Through drilling of the outer wrapper/firebox

[runner42]

This on the face of it appears a simple straightforward operation, but past experience has shown that it has the potential to cause problems. The boiler is a Belpaire construction and the staying arrangements between the outer wrapper and firebox is by a number of rod stays (32). The distance between the outer wrapper and firebox is approximately 2 1/2". I have drilled the outer wrapper and now require to drill through the firebox crown so that the rod staying is vertical and not canted at an angle. Unfortunately I cannot use my pillar drill and require to use a hand drill. This is where it is possible to have the drill wander off from the vertical, so I am seeking advice on perhaps using a simple jig to assist in keeping the hand drill vertical throughout the operation. Any advice is welcome.

Brian 

[jo479]

can you not swing the head round on your Piller drill and stand your boiler alongside?

[runner42]

Unfortunately no, the pillar drill is sited in a corner and although free standing which allows the bed to swing some distance, but not enough to accommodate the size of the boiler so that the outer wrapper is positioned under the drill. I have drilled by hand and although the result is not rows of rod stays that are perfectly aligned when viewed from end on, the purpose of the rod stays has been established by providing bracing of the flat surfaces. In a closed up condition the stays are not visible anyway so I am happy that the stays have fulfilled their purpose.

Brian  

[92220]

You can buy drill stands from ebay at very reasonable prices. Here is a sample:- eBay item number:180902249735 DRILL STAND FOR HAND HELD ELECTRIC DRILLS ROTARY MOUNTING PRESS PILLAR BENCH You can either search for the item number or the description. This will bring up the item page and at the bottom there are a lot of alternative options available. Hope that helps.

I needed to drill some holes in the cab platform plate that is already fixed to the chassis on my loco. That meant I had to work out a way of accurately drilling horizontally. I had a Proxxon mini bench drill which I made up into a horizontal drilling machine with screw feed to the cross direction movement. The vertical movement was facilitated by using the fact that the head could be rotated around the horizontal pillar, using a long, 3/8" BSF screws to jack the head up.. There is no reason why a similar device couldn't be made to drill in any direction. These are photos of what I did:-


Rear buffer beam drill jig by Robert Shephard, on Flickr


Img_2934 by Robert Shephard, on Flickr


Img_2936 by Robert Shephard, on Flickr


Img_2937 by Robert Shephard, on Flickr


Img_2938 by Robert Shephard, on Flickr

Bob.     Edit:-  This was made up to enable me to drill all the holes for 1/32" and 1/16" rivets in the loco rear buffer beam and cab platform support plate, which I had forgotten to drill before assembly. The drill stand base is bolted to the vertical face of the large angle plate, which ensures the drill spindle is horizontal. The angle plate is a close fitt in the steel angle, which acts as a slideway. The first photo shows the drill jig, machined up to make sure the holes were exactly where I wanted them. It also enabled me to adjust the position of the drill point to the correct position, just by lining up the drill with the jig holes.

[Deleted]

If using the hand drill one option could be to make a block that slides over the drill. If deep and wide enough it should help keep the drill square to the job. If drilling a curved surface you may need to get creative and shape the block mating face to match that of the part of the boiler being drilled while keeping it square.

Pete

[jackrae]

Attach a pair of small spirit levels phials to the top of your drill such that one is aligned with the length of the machine and the other is at right angles. You could also use a single round bubble level but, as they are relatively small are a bit harder to use than the small spirit phials. It's then a "simple" matter of keeping the bubbles centred.

[runner42]

Thanks for the replies. The e-bay reference didn't provide any suitable stand that would accommodate the boiler with a height of 9 1/4" at the outer wrapper, without considering the length of drill chuck and 1/4" dia drill. A lot of pillar drill stands would be pushing it to accommodate that size of boiler, mine does but it is sited such that it doesn't have the space around it to enable a 24" long boiler to be positioned to drill 32 holes.

Brian

[iant]

I have a Wolf vertical drill attachment that consists of a plate with two vertical bars that allows a power drill to slide up and down vertically.



With some thought (and either a Workmate or a simple ply jig to hold the work) it has been very useful in drilling long and/or awkward things that wouldn't go in my bench drill press. Much better than just 'hand' drilling and it has got me out of a few pickles...



It's similar to this one...and not too expensive


Vertical Drill attachment

Regards,

IanT

[runner42]

Yes it appears to be suitable, with the proviso that it can drill to a depth of 2 1/2", the distance between the outer wrapper and firebox crown. Depth info is not addressed.

Brian 

[iant]

My Wolf attachment will certainly do that depth Brian - although for some work I have also removed the return springs (on the vertical rods) which gives about another 1"+ of travel.

Regards,

IanT