Daniel G

Thanks for helping figure this out. Your comments were very helpful.

Replaced the plug. Saw now works fine again. So it seems did not originally function because neutral prong was already broken inside the plug, so there was an open circuit. During my troubleshooting I should have focused on the plug first. I assumed the plug was OK, it seemed OK, and I did not look at it.

Thanks. Yes, I am going to swap out the tool plug, as I have no choice, the neutral prong is gone. It seems you are suggesting there was high resistance at the point where the prong vaporized. That makes sense, could explain why the prong melted, makes more sense than my idea of “current surge”. But any idea why 1) saw totally did not work with apparently good switch, and 2) had catastrophic failure of neutral prong when I bypassed the switch? I guess here is one possible idea: Neutral prong was already broken, and did not complete the circuit when I was using the switch. Then later, when I bypassed the switch, the prong made a weak, high-resistance connection and was damaged even more, splitting off the prong. Before the prong vaporized, I measured the voltage coming in, and that was OK. But I did not measure that the neutral prong had continuity. Did not imagine there could be a break. I will try replacing the plug, and see if saw then works. Let me know if any other ideas what happened.

Harbor Freight Chicago Electric 10” sliding miter saw. 61972 product id. 5 to 10 years old. Previously worked fine. Used it a lot. Today, when pressed trigger to run, made brief sound, then nothing. Blade turns freely by hand. But does not run when press trigger. Just sits there. Disassembled trigger handle. Easy to do. Trigger presses on a simple switch (see picture), with hot lead in. Tested switch (with no leads connected) with multimeter. Infinite ohms when switch not pressed. Zero ohms when switch pressed. So seems switch functions perfectly. At that point, not sure what to do. Figured it would not hurt to bypass switch. Removed two leads from switch. Plugged in saw. Touched leads together, holding by insulated part of wires. Saw briefly tried to start. Then electric smell. Then noticed that plug neutral prong had melted through (see picture). Most of prong remained in electric outlet. Why did connecting the two hot leads have such an unexpected (to me) effect? I thought connecting the leads by hand would be the same as connecting with the switch by pressing trigger. What did I miss? It seems there was a *big* current surge that melted the neutral plug prong. Any idea why that happened? Any thoughts about what I might look at next to get the saw working again? Besides replacing the power plug.

Having received no replies, I took a few reciprocating saw blades to a big box store, and inserted them into an assortment of reciprocating saws. Every saw had a quick release mechanism, with a variety of designs. And every saw had vertical play, some more than others, but none a lot. My conclusion is that it is normal for the mounted blade to have some vertical play. My guess is that the vertical play is not a problem, and I will be happy with the new saw. However, I'm glad that I still also have my old Makita JR3000V with a bolt, and no vertical play.

Recently bought new Metabo HPT CR13VST reciprocating saw. Have not used yet. Easy to mount supplied 7.5" long blade. No horizontal play when I try pushing / pulling blade away from / into saw body. But mounted blade has some vertical play. In other words, when I push / pull mounted blade up / down, blade rotates around hole at base of blade. The tip moves 5-6 mm (about 0.2 inches). That translates to about 1.5 degrees. Only the blade rotates. Tried some other blades. Same thing, has vertical play. In my Makita JR3000V reciprocating saw, have had years, the blade is rigidly held, no vertical play. The Makita saw has a bolt, hex wrench tightens, totally clamps down on blade. In contrast, Metabo has quick release mechanism, no bolt, instead a pin fits into hole, lets blade rotate a little. Was inconvenient and slow to mount blade in the Makita saw, but not a big deal. The blade was rigidly held, saw works great, blade clamp will last forever (not so sure about Metabo mechanism). The downside of Makita saw was it could not accommodate wider blades, the blade hit against the housing. Questions: Normal for mounted blade to have some vertical play? Does your reciprocating saw have similar vertical play and not cause any problems? Might the vertical play be a problem when Metabo saw functions in orbital mode? Or when blade is in a gap looking for nails to cut? Thanks!