5/8 Inch Keyless Drill Chuck

[Matanuska]

Does anyone have one of the 5/8 Inch Keyless Drill Chucks? If so, does it grip large bits more firmly than the keyed chuck? I’ve had problems with my large diameter hole cutter slipping in the keyed chuck despite my best efforts to tighten it.

Also, is the keyless chuck able to grip smaller bits despite its larger max bit size? How do you like it overall?

[chapmanruss]

I do have one of the Shopsmith 5/8" Keyless Chucks but haven't used it much. In fact, I haven't found it yet since moving nearly two years ago now. It is in a box somewhere in the Shop with 2 of my Miters and other parts I haven't seen. Wow, time flies. I need to find that stuff. With so much to do here at the new home and a lot more property, I haven't had as much time to work on Shopsmith stuff. I haven't finished a restoration in 2 years and have several to do.

Since I have several of the 1/2" Drill Chucks made for the Shopsmith over the years I still tend to use them. The 5/8" Keyless Chuck is much bigger and heavier than the 1/2" Chuck. I bought it when it was on sale for drilling jobs needing a larger than 1/2" capacity Chuck. Very few of my Drill Bits have a shank larger than 1/2".

Something to consider for anyone using the Mortise Attachment for their Shopsmith Mark or Model 10 tool is the 5/8" Chuck is too large to use with it.

[BuckeyeDennis]

Are you talking about something like this General 55 Circle Cutter?

Hole cutter.jpg (59.53 KiB) Viewed 22703 times

I have one of those, and it didn't work well out of the box. I finally realized that the cutter had no relief angle ground on it, so it would rub and burn while cutting, which undoubtedly required excessive torque. So I reground the cutter to add relief and a sharp edge, and after that it worked well.

I will say, however, that I wouldn't use it chucked directly to a conventional headstock,as they just don't have a low enough speed IMO. The General Tools product page says "Only safe to use with drill press running at less than 500 rpm". And that still seems awfully fast if the cutter is extended more than halfway. When I use mine, I always use it with my SS Speed Reducer.

I also use one of my Jacobs 3326 chucks, each of which was acquired along with a 10E or a 10ER. They seem to be a more precise, robust chuck than the later ones from Shopsmith, and they can handle my circle cutter without issue.

[Matanuska]

Something to consider for anyone using the Mortise Attachment for their Shopsmith Mark or Model 10 tool is the 5/8" Chuck is too large to use with it.

Thanks - will keep that in mind.

[Matanuska]

Are you talking about something like this General 55 Circle Cutter?

Yes - that’s exactly the one I’ve got. I’m running it on a PowerPro headstock so getting the low rpm isn’t a problem. Mine doesn’t burn when it cuts and it seems pretty sharp. It just binds and slips occasionally. What does your cutter look like now that you’ve added a relief angle?

[BuckeyeDennis]

As you can see from the first photo, I had also had some problems with mine slipping in the chuck, all before I ground relief angles on the bit, IIRC.

Cutter_1.JPG (85.46 KiB) Viewed 22511 times

The idea is to grind back the non-cutting flanks of the bit at an angle, so that only the cutting edges contacts the workpiece. I also reverse-tapered it a little from the tip back up to the shank, as all the cutting should happen near the tip. Any contact higher up is just rubbing.

Cutter_2.JPG (73.24 KiB) Viewed 22511 times

I ground it freehand on a belt sander, so it's not the prettiest, but now the bit cuts free and clean. In hindsight, I probably didn't need to grind the front face of the bit -- leaving it flat should be fine.

Cutter_3.JPG (88.33 KiB) Viewed 22511 times

[Matanuska]

I will be grinding with my SS belt sander as well so good to know. Will try a single grind first. Based on your input I think that should do the trick. Thanks!

[BuckeyeDennis]

If you do only a single grind, it should probably be on the inside face of the cutter. Otherwise the inside cutting arc, which is defined by the radius from the spindle axis to the front cutting edge of the bit, passes right through the inside face of the cutter. Just imagine making a top-view drawing of that arc with a compass, with the cross section of the square cutter exaggerated. That pretty much guarantees heavy rubbing on the ID of the cut.

I just remembered that I have some pictures of the cutter in use after I ground the bit, making a combination VFD mount and frame stiffener from Baltic Birch plywood for a 3-phase dust collector. I first cut from one side of the workpiece until the pilot bit broke through ... taking great care not to cut a big hole in my 520 table!

Cutter_4.JPG (178.5 KiB) Viewed 22443 times

Then I flipped the workpiece over, realigned it by inserting the pilot bit into the hole, and reclamped it to the table. This time I fed the quill just until the center was cut free.

Cutter_5.JPG (125.09 KiB) Viewed 22443 times

Here's the finished panel. The cut was very clean on the hole ID, with zero burning or tearout.

Cutter_6.JPG (119.66 KiB) Viewed 22443 times

[JPG]

Oh I think under cutting behind ALL cutting edges is best.

The front face is not radial to the center.(it leads a radius)

[RFGuy]

I own the Shopsmith keyless drill chuck and love it. I am just a hobbyist and much prefer a high quality keyless drill chuck to a keyed one. I even bought a Rohm keyless chuck to swap out on my Milwaukee cordless drill because I preferred the feel of the Rohm keyless chuck to the stock chuck from Milwaukee. Perhaps if I was a machinist I would prefer a keyed chuck instead? I can't answer your questions on using it with larger than 1/2" bits because I haven't tried this yet and I don't remember the smallest bit it can firmly grip. I have never liked those large circle cutters. I am sure if the workpiece is clamped securely and if the cutter is super sharp it would work flawlessly. For large diameter holes like this I much prefer a rotary tool. RotoZip made them popular, but most power tool manufacturers sell a version of these nowadays. Mine is from DeWalt...I have used it often and love it. These cut through plywood and drywall like they are butter. Just thought I would suggest it as an alternative here. Having a rotary cutout tool can be very handy around the house for DIY, etc.