Broke Tap in Canopy Bow
Posted: Tue Mar 26, 2019 10:41 pm
by Spaceman
I have gone and gotten myself into a nice pickle! I was just wrapping up the last few items for the canopy the other day, and the last thing before reassembling it for good was to tap all the 6-32 holes around the canopy frame. Of course I got a little too fast on the 45th hole out of 48 and snapped the tap off in the hole. I tried everything I could to get it out with no luck, so I brought it to a machine shop in town. They weren’t able to extract it either, so they told me they pretty much ground it off, welded the hole shut, and re-drilled and tapped the hole. Sounded great, and all it cost me was a 12-pack!
Anyway I got back working on it today, touched up the paint where they worked on it, and started installing the actual canopy on the frame. Turns out they actually did weld the hole shut and drilled a new one, but it’s not in exactly the same place as the original hole was. I can’t tell for 100% sure either, but from looking at the back side I can see my original hole and there might even still be a little chunk of tap stuck in it!
So now I have this one hole that doesn’t line up with the hole in the canopy, and I’m trying the decide what would be the best way to deal with it. The two ideas I had were:
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Enlarge the hole in the canopy enough to meet the new hole in the frame. However then I’d need a much larger countersunk washer to cover the big hole, and I haven’t found anything like that yet.
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Use the hole in the canopy as a guide and drill another hole in the original location. I’m a little concerned though if there’s still a piece of tap in there, if I’d even be able to drill through it!
Attached is a picture that shows where the hole in the canopy and the hole in the frame are relative to each other. Anyone have any other ideas or suggestions? Thanks!!
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 12:09 am
by Spaceman
After thinking about it some more, I think I’m going to have to suck it up and try drilling through the original hole. Even if the hole gets a little messed up I could just drill it a bit larger and use a longer screw with a nut, rather than tapping it again. I think if I try to make the hole in the canopy match the new hole in the frame there’s no way it’ll look decent!
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 6:56 am
by sonex892.
What a bummer. I doubt you will be able to get the tap out now they have welded over the top of it. I doubt you will ever be able to drill through the tap.
It appears to be the rear bow, If it is the rear bow? I would thought put an aluminium strap about an inch or a bit wider on top of the plexiglas and cover the entire bow to hide it. Good luck with it.
Steve
Sonex 892
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 7:05 am
by Stogie6
There goes your Bronze Lindy!
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 8:05 am
by Spaceman
Yeah it’s the rear bow. Not too worried about the Lindy!
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 9:35 am
by GordonTurner
I haven’t done the canopy yet so I don’t know much about it. Can you fill the plexi hole with clear (silicon?) or whatever substance fills it, and drill a completely new hole half an inch away?
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 9:46 am
by Rynoth
For what it’s worth, I actually used longer bolts with nuts on all of my canopy/windscreen bow holes so I wouldn’t have to worry about the screws backing out over time (since we can’t use loctite, though I think some have used silicone sealant as a threadlocker.) Nothing wrong with going this route unless you don’t like the aesthetic of the nuts on the inside, even if it’s for just 1 hole. You could even paint the nut black to somewhat hide it visually, but it’s probably one of those things that only you would notice down the line.
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 9:52 am
by builderflyer
You mean like this, Steve. I didn’t break a tap but thought the “strap” would be a good way to go considering that I used cherry N rivets to attach the canopy to the frame.
Art,Sonex taildragger #95,Jabiru 3300 #261
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 10:07 am
by Bryan Cotton
GordonTurner wrote:I haven’t done the canopy yet so I don’t know much about it. Can you fill the plexi hole with clear (silicon?) or whatever substance fills it, and drill a completely new hole half an inch away?
This is what I’d do. Drilling out a tap will make it perfect because you would end up replacing all the parts after the disaster.
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 10:46 am
by Spaceman
Bryan Cotton wrote:
GordonTurner wrote:I haven’t done the canopy yet so I don’t know much about it. Can you fill the plexi hole with clear (silicon?) or whatever substance fills it, and drill a completely new hole half an inch away?
This is what I’d do. Drilling out a tap will make it perfect because you would end up replacing all the parts after the disaster.
Haha so are you saying try to drill through the original hole, or don’t even try because I’ll end up destroying everything?
What’s a good filler for plexiglass? Some kind of epoxy?
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 11:08 am
by Bryan Cotton
If the tap is in there you will never drill through it. If the tap is out you may be able to drill all the way through and use a screw and nut.
Re: Broke Tap in Canopy Bow
Posted: Wed Mar 27, 2019 2:35 pm
by sonex892.
builderflyer wrote:You mean like this, Steve. I didn’t break a tap but thought the “strap” would be a good way to go considering that I used cherry N rivets to attach the canopy to the frame.
20190327_063358-1.jpg
Art,Sonex taildragger #95,Jabiru 3300 #261
Yep thats what I meant Art. Jeff Schultz also has the same look trim on his and it looks pretty neat. https://youtu.be/ovAGCF5KIEc?t=514
Re: Broke Tap in Canopy Bow
Posted: Thu Jan 30, 2020 8:27 pm
by pfhoeycfi
builderflyer wrote:You mean like this, Steve. I didn’t break a tap but thought the “strap” would be a good way to go considering that I used cherry N rivets to attach the canopy to the frame.
20190327_063358-1.jpg
Art,Sonex taildragger #95,Jabiru 3300 #261
Was that strap difficult to make and form to the canopy? I have an just over an 1/8 gap on top and thought a strap might save the canopy.
peter
Re: Broke Tap in Canopy Bow
Posted: Fri Jan 31, 2020 7:37 am
by sonex892.
pfhoeycfi wrote:
builderflyer wrote:You mean like this, Steve. I didn’t break a tap but thought the “strap” would be a good way to go considering that I used cherry N rivets to attach the canopy to the frame.
20190327_063358-1.jpg
Art,Sonex taildragger #95,Jabiru 3300 #261
Was that strap difficult to make and form to the canopy? I have an just over an 1/8 gap on top and thought a strap might save the canopy.
peter
This stuff is good to make templates for weird shapes like that. Can see through it to mark out with a sharpie and it cuts with scissors.
https://www.officeworks.com.au/shop/off … 0#features
Re: Broke Tap in Canopy Bow
Posted: Fri Jan 31, 2020 10:47 am
by builderflyer
Hi Peter, no that “strap” shown in my photo was not difficult to make, just time consuming. It’s been almost 20 years ago that I made mine but what I must have done is to use a large sheet of vellum or heavy paper to transfer the curvature of the canopy/turtledeck joint to a flat surface. Lay a wide enough strip of the paper so that when it lays flat over the joint you can, using a pencil, transfer the joint curvature to the paper by feel. Then cut the paper along that line. Then lay that paper flat on a sheet of 0.025 aluminum and trace the curve you generated. Then cut the aluminum forward and backward of the line leaving lots of excess aluminum in case you didn’t get the curvature exactly correct. Then lay the the curved aluminum strip you’ve made on the airplane and carefully trim the rearward edge to match the turtledeck after which you can trim the forward edge to the final width you’re looking for. Like I said, time consuming. But if you have to make a second aluminum “strap” because you didn’t like the way the first one turned out, it will go much faster since you’ll now have a better pattern to start with.
Good luck and have fun if you go this route,
Art,Sonex taildragger #95,Jabiru 3300 #261