www.ultimatehandyman.co.uk

I have recently got my hands on a iron bench from the 1930’s I have removed the majority of the wood as it was rotten and managed to remove over half of the bolts aswell. However some of the bolts have rusted solid, I have grinded the nuts and have tried to hammer them thorough. I then tried drilling them out but this seemed to take a long time to make very little progress. Any tips would be great as I’m struggling to them out. Thanks

Now you've started, you have to finish..... centre drill a pilot hole then use a larger bit to drill it out. Don't worry about the threads - you'll probably have to re-tap to the next metric size up to make it work for you.

The key is having decent drill bits, not your usual "1 from a tenner pack of 30" bit. Ideally use a drill press.

Before taking the bolt nuts off you should have got a torch on them. Heat will usually help crack them. Too late now you will have to drill out as Kelly suggests above.

DWD

Are they 'through bolts' i.e. with a nut on the back, or threaded into the metal casting? As stated, heat, and a lot of heat, would probably have shifted them.

For an application such as that, if the holes are threaded, then there is a way of using Rivet Nuts rather than purchasing threading taps and threading core drill bits. I know Rivet Nuts are intended for Sheet [metal] and require a special tool, but there are ways of doing just a few quite cheaply.