IMSAI I-Series (IMSAI 8080) Cabinets
The I-Series cabinet is the iconic “IMSAI 8080” design by Joe Killian.
There were essentially two versions of the cabinet. The first one used a few PEM nuts and mostly #6×¼" sheet metal screws.
The I-Series cabinet is based on the later original versions with all PEM nuts.
By late 1976, all shipping IMSAI 8080 cabinets were these versions.
The I-Series cabinet kit comes in 8 sheet metal pieces and can be assembled by just about anyone with a #2 Phillips screwdriver in less than an hour.
It comes with a finger guard for the fan cutout, a power entry module, and eight rubber feet to support the heaviest power supplies.
It also comes with a printed User Manual that may be transferred to a binder.
We have made a few improvements over Joe’s original design, most of which were enabled by newer technologies and standards.
- Replacing the wrinkle finish paint with a very durable textured powder coat finish.
- Adding a C14-standard power entry port to accept power cords from any country.
Of course, the original captive gray 8-foot long NEMA-15 power cord is available as an option.
- Replacing four of the DB-25 back frame cutouts with six DE-9 cutouts.
- Adding a new set of card frame mounting holes in the front and back frames to allow the card cage to be raised slightly to better handle IEEE 696-standard cards.
The new power entry port is compatible with any IEC C13 electronic equipment power cord.
Unless you order the I-8080-PC with the captive US (NEMA-15P) power cord, your cabinet kit will not come with a power cord.
Many of our customers have drawers full of extra power cords.
Even if this is not the case for you, there are too many options for us to keep stocked based on your country and personal preferences.
Many local electronics stores sell power cords.
If that is not an option for you, we suggest you go to
McMaster-Carr
and choose one for your country and personal preferences.
Complete Kits
Order one from the list below. The kits are complete with everything you need except solder and tools unless otherwise stated.
They even come with a nice printed user manual. Be sure to hover over any
icons for more information.
[†] Marked products are heavy or ship in a large box.
To give you the best possible shipping rates, you will be billed for the shipping separately.
If you have items in the cart that are not marked as heavy or large, you will be charged for shipping those during checkout.
Contact Us in advance if you want to get the current shipping rates for your items and destination.
Most builders won’t need anything else besides one of the above complete kits.
To skip over the options go to More Information to get links to useful resources.
If you're an advanced builder and want to see all the options, read on.
Options
| Description | Part Number | Availability | Unit Price (USD) | Quantity | Ordering |
10 card guides (5 slots) for IMSAI cabinet  | CG 10 | In stock | $22.00 | | |
Fan, AC, 115 V, Original IMSAI model | FM | 6/15/2025 | $69.00 | | |
| Fan, DC, 12 V, 55 CFM | FM 12 | 10 day lead time | $19.00 | | |
| Fan, AC, 230 V | FM 230 | 10 day lead time | $49.00 | | |
| Fan, AC, 115 V, Generic | FM G | 10 day lead time | $49.00 | | |
| Fan, AC, 115 V, Quiet (55 CFM) | FM Q | 10 day lead time | $49.00 | | |
Parts
The IMSAI cabinet parts are designed to fit with all existing IMSAI cabinets starting with the “PEM Nuts” cabinets.
These are most easily identified by the power supply on a large printed circuit board with two pair of computer-grade
electrolytic capacitors connected by a rectangular aluminum piece.
| Description | Part Number | Availability | Unit Price (USD) | Quantity | Ordering |
| Cabinet Fan Finger Guard, 3-ring Metal (Rev. 1) | 70-90000000 | 10 day lead time | $3.00 | | |
| Cabinet Fan Finger Guard, 6-ring Plastic (Rev. 2) | 70-90000001 | In stock | $3.00 | | |
| IMSAI 8080 cabinet front frame, Rev. 3 | 92-30003230 | In stock | $128.00 | | |
| IMSAI 8080 cabinet card frame, Rev. 3 | 92-30003330 | In stock | $86.00 | | |
| IMSAI 8080 cabinet back frame, Rev. 5 | 92-30003450 | In stock | $111.00 | | |
| IMSAI CP-A switch escutcheon, Rev. 2, powder coat | 92-30003521 | In stock | $62.00 | | |
| IMSAI 8080 cabinet cable clamp, Rev. 1 | 92-30003610 | In stock | $33.00 | | |
| IMSAI 8080 cabinet base plate, Rev. 2 [†] | 92-30003720 | In stock | $150.00 | | |
| IMSAI 8080 table top cover, Rev. 1, powder coat [†] | 92-30003811 | In stock | $349.00 | | |
| IMSAI 8080 cabinet high Voltage caution label | 92-30005110 | In stock | $6.40 | | |
| I-Series Cabinet Rev-1 user manual | UM-I-8080 | 10 day lead time | $19.00 | | |
[†] Marked products are heavy or ship in a large box.
