Constructing bolter barrels with styrene: advice needed.

[p34ce]

Gentlemen, I am in need of some expertise.

 

I've recently acquired some nice FW resin pieces for making a character, one of which is Carab Culln's storm bolter. I am absolutely smitten with how clean and large the barrels are, and I would like to achieve a similar effect on the other terminator storm bolters in my force.

 

I've also seen a similar conversion where the modeller used barrels cut from ordinary bolters to good effect. I've done the arithmetic, though, and it seems it would be surprisingly expensive per weapon (cost of bits, etc) to do it this way.

 

My current thought process is to use styrene rods or tubes. I've sourced some different sized rods/tubes, and I'm in the process of finding out what sizes I need. My plan is to drill a few millimetres down into the body of the storm bolter, mount the styrene in the holes, and then drill out the vent holes on the sides (and the main barrel hole if necessary).

 

Does anyone here have any experience with this sort of conversion? Perhaps to repair bolters damaged during drilling? Unfortunately, I don't have a Vernier calliper handy to actually measure the piece I want to emulate, so if someone knows what a good outer/inner diameter is for bolter barrels I'd be hugely appreciative.

 

Thanks for reading.

[Grotsmasha]

• Another simple alternative is to roll a tube of GS to your desired thickness, then cut it to size. It's how I repair barrels I've messed up'd

Cheers,

Jono

[p34ce]

Yeh, I'd thought about that too, and tried it. I wasn't happy with the results after a few tries. I really loathe working with GS, I only use it for resin repairs and fitting. The reasoning behind styrene is that it's solid, easy to drill, and can be mounted securely in a hole.

[Subtle Discord]

Rod or fine tube is all you need, around the 2.5mm range for a Bolter barrel. You're describing exactly what I would do; drill a hole a place a longer length of rod/tube. You could also use metal tube, which will be thinner and create a more authentic barrel muzzle. It will take a little more care, needing some super glue to assemble, but it's an option.

When it comes to styrene, if you can think of a way to assemble it, it's possible. You just need to be able to make the bits you'll require.

[Firepower]

2.5mm sound awfully thick for a bolter barrel.  Just looking at it on my ruler, it's thicker than a bolter by a wide margin.

[Subtle Discord]

I used a digital caliper to measure the barrel on my Chaos Marine, 2.35mm. You won't find 2.25mm, and I figured 2.5 would be closer. On looking at the actual styrene rod, you're right, 2mm is closer to what you'll want.

[Firepower]

Are we talking Storm Bolters or regular Bolters? 

[p34ce]

Storm bolters. Thanks for actually measuring it for me, lol.

 

The smallest tube I can see is 2.4mm OD/1.5mm ID. I just did a rough measure with Culln's storm bolter and it looks like about 2-2.1mm. Looks like I might have to use rod instead. Which means lots of annoying drilling. :(

[p34ce]

The horror. The horror.

Everywhere else I look it's all in inches.

[Rik Lightstar]

How many bolters would you hypothetically need?

 

Rik

[p34ce]

If I were using barrels cut from bolters, two for each storm bolter, so 20. Add in enough for the odd screw-up so probably 25.

 

My first though was to order some, but I've yet to see the magic combination of cost and quantity on any one seller. If I got them from different sellers, the postage charges get stupid. It works out to around £0.80 per weapon that way, whereas I can get more rod/tube than I need for less than £0.20 per weapon, plenty of spare material to account for practice, and the end result is likely to be better.

[KhorneHunter57x]

If you wanted to use barrels from bolters, see if any of your local gamers play Black Templars - they're likely to have a number of spare bolters that they probably wouldn't mind parting with.

The horror. The horror.

Everywhere else I look it's all in inches.

FYI, 3/32 of an inch (0.09375 in) is roughly 2.38mm.

