Magnetic Drill vs Regular drill for Bobbing

[landfillman]

I have a truck frame drill from Waber. I got mine from a scrap dealer that had no idea what it was. You mount a 5/8ths drill motor Milwaulkee/ Porter Cable on it. It works for horizontal holes. Its basically a stand with an acme screw that raises a roller mounted stand that holds a drill press quill. The motor mouns on it and the quill housing has a set of stay chians that you anchor it to the frame with. What I usually do when making new shakle mounts when moving truck axles I use the bracket as a template and use a drill guild bushing or annular cutter.


Its a handy tool about 3500 new but I got this one for 25 bucks minus the motor. I found a dead mag drill at a salvage shop for 100.


THis is a company pic of mine. I have mine in the shop being refurbished right now.
Home of the Frame Drill for Chassis Drilling

 

[oddshot]

"buy real cutting oil and use drops of it. Don't buy this oil-water mixture used in professional lathes. That works good if you have a constant flow of the stuff onto the drilling area, using gallons of the stuff during the day. For a one-time job by non-professionals without the fixed permanent flow, real cutting oil works better".

+1
Cuttin' oil and sharp drill bits are your friend!



I did the whole job on my truck by hand using cutting oil and an old Milwaukee aluminum case 1/2" drill ... probably 20 years old than I am. Max rpm? 560.

With a good sharp bit and a couple drops of cutting oil that old drill just curls off ribbons of steel.

You can get good cutting/threading oil over at the Home Depot in the plumbing department ...

Oatey Dark Thread Cutting Oil ... its runs about $11.00 a quart.

"A little dab will do ya'!"

oddshot

 

[goldwing2000]

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.​

+1!! I love my Rotabroach set!! They just eat right through anything up to 1/2" thick. Anything over 1/2", you just have to cut the rest from the back side.

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.

Except that the OP is not talking about drilling rivets. He already torched them off. The discussion is about drilling the new holes for the spring brackets.

 

[Marcel]

+1!! I love my Rotabroach set!! They just eat right through anything up to 1/2" thick. Anything over 1/2", you just have to cut the rest from the back side.




Except that the OP is not talking about drilling rivets. He already torched them off. The discussion is about drilling the new holes for the spring brackets.

Ohhhhh. That's much easier. Yeah, now these techniques make sense.

 

[joshuaz223]

i too have the milwaukee mag drill and find it an extremly usefull tool. a few things to remember when using them though is to always safety chain it up when not flat drilling. magnets like thick metal. the drill won't hold well on thin steel, so clamp a piece of heavy steel on and attach the magnet to that. broaches are nice in a production enviornment but are expensive to purchase and sharpen compaired to a standard drill bit. use the shortest cord possible. between the magnet and the drill they draw a lot of current and when sucking through a small/long cord you can have problems. if you live near me and need to borrow it your welcome to any time. i have a good assortment of bits up to 2".

 

[quickfarms]

the only way to drill a frame

 

[Trango]

Late to the party so it seems as though this advice has already been given, but after 15 years of metalworking, I finally bought a mag drill.

I think back to all of the time I wasted with holesaws and step drilling.

Bottom line - a mag drill, for metal 1/4" and over, is the. way. to. go. No ifs ands or buts. It cost me about $800 to get set up with the machine and enough bits to get started - it was money very well spent.

Pair it with a complete set of transfer punches to transfer over bolt patterns etc, and a mag drill is unbelievably useful.

Hope this helps,
Bob

 

[Awesome Possum]

Except that the OP is not talking about drilling rivets. He already torched them off. The discussion is about drilling the new holes for the spring brackets. [/QUOTE]

Yes, that was the original question, but since it's been brought up, I'm having a helluva time getting any rivet to budge with an air chisel. I've thought of heating up the mounting plate, but this really does nothing for expanding the frame itself. Now I'm thinking of renting a mag drill just for drilling out the rivets, then giving a go at getting a chisel between the frame and the mounting plate.

The concept of bobbing a deuce is simple, but the execution is a bear!

 

[jamesfrom180]

have you tried drilling the shank of the rivet?

I have never done this but I have had people tell me to stick a welding rod on broken bolts to heat and loosen them. Take a 6010 and turn the amperage way down and just pump the juice to it for 3-5 seconds. I was told to just unclamp from the rod to break the circuit. The old guy said that is why he kept all the shorties.

Again never tried and suspect on a smallish buzz box it might not be that good.

 

[goldwing2000]

Yes, that was the original question, but since it's been brought up, I'm having a helluva time getting any rivet to budge with an air chisel. I've thought of heating up the mounting plate, but this really does nothing for expanding the frame itself. Now I'm thinking of renting a mag drill just for drilling out the rivets, then giving a go at getting a chisel between the frame and the mounting plate.

