digital equipment corporation · maynard, massachusetts
PDP-8 (Straight 8) Computer Cosmetic Restoration

So far the cosmetic restoration has been cleaning and making a new side panel. The power supply restoration and backplane restoration has some more specific information on the cleaning of those components.

For cleaning I start with the gentlest cleaner and work my way up if needed to remove the residue. For general cleaning I start with standard water and household cleaners such as Windex and Fantastic. I then try Goof off 2 (water based) if something stronger is needed. Next is De-Solv-it contractors solvent. This one will damage some inks/paints and plastics so check first. The last is the solvent based Goof Off. It is the most likely to remove stuff you don't want removed. I also sometimes use Soft Scrub, a cleaner with a mild abrasive. The 90% Isopropyl Alcohol is also useful for cleaning parts like heads and some marks/stains can also be removed with it.

When moving on to the stronger cleaners on paint/labels I will test a small area and in a less obvious spot if practical. I try to limit the time it's on the surface. I will also decide if the residue I'm trying to remove looks worse than possibly damaging what it's on. For paint if you use a contrasting color cloth you can normally see if it starts to remove paint before it becomes noticeable on the item.

For the plastic covers I also used Novus plastic scratch remover to polish out some scratches and residue from where something had scraped across them. This product is a couple grades of fine abrasive and a polish.

My computer was missing the side panels that go on the power supply. So far I have made one replacement. The side panels are laminate on plywood with aluminum trim. It's unclear what wood the laminate was imitating. From information online I thought it might be rosewood so I used Formica elegant rosewood. It wasn't a great match to the MARCH machine. Mine is the top panel in the first picture. Click on pictures for a larger version. Pictures of straight 8's at National Museum of Computing/Bletchley Park and Computer History Museum show side panels that look a little closer to mine at least in grain pattern.

The original side panel used aluminum channel around 7/8" wide. That isn't a standard stock size so I used 1/8"x3/4"x3/4" 6063-T52 aluminum angle, 1/2" plywood and 1/16" laminate. The DEC aluminum trim finish is a little different from what I used. I think my side looks pretty good even if it isn't quite right. You can see the side on the computer in my VCF East 2012 pictures.

The following picture links also have descriptions of what is shown in the pictures.

Thumbnail Picture Selector

Current size small. Select picture size for links below   Small  Medium  Large

Deteriorating foam in air filter ( 71K)  Air filter ( 70K)

Next initial inspection Up to straight 8 restoration

Feel free to contact me, David Gesswein djg@pdp8online.com with any questions, comments on the web site, or if you have related equipment, documentation, software etc. you are willing to part with.  I am interested in anything PDP-8 related, computers, peripherals used with them, DEC or third party, or documentation. 

PDP-8 Home Page   PDP-8 Site Map   PDP-8 Site Search