Dome hads, countersink or not?

[Geoff_Jubb]

Hi Guys,
Am right in the middle of sorting my new floor and was wondering if it is a good idea to counter sink dome headed bolts that are to go on the underide of my floor, or should I just fasten up tight with the dome protruding?
Cheers,
Geoff

[thornbackflound]

Originally Posted by Geoff_Jubb

Hi Guys,
Am right in the middle of sorting my new floor and was wondering if it is a good idea to counter sink dome headed bolts that are to go on the underide of my floor, or should I just fasten up tight with the dome protruding?
Cheers,
Geoff

Good question there Geoff,i will be watching this one ,personaly i would think dome head of screw UNDERSIDE,AS NOT SHARP OR PROTRUDING ON THE SIB FLOOR,causing possible punctures from the pressure caused with weight and persons moving about.dome head as long as no rugged bits be fine

[m chappelow]

Think i would leave them as they are,,, any hole or recess that you make will be a good place for water or damp to live in .

[Geoff_Jubb]

Thanks guys,
Would you put a penny washer between head and floor, or do you think this will be a potential wear point?
Cheers,
Geoff

[jwalker]

Being a bit pedantic but do you mean pan head setscrews? Dome head bolts I've never seen and dome headed (also known as raised head ) screws are countersunk with a raised (curved) head. Just checking because, if they're under your deck, how are you going to hold them still while tightening the nuts above deck? If you use hex head and counterbore slightly under size for the hex, the head can be drawn onto the counterbore to prevent it turning.

[Nos4r2]

Personally I'd countersink them and put them in with a dab of Sikaflex 291. The floor shouldn't rot then and you'll have nothing protruding.