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Buying nuts and bolts?

Can someone point me to somewhere where I can buy nuts and bolts? I need them to be up to a few cm long, and about small enough to fit through the hole in a TO-220 transistor. 
I tend to use them a lot, not just for fixing transistors to heatsinks, but my local hardware stores don't have them

Also, I'm looking for those small plastics bits (look like a very small and short bit of pipe) that fit into the TO-220 transistor's hole, before you put the bolt in, electrically isolating the transistor tab from the bolt and the heatsink.

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rickharris4 years ago
He is Australian - The internet should give you a wide variety of local stockists - Most companies who stock the transistors will stock the hardware to go with them.

framistan4 years ago
I have had a LOT of experience mounting TO-220 transistors and have a suggestion for you. If you use a screw through the TO-220 heatsink, you will have problems occasionally with the device SHORTING to the heatsink. This will occur on devices such as an LM317 voltage regulator which MUST have an insulator between the device and the heatsink. However other regulators such as the LM7805 (5volt reg) do not have this problem because the metal tab of the regulator is the ground pin (same as MIDDLE pin) of the device. So it doesn't matter if it touches ground anyway. I have found that the SLIGHTEST metal protrusion around the hole you drill in the heatsink will often short the device to ground. Therefore, after drilling the hole, clean it up by scraping the hole to remove any metal shaving sticking up around that hole. The better mounting method is to NOT USE the screw through the hole mounting method. Instead, use the mounting bracket method which uses a hole drilled ABOVE the device and a plastic tab holds the device down. Unfortunately, I have not found a source for these kinds of mounting tabs yet. I have tried to include a picture of the tabs i am suggesting is best because they don't require the hole and screw that often cause problems.
Hope this helps.
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What sort of quantities are you looking for? The large electronics supply companies like RS and Farnell stock a good range of fixings, as well as other heatsinks and mounting hardware. However, many of the parts may be in fairly large packs.

You might want to see what some model engineering, clock repair or R/C shops have, but these may be relatively expensive, and probably won't have any of the insulation.

If you get through a lot (say 100+ of each at least) it might be worthwhile asking some specialist fasteners suppliers.
.Unknown. (author)  The Skinnerz4 years ago
Yeah, rickharris is right about me being Australian
Thanks for the input though, still appreciated
+1. Some great ideas in there.