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Replace or repair a Makita 4.5" grinder

Lil'John

Former #278
Joined
May 20, 2020
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Title states it.

Longer, I killed the pinion and ring gears in the head of the grinder:
pinionGear.JPG
ringGear.JPG

Fucker attacked me so I destroyed it:lmao: Actually, 10+ years of heavy use finally caught up to it.

Anyone know of a good parts house for those two parts? Or is it going to be cheaper to get a new grinder?
 
I don't know if it's worth it but I've ordered parts from Makita usa before. I'd also look into a set of brushes.
 
Get another of the same make/brand/model and throw that one in your parts box of tools. Then when you burn up the armature on the new one and the gearbox is still good you swap parts around and make another grinder.
 
Last 3 (old) makita's I had die, called them and got nla (yea change one screw = nla!)
 
Google the part number for the grinder and "parts" and check out one of the parts dealers. I just looked at a handful of makita grinders on a site and that bevel gear wasn't available for many of them. If it's a metal gear, you're probably out of luck. If it's the plastic or composite one, they're only like $6.
 
I haven't checked prices in a few years but the last time I did mid grade 4.5 or 5 inch grinders in blue, yellow, green, or red were pretty cheap and far better than they were 10 years ago, I would not bother fixing a 4 inch. If you do though as already stated google your part number and Parts and E replacement and several other sites will pop up with schematics. If you want to push the envelope than google the part number you need, prices will vary quite a bit between vendors and you may even find it dirt cheap on Ebay. FWIW I am not a big fan of E Replacement and usually try to buy from someone else their lead times are slow and often they do not have the parts in stock.

Another FWIW I have grinders from 4.5 to 12 amps and find no real advantage over 7.5 and the bigger units are more cumbersome and tiring to one hand.
 

Tempting... not $200 tempting though:eek: I've actually considered getting a 5" to join the 4.5"s.

The "biggest" problem I've run into looking at replacements is ~$100 and many/most are only paddle switch. I hate paddle switches.

I was able to eventually find parts and they come in at $25. A bit better than $100 ;)

I actually like this 4.5". The right amount of power(7.5A) and size. I also like the Milwaukee that was being used as a dedicated wirewheel grinder.
 
I hate the on/off switch. Paddle is just easier for me to use with gloves or bare handed. I don’t know if I’d buy this for myself since I haven’t ever destroyed a grinder. I just know it’s used at the local community college and happy he professor hates the newest ones.
 
If it was a cord or brushes I'd say fix er up but those gears were either ruined by bad bushings / bearings or most likely took them out after. I'd say pick up a new whatever color 4.5" you fancy. I personally have beat the shit out of 2 10 amp paddle switch dewalts for years and just had to replace the cords recently.

I like the paddle because I run them without guards and some sacrifices have to be made to the safety gods. Last thing I need is a wire brush cup grabbing a loose wire and trussing me up like a pot roast cause I fumble fucked with the switch too long.
 
Are Metabo worth a shit any more? I know they got bought up by Hitachi a few years back and now they're selling them in big box stores has "Metabo HPT". Did they keep an original line of good stuff that's only sold by the welding stores and such?
 
Are Metabo worth a shit any more? I know they got bought up by Hitachi a few years back and now they\'re selling them in big box stores has "Metabo HPT". Did they keep an original line of good stuff that\'s only sold by the welding stores and such?
\n\n

Metabo has 2 lines - Metabo like this: https://www.amazon.com/Metabo-W9-115...91812054244-20
HPT like this https://www.amazon.com/Metabo-HPT-G1...91812054244-20

Big difference, however Hitachi tools werent that bad. I would put them on par with most of the big box brands and above Ryobi/lowes crapsman.

I'll never buy a makita grinder/tool again. First one I had let the magic smoke out after 5 minutes. When I called in for warranty they had a lawyer contact me back and interrogate me on how I was using it before they finally conceded to warranty it. Honestly ignoring the warranty would have been a better move on their part.
 
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I have one W7-115 and two W9-115. All seem to have less gear noise than my new Milwaukee. Power and weight is the same.
 
If it was a cord or brushes I'd say fix er up but those gears were either ruined by bad bushings / bearings or most likely took them out after. I'd say pick up a new whatever color 4.5" you fancy. I personally have beat the shit out of 2 10 amp paddle switch dewalts for years and just had to replace the cords recently.

I like the paddle because I run them without guards and some sacrifices have to be made to the safety gods. Last thing I need is a wire brush cup grabbing a loose wire and trussing me up like a pot roast cause I fumble fucked with the switch too long.

I just gave the armature gear and the "output" a pull and they are in fairly tight shape. So I think going the route of replacing the gears is right for me. I think what killed the gears is a couple of nasty shock load binds:homer:

My experience with a 4.5" paddle was not a good one. Too many issues with having to have hand in a certain position to activate the paddle and not being able to get in places I needed.
 
I just repaired the same angle grinder and parts a couple months ago. Ereplacementparts.com had every thing for like 25 bucks shipped
 
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