Model Engine Maker

Supporting => Tooling & Machines => Topic started by: Tjark on February 08, 2019, 12:59:32 PM

Title: What drill do i have to use?
Post by: Tjark on February 08, 2019, 12:59:32 PM
I have bought a ľ x 32 spark plug and tap for the treading.
Now I wonder witch drill I have to use for the tread hole.
I have surged on the net but I canít find this information.

    Tjark.
Title: Re: What drill do i have to use?
Post by: Jasonb on February 08, 2019, 01:04:27 PM
5.7mm will do you for UNEF

https://www.gewinde-normen.de/en/unified-extra-fine-thread.html
Title: Re: What drill do i have to use?
Post by: Tjark on February 08, 2019, 01:51:29 PM
Jason, thanks for the information.
Also thanks for the list, I never heard of UNEF tread.

    Tjark.
Title: Re: What drill do i have to use?
Post by: Lew Hartswick on February 08, 2019, 06:59:19 PM
A 1/4 - 32 thread is usually (for a 70% thread)  1/4" - 1/32" or  7/32"   :-)   Just like all the "Metricanized" folks do. :-)
   ...lew...
Title: Re: What drill do i have to use?
Post by: steamer on February 08, 2019, 09:47:21 PM
Jason, thanks for the information.
Also thanks for the list, I never heard of UNEF tread.

    Tjark.

Get ye a machinery handbook.    8)

https://www.amazon.com/s?k=Machinery+Handbook&ref=nb_sb_noss_2

Otherwise known as the "Good book"  If you're going to do this stuff, it's really a need to have, as it's got so much information in it.

Unified National Extra Fine.   by the way

Dave