The concept of bobbing a deuce is simple, but the execution is a bear!

If you don't have a flame axe, I've found an angle grinder is the next best thing. It will make short work of rivet heads, you just have to be careful to not cut into your brackets. After the head is off, some others on this thread have had some good ideas about center-drilling to relieve pressure. I've found a flat punch on an air hammer works pretty good (but I haven't messed with a Deuce frame yet. This is all light truck experience talking) I'll be bobbing the Organ Donor shortly, so we'll see how well the techniques transfer to bigger things!

 

[goldwing2000]

have you tried drilling the shank of the rivet?

I have never done this but I have had people tell me to stick a welding rod on broken bolts to heat and loosen them. Take a 6010 and turn the amperage way down and just pump the juice to it for 3-5 seconds. I was told to just unclamp from the rod to break the circuit. The old guy said that is why he kept all the shorties.

Again never tried and suspect on a smallish buzz box it might not be that good.

Except that if you heat the rivet shank, you'll make it larger and thereby even harder to get out. If anything, you'd need to heat the metal around the rivet or find a way to freeze the rivet.

 

[jamesfrom180]

That is the logic I put to the mechanic when he told me about this method to remove bolts. Now a rivit is by nature expanded not really rusted in to place but seeing how easily the bolt came out after he did this I was sold. Matter of fact it was just a set of vice grips on the end of the welding rod. Now this bolt had previously been torqued off and it came out like butter. From working with black smithing I will say iron will relax. All I can say is try it

 

[goldwing2000]

That is the logic I put to the mechanic when he told me about this method to remove bolts. Now a rivit is by nature expanded not really rusted in to place but seeing how easily the bolt came out after he did this I was sold. Matter of fact it was just a set of vice grips on the end of the welding rod. Now this bolt had previously been torqued off and it came out like butter. From working with black smithing I will say iron will relax. All I can say is try it

Have you done it with rivets or is it still theory?

 

[Nonotagain]

Except that if you heat the rivet shank, you'll make it larger and thereby even harder to get out. If anything, you'd need to heat the metal around the rivet or find a way to freeze the rivet.

A rivet by nature work hardens when squeezed or bucked.

Heating the rivet will remove the temper, making it softer and allowing the removal by force.

I'm not advocating heating the frame to the point of being red, but the mentioned method of hitting the rivet with a weld rod will work to soften it.

In aerospace we use a lot of exotic metal rivets. The bi-metal rivet made of Columbium/Titanium is frequently used on parts with tight fitting holes that are reamed to size. The Columbium is the rivet tail and has to be deformed in one or two squeeze/buck operations or you get to drill it out and reinstall. The titanium shank does not deform during installation which is the reason for using this metal combo.

I have a couple of 8X and one 12X rivet guns left over from when we built some large bomber stabilizers. That area was one place you didn't want to work with a hangover.

 

[Jump Start]

Thanks for the tip, when my son gets home form afghanistan he is wanting to bob a truck so we will give this a try.

Did you hear about the lady that they arested getting on a plane with some crochet needels? They thought she was going to make an afgan.

Jesus Loves YOU

 

[Awesome Possum]

If you don't have a flame axe, I've found an angle grinder is the next best thing. It will make short work of rivet heads, you just have to be careful to not cut into your brackets. After the head is off, some others on this thread have had some good ideas about center-drilling to relieve pressure. I've found a flat punch on an air hammer works pretty good (but I haven't messed with a Deuce frame yet. This is all light truck experience talking) I'll be bobbing the Organ Donor shortly, so we'll see how well the techniques transfer to bigger things!

This sounds kind of ominous. In flattening the rivets against the bracket, yes, I've ground into the bracket as well. Should I expect something bad from this, and what is the cure?

 

[mikew]

To remove rivets I've ground, air chiseled, drilled and used a cutting torch to get them out.

Cutting torch to blow the heads off and a little bit of the center and then an air chisel with punch in it to push them out is by far the easiest.

The hard part with the other options is that you really can't get to the bottom bogie rivets. A cutting torch or air chisel is about the only way.

If you don't have a cutting torch the next easiest way I've found to remove the side rivets is drilling (you still have a problem with the bottom rivets). The rivet shank is 7/16" and you don't need to drill them completely out, just 5/16" or so, then a hammer and punch.

I made a tool to center the drill on the rivet head. I used a lathe but you could just take a piece of steel, drill a hole 5/16" all the way through then a shallow hole the same diameter as the rivet head (can't remember what size the heads are). Push the tool on the rivet head then run the drill down the center.

