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By Bet
#59153
Never heard boobs called rawl plugs before. Does this mean you can go to B&Q and get a packet of boobs?
By Dennis C
#59157
In an effort to get to page 3 and also to educate those that think all self tapping screws are the same, if it works?, a picture of just some of the different types.

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By ed.lazda
#59162
2 thoughts: what plastic is it made of? If, as seems likely, it's ABS, then get some methyl ethyl ketone (off ebay) and some scrap ABS (bits of old fairing, lego bricks) and make a thick solution of ABS in MEK. Use that to fill the hole, let it set for a few days, then tap it. Or, better, get a plastic insert with a brass nut (ebay again) and use the MEK/ABS solution to stick it in place.
By jefrs
#59164
I'd go for screws the correct size i.e. the next size up, that cut out and re-thread the material like a tap - types D F G T AT



This screw has to provide a 'mechanical joint' in that it is used in tension (not the strongest method) and relies on its threads to hold. On any screw only four turns of thread provide that strength and as you can imagine the area of those threads is less than the area of the bolt diameter.



I'm not entirely sure the plastic is ABS, if it is then it is heavily loaded with another material (alumina is often used), hence 'plastic welding' with MEK is likely to be weak. The plastic is very hard, it likes to chip rather than deform or cut, it files like a metal. Over 30 years ago I was testing these types of plastics in a lab, mixing them up in various formulations and then pulling them apart.



If the OP is anywhere near Newbury I can run a bottom-tap up it for you and find a screw to fit. I need a round tuit to do mine because I've got it to hold with Loctite.

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