A Beginner's Guide: How To Scratchbuild a Servo Arm

[YorkNecromancer]

A Beginner's Guide: How To Scratchbuild a Servo Arm

Ahoy-hoy, ladies and gentlemen. Apparently I'm back with another one of these.

As you may know, I am in the process of creating a Preheresy Iron Hands army using only GW components and scratchbuilding because I love Heresy-era stuff and FW prices are bonkers. So, this week's Beginner's Guide to Scratchbuilding is going to be of use to Iron hands players, as well as those of you who fancy yourselves Mechanicus Magi and Big Meks. I will be showing you what is literally one of the simplest scratchbuilds you can do: a Servo Arm. It takes under fifteen minutes to get the core piece built (although obviously, greebling will take longer) and once you've made a few, you can start to adapt the design for all sorts of things – everything from bionic limbs to walker legs. I've used it when scratchbuilding some AdMech Castellax, so trust me when I say it's a versatile design.

The Tools You Will Need.

This week it's incredibly simple:

Poly Cement.
A length of square styrene rod, about 3mm x 3mm.
A length of cylindrical styrene rod, about 5mm diameter.
Other thicknesses of styrene rod for greebling and sundry details.
A small piece of thick plasticard.
Your craft knife.
A Space Marine backpack (if you want to make it for a Techmarine). I've used one of the missile launcher ones I had going spare, but honestly – any backpack will do.



http://th09.deviantart.net/fs71/PRE/f/2014/142/7/1/2014_05_22_15_53_51_by_yorknecromancer-d7jaw5t.jpg


How To Scratchbuild a Servo Arm

Cut one of the vents off your Marine backpack.
http://fc04.deviantart.net/fs70/i/2014/142/2/0/2014_05_22_15_54_54_by_yorknecromancer-d7jaw5o.jpg

Cut three lengths of the square rod. They should be about 8mm or so long if they're going on a Marine.
http://fc03.deviantart.net/fs70/i/2014/142/9/9/2014_05_22_15_55_42_by_yorknecromancer-d7jaw5j.jpg

Using the 'roll – score – crack' technique we learned during my Heavy Bolter tutorial, cut three lenths of cylindrical rod. They should be only slightly thicker than the width of the square rod.
http://fc02.deviantart.net/fs71/i/2014/142/b/1/2014_05_22_15_56_44_by_yorknecromancer-d7jaw5f.jpg
http://th04.deviantart.net/fs70/PRE/i/2014/142/1/0/2014_05_22_15_57_05_by_yorknecromancer-d7jaw5c.jpg

Arrange your pieces – I'm sure you can see how this is going to work already.
http://fc06.deviantart.net/fs70/i/2014/142/c/7/2014_05_22_15_57_52_by_yorknecromancer-d7jaw56.jpg

Next, carefully shave down on your cyclindrical pieces like so. USE BOTH HANDS! As always, the photo is to show you the position your blade should be in. I cut using both hands. Remember to always be cautious with what you cut away here – it's better to cut a little and take away more than to cut away too much and have to start again. Less wasteful too.

http://th06.deviantart.net/fs70/PRE/i/2014/142/2/1/2014_05_22_15_58_56_by_yorknecromancer-d7jaw50.jpg

Here's the kind of flat surface you want. You may have to use the 'blade sanding' technique we learned in the Heavy Bolter tutorial to get it flat and level.
http://th03.deviantart.net/fs70/PRE/i/2014/142/8/c/2014_05_22_15_59_36_by_yorknecromancer-d7jaw4v.jpg

Next, glue it in place:
http://th07.deviantart.net/fs71/PRE/i/2014/142/9/c/2014_05_22_16_01_18_by_yorknecromancer-d7jaw4r.jpg

As always - more when I get a reply!

[Wolfshade]

Moar!

[Thaldin]

I was beaten to the punch! =)

[YorkNecromancer]

Gentlemen: my thanks to you both.

And attach the first 'arm' section.
http://th01.deviantart.net/fs71/PRE/i/2014/142/9/e/2014_05_22_16_02_36_by_yorknecromancer-d7jaw4j.jpg

Carefully shave down the other cylindrical sections, taking care to do two for each rather than one, and assemble your arm! Remember – where you place the flat sections will affect the final position of the arm. I find it best to keep the flat sections between 90 and 120 degrees or so, but you might have your own ideas. If so, go with what you like. Obviously
http://th03.deviantart.net/fs70/PRE/i/2014/142/b/4/2014_05_22_16_05_06_by_yorknecromancer-d7jaw4b.jpg

Next, a little greebling – it's not necessary, but I like to use this technique, as it maintains the illusion that the 'joints' are still cylindrical. Cut a few 'cucumber slices' off a slightly narrower piece of styrene rod
http://fc01.deviantart.net/fs70/i/2014/142/f/7/2014_05_22_16_07_10_by_yorknecromancer-d7jaw44.jpg

Then, using your scalpel, apply them to either side of the joints as a kind of cap.
http://fc07.deviantart.net/fs70/i/2014/142/9/2/2014_05_22_16_07_40_by_yorknecromancer-d7jaw3u.jpg

Here's the finished piece so far – as you can see, the little detailing just adds a little more suggestion of robotics.
http://th09.deviantart.net/fs71/PRE/i/2014/142/a/0/2014_05_22_16_08_31_by_yorknecromancer-d7jaw3m.jpg

Now, you may want to add a piston here – you don't have to, but they look pretty good.

