Thread
Mac Plus cooling
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?
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
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
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
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.
If you want a Kensington SystemSaver PM me, I think I've got one in my garage.
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).
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.
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.
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.
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.
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).
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
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
heh, never thought about that before
It looks like a neat hat for ones Mac.
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
Perhaps one could make up a box that mounts in the handle cavity on top of the Mac and contains a small 12V fan
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.
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.
yea I wouldn't run a fan off the adb ports, 2 fuzzballs get stuck in it and your out of luck
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.
i would still be leery of driving any motor off of a port, they are not generally made for decent amperage, and putting your finger on a decent fan can draw double digit amps, yea that is a extreme worst case, but when connecting it to a port made to deal with at best a few hundred miliamps...
edit: plus the electrical noise, and reverse emf, and becoming an ac generator when spinning down and ... just use drive power (imo)
edit: plus the electrical noise, and reverse emf, and becoming an ac generator when spinning down and ... just use drive power (imo)
The 400/800/1440K drive which is powered off of the floppy port, and it is essentially a motor that can be very active during file transfers. I've never seen a sticky drive overload the bus, so there must be safeguards in place, since common disk accidents would damage the Mac in the way you suggest and I just never saw that happen. And the port can only power a DC fan.
The serial port was never designed to run a drive, so I would be more concerned about running a motor off of that.
Plus, I'm not sure how using a port as a power source is any different than the common practice of taping into various power access points inside the Mac to power internal AC & DC fans.
port = connection to some other logic device, serial printer whatever, connect a inductive load to logic and see how much it can handle }
drives usually connect to the power supply in a direct fashion, and yea tap away if it looks like something you can drive a lamp from, that is why power supplies have lots of beefy caps and large diodes
macs of course dont have different floppy power connectors, they just pipe the power up the ribbon cable but its connected to the power supply, I always kinda thought it was shady that 30guage wire has a lot of resistance and can only handle ~800ma before it vaporizes somewhere
drives usually connect to the power supply in a direct fashion, and yea tap away if it looks like something you can drive a lamp from, that is why power supplies have lots of beefy caps and large diodes
macs of course dont have different floppy power connectors, they just pipe the power up the ribbon cable but its connected to the power supply, I always kinda thought it was shady that 30guage wire has a lot of resistance and can only handle ~800ma before it vaporizes somewhere
Convection cooling was such a monumentally bad idea that Jobs brought it back in the G3 iMacs. 
It only goes to show that a bad idea isn't bad when the boss thinks of it. 8-o
It only goes to show that a bad idea isn't bad when the boss thinks of it. 8-o
So it would be no different tapping the 12V supply off that, than tapping the one off the internal floppy, surely.
depends like I said the power is on the ribbon cable, has a max of ~800ma for the wire, who knows what the port can really handle, whats the floppy drive suck down, whats the fan suck down?
mac's especially early ones, have pathetic current sources available to the user, your gamble
mac's especially early ones, have pathetic current sources available to the user, your gamble
I don't recall any serious problems with the iMac. I have a friend with one of the original iMacs that is crammed into a cluttered corner in an un-airconditioned house and it's still going strong today, never having had a repair.
I have a Plus built with the proper SE grade components in 1990 which has never had a repair and is still going strong, despite having been used during its most productive years in a tiny un-airconditioned office surrounded by clutter.
None of the original PowerBooks ever had a fan. In fact I have a PowerBook Duo 2300 that has never had a repair and is still going strong.
Televisions, particularly the early ones which were crammed with vacuum tubes and heated up like ovens, never had fans. My grandmother had a particularly well made Magnavox from the 60s, that ran hotter than any compact I ever felt, which ran flawlessly for over 40 years.
If a product was designed to facilitate convection or conductive cooling, there is no reason to consider it a bad idea. The compact seemed to have been adequately designed to handle this type of cooling. The problem was cheaper underpowered components than specified (thanks to bottom-line Sculley) and to a lesser degree, improper use.