Ten M3x5mm stainless-steel flathead screws for the whole structure
1U length
113.50 mm
Complete skeletonised 1U kit mass
300 g total with flight module and transceiver
First flights by revision
Rev B 2007 (Libertad-1), Rev C 2008 (Delfi-C3), Rev D 2009 (ITU-pSAT1)
In short
Pumpkin Space Systems sells this frame for building a small satellite from commercial parts. It comes in five lengths, from 0.5U to 3U, either as a sheet-metal chassis or as a machined Pro version. A 1U frame is 113.50 millimetres long. Pumpkin says its aims were room inside, low weight and strength.
Pumpkin describes the structure as three major assemblies. Six M3 screws fasten the base plate and four fasten the cover plate. Only the chassis walls change from one size to the next. The aluminium is hard anodised where parts wear and coated with alodyne, a clear chromate finish, so the whole frame conducts electricity.
Application
A CubeSat chassis for building a small satellite from commercial parts. It is offered as a sheet-metal frame or a machined Pro frame, in sizes from 0.5U to 3U, and held together by only ten screws. Helpful for teams that want a flight-ready structure with a defined finish and plating instead of designing their own.
Photos
How it is built
Chassis walls
The standard walls are 5052-H32 aluminium sheet, joined at one riveted edge, and Pumpkin says the one-piece design resists compression and twist. Solid and skeletonised versions are sold, the second with cut-outs for solar cells and sensor views. The Pro version is machined from 7075-T6 billet.
Chassis Walls Assembly
Chassis Walls, solid-wall version (0.5U to 3U)
Chassis Walls, skeletonized version (0.5U to 3U)
Machined chassis components (CubeSat Kit Pro)
Riveted edge of the Chassis Walls
Base and cover plates
Both plates are 5052-H32 aluminium. The base plate closes the end where the motherboard sits and carries one or two separation switches, which tell the satellite it has left its dispenser. Cover plates come in other forms, one for up to four switches and one with an 88 millimetre central cut-out.
Base Plate Assembly (solid-wall or skeletonized)
Cover Plate Assembly (solid-wall or skeletonized)
Separation switches in the base plate (single or dual)
Quad-switch Cover Plate Assembly
Large Aperture Cover Plate Assembly
Screws, rods and spacers
Every fastener is non-magnetic stainless steel. Four threaded rods and aluminium spacers hold the stack of circuit boards in compression. Four small standoffs of 7075-T6 aluminium tie the rods to the chassis.
Chassis screws (ten per structure, M3x5mm flathead)
All fasteners, captive and loose
Threaded rods, M3 stainless (x4)
Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16)
Midplane Standoffs A, B, C, D and four M3x5 mm screws
Feet and solar clips
The corner feet are machined from 7075-T6 aluminium and hard anodised. An option adds spring plungers to them, which push a neighbouring satellite away in a shared dispenser. A set of eight stainless-steel clips holds solar panels on all six sides without extra fasteners, adding 9 grams.
Feet
Separation plungers in the corner feet (option)
Solar Panel Clips Set (P/N 711-00346, 7 + 1 clips)
Payload sections
An adapter plate joins a machined external payload section to the sheet-metal chassis, and a payload cover plate closes the far end. Sections run from 0.5U to 2.5U in length. Both plates are 5052-H32 aluminium, and the section's edge rails are hard anodised.
Payload Adapter Plate
Payload Cover Plate Assembly
External payload edge rails
Where the parts areNumber of parts we have listed in each group
The spacers between circuit boards. The alloy is not given.
The materials by familyHow many of the parts that name a material use each one
Other14
Aluminium9
Stainless steel7
How it connects to other things
Pumpkin's drawing 810-00252 sets out the CubeSat dimensions the kit conforms to. The kit fits Cal Poly's P-POD dispenser, which takes up to 3U. Delfi-C3, a 3U satellite from TU Delft, launched on India's PSLV in 2008 with X-POD dispensers. The earliest flight Pumpkin names is Libertad-1, launched from Baikonur in 2007. GOLIAT flew on the maiden flight of ESA's Vega rocket in 2012.
