Drilling 9/16 holes in A36

[Monza Harry]

Sharpen the drill flatter to help with the "pull through" and if your DP has a spindle/quill, lock set it to dampen the vibration and fight the "pull through". Also as stated above ditch the intermediate drill [3/8" Dia.] Then as to coolant I prefer to use a cutting oil, but you have restrictions so use tap water or compressed air to help lower temps/extend tool life. Harry

 

[metaleltr]

This would be an ideal job for a rotabroach.

 

[welder4956]

This would be an ideal job for a rotabroach.

Yes, with a pilot.

Also, if the drill press is having trouble with these holes it may be time to step up to a better drill press.

 

[bri_man57]

Yes, with a pilot.



Also, if the drill press is having trouble with these holes it may be time to step up to a better drill press.

My rotabroach set only needs a center punch mark, not a pilot. I use a lubricant on my rotabroach though, wouldn't want to mess those up

Sent from my SM-N920T using Tapatalk

 

[mcbane]

Yes, with a pilot.

Also, if the drill press is having trouble with these holes it may be time to step up to a better drill press.

I agree. Seems like everyone else can drill with a small pilot or no pilot. I get mostly chattering and squealing sounds when I try to do that. My current drill press was $150 on craigslist. Jet, made in Taiwan, with 1/2 hp motor. Lowest speed is 200 rpm.

 

[BukitCase]

If you expect any more projects like this one, you owe it to yourself to at least LOOK at mag drills - the mentions of rotabroach, annular cutter and mag drill refer to the SAME THING - re-read my post#29, here is the drill I have

https://www.ohiopowertool.com/p-2420-hougen-portable-magnetic-drill-2-38-swivel-hmd917s.aspx

Not cheap, but every time I drill a hole larger than 7/16" I SMILE instead of GROANING. Especially if I have to do more than a couple.

There are MUCH less expensive versions, but regardless of which you choose the "swivel base" option is worth it's weight in smiles... Steve

 

[St-rider]

A little expensive but very clean. They use compressed air. We put these on the drill machines we make for drilling datum holes in nickel alloy IGT blades.

https://www.exair.com/index.php/buy...-cooling-products/adjustable-spot-cooler.html

https://www.mcmaster.com/vortex-tube-coolers

 

[sberry]

We need a couple pics, how many holes each piece? How much steel moving handling? What position is it all in?

 

[mcbane]

We need a couple pics, how many holes each piece? How much steel moving handling? What position is it all in?

Photo of pallet of completed parts given to contractor, along with a barrel of a325 bolts. Most parts have four holes, some have two, and the handful at the front of pallet have no holes.

 

[matt_i]

Flat and angle, shear and punch are right in the wheelhouse of the ironworker.

Good job getting them all knocked out.

Did you also have to paint (prime) them?

 

[mcbane]

Had to prime but masked the areas to be welded so the welder doesnt need to spend time grinding. The welder is still going to have to apply rattle can paint over the weld areas.

 

[sberry]

Yes, small enough to handle. Not that its a deal now but I doubt I would have drilled them, would hae seen if I could have found a friendly fab shop with a punch, fixxed up jig and banged them. Lots of times flame the paint with a torch vs grinding. Spatter really sticks to ground and a lot of field welding tolerates a little paint.

 

[mcbane]

Parts got bolted in yesterday, and today the welder is making the remaining connections. Always a relief when everything fits.