mad_pete Posted June 13 Share Posted June 13 So in my quest for soft top seat belt mount options option 2 is weld in a FIA approved threaded insert on both sides in the cage. the insert is 20 mm diameter so the question is how best to put a round straight hole through the roll cage upright ? the cage is 1.75 inches (44 mm). Freehand feels like that’s asking for all sorts of trouble. Quote Link to comment Share on other sites More sharing options...
Stellaghost Posted June 13 Share Posted June 13 20mm hole saw Regards Stephen Quote Link to comment Share on other sites More sharing options...
sean f Posted June 13 Share Posted June 13 First you shouldn't really drill a hole in a roll cage as it will weaken the structure but I can see why you want to so that's your shout, and it has been done by others, a welded on bracket would be better if you could sort something out. Otherwise as Stellaghost has said a hole saw and as carefully as you can using oil to keep it lubricated and not getting the cutter to hot is probable your best bet. If you could get the roll cage into a pillar drill or milling machine that would be better but I am assuming that's not an option, only other thing I can think of is if you could get hold of magdrill and cutter, not sure if it would attach to the roll cage or not with it being round (anyone else know?), might be possible to clamp a flat plate on to hold it in place if it doesn't, all depends on the room available and the amount of work you are willing to do. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 13 Share Posted June 13 Christmas tree bit should also work for you. Drilling a roll cage is fine if you are fitting an FIA approved insert, I would suggest Quote Link to comment Share on other sites More sharing options...
mad_pete Posted June 13 Author Share Posted June 13 Right I’ll be putting a big chunk of metal in the hole welded both sides as per the fia spec I was linked. I did look at mag drill hiring. One issue is on one side I can only get to one side of the tube as the diagonal largely blocks the other side. Hole saw may be long enough. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 13 Share Posted June 13 Mag tends to only really like flat surfaces, on a tube it would be tricky. Quote Link to comment Share on other sites More sharing options...
bishbosh Posted June 13 Share Posted June 13 Hole saw will be fine I am sure for a roll cage tube. If it isn't you can get extensions for the shank but I'd doubt you'll need it for a perpendicular hole straight through the tube. Worst case, drill right through with a 6mm drill bit to start then you have a pilot hole each side to start the hole saw on. 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.