1.5 inch hole in mild steel-how?

I live in a very rural area. Parts are, for the most part, not off the shelf out here. I have run into the same type of projects many times were I know I can buy a part for $3 or spend 3 hours making it. Depending on how bad I want to finish the job is the determining factor in buying the part or making it. If Wall-mart does not have what I need, I have to order it on line or drive 1 1/2 hours one way to the next small town with the hopes I can find the parts I need. Usually with no success. Then I order the parts on-line and wait for 5-7 days to get it. So my choice is either work for $1 an hour or wait 5-7 days for the part to show up. Then, if I do order it, I end up getting impatient for the 5-7 wait and make it anyhow and end up with an extra part laying around the shop hoping it finds a home on another project. As long as I am just working on my own stuff, it is more fun to make it than waste 5-7 days shipping time. That is the fun of being a hobby machinist and not trying to make a profit.

D
 
Depending on how bad I want to finish the job is the determining factor in buying the part or making it.

D

You can't knock anyone for that. If you've got the material on hand, give it a go. I'm sure you'll be able to make workable flanges with a hole saw and drill. People have been doing more with less for a long time. Clickspring does it that way, after all.
 
Everybody, thanks for the advice-I've read all the responses

1. It looks like a bi-metal hole saw in the drill press is the way to go. I may upgrade to to a carbide tipped holesaw, but it looks like the annual cutters i've found require a weldon shank chuck, which I don't have.

2. The parts are for a race that is budget limited to $2,000. I can buy the correct flange for about 8 dollars a piece, but with 4 of them it would hit my budget for 32$. Buying the plate steel and making my own parts will bring the cost to maybe 5$ for everything-the cost of tooling that you use and your labor isn't included. You can see the danger here-you end up with a very fast, hand-made car for $2,000 and many times that in tools and labor =)
 
Everybody, thanks for the advice-I've read all the responses

1. It looks like a bi-metal hole saw in the drill press is the way to go. I may upgrade to to a carbide tipped holesaw, but it looks like the annual cutters i've found require a weldon shank chuck, which I don't have.
The bimetal hole saw will work just fine. I cut more than 70 2" holes in 3/16" plate and I still am using the same hole saw.
 
IMHO, As long as they are run at the proper speed and coolant is used, hole saws will last longer cutting mild steel than cutting most woods.
 
2. The parts are for a race that is budget limited to $2,000. I can buy the correct flange for about 8 dollars a piece, but with 4 of them it would hit my budget for 32$. Buying the plate steel and making my own parts will bring the cost to maybe 5$ for everything-the cost of tooling that you use and your labor isn't included. You can see the danger here-you end up with a very fast, hand-made car for $2,000 and many times that in tools and labor =)
Just be aware you'll be up against competitors who are lying like a rug about building their car for $2000. BTDTNA You'll see a well-sorted race car with a pro-built roll-cage come in and the notes are something like: "My brother-in-law is a NASCAR fabricator, so we got scrap tubing out of his shop bin and he welded up the cage for a six-pack last weekend. The engine was just thrown together from leftover parts from race engines we built back in the day; didn't pay anything for them. The race tires and wheels are from a team which went broke and we got them free for helping our friends clean out the building."

jack vines
 
To the OP. Another tip to speed up making 4 of them is cut the steel into four square pieces of equal size. Then stack the pieces and take your mig welder and run a couple of bead down two opposing side. Then mount the stack in the drill press and drill them all at once. One layout and one setup is all you need that way.
Grind the welds off separate the parts and finish the outside with a band saw or belt sander or whatever you have. You may even be able to finish most of the outside before taking them apart.

D
 
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