Repairing an old Delta 10" Mitre Saw
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- čas přidán 12. 09. 2024
- I got this saw for $20, working, but with a few broken parts. The blade guard didn't retract or extend anymore, the throat plate was chewed up from a lot of use, and the lever mechanism to loosen and tighten the bevel adjustment was broken. The parts aren't overly expensive if I wanted to just buy new ones, but the whole thing only cost $20, anyway, so I figured I'd try fixing it for free with stuff I had laying around. I didn't show it working with a new blade in the end, but after replacing the one that came with it (which was missing several carbide teeth) it works beautifully.
Just thought I'd add that I did the same as you on my guard and it works well. Thanks for your video.
My brake died a few years in- that was about 15 years ago. Has to be in the switch if it’s a motor reversal brake. Just figured that kinda stress would impact motor life so Ieft it. Not as dangerous as with a table saw with no brake.
I have the 12” version of that saw and I’m having problems with it starting and stopping slowly. Basically, when I squeeze the trigger it takes more than a full second to come up to speed, and when I release the trigger it takes 2 to 3 seconds to stop. As recently as yesterday it was working correctly, meaning that when starting it would get up to speed within a half second, and stopping even faster.
My first suspicion was the brushes, but they seem fine. I took the cover off the motor and noticed that when I rotate the armature by hand it turns the blade, but it takes little force to hold the blade motionless and the armature spins with only a small additional force. Does that imply that there is a problem with the reduction gear?
Thanks for an excellent video, and thanks in advance for any insights you can give on my problem.
Hmm. Without being able to see it myself, I can just make a couple educated guesses about the problem. First, I know it seems overly obvious, but I would check the arbor bolt to make sure the blade is firmly tightened to the arbor. Remember, it’s left hand threads. Next, I would strongly suspect the motor brake isn’t working. It’s an additional winding in the motor that opposes the normal rotation of the arbor, but is electrically disconnected when the trigger switch is activated, then connected when the switch is released. The faster the motor is “coasting” when the trigger is released, the stronger it opposes the motors rotation. The trigger switch itself contains the contacts for the normal motor operation as well as the motor brake winding, and is the most likely point of failure. I would focus attention there.
Jeff Newton thanks for the response! I suspected the motor brake but I didn’t understand how it works (I thought it was something mechanical in addition to the motor, I didn’t understand how the motor can brake) your explanation makes it clear. I will check the trigger to make sure the switch is making contact like it should. I can order a replacement trigger switch online for only a few bucks, hopefully that’s the problem.
Hi. Thanks for your video.I got the same one saw. but the blad guard was missing.Another question is the blade is not exactly cut in the middle of the insert. As I noticed that even the new cutting line on the new insert that you did is not exactly in the middle.It shows the right part is bigger or wider than the left side. Is that true? Thanks.
Yeah, on a 90 degree cut the blade lands about 1/4” left of center in the insert. I believe this is a relatively common problem for the blade guard to wear out on this saw, so my guess is that people get annoyed with it and take it off. I’ve seen a few more of the same saw for sale with no blade guard, so I’m guessing that was the reason.
I have the same saw I got from my father. However the nut that holds the blade has rusted shut. I've tried everything to try and get the blade off. All I need is the motor out of it. You have any tips on getting the motor out?
I haven't had to remove the motor for any reason yet, but I did find the arbor bolt to be very hard to loosen at first because of some rust. I think it spent a bit of time outside, and the bolt was tightened very hard. Looking at the motor, it looks like you may be able to remove it, blade and all if you remove all of the Phillips screws from the back of its housing, remove the blade guard, and the handle/trigger. A healthy dose of a good penetrating oil might be easier, if you're able to get it into the threads behind the blade, on the motor side. That's what I did. I can recommend the kind I use for the most difficult situations I encounter: "Mouse Milk" penetrating oil. It's around $9 for a bottle. I hope you can get it removed. If I ever end up removing the motor I'll make a video.
Jeff Newton thanks for the help. I'll see if I can find some of the oil to loosen the bolt up.
I'm sure you already know, but the bolt is left hand threaded, too. Lefty tight... if you're going hard on it to loosen it to the left, it's getting tighter.