Used in
Libertad-1 (Colombia, 1U, Rev B)
Launched from Baikonur on 17 April 2007; operated 34 days on primary batteries
HawkSat-1 (1U, Rev C)
Launched from NASA Wallops on 19 May 2009
ITU-pSAT1 (1U, Rev D)
First Rev D kit launched; PSLV-C14, 23 September 2009
GOLIAT (Romania, 1U, Rev D skeletonized)
Vega maiden flight, 13 February 2012; reaction wheels built into the chassis walls
Caerus / Mayflower (payload end, 1U Rev D skeletonized)
Falcon 9, 8 December 2010
Delfi-C3 (TU Delft, 3U, Rev C)
PSLV-C9, 28 April 2008
Radio Aurora Explorer, RAX (3U, Rev D skeletonized)
Minotaur IV, STP-S26, 19 November 2010
RAX-2 (3U, Rev D skeletonized)
Delta II with NPP, 28 October 2011; deployed from P-POD 3
CSSWE (3U, Rev D solid-wall)
Atlas V, ELaNa VI, 13 September 2012
QbX1 and QbX2 (Colony I, MISC 2 carrier)
MISC 2 carrier proves the CubeSat Kit External Payload scheme; Falcon 9, 8 December 2010
Aeneas (Colony I C1B bus, modified MISC 2)
Atlas V, ELaNa VI, 13 September 2012
LMRST-Sat (JPL/Stanford 3U)
ADACS Payload Walls plus 1.5U chassis walls were used; flight outcome not stated on the page
Carries
ISIS Antenna System (AntS)
Dedicated base and cover plates take the third-party AntS deployable antenna
Launched on
P-POD (Poly-Picosatellite Orbital Deployer, Cal Poly)
Compatible deployer; total kit length must not exceed 3U when deployed from a P-POD; RAX-2 flew from P-POD 3
X-POD (SFL/UTIAS CubeSat deployer)
Delfi-C3 (Pumpkin Rev C 3U structure) was integrated with the X-POD deployers on PSLV-C9
RocketPod adapter kit (1U only)
Pumpkin adapter kit compatible only with 1U CubeSat Kits
stainless-steel. Here: Chassis screws (ten per structure, M3x5mm flathead); Threaded rods, M3 stainless (x4) and more. There: Centaur propellant tanks.
Aluminium alloy 7075-T6. Here: Machined chassis components (CubeSat Kit Pro); Feet and more. There: Aft transition structure ring frames and skins.
Aluminium. Here: Structure, three major assemblies; Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) and more. There: Booster LO2 and RP tanks; Propellant feedlines and more.
Aluminium alloy 5052. Here: Chassis Walls Assembly; Chassis Walls, solid-wall version (0.5U to 3U) and more. There: Pumpkin CubeSat Kit structures (sub-1U to 12U SUPERNOVA).
Aluminium alloy 7075-T6. Here: Machined chassis components (CubeSat Kit Pro); Feet and more. There: EnduroSat structures (1U to 6U); EnduroSat 1U structure and more.
Aluminium alloy 7075-T6. Here: Machined chassis components (CubeSat Kit Pro); Feet and more. There: Edge profiles and hot inserts.
Aluminium. Here: Structure, three major assemblies; Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) and more. There: Telescope (structure and mirrors, 3 telescopes).
Aluminium alloy 7075-T6. Here: Machined chassis components (CubeSat Kit Pro); Feet and more. There: Ascent-stage structure (major alloy); Descent-stage main structure (beams, decks, bulkheads).
Aluminium. Here: Structure, three major assemblies; Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) and more. There: Cabin front-face, RCS cluster trusses, decks and bulkheads; Micrometeoroid shield and more.
stainless-steel. Here: Chassis screws (ten per structure, M3x5mm flathead); Threaded rods, M3 stainless (x4) and more. There: Outer shell (heat shield structure); VHF scimitar antennas and more.
Aluminium. Here: Structure, three major assemblies; Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) and more. There: Radial beams; Crushable ribs (x4) and more.
Aluminium alloy 7075-T6. Here: Machined chassis components (CubeSat Kit Pro); Feet and more. There: Thrust structure skin panels; Intertank and more.
Aluminium. Here: Structure, three major assemblies; Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) and more. There: S-IVB forward skirt, aft skirt, thrust structure and aft interstage.
What we do not know
The structure page gives no weight for the bare frame, no load or vibration ratings and no temperature range. It doesn't say which alloy goes with which size, beyond sheet metal against Pro, or which metals plate the contact surfaces. Its copyright line runs 2000 to 2013, so some details may be dated.
The detailed data
What is written above is built from these numbers and quotes. Each row links to the page it was taken from. Get all of it as JSON, or ask our MCP server.