To do so, you'll need two different thicknesses of cylindrical rod – each thinner than the 'joint' rod. Cut off two short sections like so:
http://fc07.deviantart.net/fs70/i/2014/142/f/b/2014_05_22_16_10_02_by_yorknecromancer-d7jaz84.jpg

Next, add a dot of glue to the underside of the middle 'arm' piece, like so:
http://th08.deviantart.net/fs70/PRE/f/2014/142/8/5/2014_05_22_16_10_43_by_yorknecromancer-d7jaz7z.jpg

Place the tip of the thin rod into the glue – don't worry about getting it perfect.
http://th01.deviantart.net/fs71/PRE/i/2014/142/5/6/2014_05_22_16_11_15_by_yorknecromancer-d7jaz7v.jpg

More when there are replies!

[Digitarii]

More details, dammit! We must be shown the PPPrecioussss servo arms!

[YorkNecromancer]

I am happy to provide.

Glue the thicker piece as shown, and use the tip of you scalpel to move the pieces around until they are straight, level, and looking like a piston.
http://fc02.deviantart.net/fs71/f/2014/142/9/1/2014_05_22_16_12_22_by_yorknecromancer-d7jaz7q.jpg


Now to make the claw. You can basically add anything to the end of these arms, but the claw is the classic look, so that's what we're going to do now.

Start by measuring your small piece of thick plasticard – you're going to want to get a rectangular piece about 3mm high x 10mm long:
http://fc04.deviantart.net/fs71/i/2014/142/1/a/2014_05_22_16_13_40_by_yorknecromancer-d7jaw3f.jpg
http://fc00.deviantart.net/fs71/i/2014/142/1/f/2014_05_22_16_15_57_by_yorknecromancer-d7jaw36.jpg
http://fc00.deviantart.net/fs71/i/2014/142/e/5/2014_05_22_16_16_26_by_yorknecromancer-d7jaw33.jpg

Next, measure 3mm or so from opposing ends, like so:
http://fc07.deviantart.net/fs70/f/2014/142/8/f/2014_05_22_16_17_04_by_yorknecromancer-d7jaw30.jpg

The aim is to create a diagonal!

Once you've measured, place your blade so that it touches both marks, and cut.
http://fc04.deviantart.net/fs70/i/2014/142/7/0/2014_05_22_16_17_37_by_yorknecromancer-d7jaw2x.jpg
http://th02.deviantart.net/fs71/PRE/f/2014/142/8/3/2014_05_22_16_18_00_by_yorknecromancer-d7jaw2u.jpg

You may find that one 'claw' is a little longer than the other – just trim them down so they match.
http://fc01.deviantart.net/fs70/f/2014/142/2/5/2014_05_22_16_19_17_by_yorknecromancer-d7jaw2r.jpg
http://fc03.deviantart.net/fs70/i/2014/142/3/7/2014_05_22_16_19_41_by_yorknecromancer-d7jaw2q.jpg

Place them against the square rod, and roughly work out how much you need to get the look you like. Once you've worked it out, cut the rod, and glue on the claws.

Here's me working out where to cut…
http://fc05.deviantart.net/fs71/i/2014/142/2/3/2014_05_22_16_20_15_by_yorknecromancer-d7jaw2n.jpg

(Only one bit left!)

[Houghten]

I look forward to seeing how you squeeze all the detailing into only one more step.

[YorkNecromancer]

How to detail was covered in my previous tutorials, so I left it out here - it seemed redundant. This will teach you the basic structure. I'm planning a separate tutorial on Advanced Greebling for some time in the future. At the moment I'm trying only to include very basic new information - it's for beginners. However, if you'd you'd like the details from earlier guides, the links are here: http://www.lounge.belloflostsouls.net/showthread.php?44720-Scratchbuilding-a-Heavy-Bolter-with-Plasticard-A-Beginner-s-Guide and here http://www.lounge.belloflostsouls.net/showthread.php?44988-A-Beginner-s-Guide-Scratchbuilding-an-Assault-Cannon-with-Plasticard.

… and here's the finished claw.
http://fc01.deviantart.net/fs70/i/2014/142/7/3/2014_05_22_16_22_32_by_yorknecromancer-d7jaw2i.jpg

Then all you need to do it glue it, and – bar any greebling you might wish to add – you're done!
http://fc00.deviantart.net/fs71/i/2014/142/d/e/2014_05_22_16_23_41_by_yorknecromancer-d7jaw2b.jpg

Now, the above example is simple and ungreebled – but you can go crazy with this:

http://th07.deviantart.net/fs71/PRE/i/2014/142/1/a/2013_08_08_01_54_30_by_yorknecromancer-d7jaw60.jpg
http://th05.deviantart.net/fs70/PRE/i/2014/142/4/8/2013_08_08_01_55_23_by_yorknecromancer-d7jaw5w.jpg
http://th06.deviantart.net/fs70/PRE/i/2014/142/d/b/big_mek_buzzgob_by_yorknecromancer-d7jb12k.jpg

So, that's the end of another Beginner's Guide. Thank you for taking the time to read, and if these articles have inspired you to give scratchbuilding a go, please post what you've created – I'd be fascinated to know if they've actually got anyone involved in what is easily the most creative and exciting, yet most unsung part of the hobby!

