Dave,
It seems we basically agree; "mag bases are the way forward".
In ten years heavy boiler work I have never used a drilling pillar; I have watched others wasting their time wrestling with them and getting fair to poor results; but get the job done eventually. Air drills not really that good for drilling; in the same way that ratchet drills before them weren't either but I can manage the big air drills free hand if I need to (but more for bridge reaming or c/sinking than drilling) and the medium ones are useless as they (or at least the ones we have) spin too fast for even a 1/2inch drill which an decent electric pistol drill will handle anyway.
I also do the ratchet strap fixing for a mag base thing and have made a ratchet strap fixed mag base base specifically for barrels using about 15" of large channel about 8"x3" cutting ratchet strap shaped slots in the flanges of the channel towards each end so the channel device can be strapped to the barrel "legs" down and the mag base sat on the web. I have also made one with odd length legs for when working around a doubling plate so longer leg sits on the barrel and the other sits on the doubling plate but the part where the drill sits is still generally tangential to the barrel.

I have used an air drill a lot, yes it takes a while, but in all fairness not much slower than with a mag drill when you can feed it through on a strong arm, There is no way anyone I know can push a twist drill of any size through free hand, whilst holding the drill square and also more often than not in an awkward position, Like you say with using the decent sized ones.

I have sent you a PM. :-)

One advantage of a drill post and drill is the weight, you can add each part one at a time, a mag drill you can't always, if you can't turn the job over and can't use a hoist it becomes an issue. These guys still use them, http://www.2857.org.uk/2857_28xx_news_2007.html sorry for the manual link, can't use the button on this viewer.

we have used air drills and other air equipment for all boilermaking applications for more than 20 years. our air tools originated from the shipyard here on the island - j s whites. all on site holes were made with a drill post and air drill. i find it quicker to set up than a mag drill and is far more flexible in use. corner drills for awkward holes . we drill , tap , ream, tube expand etc.the necessity is having suitable drilling machines and these are expensive

Dave, I don't know what air drills you have been using but all those that I have used and was using this afternoon drilling 25/32 holes have speed controlled with the twist grip which is totally variable. Yes I do own a mag drill :D and it is very good for small holes but any thing 1/2" and above is best done with the air drill and as for you using a large air drill free hand, be careful as it will bite you one day and you will go around with it :confused:, and yes its happend to me and have the scars to prove :o, Use a drill post. The other good thing about air drills is you can stall one without damaging it, Stall an electric drill to often and you chance buggering it.
Happy Steaming. ;)

Kieth, I think you have miss read the thread, do you mean Phil? For drilling with an air drill I use a strong arm, for other operations, reaming etc, free hand is more than adequate.

I do say though, you can go much larger than 1/2" with a Mag drill, I only have a little Mag drill and drilled my tube plate it it, they were getting on for 2" holes. 20 mm Rivet holes are easy and fast with any Mag drill I would say. Have faith in your Mag drill!

:)

Some time ago I had no option but to use a ratchet drill simply because I couldn't get any magbase into the obstructed area. I was lucky to get some tips from Henry Netherway and after a short time I was amazed at how efficient it was. I had to drill 6off holes, 1.5" diameter x 4" deep. It took me two days 'off and on'. Physical work but I had no other option. Ordinarily my magbase or radial drill would win every time.
Cheers Carl.

generally i use the radial drill as much as possible even if i have to spend some time setting up just to drill one or two holes as it is so effortless with the auto feed. mag drills we have drifted away from them as they are big, heavy cumbersome items and generally you can do the same job with the radial. air drills we use mainly for reaming and counter sinking but occasionally i use it for drilling holes like in the image below. as it is easier than fighting with a mag and obviously i can't get the radial there to do the job either way pro's and con's for all 3 but the air drill does do a super job if you can use the tail screw to get pressure onto the drill.

http://www.tractiontalkforum.com/pic...ictureid=17263

regards sam

Thanks for that piccy Sam , just the smokebox detail I need tomorrow !

Sorry Dave, you are right I did mean Phil. :o ;)