Used in 3 partsStructure, three major assemblies · Through-hole spacers, aluminium, 15.24 mm x 6.0 mm OD (x16) · Through-hole spacers, aluminium, 24 mm x 6.0 mm OD (x4)
Used in 1 partSpring plungers (x2), stubby, Delrin nose (Vlier SSMD-51A)
Material page coming soon
Every part we have
The page names several parts (sheet chassis walls, machined chassis, feet, standoffs, screws, spacers) with a material for each, but gives no itemised parts list with part numbers per material. Components, suppliers and links were added from public sources. A material is left blank where no source states it.
Threaded rods, M3 stainless (x4)Columns that carry the module stack, each affixed to the Base Plate Assembly and capped with an M3 nut“M3 SST Threaded Rod of length”
M3 stainless nuts (x5) and split washers (x5)Cap the rods and keep the stack in compression“M3 SST Nut”
Stainless steel (grade not stated)stainless-steel
—
Supplier: Pumpkin, Inc.
M3x5 mm flat Phillips screws (x5) and M2.5x6 mm pan Phillips screws (x5), stainlessKit screws; M2.5 screws come with M2.5 split washers“M3x5mm SST Flat Phillips Screw”
RBF pin access area and optional data port access areas (8 places)Access windows on the faces for the RBF pin and umbilical ports“OPTIONAL DATA PORT (8 PLACES)”
MIL-A-8625F Type III Class 1 (hard anodize, 0.0005-0.0008 in) · Aluminium chassis components, feet, midplane standoffs
MIL-DTL-5541F Type II Class 1A (non-hexavalent chromate, RoHS compliant) · Aluminium chassis components (alodyne finish)
CubeSat Design Specification (CDS) · Surface plating requirement for contact surfaces; Pumpkin drawing 810-00252 is its control drawing
What the sources leave out
No part-number-to-material table: the system chart gives Pumpkin part numbers and masses (e.g. 703-xxxxx chassis walls, 711-xxxxx clips kits) but the text layer does not tie numbers to parts reliably, so none are recorded for the chassis. Material notes on the payload drawings are 'SEE NOTES' and the notes are not published. Materials of solar panel clips, base plate assemblies, RBF pin/bracket, spring plungers and the cover plate are not stated. Temper/alloy of the feet and standoffs is given but not of the base plate or clips. The control drawing 810-00252 is the CDS-derived interface drawing (it names a Vlier SSMD-51A spring plunger with Delrin nose), not a Pumpkin part list, so it is not recorded as a Pumpkin part. Alodyne is cited as a finish but no alodyne specification is given on the flyer; the structure page cites MIL-DTL-5541F. More detail: Pumpkin's public pages (the structure page is marked 2000-2013) do not give the Chassis Walls or Pro Chassis Walls masses and dimensions in text; those are in the 'CubeSat Kit Chassis datasheet' PDF that was not reachable from the store pages. The system chart ties part numbers to names in a layout that cannot be read reliably for the five chassis sizes, so chassis part numbers are not recorded (703-00288 to 703-00292 and 703-00243 to 703-00287 appear on the chart). Not stated: rivet material, foot and plunger part numbers beyond the control drawing, hard-anodize thickness per part other than the structure-page MIL-A-8625F callout, solar panel substrate and cell supplier, plating metal for conductive platings, and the Pro chassis mass. Libertad-1 and HawkSat-1 launch vehicles are not named on the In Space page. The control drawing dates from 2003 and still shows a 1 kg limit; the CDS Rev 14.1 limits are in the extra specs. More detail: Pumpkin's public pages (the structure page is marked 2000-2013) do not give the Chassis Walls or Pro Chassis Walls masses and dimensions in text; those are in the 'CubeSat Kit Chassis datasheet' PDF that was not reachable from the store pages. The system chart ties part numbers to names in a layout that cannot be read reliably for the five chassis sizes, so chassis part numbers are not recorded (703-00288 to 703-00292 and 703-00243 to 703-00287 appear on the chart). Not stated: rivet material, foot and plunger part numbers beyond the control drawing, hard-anodize thickness per part other than the structure-page MIL-A-8625F callout, solar panel substrate and cell supplier, plating metal for conductive platings, and the Pro chassis mass. Libertad-1 and HawkSat-1 launch vehicles are not named on the In Space page. The control drawing dates from 2003 and still shows a 1 kg limit; the CDS Rev 14.1 limits are in the extra specs.