To give you the best possible shipping rates, you will be billed for the shipping separately.
If you have items in the cart that are not marked as heavy or large, you will be charged for shipping those during checkout.
Contact Us in advance if you want to get the current shipping rates for your items and destination.
Links
Please read the rest of this section for additional product information,
especially if you are planning to install individual cabinet parts in an existing system.
System Compatibility
The I-Series cabinets are an enhanced version of the 1976 second-generation cabinets,
which was the overwhelming majority of units shipped.
We took the opportunity to tweak a few things as enumerated in the introduction.
With the exception of the CP-A switch escutcheon, table top cover and the cable clamp,
every cabinet piece was updated to make a better-fitting and more functional cabinet.
Still, the cabinet pieces are compatible with production units dating back to 1976.
The most notable change is the color of the chromate finish.
Earlier production metal was either clear or yellow chromate.
The current production is more gold in color due to recent chemistry changes.
The next most notable is the back frame, which has been extensively reconfigured but still retains much of the original layout.
First-Generation Cabinet Compatibility
Much to our surprise, there has been quite an interest in cabinet parts.
Especially unexpected are inquiries about compatibility with first-generation cabinets.
This section discusses the implications of mixing our new production parts with a first-generation cabinet.
Note that the cable clamp, CP-A switch escutcheon, and the table top cover are essentially the same as the first-generation production.
Base Plate
The base plate has more mating parts than any other part, so replacing it in a first-generation cabinet has the most implications.
They are:
- Backplane (Mother Board)
- The first-generation mother board mounting system consisted of a metal receiver plate to which the mother board mounted with fibre washers and sheet metal screws.
This assembly was then mounted to the base plate with six sheet metal screws.
Mounting the mother board in a second-generation base plate may be done by simply mounting the mother board assembly to the base plate as it was originally,
or by replacing that mounting system with the second-generation system of standoffs, shoulder washers, and nylon machine screws.
- Power Supply
- In most cases, the power supplies in first-generation cabinets was mostly hand-wired with the large capacitors mounting to the base plate on circular clamps.
In all but the first few units from 1975, the power supply components can be successfully transplanted to a new base plate.
In rare cases, you may have to drill new mounting holes in the base plate to accommodate the power supply components.
- Front Frame
- A first-generation front frame is mounting compatible with a second-generation base plate with one minor exception.
The front frame’s feet which are near the base plate’s side flanges each have two mounting screws.
The spacing of these mounts was reduced by ⅛-inch for the second-generation frame due to the switch from sheet metal screws to PEM nuts and machine screws.
You can probably get away with only using the front set of sheet metal screws (that’s what we did with one of our first-generation front frames).
You can drill out two new holes in the base plate for the two moved sheet metal screws, or you can modify the feet to use the narrower screw arrangement.
- Back Frame
- A first-generation back frame should mount in a second-generation base plate by simply replacing the four sheet metal screws with
#6-32 × 5⁄16-inch Phillips pan head machine screws.
- CP-A Switch Escutcheon
- A first-generation CP-A Switch Escutcheon should mount in a second-generation base plate by simply replacing the four sheet metal screws with
#6-32 × 5⁄16-inch Phillips pan head machine screws.
Front Frame
Because the front frame uses five PEM nuts to mount into the base plate, those sheet metal screws will need to be replaced by
#6-32 × 5⁄16-inch Phillips pan head machine screws.
A second-generation front frame is mounting compatible with a first-generation base plate with one minor exception.
The front frame’s feet which are near the base plate’s side flanges each have two mounting screws.
The spacing of these mounts was reduced by ⅛-inch for the second-generation frame due to the switch from sheet metal screws to PEM nuts and machine screws.
You can probably get away with only using the front set of sheet metal screws.
You can drill out two new holes in the base plate for the two moved sheet metal screws.
Back Frame
A second-generation back frame should mount exactly the same as the original did.
Card Frames
Because the card frames use PEM nuts to mount into the front and back frames, those sheet metal screws will need to be replaced by
#6-32 × 5⁄16-inch Phillips pan head machine screws.
|