Darex M5 questions/problems

I just bought a used darex off ebay.

Seller said machine was M5 and it looks like M5, but there is no model number on the machine. I figure this means it started out as something else and someone added the accessories to make it into an M5. According to the manual I downloaded from darex, the M5 has CBN wheels on both sides. This one has a AO wheel on the right. It appears that a special hub is required to mount the CBN wheels ?

When first switched on, the motor growls as its coming up to speed. It sounds ok after that. Is this an indication that something is wrong with the motor? Perhaps the bearings are going out ?

There are deep grooves in the swing fixture where the chuck collet pins ride. Is this normal? It seems to me that the grooves will alter the grinding profile. This fixture also has a copper insert in this area. Was this insert added as a repair?

I did a test grind on a 3/8 bit. The chisel point is way out of wack. In order to make the point right, I had to mount the drill in the collet chuck with the relieve set to 138 even I was grinding a 118 bit.

In general the Darex looks like a cheaply made machine. All the castings are white metal and they have adjustment screws that push directly on the metal. There is a large divit under the feed screw on the casting. The swing castins is real sloppy too.

Is this a normal machine or a lemon? thanks chuck

Reply to
Chuck Sherwood
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I have an M2, early version of M5. Sounds like we have same unit. Mine is a LOVELY grinder after TLC to get everything adjusted. Sounds like your needs more TLC than mine did. Darex has a great manual for the machine, download that and read about all the adjustments (I have an original I could send if you need). In particular there's pins on the collet that will take care of the drill grinding off center. This must be set very carefully. At the same time there's pins to make the collet just turn without slop in the fixture.

I'd find someway to fill those wear grooves. If you're just doing a hobby quantities, some sort of bondo would do it. I wouldn't worry about the motor till you got the other stuff done. You may need to install new bearing from what you're saying.

Reply to
Karl Townsend

Early M5s came with AlOx wheels, later (much more expensive) ones came with CBN wheels. You got an early one with some wear.

I personally don't worry about a little growl on startup if the parts grind true. I sold a Baldor recently to a buyer who didn't like the startup growl and tore it all apart and replaced the bearings. Whatever you like -- to me, don't fix it until it's broke, and it's broke when you can't get good grinds out of it.

It's an M5 if it has the point splitting/web thinning attachment on the right side, else it's an M4.

*Some* grooving is normal. The manual can be downloaded from:
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Darex has discontinued these grinders, ending about a 20 year production run. My personal guess is that this was a marketing decision and not a technical one -- i.e. they feel they have saturated their market with M5s and they now want to try to obsolete them so they can sell to the same segment all over again.

If your chuck holder part is totally worn out you can replace just that casting, or you can buy entire M2 setups off ebay cheap and they will bolt right on. Mine has a copper insert, yes, and came new with it. Yes, the castings aren't machined cast iron, but if the machine is kept reasonably clean then they last a real long time. Darex still supports this machine for some parts but normally it's the chucks that go bad, not anything else.

If you paid less than $400 you still got an OK deal. If you paid $500 or more then you paid for one in excellent condition and didn't get it, and you may be able to negotiate with the seller for a partial refund by threatening negative feedback.

Grant Erw> I just bought a used darex off ebay.

Reply to
Grant Erwin

I have used this machine much and I like it. I have made comments below.

The first M5 I used had AO wheels. The next had the diamond wheels. I believe an M5 is an M3 with the addition of the split point/web thin attachment.

Not sure about this.

IIRC the manual mentions this is normal. If someone tried to repair it, I would be concerned how accurate the repair might be. It seems to me that the only affect would be that the drill is closer to the wheel. It would be like turning the infeed knob toward the wheel a little.

I've seen people putting all their weight into the machine while grinding drills. I've never liked that. Now where I work there is a black diamond drill grinder. The same thing happens.

If more than about .040" is ground off the drill it needs to be re-located in the setting fixture. Also make sure the drill point touches the black dot in the setting fixture. The smaller the drill, the less can be ground off before needing to be relocated. Also I have experienced drills sliding back in the collet. I was never able to solve this problem.

The machine might not be the best available and is not the most expensive either. I think the castings are a special material that has copper in it. I would not be concerned about the divit. There is an adjustment that can be made to solve the sloppy swing casting.

Maybe the machine has been used hard and needs a little fixing. How much did you buy it for? MikeH

Reply to
Mike H

It was an ebay auction and I'm embarrased to say the closing price. I bid high because I had numerous discussions with the seller and it seemed like he put a lot of work into fixing up machines before the sale so that he doesn't have returns. I need to get some reference points in order to decide what to do. Right now, I am in favor of returning the machine.

I also bought an OLD black diamond machine from this guy and it seems like a very nice machine. I bought it because it can do the small drills. The darex can do bigger drills and special profiles for brass and flat bottom etc.


Reply to
Chuck Sherwood

Reply to
Robert Swinney

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