Making a screw hole through butyl tape

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FairweatherDave

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What it says really........any tips? I'm refitting my windows and having put the windows back in with the tape behind I have screw holes I need to clear. Its quite sticky and poking a rotating drill through dragged plenty up and down the drill....its stretchy......
Should I just use a nail? Should I use the drill in reverse action (undo) so to speak. Reckon I'm going to find this a tedious job. I'm sure I will crack it but anyone with a great solution?
 
What I did in the same situation was to put a strip of Butyl above and below so the screw went through without touching the tape. I also fitted a stainless washer on the screw so when tightening, all the tape wasn't squeezed out. Start tightening the screws in the centre and work outwards. Worked for me.
 
If you get a piece of thinwall steel tube of the right diameter (i.e. a bit less than the diameter of the screws) and bevel one end then mount it in a drill, that will cut rubber. A twist drill will tear the rubber.

Using water as a lubricant makes cutting rubber much easier.
 
A couple of days ago I fitted new side windows in the SClub tractor with pop rivets. I bedded the polycarbonate on a butyl strip. The darned stuff was a s..d to drill through & dragged as the OP seems to have found. I did wonder if a piece of 5mm rod heated up with a blow lamp, or a soldering iron pushed through the hole might have helped once I had drilled through the polycarbonate. Might have even melted through the polycarbonate as well, so I would only have had to drill the metal backing. I never actually got to try it though.
 
FairweatherDave said:
What it says really........any tips? I'm refitting my windows and having put the windows back in with the tape behind I have screw holes I need to clear. Its quite sticky and poking a rotating drill through dragged plenty up and down the drill....its stretchy......
Should I just use a nail? Should I use the drill in reverse action (undo) so to speak. Reckon I'm going to find this a tedious job. I'm sure I will crack it but anyone with a great solution?
Click to expand...

Stuck short pieces of wire coat hanger through a couple of holes when I did mine, the rest were ( or should be) aligned to just poke the screw through.
 
If it is self tapping screw then i would just let the screw pierce its own hole. If it is threaded screw/bolt I would use a small metal tube that just fits and file/grind a taper in the end of the bore till you get a sharp end, If you push that into the hole and give it a push and a twist it should cut the tape and the push the butyl plug inside the tube,

David MH
 
Well thanks for all the ideas. I will be fitting interscrews (barrel screws) but today fitted 32 M3 30mm bolts to pull the windows tight (but not too tight) against the butyl. My technique was a fat sailing needle followed by a coat hanger wire....both dipped in a fairly concentrated soapy water to act as a lubricant. Worked pretty well but even so one thread got coated with butyl....basically once it gets friction and generates heat it really goes like ultimate stretchy chewing gum. So I will credit Seals + Direct for calling me back to suggest the washing up liquid....yes it is obvious once you think about it but they were very helpful. Might try the hole punch on the refitting of the portlights. They have fatter interscrews.
 
I did mine last spring 150 odd holes I think it was and as mentioned the hole punch method worked well ... just played the tape on which was perfect width of the frame, made the holes clearing the tip of the punch with each one then put frame in and just did up till butyl just started to show past the frame, no leaks so all good.
 
It's funny. I suggested a soldering iron when I called Seals + Direct for ideas and they didn't come back with that. It would certainly make a hole but I think it might get really messy. I've just spent half an hour searching for my stash of little used tools and discovered my hole punch probably last used about 15 years ago.
 
Well my knees are throbbing but I'm still married! We completed 79 interscrews....(glad we all read this in the context of refitting windows?). The butyl tape was removed from each hole by manually pushing a drill bit through, twisting about and then pulling off what had stuck to the bit. A poke through with a small screwdriver and a visual and then we fitted the I terscrews. Despite that at least 20% needed a second attempt to clear butyl that had bound onto the thread and blocked the interscrew. Maybe 3 reused interscrews split as the butyl made the screw too fat for the barrel
 
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