Full Boost Bundle Sizer

Bundle cores i Add your wires Pick a spec (55M or 55A), a gauge, and how many of that wire are in the bundle. 55M covers 24-30 AWG; 55A covers 8-30. Below 22 AWG, only 55A is available.

Packed bundle

i How this is drawn Each circle is a wire at its finished OD (conductor + insulation) from the TE control drawing. Wires are packed tight and an enclosing circle is drawn around them. Enclosure draws an outline instead of the circle and reports the total CSA - the whole area inside it, wires and gaps together, the cross-section an enclosure has to clear - with its width and height. Free-form is the convex outline round the wires; Fixed profile packs them into a set size and shape. Sleeving does not apply in that mode. Wire CSA is the summed cross-section of the wires at finished OD, whatever the arrangement - the figure conduit and raceway fill rules use. Bundle CSA is the enclosing circle's area; total CSA is the area inside the enclosure outline. Fill is wire CSA over whichever envelope is shown. Slide-on is how much wider the sleeve is than the bundle before shrinking (ratio of expanded sleeve to bare bundle OD). Sleeve sizes are from the manufacturer's datasheet: inside diameters as given, wall thicknesses nominal. If a fit is marginal, check the manufacturer's datasheet. Custom adds the wall thickness you enter straight onto the bundle. Enter its expanded and recovered inside diameters too and it gets the same slide-on, grip and recovery figures as a listed size, with the expanded view. Bundle / expanded is what percentage of the expanded sleeve the bundle fills. The tool uses 80% as a default maximum, to leave room to slide the sleeving over the bundle.

Bare bundle Ø

wires

wire CSAmm²

bundle CSAmm²

fill

expanded mm recovered mm wall mm

Width mm Height mm i Enclosure type Free-form - the smallest outline round the wires as they sit. Drag wires and the outline follows. Fixed profile - a profile of set size that the wires are packed into: Height only - the narrowest width that holds every wire at that height. Width only - the lowest height that holds every wire at that width. Both - packs as much as it can into exactly that box and says whether everything fits. Radius - rounds every corner of the profile on the inside to that radius. It is capped at the largest the shape allows: each corner's curve must fit in half of each edge touching it. Margin (tick to apply) - keeps that share of the profile's area clear, shown as the shaded band inside the outline. The wires must fit inside the band's inner edge, which encloses that much less area than the profile, so the profile has room to spare when the wires are placed for real. Custom shape (mouse) - drag a corner to move it, or the dot in the middle of an edge to bend the edge there; double-click a corner to remove it. The wires re-pack into the new shape when you let go. Reset shape goes back to the rectangle. Hard boundary (tick, under the drawing) - while ticked, a dragged wire and the wires it pushes aside stay inside the profile; the drag stops when there is no room left to give way. Unticked, wires drag freely, even out of the profile. Undo (under the drawing, or Ctrl+Z) - steps back through the last five moves: wire, group and bundle drags, Settle, and shape edits. Reset and any change to the wires start afresh. Wires remain in position when switching between the two: press Settle to pull them into the profile, or Reset to re-pack. The packing is the tightest arrangement found. Radius mm Margin %

Add a wire spec above to pack the bundle.

fullboostconsulting.com

▸ Reference & method notes

Geometry only. Each wire is drawn at its finished outer diameter (conductor plus insulation) taken from TE Connectivity control drawings. 55A (55A0111 / M22759/32, tin-coated copper, ETFE, 150°C) and 55M (55M0414, silver-plated alloy, ETFE, 200°C). Wires are packed by a deterministic nearest-fit routine and the bundle diameter is the smallest circle that encloses every wire. Real looms settle differently under tension and tape, so treat this as a tidy-pack estimate, not a guaranteed dimension.

Sleeving uses TE DR-25, DR-25-TW (thin wall) or RW-200-E (high temperature), all 2:1 heat-shrink. A size is recommended that slides over the bare bundle and recovers tight onto it. Sleeved Ø is the bundle plus the size's nominal recovered wall. A custom sleeve takes a wall thickness, and optionally its expanded and recovered inside diameters, after which the same slide-on and recovery figures apply.

Slide-on is how much wider the sleeve is than the bundle before shrinking (ratio of expanded sleeve to bare bundle OD); more makes it easier to fit. It is also quoted as a radial clearance in mm per side.

Bundle / expanded is what percentage of the expanded sleeve the bundle fills. The tool caps this at 80% by default, to leave room to slide the sleeving over the bundle.

Enclosure mode draws an outline round the packed wires - in Free-form, the convex outline: the arcs of the outer wires joined by straight tangents; in Fixed profile, a box or custom shape of set size, optionally with rounded corners, that the wires are packed into - and reports the whole area inside it as the total CSA: wires and gaps together, the cross-section an aperture or enclosure has to clear for the bundle to pass, with its width and height. It is a geometric hull of the wires at nominal OD, before any tape or lashing. Sleeving does not apply in this mode.

Wire CSA is the sum of the wires' cross-sections at finished OD - the same whatever the arrangement, and the figure conduit and raceway fill rules take as their numerator. Bundle CSA is the enclosing circle's area (the headline Ø restated as an area); in Enclosure mode that cell becomes the total CSA inside the outline. Fill is wire CSA over whichever envelope is shown.

Recovery is how far through its shrink range the sleeve travels to grip the bundle: 100% means it recovers fully onto the bundle (bundle at the recovered ID), less means it grips before fully recovering.

Fill is the summed wire OD area divided by the enclosing-circle area. It's a rough measure of how tightly the bundle packs.

Sources: finished-wire diameters from TE Connectivity control drawings (55A0111, 55M0414; twisted pairs 55A0121, 55A1121, 55M0424, 55M1424); sleeve expanded / recovered inside diameters and nominal wall thicknesses from the TE Connectivity customer drawings DR-25 (rev C2), DR-25-TW (rev A) and RW-200-E (rev A); the 3/32 sizes of DR-25 and RW-200-E from the drawings for the special parts DR-25-NR566 and RW-200-E-NR542 (rev 2).

Disclaimer - don't be a wounder. This tool is provided for guidance only. Bundle diameters are geometric estimates from published wire dimensions, so you are responsible for verifying fit against real parts and the applicable standards for your application. Full Boost Consulting Ltd accept no liability for any loss, damage, injury, or cost arising from the use of this tool or reliance on its outputs.

Built by Full Boost Consulting Ltd

Used it, then built it? Send us a screenshot of the tool (bundle cores and packed bundle), along with the actual measured diameter of your finished bundle. Every real data point helps us improve.

Like the tool? Spotted an issue? Want one built for you, or your team? Get in touch - we'd love to hear from you.

And if it saved you some time, buy us a brew ☕

DISCLAIMER:
DON'T BE A WOUNDER

Replace the current bundle?

FULL BOOST Bundle Sizer

DISCLAIMER:DON'T BE A WOUNDER

DISCLAIMER:
DON'T BE A WOUNDER