TonyF
Silver Member
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Good catch, I misread it!
Drilling a lot of 1/2" holes, best method
- Thread starter Paddy
- Start date
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Good catch, I misread it!
turnkey4099
Elite Member
From someone who spent 10 years behind a big drill press in a commercial producion facility:
400 1/2" holes through 1/8" in iron would have been turned out before coffee break.
It is a 1/2" hole. That is high speed drill time and cutting fluid is highly recommended. Constant flow while drilling. If you don't want the expense of a coolant pump, just hang a gallon jug up above with a tube and some method of controlling the flow down to the work piece.
Clamp scrap to the press table so the tubes just fit with a stop at the end. Place tube in jig, pull handle, remove, place tube, pull handle, repeat until your right arm wants to fall off
. My press had an automatic feed but I may not have used it on that job. It takes longer to say than it does to do.
One sharp 1/2" drill bit will probably see the whole job. I would use one of those "For hard metal" bits. Usually found with a 'gold' color.
Be sure the rods will _fit_ a 1/2" hole. You might need to go to a 33/64" bit.
OOOPS. I was picturing one hole per tube but I bet you are talking a _series_ of holes down the length. Gets a bit more complicated but will still call for jigging up. My method would be to get the first hole and then slide forward until that hole lines up with a round that drops into the hole to space each subsequent hole. Probably would have taken me about an hour to design/build/get welded the jig so figure I would turn it out by noon. The jig would also include a toggle clamp to hold the tube while drilling. You don't want the tube 'climbing' the bit as it breaks through .
The suggestion to 'farm it out' is good if the checkbook will stand it.
Harry K
Harry K
400 1/2" holes through 1/8" in iron would have been turned out before coffee break.
It is a 1/2" hole. That is high speed drill time and cutting fluid is highly recommended. Constant flow while drilling. If you don't want the expense of a coolant pump, just hang a gallon jug up above with a tube and some method of controlling the flow down to the work piece.
Clamp scrap to the press table so the tubes just fit with a stop at the end. Place tube in jig, pull handle, remove, place tube, pull handle, repeat until your right arm wants to fall off
. My press had an automatic feed but I may not have used it on that job. It takes longer to say than it does to do.One sharp 1/2" drill bit will probably see the whole job. I would use one of those "For hard metal" bits. Usually found with a 'gold' color.
Be sure the rods will _fit_ a 1/2" hole. You might need to go to a 33/64" bit.
OOOPS. I was picturing one hole per tube but I bet you are talking a _series_ of holes down the length. Gets a bit more complicated but will still call for jigging up. My method would be to get the first hole and then slide forward until that hole lines up with a round that drops into the hole to space each subsequent hole. Probably would have taken me about an hour to design/build/get welded the jig so figure I would turn it out by noon
. The jig would also include a toggle clamp to hold the tube while drilling. You don't want the tube 'climbing' the bit as it breaks through .The suggestion to 'farm it out' is good if the checkbook will stand it.
Harry K
Harry K
mostly_gas
Super Member
Find a friend with a Bridgeport or equivalent :thumbsup:
Tony_S
Silver Member
Maybe check with a larger machine shop in the area, or even some manufacturing facility that might be making use of a multi spindle drill. You know they're out there....somewhere.
They are new ground rods, 1/2" by 10'. At the place where I work, they were getting out of the ground rod biz. China makes them now, go figure.
I bought 400 of them for $250.
For the hand rail inside, I want them to turn "old penny" Cu brown. Now they are shiny copper. For the outside the green patina might look good
Patrick T
I bought 400 of them for $250.
For the hand rail inside, I want them to turn "old penny" Cu brown. Now they are shiny copper. For the outside the green patina might look good
Patrick T
I'm looking for a machine shop that is more equipted. First quote I got was for $1200 for 900 holes. I can modify the design to use punched channel on the top where a cover rail and channel make the top part. But by the price, they must just be doing the same thing as I would.
Turnkey,
The rods are actually under 1/2", about 0.470". A 31/64" drill was a good fit on the dozen holes I drilled. Ground rods are not very precise.
I too was thinking jig for this process. No one wants to layout hundreds of holes. I figure a machinest vise can be secured to drill press table with movable jaw towards operator. This sets the 1/2" hole in the center of the 1" tube. A 1/2" dowl on a door hingd that would be set 4" from drill bit would set the 4" O.C. It's a hand rail so a bit of "waggle" what not be noticed.
I have done a mock up of one section and the Black iron and copper look real nice
The rods are actually under 1/2", about 0.470". A 31/64" drill was a good fit on the dozen holes I drilled. Ground rods are not very precise.
I too was thinking jig for this process. No one wants to layout hundreds of holes. I figure a machinest vise can be secured to drill press table with movable jaw towards operator. This sets the 1/2" hole in the center of the 1" tube. A 1/2" dowl on a door hingd that would be set 4" from drill bit would set the 4" O.C. It's a hand rail so a bit of "waggle" what not be noticed.
I have done a mock up of one section and the Black iron and copper look real nice
TDVT
Silver Member
You should check out this thread
Annular Cutters
I wasn't aware of them before I read it but have been fabricating some implements & it's definitely the way to go. It was a few $$'s to get set-up with the cutter holder but I've been pretty happy with the results.
I think they're typically used for heavier material but they do thinner stuff fine.
Annular Cutters
I wasn't aware of them before I read it but have been fabricating some implements & it's definitely the way to go. It was a few $$'s to get set-up with the cutter holder but I've been pretty happy with the results.
I think they're typically used for heavier material but they do thinner stuff fine.
turnkey4099
Elite Member
I'd have to see one in operation to believe it would be faster than a standard 1/2" drill bit.
My experience with hole cutters is not friendly. Trying to get the cut-out discs out of them is not easy.
Harry K
