• Please review our updated Terms and Rules here

H960 rack

C

ComputerGeek

Member
Joined
Dec 9, 2017
Messages
21
I want to put some DEC equipment in an H960 rack. The problem is that I don't own one. I would like to build my own but I can't find the proper measurements in manuals and there doesn't seem to be anything online. Does anyone have measurements of the rack or can someone take measurements? Thanks.
 
There are a lot of dimensions on the diagrams in the H950 section in the Logic Handbooks. I am looking at the 1973-74 edition on bitsavers. The H960 is an assembly of the H950 inner rack frame plus various side panels and the like.

Where is your location? Someone near you may be willing to give you something that would work. It may not be an H950 (could be newer) but still DEC.

Lou
 
Last edited:
Thanks for the response.

I didn't even think to look there. The handbook does give some measurements but not all. I would prefer to have every single measurement possible but I guess it doesn't have to be exact.

I live in Canada, I don't know if I'll be able to find anything close by.
 
It's more or less a standard 19" Rack, except that it is not as deep as the usual ones are.
I can measure it when I'm back home....
 
In my experience, 19" racks are expensive to purchase new or if shipping is involved. However, I have had luck with local computer network/datacenter installations that were downsizing (same service can be provided with fewer racks) and often let their racks go away for free or next to nothing. Also check local steel recyclers, they may sell you racks for cheap.
 
A while ago I repopped some H960 rack hardware fixtures including imitations of the original stabiliser feet.
I guess it doesn't help you too much but for what it's worth, here is the CAD drawing I did for helping me with the feet.

A new-from-scratch H960 rack could be made up in kit form with CNC folding and punching, after using something like SolidWorks to produce the flattened-out sheetmetal profiles. The problem is it would be astronomically expensive to have made.

Apart from modern racks being much much deeper, the use of square holes and often of heavier construction, the H960 has the front-back aligned surfaces on the inners of the verticals (with matching RU holes) that modern racks have a bit different.

DEC_H960_lower_right_corner.jpg
If that is too small the full-size image is at http://web.aanet.com.au/~malikoff/pdp11/DEC_H960_lower_right_corner.png

I converted a (IIRC) 18RU modern rack into a PDP-11 rack by splitting it into a top and bottom then welding the front and back verticals together and making new rear verticals from an old angle-iron bed frame, drilled at RU spacings.
 
Steve, that is a great sketch (but I have to convert to Imperial units!)

Does anyone have a 3D model or similar sketch for the H950-LB plastic logo plate that goes at the top of the rack? We have racks, but the logo mastheads have all been stolen, likely as souvenirs.

Lou
 
I have been working on the masthead for a while and indeed will have something that satisfies the 'six foot rule' (ie. it looks good from 6 feet away, and probably even closer).

The 3D panel model is in progress and the artwork has been complete for quite some time now. I visited a sticker printing shop a while back and talked to them about what I needed, and got some samples but I'm not too enthused with the print quality of a stick-on insert into the masthead plate, it looks a bit dotty.

Doing some test vinyl cuts on my CNC stencil cutter isn't too bad and when I get around to buying some vinyl transfer paper I'll cut a mask for silk screen printing tests.
If I produce any, the sale cost would be mostly to cover raw material purchases (decal sheet, vinyl, paints, filament, styrene sheet etc etc) if I factored my actual time in then no-one would want a repo, you'd might as well spend the money on finding originals.

Same goes for the repopped H960 stabiliser feet where my two pairs were one-offs (a steel load-bearing frame with aesthetic 3D printed leg cover that matches the original leg casting) but if anyone expressed interest then I would consider making the cutting, bending, drilling and welding jigs to make a large batch.
 
I also started designing my own rack in 3D.
Here are a few views of my unfinished work with Solidworks for a 2nd small rack for my pdp11/40.

DSC01281.jpg
solidworks.jpg
3D PDF: http://www.2jo.de/vcfed/H960.PDF

In the construction are still missing the brackets for the rollers and a few other small sheet metal parts.
The parts are to be lasered and bent by an external company here in Germany. Mostly I use Tailorsteel.
If this has been delivered, then only need to weld a little things and attach a few pop rivets.

Currently, the problem is the closed bent edge on the front of the upper sheet metal plate. The company can not deliver that.
So I have to redesign that.
 
Nice rack design. Are there gussets internally, to reduce lateral twisting? For the front piece, consider a piece of say 2.5mm thick wall RHS tube, it usually has radiused corners. You will likely pick up an offcut at a metal supply shop.
 
You must log in or register to reply here.
Back
Top