! I was drilling the pilot holes at 2500 RPM, but doing the countersinks at more like 250 RPM and got a lot less deformation of the countersink. It's really apparent on the second photo below. This got mostly sorted later on, as I had to countersink the screws a little bit more so they didn't catch on the rails, so that was fortuitous!

Image

Then set about getting the rail on the bottom of the cartridge as well. I followed Bromie's dimensions for the rails, 25mm and 35mm width rails, using 1.5mm thick aluminium. All mounted together with M3 slotted countersink screws, and nuts on the inside of the cartridge just to make sure they don't work loose at all.

Image

I got fed up of everything being in primer at this point, so decided to get some paint on the cartridge at least so I felt like things were a bit more "finished". Behold, the cartridge with paint and most of the screws in! Doors weren't painted at this point, so I didn't bother attaching them. The circular one is 1.5mm thick aluminium from eBay, and after a quick google I found how to draw an equilateral triangle in a circle, so I had the holes nice and evenly spaced.

Image

Still debating whether to lengthen the right hand vent on this side to better match the screen used traps. It's a bit of a pain in the arse, so I'm erring towards not bothering. Sorry detail geeks!

Image

Added the welds on the door mounting posts at some point too, definitely like the look of extending the body a bit so these can be added. I think I'll add on the aluminum bracket on the top at some point soon too. I also got the d-sub mounted in. I think I might apply some epoxy glue on the back of the d-sub, as the screws are barely long enough to get into the mounting holes on it and it might eventually work loose.

Image

Final thing I did on the cartridge at this point was get the front plate mounted. At this point it really came to life! The two round knobs are on 1/4" potentiometers, which are mounted into holes in the cart body itself, I forgot to take any photos of that so you'll just have to imagine it. The sliders are both mounted on 2mm x 18mm spring pins. I think I saw someone else mention them somewhere on here, and I wanted these to move as well so have it a try and they're great. Drilled a 2mm hole through the front plate and into the cart body, then hammered them in (cue lots of nervousness that the joint where I cut the cart in half wasn't going to break!) leaving about 8mm sticking out, enlarged the hole on the back of the sliders to 2mm and then hammered those on and bingo! I have sliders than turn as well. I know the decals on the front aren't GB1 accurate, but I'm still thinking I might add some of Mack's Factory's dry rubs as they look awesome in my opinion. You can just see the bargraph plate peeking over the top too, I attached that at this point as well. You can just see the seam where I joined the two halves in this photo too, but I can live with that. It's less noticeable in person.

Image

At this point I couldn't do much more on the cartridge, so I started concentrating on the trap body itself. That'll be a post for later though, as I need to go cook Thai green curry for dinner!
kahuna900, mike_waclo, RedSpecial and 2 others liked this
#4940383
Onto the main body of the trap now!

I've not modded this nearly as much as the cartridge, so this was a bit "easier" to do. First thing was following a few other's lead I countersunk holes for screws just below the bottom edge of where the side plates sit. They're purely cosmetic, but a nice little detail. There's one above the top corner as well, which shows a little more once the side plates are on.

Image

Ben's kit has these big holes in the back wall of the trap, I guess to run electronics through if it's a static trap? There were some very shallow channels either side too, that had a counterpart on the back of the cartridge, to help align to the two, but they were covered over now, so these weren't needed either. They all needed to go though!

Image

I filled the holes with some more 4mm styrene, and then liberally applied Isopon P38 filler to create a flat back for the male half of the d-sub to mount into. I filled both the round holes too, as I'm mounting the battery box a different way than Ben intended, and the top one was bang where the d-sub needed to be anyway. It was a bit of a bugger to get into the corners to sand it, but it turned out ok in the end.

