Hugo Holden
Veteran Member
A recent thread mentioned about how the 1541 drive with the internal power supply tended to run hot. So I wondered about my recently acquired SFD1001.
I had been using it for a few hours and it certainly does run very hot from the power supply area. It relies on convection cooling taking the air in at the bottom vents and leaving at the top. I could feel very hot air slowly coming out the top vents. It is not helped by the fact that the rubber feet on the unit are not very tall and the lower surface sits close to the bench surface and that problem is aggravated if the drive is on a soft mat.
Looking inside the drive, there was little room underneath to add a cooling fan, but some hope on the top.
I found I could make a satisfactory mounting system, by removing two of the pcb's mounting screws and replacing those with metric hex posts and mounting the fans on those, immediately below the top air vents.
I chose some 50 x 50 x 11mm thick 12v cooling fans and was able to mount them so they sit about 1 to 1.5 mm above the top surfaces of the IC's in the region below the upper case cooling vents. They are powered from the 12V supply on the front connector on the pcb.
To join the two fan bodies together I use a piece of 1/4" wide and 1.6mm thick brass plate, with 3mm threaded holes. The holes were tapped with a taper tap, not quite the whole way through, so the 10mm metric retaining screws, whose heads sit in the fan mounting hole recesses underneath, tighten up in the thread just as they tighten the metal plate to the fan body.
Also I made a small piece of pcb, 22mm x 25mm to receive the fan wires and support a pin assembly for a plug.
It only takes 2 screws to un-mount the whole double fan assembly and unplug it. There are no permanent changes to the SFD1001 at all.
I attached the pcb assembly to the fan bodies using 3-48 1/2 inch long screws, nuts & spring washers. They needed to be a low profile head and a nut that would fit inside the fan hole recesses underneath.
The 55 mm long brass strip is attached to the 20mm post with a 6mm long 3mm dia countersunk head metric screw. The idea being to keep the profile low as there is not much clearance. This whole twin fan assembly sits no higher than the surface of the main heat-sink, so like that, it clears the internal housing.
Now when I run the drive I can feel high speed only tepid air existing the case top which is much better. At some point I will put in a temp probe and find the difference with & without the fans plugged in. But it is already obvious it is a substantial improvement.
I kept a record of the geometry of the assembly, in the event of it being of use to anybody else wanting to add cooling to their SFD1001. The useful 1/4' wide & 1.6mm thick brass plate is made by K&S Engineering in Chicago, IL.
I had been using it for a few hours and it certainly does run very hot from the power supply area. It relies on convection cooling taking the air in at the bottom vents and leaving at the top. I could feel very hot air slowly coming out the top vents. It is not helped by the fact that the rubber feet on the unit are not very tall and the lower surface sits close to the bench surface and that problem is aggravated if the drive is on a soft mat.
Looking inside the drive, there was little room underneath to add a cooling fan, but some hope on the top.
I found I could make a satisfactory mounting system, by removing two of the pcb's mounting screws and replacing those with metric hex posts and mounting the fans on those, immediately below the top air vents.
I chose some 50 x 50 x 11mm thick 12v cooling fans and was able to mount them so they sit about 1 to 1.5 mm above the top surfaces of the IC's in the region below the upper case cooling vents. They are powered from the 12V supply on the front connector on the pcb.
To join the two fan bodies together I use a piece of 1/4" wide and 1.6mm thick brass plate, with 3mm threaded holes. The holes were tapped with a taper tap, not quite the whole way through, so the 10mm metric retaining screws, whose heads sit in the fan mounting hole recesses underneath, tighten up in the thread just as they tighten the metal plate to the fan body.
Also I made a small piece of pcb, 22mm x 25mm to receive the fan wires and support a pin assembly for a plug.
It only takes 2 screws to un-mount the whole double fan assembly and unplug it. There are no permanent changes to the SFD1001 at all.
I attached the pcb assembly to the fan bodies using 3-48 1/2 inch long screws, nuts & spring washers. They needed to be a low profile head and a nut that would fit inside the fan hole recesses underneath.
The 55 mm long brass strip is attached to the 20mm post with a 6mm long 3mm dia countersunk head metric screw. The idea being to keep the profile low as there is not much clearance. This whole twin fan assembly sits no higher than the surface of the main heat-sink, so like that, it clears the internal housing.
Now when I run the drive I can feel high speed only tepid air existing the case top which is much better. At some point I will put in a temp probe and find the difference with & without the fans plugged in. But it is already obvious it is a substantial improvement.
I kept a record of the geometry of the assembly, in the event of it being of use to anybody else wanting to add cooling to their SFD1001. The useful 1/4' wide & 1.6mm thick brass plate is made by K&S Engineering in Chicago, IL.