Tips on how to drill vertically on a sloped surface

[Trebor72]

Hello
I am going to replace the stair railing in our indoor stairs.
We will insert round steel rods down into the stringer.
The question is how to drill the holes so that they are absolutely vertical?

Attached is an example image.

 

[PNO]

Take a wooden block, drill a hole straight through it at a right angle. If you're unable to do it freehand, ask for help from someone who has a drill press. Then saw the wooden block at the correct angle for the staircase. A miter saw is good for that. Then use the block as a drilling template.

It might be a good idea to screw a plank piece to the side of the block so you can clamp the block to the stringer.

 

[JSten]

As a suggestion, make a guide piece/template. That is, take a piece of wood with about the same thickness, drill a hole through the entire piece using the same drill bit you intend to use on the steps. Once that's done, saw the piece in half with the same angle as the steps have (in relation to the rods). Then you can use the piece to "start" the hole.

Here is a rough illustration I threw together in paint, seen from the side:

Dashed lines are the "sides" of the hole through the wood piece. Then you saw along the gray line.

Edit, I block pucktvåa on that, PNO managed to get there first

 

[Trebor72]

Thanks for the tip.
I will probably have to make several I suspect since the vangstycke has a wavy shape. There are two 90-degree turns.

 

[pleqtiz]

Maybe a jig like this? https://www.axminster.co.uk/ujk-technology-drill-guide-with-10mm-chuck-106072

 

[Trebor72]

A jig like this perhaps? [link]

Yeah, a gadget. However, I think it will be difficult since part of the vangstycke is flush against the wall.
I don't think it can be done with that.

 

[jonaserik]

With a wooden fixture, it will go downhill after just two holes; the drill will want to dig downward as the carriage is not flat against the fixture. Measure and mark all the dimensions and any angles you need, then go to a blacksmith or metalworking company and buy a metal fixture and tubes for guiding the drill. At the start of drilling, you must not press too hard; the drill must start to bite without sliding off the fixture, and it should be a metal drill and not a so-called flat drill.