More boring steel beam drilling questions

[Conor]

I've three 18mm holes to drill through a beam with 7mm web. Obvious choice is a mag drill but I cannot justify the cost (drill hire, transformer, annular bit) for just three holes.

 

So, 18mm HSS twist drill, TCT holwsaw or traditional bimetal holwsaw? 

 

Thinking this: https://amzn.eu/d/h48Y2ur

 

I'd thought of a HSS bit, but then I'd need to buy a 12, 14 and 16 as well ideally. 

 

 

Also, I've approx 80(!!!) 9mm holes to drill, as per below. The 80mm SHS is already welded to the 203UC. Don't see any other option other than using extra long HSS bits (4, 6, then 9mm) in a normal drill. I doubt I could drill the flange from below. I do have a portable stand/press that I can clamp. Any other smart thoughts?

 

 

 

 

[Miek]

https://www.orbitalfasteners.co.uk/products/18-x-55mm-versadrive-carbidemax-tct-holesaw-hmt-101030-0180

 

 

I've used these , very good quality and fast drilling even in stainless but costly.

 

For only 3 holes I'd use a HSS starret holesaw. Don't push hard and use cutting oil

[Roys]

Are you across the water in Stranraer end of this week, I am and you are welcome to borrow my mag drill.

[Pocster]

I bought a mag drill off Amazon I think . Not expensive and seems good . Will sell it on when done to recoup some of its cost .

Edited February 26, 2023 by pocster

[SiBee]

Try the cutter you linked. The one Miek linked also looks good but expensive like he said. Twist or jobber drill could do you an injury by throwing you around the drill! Apologies if you have skills👍 I wouldn’t fancy a Starret holesaw tbh, just seem to blunt very quickly. However, I drill Unistrut regularly and these fly through and seem to last: https://www.cef.co.uk/catalogue/products/4335977-18mm-sheet-steel-holesaw

Not ideal for a 7mm web but with cutting fluid and taking it easy,I wouldn’t think twice about using this method. 

I sold a 240v mag drill the other year on a well known auction site. Had no interest for weeks until a self builder offered  me £40. He was drilling beams.

[Gus Potter]

On 26/02/2023 at 06:52, Conor said:

I've three 18mm holes to drill through a beam with 7mm web.

Hi @Conor

 

If that is glass above the small detail you have posted.. it looks a bit suspect.. the method of connection..

 

Post more detail.. if you want to avoid disappointment and want to keep folk safe.

 

It looks to me like neither your SER Engineer or the glass folk will take responsibility for this.. so it is down to you to understand the issues of what is quite complex to design.

 

To put it in a nut shell the glass folk test on a stiff test rig to verify the safe loads... what you have detailed is a mile off so you glazing won't pass muster and you SER Engineer will bail out.. read their fine print!

 

I recommend that you nut this out before drilling any holes. It may be that you can regig the detail to make it better and for less work!

 

If you want fesse up and provide the manufactures'  connection details and load tables for the track I'll chip in to give you a bit of advice on how you sort this out., not just for you but for all on BH.

 

Also your detailing.. bolt clashes and buildability.. it may be that you are using say Tekla or Revit where you are getting a depth of view rather than a true section.. it all looks a bit crap on the screen shot you have posted!