What’s a better tool for drilling 1 1/8” holes in 1/4” plate if there’s no access to a plasma machine? Milwaukee holesaw didn’t do very well. Hate to think of doing it with a twist drill but that might be what happens. Thanks.
Oxy acetylene torch?
Or a mag base drill and a angular cutter
Would love to have a mag drill. I checking on your carbide tip saw.
I purchased a cheap Chinese Mag Drill off Ebay for $270 and 6 annular cutter kit for $74 back in 2019 when I needed to drill the frame on my Freightliner to add a lift axle. I was impressed with both the drill and the cutters. They did a fantastic job and the cutters remained sharp because I used plenty of oil. I don't have much call for a Mag Drill but I was very satisfied with what I purchased. Another recent purchase for drilling some steel was a Bauer hole saw kit from Harbor Freight for about $50 or maybe less. Their tools are getting better. I used the kit with my drill press and with the vertical mill on some projects. The key is plenty, and I mean PLENTY, of cutting oil and/or coolant air flow. The air flow keeps the chips knocked out and seems to allow faster cutting. Keep your cutting speeds low and the tool well oiled. Life should progress easier that way.
Magdrills can be rented
Depending on how precise it needs to be and how good you are O.P., I'd go with @Tags suggestion on the smaller side and then clean it up using a die grinder with burr bit.
1 1/8 holesaw drills very well. As little as 35 seconds in 3/8. About 4 or 5 drops rapid tap per 1/8 of thickness.
I've had better luck with hole saws by drilling through a piece of wood, then clamping that to the steel. The pilot bit doesn't break when the saw grabs unevenly.
I run those carbide tip hole cutters in 1/4" a lot with a hand drill. Can't always get a mag drill on things.
I drilled the pilot first. I do this on occasion and am done before most could figure how to get the drill clamped up. I looked at the mag knockoffs and its on my short list now. I was looking for the cutters too, whay ones did you get?
Took about 20 minutes to cut 4 holes, 2 each side to add bolts to keep the loader bracket from working loose. I used water for coolant.
Was a choice of adding larger bolt to worn original holes, could have went to fine thread but decided to stay with one size bolt and not fuss with hi torque. Never loosened again.
When trying to drill with a hole saw, orbit the back of the drill. This way only a small part of the saw is cutting at any one time. When the entire diameter of the hole saw is trying to cut at once you simply can't apply enough pressure to the hole saw to make it cut. Sberry, the best way to keep the bolts tight is to add a spacer and a longer bolt where the room between the frame and engine allows a longer bolt. Multiple flat washers won't help, they are to soft and springy. Anytime a bolt clamp length is less than 2 diameters the bolt is near impossible to keep tight in any type of dynamic loading.
Those were not the bolts coming loose. It was the top 2 of the 4 bolt cluster. The holes were simply worn larger and I dont think I had bigger bolts at the moment. These are 3/4 thru an inch of plates. The 2 lower bolts were added in a hole that is 3/4. If I had some 7/8 handy might have stuffed them in the holes and gave it a try but adding 2 ech side at the time seemed like a good idea and it has never came loose again. Took about 5 minutes a hole with a saw.
The pic of the saw and clamp was a 3 pt was a pain in the arse as it had smaller hole than the rest of the stuff, always has to get pin and bush instead of normal pin we use. Was simply for convenience.
I have never used one. I have heard they work well,,, whats the speed compared to a common saw? Difference in applied pressure? Seems a forum guy said they used them with boiler tube fit in end plate maybe but its been a while, believe the guy said they cut 600 with one and still was working.
I fix egg shape hol;es quite regular, fill the worn sides with weld and as long as can get the bit started back in the hole zips it back true again.
I use hole saws alot . I read that it helped to drill a small hole were the saw was going to cut so the chips would have a place to go. This sounds like a good deal i drilled alot of 1 inch holes in 1 inch steel i had to stop and clean the chips out of the cut often. I bought a blue rock mag drill it was a very good buy.
Carbide cutter speeds
Those Carbide hole saws are the cat's meow! I had a coupla sets of mower blades that I picked up at an auction, this summer, hole was too small for my machine, so I bought a couple of 24 mm carbide hole saws, replaced the center hole frill with a bushing, mounted in its place, and buzzed right through 6 mower blades, which are made of some hard stuff! Had the blades just laying on the drill press vice, not clamped. Wanted to be able to let go of the blade is something jammed. Still got all my fingers, so it was a victory!
That's good to know. I started using step bits instead of regular drill bits for lot's of jobs but will try the carbides on the bigger holes.
I routinely use Milwaukee hole saws in up to half inch plate, the key is to use low speed and lube. If you heat up the blade it's toast. Sometimes I'll keep a container of water with me and dip the saw now and then to keep it cool. Like terex herder mentioned, I'll rock the cutter in the hole on thicker material so the whole blade isn't in contact at once. Seems to help it cut better.