Hole drilling in 3/4 ton frame

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AuroraGirl

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Does it take much to drill holes? Could I just use a harbor freight drill bit set(bulk, cheap ones) and get pilot holes and then use a step bit. I would use atf or power steering or something for lubrication with occasional splashes. I need to drill about 3/8 to 1/2 hole in three spots to mount a trailer jack because my trailer is the frame and bed of a 3/4 ton square, so thick steel. Im using a hole on the frame that exists already for the first bolt, the three others will be drilled.
 

eskimomann209

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Does it take much to drill holes? Could I just use a harbor freight drill bit set(bulk, cheap ones) and get pilot holes and then use a step bit. I would use atf or power steering or something for lubrication with occasional splashes. I need to drill about 3/8 to 1/2 hole in three spots to mount a trailer jack because my trailer is the frame and bed of a 3/4 ton square, so thick steel. Im using a hole on the frame that exists already for the first bolt, the three others will be drilled.
They’ll make it through. Make sure your speed is right for the hole size and that you are applying that lube.
 

1985c20

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Frame steel isn't anything special. I don't know how well the harbor freight drills are quality wise so I cant comment there. Biggest mistake people do is run drills at too high of a speed. Low speed, enough pressure, and some cutting fluid and you'll be fine. I had to drill some holes in the back of my trucks frame to mount my trailer hitch it went fine. If power is available I'd use a corded drill instead of cordless just so you don't have to worry about dead batteries.
 

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I have the high capacity milwaukee m18 series battery and normal size drill. I do have corded drills but they weigh about 4x as much and are about 40 years old. They definitely are quality but it gets heavy after a while.
 

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How fast would yall recommend. Can I go to step bit after pilot hole, and if not, what size increment changes?
 

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SLOW EVEN PRESSURE, FEW SQUIRTS TO KEEP THE DRILL BIT COOL, I RECOMMEND THE CORRECT SIZE FOR THE MOUNTING,IF THE MOUNT IS 1/2 USE A 1/2 INCH , NO SLOP WITH OVER SIZE HOLES.
 

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How fast would yall recommend. Can I go to step bit after pilot hole, and if not, what size increment changes?
I wouldn't use a step bit, they are made more so for sheetmetal. Mark your center with a punch and start with a 1/8 bit, slow so it doesn't walk. Then go up in standard sizes, 1/4, 5/16, 3/8, 7/16, then 1/2. You can skip a couple of those sizes if you feel comfortable and your bits are holding up. Pull the trigger slowly until you see some decent chips coming off and the bit isn't binding.
 

eskimomann209

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I wouldn't use a step bit, they are made more so for sheetmetal. Mark your center with a punch and start with a 1/8 bit, slow so it doesn't walk. Then go up in standard sizes, 1/4, 5/16, 3/8, 7/16, then 1/2. You can skip a couple of those sizes if you feel comfortable and your bits are holding up. Pull the trigger slowly until you see some decent chips coming off and the bit isn't binding.

Honestly for the frame. I use the hell outta the step drills but mine aren’t HF they’re the bosh brand. And they are bad ass. I’ll post come pics.
 

eskimomann209

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These are the ones I have. The closer steps are probably only good for sheet metal. But the solo one I have a picture of can easily cut through the frame. I have done multiple 4 links with one and never had one dull out on me pre maturely. They are nice because they spread the heat along the bit keeping it cooler.
I always center tap and pre drill before using it tho.

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AuroraGirl

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Well if that is the case for you, im sure at most 2 hf bits can handle it. I only ask because I have a LOT of free HF bits and id rather use those and break or dull em before my other brands.
 

eskimomann209

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Well if that is the case for you, im sure at most 2 hf bits can handle it. I only ask because I have a LOT of free HF bits and id rather use those and break or dull em before my other brands.
How many steps are on the ones you have?
 

AuroraGirl

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I believe it goes up to about 3/4 or so and has about 7 steps, I think. I am not near them and its cold out. I believe its this set
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legopnuematic

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If you are going to use a standard twist drill, be sure to use a 135 degree split point, that secondary cutting edges in the center help to get the hole started.
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AuroraGirl

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I ended up using the cheap harbor freight bits(but not step bits) as I didnt need nearly a 1/2 hole. The bolts I needed were 7/16-14 after noticing they were too long and went to hardware store. Ill send a picture of my shoddy work later hahaa. Its temporary to put it lightly.
 

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