Tech Tip-020
Making Metal & Music Wire Gizmos:
Rings, Pins, Hinges, Latches, Springs & More.
Dedicated to the dissemination of detailed model building methods and techniques.
Materials and methods presented here are not intended as the best or only solutions to the modeling challenge(s)
discussed, rather as methods and procedures which have a proven record of success in actual use. Please keep
experimenting with new materials and techniques as this is the only way to expand the fields of knowledge.
Written by: John E. McCoy Sr. NAR-15731 - Club presentation: 06-01-2013 – Rev.-04-16-2016
We often run into situations within the hobby where “Standard” material or parts generally used or
needed just do not fit the model or application. On occasion we will need to create a small metal wire, strip or
tube that will do the job without violating our Safety Code consideration regarding “no major metal parts”. All
items discussed in this Tech-Tip fall well within this parameter.
Some of the various doodads, gizmos and gadgets we’ll be looking at will cover items such as: Home
made motor clips. Springs of various sizes and shapes used for Flex-wing, Pop-out fins, BG & RG actuators,
Scale model antenna launch lugs, pins, plates and other tiny details, Helicopter and Swing Wing Hinges, Pins
and rings.
Our basic material for the vast majority of these Micro, Model and High Power size rocket parts will be
Hardened Steel Music Wire or a bit better 304 Stainless Steel Music Wire. Occasionally circular & rectangular
brass and aluminum tubing, thin sheet brass, aluminum or stainless items may be needed to complete either the
model or support equipment.
*Because actually making these often tiny parts really must be seen to be appreciated or leaned some
photos will be added showing the process but it is highly recommended attendance and observation at the
June 2013 meeting will help take most of the fight out of learning the fabrication process.*
To begin let’s look at the different base materials, sizes and why they could be useful in our particular
construction:
Over time I’ve learned that some of the most common 1080 Carbon Steel hardened music wire not only
can but will rust to the point of failure. While this series wire can be had in finer gauge pre-straightened 12”
lengths down to .009” diameter at very inexpensive prices the rust factor is something to be considered in our
purchase practice. Common carbon steel music wire can be obtained from your local hobby shop, hardware
store and some home improvement stores. Most of these locations will have precut lengths in 1 to 3 foot
lengths bundled in single to 5 or 6 piece packs depending on diameter or wire gauge. However we can get a
better purchase from an industrial supply such as McMaster-Carr with known USA supply sources.
McMaster-Carr offers 1080 carbon steel pre-cut 1 foot length, 100 piece packs. Over time these gauges have
proven to be most helpful and are suggested: #8907K92 - .010” diameter @ 9.24/pk., #8907K97 - .016”
diameter @ 8.40/pk., #8907K98 - .018”diameter @ 8.40/pk. and #8907K21 .020” diameter @ 3.53/pk. While
Hardened Steel has a tendency to rust, which may or may not be an issue making our parts, the rust potential
can be eliminated with the purchase of 304 Stainless Steel spring temper wire as an option for most diameters.
Stainless is a bit more expensive and is only available in precut lengths down to .020” diameter. It is my strong
suggestion .020” and .022” diameter Stainless wire become the standard on every workbench.
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For thinner pins, antenna, launch lugs & hinges 1/4lb rolls of 304 alloy stainless wire are available from
McMaster-Carr in the following suggested gauges #9495K52 .010” diameter (930’) @ 15.04/roll and
#9495K59 .016”diameter (360’) @ 11.59/roll. Generally anything lighter then .010” will be to flimsy for flight
use.
Most springs, flex-wing activator springs and hinge bodies work well with #8908K21 .020”diameter pre-cut
1’-0” length 100 packs @ 12.81 (preferred). For larger birds up to 3.3lb heavier #8908K22 .022” diameter
100/pk @ 12.12/pk or #8908K26 .026” diameter 100/pk @ 12.57 should be considered. The thickest music
wire gizmo I’ve personally fashioned to date was a .091” (3/32”) diameter hardened music wire Dead Bolt Lock
replacement Spring saving me a Sunday trip to the Hardware store. Heavier yet, the same hand tools were used
to Roll 3/16”diameter 304 Stainless rod into heavy Tree Recovery hooks & rings. While none of these were
flying parts I mention them only to show we can make just about any thickness bent rod gadget needed with
simple hand tools, imagination and a little elbow grease.
Making our own Motor Retainer Hooks can be done with #9075K104 .028t x 1/8” Tough wear resistant
#1095 Spring Steel strip on 25ft rolls which can get expensive for making one or two. Here’s a money saving
option for such hooks: The .030”t x 3/32”w Stainless Steel strips from old windshield wiper blades is pretty
easy to obtain and free when we change or wipers. These Stainless strips make EXCELLENT 1/4A thru E
motor hooks.
Other materials to be considered for small parts are alloy 260 Brass rod, sheet, strip and tubing and
3003-H14 Aluminum sheet and strips or 6063-T52 rod & tubing. Some of these materials can be had as thin as
.003” foil or as thick as .063” still bendable with common hand tools. Don’t forget many of the Plastics such
as: Styrene, ABS, PETG, Polypropylene and Polycarbonates which can be cold formed using basic pliers, and
hand tools.
Tools of the Trade:
While we do NOT need a Toolbox full of expensive bending tools, below I intend to list a bunch of very
helpful manual hand tools that will greatly expand the ease and enjoyment of making your own metal, plastic
and some wood or Plywood parts. We’ll start with the very basic tools for “Coffee Table Fabrication” and end
with a few table top tools that will extend the variety of materials and thickness base that can be worked. Many
of these pictured below will be available for your hands-on examination at our June 1, club demo. Feel free to
give any or all of them a try.
