Magnetic Drill vs Regular drill for Bobbing

[Awesome Possum]

After 2 months of fire bans I finally got 'round to torching the rivets on one side of the deuce, sort of my "NO GOING BACK!" point. Woo hoo! In researching the process, I came upon mention of the magnetic drill. I thought I had nearly every generalized power tool but, this was a new one to me.

I'd really been dreading the drilling of the shackle holes. I found a pic on XM381 of this drill and thought "That's the ticket!" But before I go rent one I wanted to get some thoughts on the magnetic drill, how hard is it to use, what kind of bits to use, voltage required, just anything I need to know about it. I searched for something specific on this and did not find anything.

I live in the Killeen/FT Hood, TX area and wondered if there's anyone in the area who'd be willing to rent me such a beast (with suitable deposit), or maybe even help with the drilling of these holes a few weeks down the road.

 

[ryker725]

I see them used at work a lot for drilling out galvanized structural supports. They are typically pretty heavy due to the electro magnet. You should be able to find an equipment rental place that should have one.

 

[Marcel]

I bought one several years ago to drill holes into my backhoe. Just think of it as a mobile drill press. It requires 110v current and is great for drilling steel I beams as well as any steel plating that you can attach it to. You can also drill & ream holes, tap holes and remove rivets. Mine has a variable magnetic rheostat. It is quite heavy though and moving it around will wear you out after a while. I have a half inch chuck on mine so I can go up tio 1/2 in drills but I can also use hole saws for larger holes. As with all drill presses you should let the drill bits do the work so don't try to muscle it down to cut your holes and use center drilld to line up and start all holes. It is a specialized tool but an invaluable tool when the need arises.

 

[gimpyrobb]

Marcel pretty much summed it up. Some of them use annular cutters rather than drill bits, but the annular cutters are $$.

 

[TheWeatherMan]

I have used one at a railroad museum I volunteer at. They work really well but can be hard to position till you get the hang of it. Also with some metals go slow cause these drills have the tendency to snap bits

 

[topo]

These drills are nice to use on drilling frames . lots or torque be sure to set up a safety strap or chain in case it falls .

 

[skinnedknuckles]

I used a portable Jancy Slugger mag drill with rota-broach bits when I bobbed my deuce. The same one that I use in my big truck shop for drilling truck frames. Just put it on the frame, line up the center pin with your center punch mark for your hole, flip the mag switch on, then switch the motor on and drill ,adding cutting fluid as you go. No need to use your body to push the drill through just turn the handle. Works on flat horizontal, vertical, up-side down surfaces. Years ago Snap-on offered a sort-of portable drill press shaped like a c-clamp and used an air drill , I bought one and it works great for smaller jobs. It would be quite a bit of work to have to physically push an air or electric drill through a thick frame a bunch of times. Mag drills are pricey if you were to buy one but if you can rent it ,it would be money well spent

Paul in Janesville, Wis.

 

[G-Force]

A cheaper and easier way would be to start small (1/8" pilot hole) and work up until your hole is big enough to knock the head off of the rivet easily with a hammer and chisel.
Also, invest in a Drill Doctor as you will be dulling alot of drill bits.

 

[wreckerman893]

I use a thin cutting disc in my big angle grinder to cut the heads off the rivets and then punch them out with a BFH.

As far as drilling new holes if you don't have a magnetic drill or don't want to rent one you can drill a small pilot hole and then use the correct size drill bit to cut the hole with.

 

[quarkz]

I am not saying it can't be done as stated in the last two way.

But , the annular cutter/ plug cutter bits will put the pilot hole /step drill process to shame.
The annular bits lust cut away the perimeter of the hole where a set of regular drill bit have to remove the entire area of the hole. Also the mag-base keeps things square, where a hand held drill tends to wobble. Lastly the amount of cutting edge on an annular is the edge of the tooth multiplied by 30-ish teeth, on a drill bit it is the a little more cutting edge, if it is held straight, but only multiplied by 2. This really leads to ease of drilling holes.

All the work is in the set up.

