adamlewis

If I want to tap a hole to accept a 14mmX1.5 sensor, what do I need to call around and ask for? I understand I need a 14mm drill bit too?

Im so confused...

1SxyRXy

u will need a tap. its actually not that hard. just drill the hole the size u need it then thread it

Hot_Dog

If you're planning on cutting 14 mm internal threads, than you don't want to use a 14 mm drill bit because you won't have metal left to cut into. As a rule of thumb, when cutting internal threads, the hole size should be the major thread diameter minus one over the pitch. Simply put, 14 - 1/1.5 = 13.333 mm (or 0.525 inch) should be the approximate size of the drill bit. There are machinist's charts available that give the required hole size for a specific tap.

Hot_Dog
90 RX7 GXL
02 Acura RSX-S

Derek 357i

Here is the tap chart I use

http://www.carbidedepot.com/formulas-tap-metric.htm

HAILERS

Thanks for the drill chart. Bookmarked.

CarmonColvin

Check out www.mcmastercarr.com

Browse to page 2220 in their catalog.
They suggest a drill size of 12.5 for a 14x1.5mm tap.

I bought the taps required for a rebuild from them. Excellent customer service and fast delivery.

Kyrasis6

Here is the one on Solomiata, personally I don't like it there are better ones out there, I'm posting it just for another reference.

http://members.aol.com/solomiata/tapdrillchart.jpg

adamlewis

Ok...What size drill bit would I need for a 3/8 NPT tap?

banzaitoyota

37/64

adamlewis

And exactly how did you figure that out?



Thanks BTW

banzaitoyota

I have a decimal equivlant and Tap dRill size Chart in my Cubicle. When that fails I reference Machinery's Handbook.