How to tap a threaded hole?

Goose

Goose

Goose

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This is a sort of follow on from this thread where i'm attempting to attach a new window handle. The plan i've come up with so far is to fill the void left by the old handle (pictures are in the other thread) with metal epoxy putty, drill holes and then tap threads for the screws for the new handle.

I am, however, a DIY moron and I dont know what to make sure the new threads I tap are the correct ones for the screws that came with my replacement handle. I have a drill with a few small drill bits but I dont have a tapping set so if someone could recommend one i'd really appreciate it.

I'd be very grateful for any advice or links to how-to guides etc.

Thanks
 
Goose said:
This is a sort of follow on from this thread where i'm attempting to attach a new window handle. The plan i've come up with so far is to fill the void left by the old handle (pictures are in the other thread) with metal epoxy putty, drill holes and then tap threads for the screws for the new handle.

I am, however, a DIY moron and I dont know what to make sure the new threads I tap are the correct ones for the screws that came with my replacement handle. I have a drill with a few small drill bits but I dont have a tapping set so if someone could recommend one i'd really appreciate it.

I'd be very grateful for any advice or links to how-to guides etc.

Thanks
Click to expand...

How worried are you about the look?

Because tapping isnt super easy, especially until you have done it a few times

If your not that worried about the look you could switch in a few self tapping screws instead
 
Mercenary Keyboard Warrior said:
How worried are you about the look?

Because tapping isnt super easy, especially until you have done it a few times

If your not that worried about the look you could switch in a few self tapping screws instead
Click to expand...

I'm not too worried about how it looks since the window already looks horrible without a handle on it.

I guess self tapping screws probably make more sense, are there a particular type you'd recommend for drilling in to metal?
 
Tapping is quite easy. Drill the correct size hole, acquire the correct size starter tap. Put tap in hole and rotate clockwise until you feel resistance then counter rotate which will release any built up material. Repeat until hole is threaded sufficiently.

This may help.

www.instructables.com

How to Tap a Hole

How to Tap a Hole: Tapping a hole is the process of creating threads on the sides of a drilled hole to enable screwing in a bolt or machine screw. This instructable will focus on primarily the use of taper taps, although there will be some mentioning of bottoming taps…
www.instructables.com www.instructables.com
 
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So when you offer up the new handle but without screwing it in, the spindle turns the mechanism and it operates all ok? So you basically just need a method to securely mount (bolt in place) the two kind if guide bolts or machine screws presumably?

If I have understood correctly then, the new bolts have ok threads, you just want to match this by tapping new ones into the window internals. So what you want to look out for is something called pitch. This describes the type of thread. It would need to match the pitch of the bolts on the handle. If that is not listed in the specs of the handle, you can buy a cheapish device which I think can measure thread pitch. Or you may be able to physically measure it with a ruler and by eye balling it. Not sure on that though.

Then you can try to tap new threads. Or.... can you not just do what people do sometimes with mounting TVs and use some powerful expoxy resin stuff and just literally sink the handle bolts into it and clamp it in place to set permanently? I've seen people mount TVs in that was sinking long threaded bar into a wall.
 
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To be honest if your a super noob at diy

I may be tempted to try a few hacks first.
If the supplied bolts/screws are the correct size but not quite connecting due to old wear, you can wrap the new ones in ptfe tape and that will often be enough to get them to hold
or electrical tape which is thicker.
If the thread is almost good enough this sort of thing will often just pack it enough to get it to hold.

The next hack up so to speak is to use a metal putty. Get a bit into the hole, wind a bolt/screw in and then out and leave it to set.

The other option again if its close is that threadlocker may work, eg

As jaybee mentions above you could go for a permanent fix, either metal putty, or superglue or resin. But if something goes wrong here its likely be more of a problem next time!
 
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jaybee said:
So when you offer up the new handle but without screwing it in, the spindle turns the mechanism and it operates all ok? So you basically just need a method to securely mount (bolt in place) the two kind if guide bolts or machine screws presumably?

If I have understood correctly then, the new bolts have ok threads, you just want to match this by tapping new ones into the window internals. So what you want to look out for is something called pitch. This describes the type of thread. It would need to match the pitch of the bolts on the handle. If that is not listed in the specs of the handle, you can buy a cheapish device which I think can measure thread pitch. Or you may be able to physically measure it with a ruler and by eye balling it. Not sure on that though.

Then you can try to tap new threads. Or.... can you not just do what people do sometimes with mounting TVs and use some powerful expoxy resin stuff and just literally sink the handle bolts into it and clamp it in place to set permanently? I've seen people mount TVs in that was sinking long threaded bar into a wall.
Click to expand...

Not quite, no. The replacement handle is just a bog standard cockspur type handle (I linked to it in my OP) that I'm trying to attach to the window frame. The problem is none of holes are suitable as they're completely stripped and warped.

I'll have a look at epoxy resin and see if that might work better than using the metal stuff.

Mercenary Keyboard Warrior said:
To be honest if your a super noob at diy

I may be tempted to try a few hacks first.
If the supplied bolts/screws are the correct size but not quite connecting due to old wear, you can wrap the new ones in ptfe tape and that will often be enough to get them to hold
or electrical tape which is thicker.
If the thread is almost good enough this sort of thing will often just pack it enough to get it to hold.

The next hack up so to speak is to use a metal putty. Get a bit into the hole, wind a bolt/screw in and then out and leave it to set.

The other option again if its close is that threadlocker may work, eg

As jaybee mentions above you could go for a permanent fix, either metal putty, or superglue or resin. But if something goes wrong here its likely be more of a problem next time!
Click to expand...

The holes are completely stripped so I dont think the PTFE tape will be enough, there's just nothing left for the screws to bite on to.

My current plan is just to pack the holes/cavity with metal putty (i linked to it in my OP) and then create new holes but i'll have a look at using resin instead as that might be easier to work with.
 
the new handle door plate is long enough to overlap the 4 degraded holes ?
otherwise I might bolt the handle onto a thin shim of stainless steel , that extends to the location of some new holes you drill in the frame
e2: 1mm would be fine

e: or if you can expand any of the 4 holes into a slot, where you can introduce a bolt head, and drill a matching hole in the handle plate, with nutsbolts on the outside
 
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Doobedoo said:
You maybe better off using a rivnut. Drill the hole out to the appropriate size then use the rivnut gun to fasten a permanent fixing. Assuming you have metric screws to fasten the handle to the window.


Click to expand...

Well holy mother.... mind blown. I have a pop rivet gun but did not know these things existed. Pretty sick tool.
 
jaybee said:
Well holy mother.... mind blown. I have a pop rivet gun but did not know these things existed. Pretty sick tool.
Click to expand...
Rivnut is just a dodgy version of a helicoil :D
(In this instance)
 
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jaybee said:
Quick, find a need for a threaded insert in some metal to justify...

Then be smug when in 6 years time your mate/Dad needs a job doing which warrants use of the tool which totally made it worthwhile.
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He he I could probably have used them on my old greenhouse before the storm wrecked it a few years back
Look at them I am pretty certain some of the items I have put together have used them since they look just like the threaded inserts you sometimes get in eg metal self build garden furniture
 
jaybee said:
Well holy mother.... mind blown. I have a pop rivet gun but did not know these things existed. Pretty sick tool.
Click to expand...
I have a helicoil kit in my van but haven’t needed to buy my own rivnut kit. We have one in the workshop but the stuff I work with usually only requires tapping a new thread.
 
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