I am new at running a Darex M4 or M5, I am doing something wrong and need help figuring out what?

[Kirk T]

I recently acquired an old Darex M4 or M5 drill bit sharpener. I have read a lot of post on this forum about how well people seem to get along with them, so I thought I should be able to also. But I am having trouble and need some pointers. I am not sure how to use the sliding indexing gauge to index the bit. I have tried many different scenarios and yet to produce positive results. I am assuming my problem is with indexing the bit in the chuck. I am using the 135-degree settings. I think splitting the point would help but the edge of the right wheel is rounded. Am I correct in thinking that a sharp bit without a split point should drill, ok? The picture of the drill bit shows arrows pointing to hot spots where the bit just spins on the metal and heats. I would like to put new CBN wheels on but want to make it sharpen a bit properly first. The only manual I found online to reference shows a different bit indexing jig. To those who have the old machines and successfully use them please offer pointers?

 

[metalmagpie]

Your drill indexing fixture is not their most recent model, but it works the same. Download the manual and read it. And don't worry about wheel corners or point splitting until you can get good grinds.

 

[Kirk T]

Your drill indexing fixture is not their most recent model, but it works the same. Download the manual and read it. And don't worry about wheel corners or point splitting until you can get good grinds.

Thank you. I had already downloaded the manual, read and printed it and put it in a binder to keep with the grinder. Problem I have is the manual doesn't tell you how to use the indexing setup it just says to use it. I am just assuming that indexing is my problem, but I am not sure. There is an adjustment for the height of the chuck holder it is all the way in the lowest position? The manual says nothing about that adjustment. The grinding wheels are worn down to 5 1/4'' dia. not sure if that is a problem? The manual doesn't seem to address the issue I am having. I plan to order CBN replacement wheels and try that. I was hoping an experienced user could give me some things to try.

 

[metalmagpie]

Thank you. I had already downloaded the manual, read and printed it and put it in a binder to keep with the grinder. Problem I have is the manual doesn't tell you how to use the indexing setup it just says to use it. I am just assuming that indexing is my problem, but I am not sure. There is an adjustment for the height of the chuck holder it is all the way in the lowest position? The manual says nothing about that adjustment. The grinding wheels are worn down to 5 1/4'' dia. not sure if that is a problem?

Adjustment for the height of the chuck holder? Are you talking about tightening the strap that holds the chuck during indexing?

I'm familiar with the M series grinder. Just a little puzzled by your terminology.

 

[Kirk T]

The drill bit chuck/collet holder can be raised about 1-1/4'' from the position it is in in the picture. The two pieces that make up this part is held together with two bolts that go through slotted holes. In the picture it is in the lowest position.

 

[metalmagpie]

Don't think that height adjustment is a problem as long as you're grinding on the front of the wheel.

The cam around the chuck can be radially adjusted. Procedure is in the manual.

 

[TGTool]

I have no experience with the Darex sharpeners so I'll start with that disclaimer.

The picture you have of the drill end shows the incorrect geometry. That is, the angle between the cutting lips and the chisel edge looks too small. That would imply that the flute orientation when setting in the chuck is wrong, or perhaps the cam setting as magpie points out is incorrect. If you can't find manual explanations for correct setting, you could at least experiment with fudging settings for an ad hoc correction.

 

[Joe Henderson]

It looks to me like you're set up for a split point.

 

[trevj]

My (limited) experience with a newer Darex than that was that you had drill bits that would drop in and work, and you had some, that just...wouldn't.
The ones that wouldn't grind well, you had to dick around a bit and pay attention to cause and effect, in order to put it in the holder correctly, that it ended up with the correct geometry on the tip.
Basicaly, you fudged the drill bit either a bit forward or backward rotation, while keeping it the same length in the chuck, then ground as if normal.