Demo Questions

[CarolineSmiles]

Hey Guys! Looking to begin our bus demo tm. I was just looking at the screws used in the ceiling and not sure what to use to remove them. they dont seem to be bolts but have a small circle in the center. Have you encountered these and what did you use? Also, what size bolts are holding the seats in typically? All tips appreciated!

[o1marc]

They are rivets with a mandrel shaft in the center. The best way members have found was to use an air chisel with a sharpened blade and pointed tip bit. Use the pointed tip bit to push out the mandrels and then use the chisel to shear off the rivet heads. When you're done you'll wish you owned a bus with screws instead.

[Gdog 5651]

A pic would be helpful, if the hole in the center has a star shape to it than it is a torx fastener (requires special tool to remove it) if it is square (it requires a special tool to remove it) but I suspect you have neither of the above I suspect you have a blind(pop) rivet. The removal of which is the discussion of many threads on this sight if it is a pop rivet it can be chisled off, the head ground off, the center drilled out with the correct sized drill bit the correct size bit is the size of the shank of the fastener if the rivet hole is not going to be reused the bit size is not so important use a bit the next size up any way there is a fair amount of work to it but doing it leads to your figuring out the easiest way for you and the swearing at it develops new vocabulary and character. Gene

[o1marc]

Originally Posted by Gdog 5651

A pic would be helpful, if the hole in the center has a star shape to it than it is a torx fastener (requires special tool to remove it) if it is square (it requires a special tool to remove it) but I suspect you have neither of the above I suspect you have a blind(pop) rivet. The removal of which is the discussion of many threads on this sight if it is a pop rivet it can be chisled off, the head ground off, the center drilled out with the correct sized drill bit the correct size bit is the size of the shank of the fastener if the rivet hole is not going to be reused the bit size is not so important use a bit the next size up any way there is a fair amount of work to it but doing it leads to your figuring out the easiest way for you and the swearing at it develops new vocabulary and character. Gene

When drilling out rivets it doesn't matter the size of the bit as long as it is bigger than the hole size. Once the drill hits the top of the rivet shaft, the head pops off, stop drilling.

[CarolineSmiles]

looking like they are rivets. thanks guys
looks as if im going to be expanding my vocabulary tm!!

[EastCoastCB]

https://www.youtube.com/watch?v=7NEs9i8Bmoo&t=49s

[Gdog 5651]

Originally Posted by o1marc

When drilling out rivets it doesn't matter the size of the bit as long as it is bigger than the hole size. Once the drill hits the top of the rivet shaft, the head pops off, stop drilling.

Of course it matters what size bit you use if you are going to reuse the hole and really if you don't want to deal with the remains of the rivet. In my time I have removed probably more than 250,000 blind and buck rivets and just drilling off the head usually leaves the shank to deal with, if you don't mind that use any bit you want

[o1marc]

You are mistaken, once the tip of the bit hits the 90* transition from head to the body, the head pops off and the body can be pushed through., no damage to the hole.
I built race cars for over 20 years, used a few pop rivets in there.