What Size Drill Bit

Sawdust

Sawdust

Jim from Kentucky
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do you use for an oversize hole for round bar stock. I want to buy three drill bits for 1/2", 5/8" & 3/4" round bar to move freely in. I was thinking 1/64 over would work good until I was looking at a poorly drawn drawing plan. This drawing was for a rear grader blade using a few 5/8" holes. Their specs showed both a 1/32 over & another a 1/64 over. Before you wonder why I just don't try both is because I don't have either. I'm a retired woodworker with most any bit you would need for wood. Once I get over 3/8" I use spade or forstner bits.
 
I'm thinking I'd stick with the same exact size. Especially if it's thinner materials you're going thru. If it were inches thick it would different. JMO.
 
4getgto said:
I'm thinking I'd stick with the same exact size. Especially if it's thinner materials you're going thru. If it were inches thick it would different. JMO.
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You have to drill over. Oddly as it sounds you can't get the same size bar through the same size hole. Most my projects are drilling through 1/4 to 1/2 inch flat stock. I've been reaming in the past & getting tired of it. A little arthiritus has been showing up lately. I think it's about time to pull the trigger on a few larger drill bits.
 
Depending on what I'm doing, I'll use 1/64" over. If it's parts that are being welded together, they can move ever so slightly during that. Have had to redrill at 1/32" to get things to fit. If it's a hole that the bar will be welded in or pivot inside of, the smaller the better.
 
It depends on the type of round stock I'm using and what type of tolerance is needed. If it's cold rolled then I use the same size drill bit as it is dimensionally uniform. Hot rolled is not so using a little larger bit is a good idea. When in doubt drill a hole in a piece of scrap and see how things fit.
 
Measure the shaft your going to use first and go from there. Most round stock is listed at nominal size, so could vary from piece to piece. Also some drill bits are not exactly the size listed, especially the cheaper ones. Digital calipers are inexpensive and save a lot of time and frustration. I use a 6" from HF and it is dead on with my calipers on outside measurements. Does get off a couple thousands on inside readings but normally not doing that kind of precision work. .
 
Why don't you use a reamer with your drill? I think the reamer result is way better than the drill result
 
I use reamers in the metal lathe when I need precise diameter holes. They are not that expensive and the shank can be cut down for easier use in a hand drill or drill press. Need the longer shanks to clear the cross slide on a lathe.
 
Ordered a 33/64" bit to over size a 1/2" hole. It's just what I needed. The quality of the bit is good too. I'm going to order a 41/64" for 5/8" hole & a 49/64" for 3/4" hole. I have some reamers for smaller holes but nothing this big.
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Ive had an
chieffan said:
Going to get expensive fast buy one bit at a time. Better check into getting a quality set and spend much less per bit.
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chieffan said:
Going to get expensive fast buy one bit at a time. Better check into getting a quality set and spend much less per bit.
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I've had a life time supply of top quality machinist bits all my life. My dad was a retired machinist that worked where they would discard all bits with broken tips. These are top quality bits. My dad had me sharpening bits when I was in grade school. For some reason these three are the only bits I don't have. I'll have less than $50. in these.
 
Cvans said:
You should thank your Dad for teaching you how to properly sharpen drill bits. From my experience it seems most people do not know how.
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I also learned how to pull nails, straighten, then put them in my own baby food jars he saved. He would bring home 1x lumber from crates full of nails. We would have shop time while mom fixed our family traditional big breakfast on Saturdays. Being a trim carpenter most of my life I refuse to waste nails & screws. Great memories
 
Cvans said:
You should thank your Dad for teaching you how to properly sharpen drill bits. From my experience it seems most people do not know how.
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I don't know how with just an emery wheel but I can sure screw one up. My new Drill Dr. does a gerat job.

Sawdust said:
I also learned how to pull nails, straighten, then put them in my own baby food jars he saved. He would bring home 1x lumber from crates full of nails. We would have shop time while mom fixed our family traditional big breakfast on Saturdays. Being a trim carpenter most of my life I refuse to waste nails & screws. Great memories
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When I was working construction wood shingles was about the only thing available. One corn crib job the owner would pick up all the nail every evening and put them back in the box, along with some grass and dirt. Real pain in the butt sorting nails out of the crud in a nail apron.
 
And some farmers went the other way. One wanted/needed new wood shingles on a barn roof. His wife was dead set on a green roof on that barn. Cedar shingles don't come in colors. She said stain them green. So he bought a horse tank and who knows how much green stain or dye or ?? and he stained the shingles and we nailed them on. Took 3 extra guys to carry shingles to the guys on the roof as they wewre not bundled. He paid with no question including a new pair of carpenter overalls or jeans for the whole crew. Only barn in the Midwest with green wood shingles. Never did go back and see how it held up as I never wanted to see a green wood shingle again.
 
At least he knew to stain them before you put them on. I did a job putting wood shakes on the side of a house late in the year. The home owner primed all four sides of every shingle white. I suggested him staining them too because they'll shrink come summer. He disagreed so I installed them primed. He stained them a dark brown with a sprayer. It looked real good for awhile. He never made it through the winter. He had thousands of little white vertical lines everywhere.
 
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