Also for drilling holes where gravity is working against you, use the supplied chain and clip to keep your mag-base from rapidly disassembling when it meets the floor.

There are some low budget ones out there if you are buying and not renting.

 

[cjtroutt]

Rotobroch makes cutters to use in a drill cordless 1/2 in drive they alot cheaper for the kit mag drill I used them on the road but when home mag drill works for me.
Look up rotobroch on google.
also here is a photo of them keep them clean and use cutting fluid / oil as tool cool and you will never go back to drill bits for basic drill hole or frame bolting needs.​

 

[mikew]

The first 3/4 drill bit you snap in two when you're trying to drilling the bumperette holes by hand will most likely pay for a days mag drill rental.

And when you flip the drill up-side-down in it's mount (so it's like a drill press that goes "up" instead of "down") to drill the various holes in the bottom of the frame, instead of laying on the ground, pushing a hand drill up and getting hot metal shavings all over your face.... well lets just say you'll want to own one!

 

[m16ty]

I've removed several sets of rivets and I use a torch. It's much faster than drilling. You have to be very careful not to cut into the base metal though. I first cut the head off and then blow a hole through the middle of the rivet. The hole in the middle seems to loosen it up in the hole and it will drive out pretty easy.

 

[jatonka]

Hougen has a mag drill for $800 that is great for doing deuce frames, I got one and now I can really drill holes fast and not dread it. JT

 

[Tinwoodsman]

When I drilled the new frame holes on my bobber, I tried everything from conventional drill bits of various sizes. This worked fine for 3/8 to 1/2" holes but anything larger just wore me out, particularly when the bit grabbed and spun the drill around nearly breaking my hand. I finally drilled the 5/8 and 3/4" holes by starting a smaller pilot hole and then using a step drill bit. This went fast and easy. Due to the thickness of the from I did drill from both sides because the step bits have shallow depth. It was unbelievably easy to do it this way.

 

[Marcel]

I have an issue with some of these methods and that is that there is a potential to cut into the frame making an oblong hole. If you can't get the mag-drill exactly on center you can cut into the frame easily without knowing it. Here would be my method.
1. Set up mag drill as close to center of rivit as possible.
2. Drill starter hole with center drill.
3. Drill through hole with 1/4 inch bit.
4. Machine rivit with a two flute, flat bottom, single end, center cutting end mill till you reach frame rail.
5. Punch out remaining rivit with hammer & punch
6. Use plenty of cool tool.

You can safetly remove any rivit in this manner without affecting the frame rail.

 

[Floridianson]

I bobed a Deuce with out a mag. drill and did not have problems just tireing.
Not that it madders in this form but you won't hand drill and 5 ton frame.
I did buy a mag drill and will use it for any truck now and use annular on the 5 ton and regular bits on the Deuce.
I did use the torches on all my rivets on the Deuce and some on the 5 ton.
I found it's best to drill out some rivets like the ones where there is double frame on the 5 ton and on the Deuce the ones that hold the back plate/pindel on. There the rivet have expanded inbetween the two peices of frame and if you torch them off you just made more work for your self as you will be drilling them out. Now this is for the people who care about the condition of the frame and don't just blow holes in the frame with a torch and fill the hole with bolt and washers. WTB's

 

[DUECE-COUPE]

you are only gona need it for the 12 holes on the side. i used a heavy duty drill and a floor jack to do the bottom holes. i ran the floor jack and my brother in law ran the drill. for the sides, i used a couple of new sharp bits and a big guy (brother in law) to push the drill. i also use a 1/4 pilot hole first to get it all lined up.

 

[Awesome Possum]

Keep your comments coming! I'm finding them all helpful.

 

[blackrock]

If your doing a stock Bob (and doing this once) i would start with a 1/4 drill bit, the use a stepper drill up to 9/16 and run a nice 9/16 bit threw it (info based on using 1/2 hardware). Now, if your doing a lift kit and or plan on bobbing alot of trucks i would then think about buying/renting a magnetic drill. Cause with my lift you have to drill a total of 40 holes in the back and 20 holes in the front. Kyle