[p34ce]

I've checked now, and it looks like 2mm rod is noticably too small. Rod seems to skip 2.38mm and go straight to 2.5mm, which is far too big. I'm going to go ahead and order some 2.4mm OD tube and see how it goes. On the upside, it means the inner hole should be perfectly straight and centred, so the accuracy of the fit only depends on how accurate I am with the mounting holes.

 

I'll post updates at some point and tell you how it goes.

[p34ce]

Alright, my 2.4mm (3/32in) styrene tube arrived today, and I just cobbled together a small (very rough) example of what it's like, for reference:

 

http://i.imgur.com/kmOt9nT.png

 

First thoughts are: the inner diameter needs to be enlarged a little. Obviously, this isn't inset into the pistol (just glued very roughly), because drilling an appropriate sized hole might destroy it if it's off by a tiny amount. I'm hemming and hawing about using wire to mount the barrels instead of an inset. I will be trying a storm bolter soon.

[Subtle Discord]

I'll share my process for drilling really accurate holes, if you like. Every rivet I place in a build (thousands and thousands, by now) is placed in a pre-drilled hole to improve accuracy.

Start with a fine needle or pin and very carefully prick a dot exactly centered; if you have a good eye (and it comes with some practice) you'll be able to obviously see if it's good or not. Be honest with yourself if it's off, and use a hard tool to rub the hole down and make an adjusted hole. use the first hole as a guide.

Once it's right where you want it, get a larger push pin (the ones with a plastic or metal nub/handle) and use that to make that first hole much larger and rather deep. Again, look at it, and be honest if it looks off. At this point you might have to stick with it (you can only drill so many of the pin holes before it gets hard to be accurate) and if you do, take note of the adjustment you might need to make while drilling.

Use the nice large hole as a guide. Now, if you have a few different sizes of drill bits it's usually best to start smaller and then work up if you are unsure; this gives you some room to correct mistakes. Start with a 0.75mm and 'back-drill' in the hole. Do not drill forward to actually drill a hole, drill backward with some pressure to force a nice 'V'-shaped seat for the drill bit to sit in. Now is the time you can push a bit in a direction, to nudge the hole a bit if it needs a bit of adjustment, but you can only do so much. Take the drill bit away and have a look; is the 'V' still centered? If no, try to back drill a bit more and nudge it a bit.

If yes, place the bit back in the 'V' and drill forward a little to start the hole, but don't go too far. After a few turns take one last look to make sure it's going where you want, and then commit to the hole. Once you have a very centered guide hole, you can enlarge it by placing the bigger bit on the hole, back drill and make sure it's centered, and drill forward letting the smaller guide hole keep things straight.

Note: If you don't have a range of bits, give it a try with the exact size you need, but with the same methodology; it does take a bit of practice, but once you get the hang of it you can do it freehand with just one good pin-prick.

Edit Note: If you find your drill bits are not up to the task and are tearing and twisting the plastic, you might be pushing too hard, and/or the bits might be low quality and/or dull. I swear by purchasing my drill bits (and files, and razor saw blades) from jewelery supply sites like Contenti. You pay a very reasonable premium for tools that will be top quality. These bits cut like a knife through butter; and don't get me started on the wonderful files.

[p34ce]

Yep, that's near enough what I do when doing magnets - except they don't have to be as accurate. It turns out, though, that I don't actually have a 2.4mm bit to hand, so I had to order one. I have something like 15 sub-5mm twist bits and not a single damned one the right size.

 

What I don't have is a proper centre punch. I've been using an old, damaged airbrush needle for a year lol.

[Subtle Discord]

The needle and pin you use don't need to be elaborate or purpose built. Find a good quality sewing needle and/or push pin (ones with small metal discs for a head), and a few proper push pins you use on bulletin boards. You might need to take a piece of plastic or sprew, drill a hole in it and glue the pin/needle into the hole to give it a handle, but it's a simple task. I use needle pricks to transfer my build templates down to plastic, and every prick has been done with a home made sewing needle tool. Nothing wrong with improvising and making your own simple tools.