My Hitachi has a mind of its own (and Rotary advice)

audicoupej · 12-04-07, 08:10

So, several months ago my Hitachi rotary would act funny. It would either turn off until I lifted the pad from the paint or it would speed up to full speed on it's own until I let go of the trigger. (Never had any accidents since you could hear it about to speed up) This happened very intermittently so I figured it was a power surge or something. Here in NoVa we get brownouts during the summer months.

Well it has been fine for the last few months (although not used all that much). Sunday I was trying to polish an Accord and it started doing it about every minute or quicker.

I have had it over a year so I am out of warranty. I plan on taking it apart and seeing if I can fix it. It doesn't seem like the brushes are worn, but more of a switch problem. It does it with the trigger locked and with me just holding the trigger.

Has anyone had any similar experiences? If so what did you do? I realize I should have sent it back when it first happen but it was not very often so I didn't give it much thought.

If I cannot fix it I am debating what to get next.

Choices are:

Hitachi from the trading post (There are a few good deals currently, so this would be my cheapest option)
Makita
Flex

The Makita and Flex are close in price. My grandfather has a Flex wet polisher that he uses for grinding terrazzo when he has a small patch area. It's used in construction, takes a beating, and has been a durable machine for him. It is a few pounds heavier than the Hitachi and Makita though.

Thanks for your help

SpoiledMan · 12-04-07, 08:16

The Hitachi has a FIVE (5) year warranty.

brwill2005 · 12-04-07, 08:26

If may have electronic speed control. If the chip or circuitry for that goes bad, it could explain the erratic speed. Have you thought about the Metabo? It is an excellent machine and well worth the price because of its smaller size and weight.

audicoupej · 12-04-07, 08:27

Quote:

Originally Posted by SpoiledMan

The Hitachi has a FIVE (5) year warranty.

I tried looking it up yesterday and everything said 1 year, but you are correct. I just checked the Hitachi website. Thanks SpoiledMan! You just made my day.

audicoupej · 12-04-07, 08:28

Brad, I hadn't looked at the Metabo, but will consider it if I cannot get my Hitachi covered under warranty. Thanks for the advice.

SpoiledMan · 12-04-07, 08:38

If both machines were the same price I'd buy another Hitachi before a Metabo. The Metabo runs hot as all hell even at medium speeds with wool pads.

brwill2005 · 12-04-07, 08:38

Feel free to come up to Loudoun County and try mine out. My Metabo does not run hot; I usually run mine at 1200 RPM's or so. After all, it is a powerful electric motor encased in a very small housing; it is going to get a little warm.

audicoupej · 12-04-07, 08:50

My Hitachi can get hot, but I only have the PC to compare it to and that's not apples to apples.

Brad, thanks for the offer. I will take you up on it if I cannot get the Hitachi fixed.

Any thoughts on the Flex?

Jakerooni · 12-04-07, 08:52

Sounds like your brushes are clogging up. Take the machine apart and clean it all out.

audicoupej · 12-04-07, 08:56

Quote:

Originally Posted by Jakerooni

Sounds like your brushes are clogging up. Take the machine apart and clean it all out.

Thanks Jake, I plan on disassembling it later. I figured if it was the brushes that were bad it would just stop working.

Jakerooni · 12-04-07, 09:14

Quote:

Originally Posted by audicoupej

Thanks Jake, I plan on disassembling it later. I figured if it was the brushes that were bad it would just stop working.

eventually that will be the result but when they start clogging up and going bad they tend to do this. My Dewalt was doing the same thing for awhile. Took it apart cleaned all the copper brushes up and it's back to working like a champ.

audicoupej · 12-04-07, 09:48

Quote:

Originally Posted by Jakerooni

eventually that will be the result but when they start clogging up and going bad they tend to do this. My Dewalt was doing the same thing for awhile. Took it apart cleaned all the copper brushes up and it's back to working like a champ.

Good to know. I will play with it later today and let you know what happens. Thanks again.