Mac Plus cooling

[macpaint2009]

I've read that since the Plus didn't have a fan, it was somewhat common for it to overheat and have PSU issues. The last time I used one, I was 7, but I've recently acquired a new one that I plan to operate for long stretches of time in an already hot environment (>95 F), and I'm wondering if I need to be prepared for trouble. How concerned should I be about this ahead of time, and what are the recommended mods to keep it cool?

 

[equill]

Buy a Kensington Saver (or similar) cooler (which is powered separately from the Mac).

Install an exhaust fan into the case, taking careful note of its power-requirements vis-à-vis the Mac's analogue-board capability.

Train the airstream from an electric fan across the top surface of the Mac.

Make a passive-ventilator chimney of cardboard, to aid the convective cooling built into the Mac.

That you are starting from a high ambient temperature is a disadvantage, so, if you cannot lower the ambient temperature, higher throughput of air is your most obvious response.

de

 

[Apostrophe]

Train the airstream from an electric fan across the top surface of the Mac.

That's what I do with my SE whose fan doesn't work too well (yup, it's the rat-cage fan). I just focus the air from an external fan onto the side where the analog board is, and it works wonders for keeping it cool.

-Apostrophe

 

[Franklinstein]

That's what I do with my SE whose fan doesn't work too well (yup, it's the rat-cage fan)

I've only seen one SE with the noisy and fairly useless squirrel-cage fan, so of course I added it to my collection, where it is undoubtedly the laughing stock of my other SEs equipped with the little box fans.

 

[Scott Baret]

If you want a Kensington SystemSaver PM me, I think I've got one in my garage.

 

[Charlieman]

Install an exhaust fan into the case, taking careful note of its power-requirements vis-à-vis the Mac's analogue-board capability.

Back in the day, extra cooling systems for the Mac Plus and earlier worked best if they were external devices drawing air through the top of the system unit (eg Beck-Tech Fanny Mac). Putting a fan inside the system box impedes air flow and may make things worse.

Needless to say, the Plus will work a lot better if the OP refurbishes the analogue board (see previous threads).

 

[Mac128]

Putting a fan inside the system box impedes air flow and may make things worse.

So you're saying Larry Pina's recommendation to add a fan inside the case should not be the primary method considered? Certainly an external fan helps preserve the rarer older Macs in their original condition.

 

[JDW]

Putting a fan inside the system box impedes air flow and may make things worse.

I don't believe Charlieman's statement is speaking against cooling systems like this GCC fan simply because the first sentence in his post talks about the benefit of "drawing air up through the top."

The original Macintosh convection cooling design was such that cooler air would come up through the bottom of the case and the warmer air would go out the top. The GCC fan shown in my photo, used on the HyperDrive, was little more than a slight modification of the original cooling concept. The GCC fan simply pulled more cool air from the bottom of the case and out through the top. I think this was actually a better approach than how Apple later cooled the SE and SE/30, with a fan that did not sit at the top of the case. As a result, the SE series Macs allow hot air to float up to the top of the case and stay there. Even if one argues that the air inside circulates, the fact is that the top of my Mac SE/30 gets quite warm even with the fan running, meaning that a lot of hot air is staying in that pocket at the top of the case (staying there because there are no vents whatsoever at the top). Had there been vents at the top with a fan pulling air out those vents, I suspect the SE series would run cooler.

The keywords to cooling old Macs are "warmer" and "cooler," not "warm" and "cold." Because even if you have a great fan/cooling system in your old Mac, how much cooling will you really get if you are trying to use your Mac in a hot room, with all the windows closed, on a summer day where the room temperature rises to 90 degrees F? Indeed, having the A/C turned on is a recommended approach for an old Mac, regardless of whether they have a fan or not. Because remember, the original concept was to have "cooler" air come up from the bottom through the top. But if there is no "cool" air in the room to begin with, you are basically circulating hot air.

So perhaps the best solution is to keep your operating environment as cool as possible. I'm not say an old Mac would not benefit from a fan at the top of the case. But keeping the A/C turned on in your Mac room during the summer time is a must.

 

[Charlieman]

The GCC fan for the HyperDrive is a lot more elegant than most internal fan solutions for the 128K/512K/Plus. If you take a look at some of the exploded diagrams accompanying 1980s adverts for internal cooling products and hard disks, you have to agree that some are quite scary.

It would be lovely to get hold of some of these coolers and put them through their paces, but they aren't common and I can't justify buying them for use in the UK. I do have a Kensington Cooler for my US spec IIgs with accelerator -- a model which truly does need extra cooling.

 

[trag]

Make a passive-ventilator chimney of cardboard, to aid the convective cooling built into the Mac.

http://www.io.com/~trag/Chimney/Chimney0.JPG

http://www.io.com/~trag/Chimney/Chimney1.JPG

http://www.io.com/~trag/Chimney/Chimney2.JPG

http://www.io.com/~trag/Chimney/Chimney3.JPG

 

[Scott Baret]

Ah, the MacChimney! There used to actually be a company that sold those when the Plus was still being produced. Many people swore by them, especially those who were sensitive to the noise fans created (the author of the first few Mac Bibles, Arthur Naiman, was one of those users and wrote extensively about the MacChimney in the older Mac Bibles).

 

[joshc]

This is cool, didn't know about it before.

This Japanese page has some information and pictures about cooling the 128/512K Macs:

http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.mactechlab.jp%2Foldmac%2F2070.html&sl=ja&tl=en&history_state0=

More info about the MacChimney. Specifically, these are scans from the Second Edition of the Macintosh Bible:




http://www.flickr.com/photos/92704948@N00/275104234

 

[Osgeld]

heh, never thought about that before

 

[Paralel]

It looks like a neat hat for ones Mac.

 

[Bunsen]

Onoes, the hats are back.

Perhaps one could make up a box that mounts in the handle cavity on top of the Mac and contains a small 12V fan

 

[TheDoctor]

Onoes, the hats are back.
Perhaps one could make up a box that mounts in the handle cavity on top of the Mac and contains a small 12V fan

You mean like this?

 

[Bunsen]

Yes, like the well-know Kensington System Saver, thankyou so much, I'd never heard of them

I meant homebrewing one that doesn't require the mains power supply and consequent excessive size. Flush with the top of the Mac and no massive protrusion out the back either. A simple, small box with a 12V fan - perhaps underpowered at 5V off the ADB port, or off a disk drive power splitter from inside.

 

[Osgeld]

yea I wouldn't run a fan off the adb ports, 2 fuzzballs get stuck in it and your out of luck

 

[Mac128]

perhaps underpowered at 5V off the ADB port

No ADB port on the Plus. I would run it off the external disk drive, or serial ports, both of which have 12V output. Not sure about SCSI.