Mag Drill

[gimpyrobb]

Picked up a B&D 1551 mag drill today. Can't see a spindle speed on the tag, but it spins faster than I thought it would. Anyone have one of these that can give me some insight? ALso it has a 3/4 inch chuck. Anyway to use annular cutters with a chuck, or do I have to by something different to use them? I got home late and can't find my camera, will post pics tomorrow.

 

[quarkz]

I know some of the higher priced miliwauki's at the lab had an adjustable feed rate.
Same drill motor as the big 1/2 corded drills.
On the grip next to the trigger there was a thumb wheel that would set max speed the trigger would pull to.

The Evolution Bora 2800 that I just picked up has a set speed.
It uses 3/4 annular and also came with a 1/2" chuck .
Mine spun faster than I would have thought also.
But I countered by adjusting how hard I made it plunge into the metal.
I was taught to get the metal to come off of the cutting tool in long continuous spirals byt adjusting either feed or speed.

Worked great re-drilling the holes on the side of the frame rail, needed to hook the rear pintle brace back up.
The only chatter I got was when the bit share the space from a previous hole.
For that I just went to a smaller bit that fit into the metal remaining, then enlarged that hole with the proper sized bit.
Just use lots of cutting fluid and the safety chain is any other orientation than sitting on a horizontal surface.

On mine the annular bits are held in by 2 hex head set screws, 90 degrees offset.
I can remove the extension that holds the annular bits by loosening an internal socket head set screw. Then my half inch chuck threaded into that hole.

This decreases the travel of the drill, so I have to use full length bits, no jobbers.

Not a bad gadget for $ 400 from buyweld.com
http://www.buyweld.com/bora2800.html
shipping took under a week.

 

[gimpyrobb]

Mine is an older unit, don't think it has a speed controll. I will have to look at it closer tomorrow. I can just get a router speed controller to slow it down.

 

[m16ty]

I've got a Milwaukee and it has adjustable speed. Don't know anything about the B&D. You can't beat a mag drill for drilling frames and such.

 

[LanceRobson]

I've seen them with both chucks for round and hex bit shanks and set up for bits with Morse taper shanks. The mose taper ones were used for both drilling and reaming holes to bigger diameter and always seemed to be slooooow in comparison to the drills with chucks. Maybe the ones with chucks were intended for smaller holes due to the higher RPMs?

Do you know anybody with non-contact tachometer (the kind that reads the RPM with a laser or other light beam reflecting off the turning shaft) They sell for $25 or so (on epay) for cheap ones and at least you could work out the largest safe bit diameter from the RPMs.

Lance

 

[Jones]

Not sure about B&D but my Milwaukee's Jacobs chuck comes off and a supported extension goes on in it's place. The 3/4" Weldon shank annular cutters (Rotobits) attach to that extension.
There are 1" depth and 2" depth cutters so the spacer place has to be positioned either over or under the extension support for full travel.

Since the annular cutters are flat-faced and cut on the end you can staighten holes or realign by drilling "half holes" without them trying to veer into the existing hole.

Things to remember with a mag drill:
1. The thicker the metal, the better the magnet likes it. Sandwich the work piece between a second piece of plate on the opposite side and the magnet when drilling thin stuff (1/4" or less).
2. Always wipe off any chips before attaching the magnet to the work piece; the magnet must be in full contact to hold securely.
3. When drilling upside down or on the side, always use a safety strap. You can exert enough down force to dislodge the magnet so let the drill do it's work. No need to force it.
4. A good cutting oil will help clear chips, make the cutters last longer and will aid the drill in spitting out the plug the annular cutter creates when you finish the hole.
5. When drilling through two layers, you'll have to stop and clear the plug from the first layer before continuing on. If necessary to remove the drill to do this, picking the position back up is easy; just extend the cutter, get it nosed into the hole and then turn on the magnet.

ALWAYS!!! ALWAYS!!! Remember to turn off the drill before turning off the magnet.
If you don't, a broken cutter or bent twist drill will be the least of your worries with a mag drill running in your lap.

 

[wildbilly1760]

"The 3/4" Weldon shank annular cutters (Rotobits) attach to that "
as Jones said.

I would look into getting that type of attachment. I have used these annular cutters for drilling, and they are the way to go. The mag drill is the only way to go when doing frame modifications. I never did any military vehicles....yet.... but where I used to work we stretched and shortenned frames for dump trucks quite a bit. Fastenal is where we bought our cutters and also several different mag drills over the years. We alsways ran them full speed, and kept squirting them with a shot of cutting fluid (water oil out of the bandsaw). Looks like milk. Keep the bit wet and dont push too hard and you can get hundreds of holes with 1 cutter. And they stay centered, with a centering pin. I think they cost about 35$ for a 13/16" annualr cutter.

Bill

 

[wldrbob]

same thing with my dewalt remove chuck put in extension and att annular cutter and belive it or not brakeclean is a great lube for drilling holes