Image

Next step was to get the other half of the rails in, as I wouldn't know exactly where to mount the d-sub until I'd done this. Following Bromie and damster117's builds pretty closely I settled on a small gap at the front, as that seems to be pretty accurate to the screen used traps. I had the same issue that the screws need to be countersunk pretty deep to make sure they don't catch at all (that's what the arrows in Sharpie are, the holes that needed to be deeper). I had to put a slight countersink in the middle layer of the rails so that the screws would sit deep enough, so bear that in mind if you use 1.5mm (1/16") thick aluminium for a rail system.

In the first photo above you can see that Ben's kit has a void in the floor of the trap (for batteries/electronics), which caused a slight problem as all bar one of my screws went through into that, so had nothing to bite into to hold the rails in place! I've used a piece of scrap wood I had that was almost exactly the right depth to fill the hole, with a piece of 1mm styrene sheet glued on to make it flush with the bottom of the rails. It's a pretty snug fit, so once the rails are screwed in place it won't come out. I've drilled holes in the block so I can access the nuts on the screws for the wheel blocks too, should I ever need to remove those.

Image

Once these were in I did a dry fit of the rails. Took quite a bit of adjustment on the rails to get them to be a smooth fit, but nothing that disassembling them and some gentle work with a file and some fine sandpaper didn't fix. I'm hoping they still work as well after painting!

Image

With some careful measuring I worked out where the male d-sub needed to be mounted, and following the same method as the female part got that attached. The screws don't sit flush, so I subsequently enlarged the holes on the d-sub, which had the annoying impact of separating the two metal halves! Fortunately they glued back together ok with some contact adhesive, and the enlarged holes allowed the screws to sit further in.

Image

They joined up perfectly first try! Hurrah! Big relief, as I had visions of them not lining up and having to use loads of filler to fill the hole, and recut it.

Image

Somewhere during this I mounted the potentiometers for the Raytheon pointer knob, and the Heathkit knob as I wanted both of those to rotate as well. Both are a 1/4" shaft, but the Heathkit is a D shape, so I had to file that shaft down to fit. I worked out where they needed to be set by attaching Ben's 3D printed side plates and marking where the hole for the knobs was, and then used that as the centre point for the hole for the potentiometer. Drilled corner holes, then used a keyhole saw to cut out the square shape, and then filed it to shape until the potentiometer's fitted nicely. Got them sat in place, and then slapped some more P38 filler on the back of them, and made sure they were held in place until that set, then sanded it smooth. From the inside of the trap you wouldn't know I'd cut a bloody great hole (about 23mm square) in the side, and the outside is hidden under the side plates so doesn't matter too much.

Image

Image

Image

At this point I also refilled the holes along the bottom edge as they weren't quite close enough to the edge for my liking, and then re-drilling them. I made the countersinks a bit smaller too, as some of the previous ones were a bit too large.

Next job was the battery box, not much to write home about on this one. I replaced the cover with 2mm aluminium as well, and rounded the top edges of the box off, as well as filing some grooves into the corners to give the impression of it being folded aluminium sheet (saw someone else do this in one of the other build threads - can't recall who but thanks for the idea!). I've used button head screws to attach the lid, rather than the socket cap screws Ben supplied. Got the Linrose indicator from Charlesworth Dynamics, and may yet swap out the toggle switch for the correct Alcoswitch model so I have the right mounting nut. Go big or go home, right? Welds were added with Milliput, and then tapped the hole for the Foster connector so it screwed in nicely.

Image

I've attached the battery box from inside the trap, which whilst not screen accurate allows me to easily remove it if I need to get access to the back of the d-sub or the switch / Linrose light when I sort electronics. I've got two countersunk screws above and below the d-sub, and they will also serve to hole the handle in place when I get that sorted too.

Image

Image

That brings me about up to the photos I've uploaded so far, so more updates will be later this week!

    A minor note but Curt Sobel went to a scoring sess[…]

    While building my pack I’ve thought back to […]

    3D printer Kenner RGB stuff?

    Old topic but I was finally able to attach the s[…]

    I used that same type of wireless switch to fix my[…]