Basic wire & metal strip bending tools required:
To be perfectly frank most of the smaller Antenna Lugs, wire loops, springs and hinge bodies need only
a pair of decent needle-nose pliers or Draw Tong -Blacksmith Pliers, Hard Wire Cutters and your fingers.
Please note most side
or diagonal cutter pliers will not hold up or last very long when used to cut hardened steel or stainless steel (2
music wires. It is strongly suggested making the investment in a good pair of hardened wire nippers, Cutters or
mini bolt cutters.
Let us take a look at what we can currently buy from good old Harbor Freight (Not known for the
highest quality tools) but for what we are doing I’ve found some real bargains that have held up well to my
rough use.
* #SKU-31675 Pittsburgh-Harbor Freight 6pc precision pliers set: (Excellent needle nose, bent nose, OK end
nippers, Decent Long needle nose, standard diagonal side cutter, and very helpful Flat Jaw pliers).
Everyday price $12.99, on sale only $6.99
* #SKU-41146 Pittsburgh-Harbor Freight: 8” Bolt Cutter (hardened wire & 1/8” bolt cap.)
Cap. Up to 1/8” Stainless Launch Rods. Everyday $ 3.99
Where sharper corners or tighter radii are not practical with just our fingers a Hammer helps:
* #99895 Harbor Freight: Watchmakers Hammer with 6 heads.
(1/2oz to 3/4oz Heads.) Everyday $ 3.99
* Or #83434 Micro-Mark Brass/Nylon Mallet:
4oz Head ½” Diameter Brass & Nylon Inserts @ 15.75
* Or Micro-Mark #22119 2oz. Head Ball peen Hammer
Std. ¾” Face @ $9.95
From the above we can see it really shouldn’t take much in the way of tools to get started.
Once a little experience is gained some other goodies will likely be added to the wish list and accumulated over
time to help fabrication and/or duplication of parts move a little faster.
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The following listing is by no means complete as we will find different add-ons to this list that will increase the quality
and repeatability of our wire & strip bending. Photos below in sequence left to right.
* 5WR, 7R & 10R: 5”, 7”, & 10” Vise-Grip Locking Pliers: (Various sources)
8.25 to 23.40
* 8R Vise-grip 8”duckbill locking pliers (McMaster-Carr #2445A11)
16.16
* Large & Small wire loop Pliers set (Micro-Mark #50295)
21.15
* 4pc Metal Forming Pliers Set (Micro-Mark #60398)
47.95
* 8pc Coil winding Mandrel Set (Micro-Mark #84118) Almost a must for making good coil springs
19.95
* 5pc Spring type Tube bender Set (Micro-Mark #60360) 1/16”, 3/32”, 1/8”, 5/32” & 3/16” tubes
6.95
* 6pc Spring type Tube bender Set (McMaster-Carr #2420A14) ¼”, 5/16”, 3/8”, 7/16”, 1/2” & 5/8”
11.48
Helpful though expensive Bending Machines & Jigs: Picture below in order L to R.
* Miniature Wire Bender; (McMaster-Carr #2379A11) 1” x 4-3/4” Alum with 4- ¼” pins
8.88
* Vise Mounted Wire Bender; (Micro-Mark #60346) up to 1/8” hard wire
15.95
* Mini 3” Press Bending Brake; (Micro-Mark #16101) Max Cap .020” brass, .063” Alum.
35.95
* Universal wire & strip Bender; (Micro-Mark #82819) wire to 5/16”dia., 1” wide strips to 3/16”
106.50
* Bending Machine Roller/Bender; (Micro-Mark #81356) 3” wide rollers& (1/16” to 1/8” Hard-Wire) 109.95
* Mini 8” Metal Shear/Brake; (Harbor Freight #90757 or Micro-Mark #84734)
HF@199.99 MM@209.95
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Helpful Bending Tips:
* When considering making music wire parts think about the practical size of the object to be formed
and will the music wire part be worth the additional mass including attachment method for your project.
* Does the part being fabricated have to be all metal or would it be better made in whole or part with
ABS, PTFE, PETG, Styrene or another plastic. This is particularly useful while making different size and
weight hinges.
* What is PTFE? PTFE is a vacuum formable very thin but tough clear plastic. Most will recognize it s
the material nearly all “Blister Pac” clear packaging is made of. Blister Pack BP Mod-Roc motors
immediately come to mind. This stuff is generally .010” thick or thinner (after vacuum molding), Crystal Clear
and very tough to tear or break. Cut with Scissors or #11 X-Acto knife blade, this very thin plastic helps make
the folded strip, stationary side of helicopter hinges almost a snap with very good long term longevity. I’ve
actually used this material as a 1 piece hinge simply cold folding in the middle. It’s so tough repeated folding
back and forth will not break this material at the fold joint for many flights.
* Old pieces of 1/8”, 3/16” & ¼” launch rod makes excellent Antenna Lug & Launch Lug forming
mandrels. Clamp a section of music wire perpendicular to the Rod with 5WR or larger Vise-Grip Pliers. Bend
the rod around the mandrel to form a complete loop bending the leg a bit over 90°. With Needle Nose Pliers
grip the wire at the coil junction and fold 90° on both legs. Remove and snip the excess wire leaving extensions
for one of several mounting methods we will discuss.
* Making permanent wire forming fixtures can be done with scrap pieces of wood as the base with
common or finishing nails as the pins. Be sure to remove the nail heads leaving only the filed off or ground
shafts around which to bend and roll the wire.
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