[Levaticus]

Gods above! I've been trying to figure out how to make a servo arm for a kitbashed techmarine. Thank you so much!

[Wineshark]

GREAT tutorial. Thanks for taking the time!

[Rob Spring]

Agreed thanks. Will be using some of those techniques soon

[YorkNecromancer]

To the chap on Facebook who said


Hmmm instead of cutting the round joins to create a flat surface i would file the square piece to fit flush onto the round piece. Would look cleaner just a thought

I do agree - that definitely looks better. However, my aim here is to try and create a series of very easy scratchbuilds which enable the absolute beginner to produce something that looks good, and in doing so, enables them to develop the more advanced skills. I think cutting a flat edge through cylinder is a little easier than cutting a curve out of a straight arm, and so that's why I made the decision I did: it's all in the name of ease for the newbie.

Hope that clarifies. :)

[Fraser Kelly]

As a newbie to modelling I love your tutorials! I will post some of my conversions for advice/opinions soon (maulerfiend made from a helldrake, forgefriend from a dreadknight etc), but articles like this greatly help me learn valuable techniques I can use in future projects- keep up the sterling work please and the simpler the better :D

Morgoff

[YorkNecromancer]

You're really very welcome.

One thing I will say is that the thing I like about this scratchbuild is how easily it can be repurposed into other designs. For example, here's one of my Techmarines with a Conversion Beam Projector. I've adapted the design above into a Smart Gun rig (because look at the size of the damn thing. Even in power armour, he's going to need help!)

For those youngsters unfamiliar with Smart Guns, they're from the seminal 1986 sci-fi film 'Aliens', and are essentially a greebled MG 42 mounted on a steadicam rig (the idea being that the rig allows the firer to operate the heavy weapon with increased accuracy and automatic aim). They look like this:

http://img2.wikia.nocookie.net/__cb20130407082211/avp/images/e/e5/Drake_Smartgun.jpg

And my techmarine looks like this (painting isn't finished yet BTW):
http://fc02.deviantart.net/fs70/i/2014/143/4/7/20140523_21_53_17_by_yorknecromancer-d7jgbov.jpg
http://fc07.deviantart.net/fs70/i/2014/143/f/f/20140523_21_53_28_by_yorknecromancer-d7jgboe.jpg

So I think the servo arm is a really solid little scratchbuild that every hobbyist should have under their belt. They're so easy and versatile.

Also, if you haven't watched 'Aliens' and you're old enough to, you really should watch it as soon as possible.

I'm not kidding: as soon as possible. You WILL thank me.

[Kaptain Badrukk]

Just seen this thread, York mate THAT'S AWESOME.

[YorkNecromancer]

Thank you, you're very kind. :)

It's almost exactly the same as the servo arm in the tutorial, only each of the visible sides has a piston on the side, to suggest mechanical power. The key to any successful conversion is effective greebling. If you want one, I hope you decide to make one - it really is easy! :)

[Jose A. Fabian]

You're really very welcome.

One thing I will say is that the thing I like about this scratchbuild is how easily it can be repurposed into other designs. For example, here's one of my Techmarines with a Conversion Beam Projector. I've adapted the design above into a Smart Gun rig (because look at the size of the damn thing. Even in power armour, he's going to need help!)

For those youngsters unfamiliar with Smart Guns, they're from the seminal 1986 sci-fi film 'Aliens', and are essentially a greebled MG 42 mounted on a steadicam rig (the idea being that the rig allows the firer to operate the heavy weapon with increased accuracy and automatic aim). They look like this:

http://img2.wikia.nocookie.net/__cb20130407082211/avp/images/e/e5/Drake_Smartgun.jpg

And my techmarine looks like this (painting isn't finished yet BTW):
http://fc02.deviantart.net/fs70/i/2014/143/4/7/20140523_21_53_17_by_yorknecromancer-d7jgbov.jpg
http://fc07.deviantart.net/fs70/i/2014/143/f/f/20140523_21_53_28_by_yorknecromancer-d7jgboe.jpg

So I think the servo arm is a really solid little scratchbuild that every hobbyist should have under their belt. They're so easy and versatile.

Also, if you haven't watched 'Aliens' and you're old enough to, you really should watch it as soon as possible.

I'm not kidding: as soon as possible. You WILL thank me.

That's actually how I want to do my hurricane bolter sponsons for the stormraven- have the door be open and act as a platform for a marine holding a gatling gun, and have the gun being attached to the inside of the 'raven through a servo arm.

[daboarder]

nice mate, very nice good to see others doing how to's.