Now, I love my mag drill! I used it today to mount a receiver hitch. Using it to drill upside-down is one of it best uses. I put a transmission adapter on my floor jack, mount the drill base and then flip the drill motor.

 

[jamesfrom180]

I love the production jig.
No I have never tried the welding rod with rivits. We did relax the rivits with a torch. Cut the heads then use a really large hammer or air hamer. But this was on a 1952 chevy.

 

[goldwing2000]

A rivet by nature work hardens when squeezed or bucked.

Heating the rivet will remove the temper, making it softer and allowing the removal by force.

I'm not advocating heating the frame to the point of being red, but the mentioned method of hitting the rivet with a weld rod will work to soften it.

Good information. Thanks!

This sounds kind of ominous. In flattening the rivets against the bracket, yes, I've ground into the bracket as well. Should I expect something bad from this, and what is the cure?

Well, if you're talking about your bogie brackets and you don't plan on reusing them for anything, then no big deal. But if you're talking about your new spring brackets and you grind a groove into it or grind it flat but at an angle, then it compromises the clamping force of the bolt. Technically, it should be welded up to fill the gap or make it level and then machined smooth and flat.

 

[Jones]

From personal experience in the shop and at home with the baby HEMTT, here are some tricks I've found work every time:

Mag drills like to be attached to thick metal. If you're drilling 1/4" or thinner, back up the piece with a 1/2" thick piece of plate (no need to weld in place, just so the magnetic field can grab it). The magnet holds better if it thinks it's against a thick surface.
The mag base has to be against a clean, flat surface. If there are chips in the way, or if it's curved or only partially covered by the base, the magnetic field (grip) won't be as strong.
ALWAYS use a safety strap or chain when drilling from the side or bottom. If the mag drill comes off, it won't stop running until you recapture it and hit the off button (hard to stay calm and composed, especially if it's running in your lap).
A mag drill has enough torque to break as big a bit as it's capable of turning so cost is another reason for working safely.
"It'll be OK, I'm only drilling one hole" is quite often heard just prior to a trip to the emergency room. One hole or twenty, work safe!

Annular cutters are good for big holes because they cut like a hole saw with lower chip load that a twist drill. If you're drilling a new hole just mark with a center punch. The annular cutters have a center pin that makes lining up on your mark a snap. That pin becomes spring-loaded thanks to the mag drill design and serves to eject the "button" out of the cutter once the hole is through.
The only flaw of an annular cutter might be the inablilty to drill "blind holes" since it leaves the center undrilled.
Annular cutters are also able to drill off-center of an existing hole because, unlike a twist drill, they don't have a beveled point that keeps trying to find it's way into an existing hole. Say you have an off center 1/2" hole that needs to be enlarged to 5/8" and be put back on center; an annular cutter is the tool for the job. All they ask is good cutting oil and chip removal, especially in the case of deep hole drilling.
My trick for chip removal (works good on twist drills too) is to apply down pressure for cutting 3 to 5 seconds, then back off just enough to weaken the chip so it breaks off and falls out of the way, then start down feed again. This is also good for your knuckles as you won't keep getting whipped by that 8" long spiral chip every time it goes around.

Rivet removal is a snap with a couple of tricks I've learned.
If you're good with an angle grinder; a .040" cut off wheel in a 4" grinder makes short work of rivet heads. A little more work is a sharp cold chisel and a 4 pound sledge (don't waste your time and energy with a little general purpose ball peen hammer).
Once you've got the rivet head off, make a center punch mark dead center on the rivet shank and drill an 1/8" starter hole deep enough to be into the shank the thickness of the frame rail or bracket but not so deep that you drill through the rivet head on the other side. Now step drill up an 1/8" at a time to within 1/16" of your rivet shank diameter, always drilling to the bottom of the hole, not all the way through.
Step drilling this way gives you light chip load (1/16" per side) and lets you have plenty of control in keeping the hole straight and centered. Stopping 1/16" undersized (7/16" hole into 1/2" rivet shank for example) lessens the chance of drilling into frame, bracket, etc.
What you've done by drilling out the rivet is to weaken it's internal structure. The remaining thin walled shank "tube" will collapse easily. Last, slip a pin punch into the hole 'til it bottoms out on the underside of the remaining rivet head and drive it out with a hammer. What you couldn't move with an air hammer before will almost fall out now that it has no internal support for it's shank-to-hole grip.

True, this is more time-consuming than the torch, or sledge hammer and big punch method; but once you start using it you'll find you really have to work hard to ever screw up a frame or bracket hole again.