If i'm honest, I never needed to know what a tap and dye set was for until I buggered up my top seat belt anchor. I bought a 40 piece kit, only to discover that the size I want is not there.

Just to be sure before I order a separate piece, am I correct that I will need size M12 x 1.25 tapered? Thanks.

Worth investing in one of these imo, quite handy and only cheap http://www.axminster.co.uk/metric-imperial-thread-pitch-gauge-900472?gclid=Cj0KEQjw4827BRDJvpbVuKvx-rIBEiQA2_CzsFuITpX1-dI1Oeb9_lAPLeouk67kg9ZxLDn2hBF9I2IaAho58P8HAQ

 

How are you repairing it? If you've stripped the thread, what use is the standard size tap? Surely you need to go a size up?

I've stripped or bent the threads right at the beginning which skews the bolt to an angle. That device I have which says 1.25 but when ordering I have all sorts of options...I'm leaning towards tapered. When you say a size up, do you mean I can recut what I have if I use say a 1.5 on it? Didn't know you could do that...

 

Sent from my VG30DETT

No not quite, 1.25 or 1.5 is the thread pitch, the distance between the peaks of the thread. I think the smaller the pitch the more torque it will take so probably don't want to go up a pitch size. I meant go up a bolt size, so from 12mm to 14mm for instance. You would have to drill out the existing thread/hole to the right size (not sure if that would be 14mm, may have to go smaller) so you get rid of the old thread, then you can tap the new hole fresh. This would obviously require a new bolt!

 

Not sure if that's a goer now really when I think about it. Taps tend to be an inch or two long and you need to turn them in right to the bottom, normally. Not sure there's enough room behind the hole for that?

 

If you've only damaged the beginning though, you may get away with just redoing that bit I suppose. Maybe only getting the tip of the tap in will be enough.

 

Whether either of these options is safe on a seatbelt mount is up to you! Personally, I'd not be too worried about doing either one but it's your neck on the line :clover:

 

There is a third option though I suppose...

Here you go, could use a helicoil

 

http://www.stanleyengineeredfastening.com/brands/heli-coil/screw-thread-inserts

 

My old man repaired a stripped glow plug thread with it and that held up fine so I think in theory they're pretty strong. Again, whether they're suitable for a seat belt though is up to you to decide!

Ah think I just twigged what the taper means, thought it sounded odd. Think they're talking about the tap, not the bolt!

 

"Q: What is the difference between taper, plug and bottom taps?

 

A: Taper taps are often called "starting" taps because they have more chamfered threads. Chamfer is the angled portion at the front of the tap which helps it start threading. Taper taps have 7 to 10 threads of chamfer. Plug taps have 3-5 threads of chamfer, bottoming taps have 1-1-1/2 threads of chamfer"

 

"Q: Why use a bottom tap?

 

A: To tap the bottom of a blind hole."

 

Means it doesn't bite in fully straight away like a straight tap would. In this case, I would guess you want a straight tap or even a bottom tap as it's the tip you'll be using as I previously said

Edited June 29, 20169 yr by Chris

Here you go, could use a helicoil

 

http://www.stanleyengineeredfastening.com/brands/heli-coil/screw-thread-inserts

 

My old man repaired a stripped glow plug thread with it and that held up fine so I think in theory they're pretty strong. Again, whether they're suitable for a seat belt though is up to you to decide!

 

LOL, I was just watching a heli coil demo on You Tube.

I think I'll try the tapered 12x 1.25 first, followed by Heli- Coil method second.

Thanks for a speedy reply all:thumbup::thumbup:

That's two new things I've learned today

LOL, I was just watching a heli coil demo on You Tube.

I think I'll try the tapered 12x 1.25 first, followed by Heli- Coil method second.

Thanks for a speedy reply all:thumbup::thumbup:

That's two new things I've learned today

 

May want to reread my last post, just edited it!

Just did, thanks for the explanation. I'll order a bottom tap.

Just did, thanks for the explanation. I'll order a bottom tap.

 

Yea that or plug, hard to know which is going to be better. If there's a decent amount of room behind the hole I'd go with a plug tap. 3-5mm at 1.25 pitch would be 4-6mm of space to get to the main part of the tap so putting it that way there is almost certainly enough room for a plug tap surely!?

Tap worked a treat! Thanks for all advice..

 

Sent from my VG30DETT