My dear, sadly gone uncle had one just like it. He never owned a screw of sufficient size to do it justice but there wasn't a congealed paint lid in his shed that could resist its leverage, after which, he would invariably spend 10 minutes stirring the paint with it. We reckoned if he took an angle grinder to it, it would look like the cross section of a gobstopper.
That's a task and a half JM coz that Allen bolt has 48 Nm on it, suggest the largest screwdriver bit of an impact set rapid tapping on the bolt . The head of the bit should have a 10mm socket which would enable you to use a conventional extension and ratchet. Good luck bud
I had a rounded out Allen bolt on my tail tidy! I used a Allen key and copper mallet to tap it loose works 99% of the time. Now I always put wd40 or plusgas the night before to soak in and hey presto no problems
I remove loads of snapped bolts each year for people, tricks are: weld a nut or bolt to broken one and undo while hot, heat bolt, star bit, dot punch, chisel, easy outs (not good as expand the bolt), Snap On bolt/stud extractor (looks like a drill chuck), get the wife to moan at it , go to church once a week, olive oil (kidding) or the best tip of them all!!! and you heard it from me first.... my age old best tip a LEFT handed drill bit! As it bites (drill slowly) it often winds out the bolt before you drill through, center punch it perfectly and sometimes if it fails you can drill it out so well you can just clean up the threads and job done. IF you fail Wurth timeserts are better than H coils.
Hi Arthur, Thanks for sharing those tips, Knowledge like that can be expensive to learn. And take many years to accumulate. Mike.
We make left hand cutting and helix drills and endmills (slot drills) at my place, normally used for jobs where the work holder isn't secure enough for the piece to be cut as it applies a downward force as cutting, instead of the material trying to climb climb up the drill or endmill.
I'm sure they have hundreds of applications but yonks ago I was well chuffed when drilling out a bolt and thought "if only I had a left handed drill bit" moments later, ordered! Since then they work a treat for those nasty snapped off bolts and studs..
The moral of this story is "when you discover a problem, don't focus on it so much that you miss the bleeding obvious"... because...I have since realised that the number plate holder assembly comes apart, revealing the nuts on the other side of that bolt I had so much trouble removing twat!