Drilling a STRAIGHT hole for hinge in COMPLETED gates-how?

[mart]

I need to drill another 16mm hole in the frame of my gates to fit an additional hinge (eye bolt). The gates are a bit on the heavy side now that they are almost complete, and I want to fit 3 hinges to each side. When I drilled the original holes, the 40mm box section was just a single length that I was able to put under the pillar drill, and it was easy to drill a nice straight hole. Is there a device or any method that I can use to drill a hole “straight & square” using a hand (power) drill now that the gate is all welded up-they are not hung yet?

 

[Justme]

Make a flat plat & weld a tube / sleeve to it so that you can clamp to the tube you want to drill as a guide?

 

[astro_al]

Use a mag drill / magnetic drill. You can hire them.

Or weld on instead?

Al.

 

[rtbcomp]

Get a thick piece of wood, drill a hole through it on your pillar drill and clamp that to the gate as a guide.

 

[gavuk]

My Ryobi drill has a built in level,bit of a gimmick on this drill but a good idea badly executed,get someone to check level from the side and concentrate on left and right or
methods already mentioned

 

[gordon stephenson]

The clamp on jig is a good idea, on old dodge used to be put a loose fitting washer,
5/8" or 3/4" in your case on the drill bit shaft and as you are drilling keep the washer central on the drill bit, If the washer runs forward you are drilling down-hill and if it runs back over the opposite applies.

 

[Hitch]

I know it sounds silly, but point the drill bit straight

Take it steady, putting your eye through the line of the drill a few times.

Doesnt have to be absoloutly perfect if its only over 40mm

 

[mart]

Get a thick piece of wood, drill a hole through it on your pillar drill and clamp that to the gate as a guide.

All good suggestions coming through.Regarding this one, would you advise that i go through with say a 10mm bit first (just in case), and if i am a bit off square i still have a few mm to play with? Also, maybe i should try to obtain a bit of hardwood as i am thinking that there is less chance of the hole (in the wood) going pear shaped before i have finished drilling through the steel.
I would make a fresh hole (in the wood) for each hole i need to drill though the steel.

 

[pidgeon chit welder]

Can you mark and drill it from both sides using 3mm drill on the easy side and a right angle box in the difficult side to get two pilot holes at the required point, if so it is just a simple care of stepping up the drill sizes by a mm or two at a time from the easy side till you get the right hole you need .


If you cannot get the inside awkward hole , perhaps think of using a long twist drill for the pilot hole and do all the work from the easy side , once you have bunged the hole in the easy side use a bit of thick bar drilled to the pilot hole size on your drill press clamped at least in two places over the easy hole side hole to give you a guide .
Pencil mark around the guide to help you know it is still stuck in the correct place & slip a bit of a cut up red rubber industrial glove on the slipperiest side to help it stay in the clamped place also helps .

You can get extra long drills to use as pilot hole devices for use in hand held power drills in most decent engineering ships /websites up to about 8 inches long.

If you need longer ones like for a job I did ..I turned down the drive end of a 3/16 drill to fit a high grade 3/16 steel pipe and brazed the twist drill in the tube extending the twist drill to 11 inches long .. I used a 1 & 1/2" steel block drilled out on the drill press to 3/16 as the guide .... just take it steady , every few seconds withdraw the drill ,spray WD 40 or some lube into the hollow to lube the drill face , watch out for hitting hard spots if you are drilling into the welded seams of square tube etc. if you do hit a hard spot be prepared to take it even gentler and perhaps reducing the cutting angle and clearances of the drill to get a wee bit more drill bit on the hard edge parts to help dissipate heat and add a bit more metal to the highly stressed drill tip.

If you do hit the hard edges remember you will also hit them as you enlarge the holes so great care is needed.


This extending twist drills can also be used on masonry drills and wood drills /augers sometimes if you need a 25 inch drill for brick/ block or doors and you don't use the hammer facility etc.

 

[Paul.]

Use a 16mm holesaw in an ordinary power drill, pilot drill it first both sides of the box section, much easier on the drill, and wont snag and break your wrist, or the drill.

 

[pidgeon chit welder]

Use a 16mm holesaw, much easier on the drill, and wont snag and break your wrist, or the drill.

I did'nt realize you could easily get such small hole saws Paul ..are they made on the same principle of a lockable on detachable cup on an arbor ?

or are they a solid metal device like a "Forstener wood cutter bit " ( sorry for swearing )

 

[Paul.]

I did'nt realize you could easily get such small hole saws Paul ..are they made on the same principle of a lockable on detachable cup on an arbor ?

or are they a solid metal device like a "Forstener wood cutter bit " ( sorry for swearing )

Here you go, 16mm hole in 40mm box drilled with a cordless, about 30 seconds,
Took windows vista longer to process the picture,

 

[pidgeon chit welder]

Thanks that's ....Smart ,

I had visions of a very large arbor stopping you getting in deep but it looks quite a long cutter body , what is the depth they can cut to before the arbor fouls the work piece ?

David

 

[madkayaker]

normally 48mm

 

[Paul.]

Thanks that's ....Smart ,

I had visions of a very large arbor stopping you getting in deep but it looks quite a long cutter body , what is the depth they can cut to before the arbor fouls the work piece ?

David

about 45mm for that one, if you knock the corners off the hexagon on the cutter it will do about 60mm before it hits the arbor.

 

[pidgeon chit welder]

Cheers ..prob now solved for some plastic stuff I have .