Removing broken bolts from trench drain

[misterdobalina]

So I know every forum (GJ included) has done this question about a billion times but I am not having an easy go of it.

Around my garage is a trench drain, and the previous owner at one point managed to break off no fewer than six of the grate-retaining bolts, and lose a bunch of the hardware. So I have two problems.

1. As you can see in the photos, the bolts are broken off flush. Screw extractors don't work (maybe the bolts are too hard?) . As I try to drill the bolts out, I break small bits, and the larger bits just don't get any traction. I can't remove the drain (it's cemented) so some of the usual workshop tricks (heat) are not as straighforward. If I could get a vise grip on the bottom of the screw, I could try to take it down (rather than up) but I have no range of motion to do this. What's my next step? Do I just need better quality drill bits or something?

2. You can also see one of the retaining hardwares in the photo. Finding this specific part is going to be impossible, right? So how would someone with only a rudimentary workshop go about making new ones?

 

[southalabama]

Drain stainless?

Harder bit gonna be my guess.

 

[58Yeoman]

Drill new holes next to the old ones, then retap. Shouldn't be too hard finding those clamps...or making them.

 

[misterdobalina]

Harder bit it is, pending other recommendations. Got a brand and size recommendation?

 

[misterdobalina]

Drill new holes next to the old ones, then retap.

Heh. That's such an obvious solution I am a bit embarrassed not to have thought of it.

 

[justin1795]

we use a similar clip at work called a grating clip. its a safety requirement now.

 

[Balor]

Spray some PB Blaster on for 24 hrs. then Tig weld nuts on too the broken bolts, the heat along with the PB will allow the bolts to turn right out. RNGR1

 

[crf731]

We use these clamps all the time at work to hold down grating. Do a google search for "grating clamp" to find where to buy them.

We usually just use 1/4" self tapping screws to fasten them down.

I'd just grind the old bolts off and either drill a new hole and tap it or use a self tapping screw.

 

[readhead]

We build a lot of these drains and the only time we use clamps is for gov. speced jobs. The grating will stay in place. It won't fall up. When we use clamps we install a bolt and nut so if anything fails you just install a new bolt and nut.

 

[Herb]

Yep, drill new holes, tap and use stainless bolts.