holes for tapping

[stoatyboy]

assuming a home made router lift is a jig I hope i'm in the right place!

to make the above I need to put a thread in a hole - which is already very conveniently in the right place for it in the router

if the hole is 8mm (which it is) what size tap would I need to make the smallest threaded hole available? does that make sense?

I don't want to make the hole any bigger (apart from what I have to remove to cut the thread of course).

the hole is the hole that the depth stop slides up and down in - in case you wondered - and made of alloy - so easy to cut. and I don't mind voiding my warranty as the router cost a fiver at a boot sale on Sunday.

had a look at some charts on a techy web site that suggested an 8.5mm hole would enable an M10 thread - sound about right?

as ever thanks for any help

Pete

 

[CHJ]

8.5 mm is correct tapping drill size for 10mm ISO Coarse thread.(the common one in use)

http://www.gewinde-normen.de/en/iso-coarse-thread.html

 

[jasonB]

3/8"x16 UNC will not require the hole enlarging as 8.0mm is tapping size.

3/8"x20 BSF requires 8.3mm

3/8"x24 UNF requires 8.5mm

M9 x 1.0 metric fine requires 8.0mm but you would have a job finding screws to suit.

Jason

 

[monkeybiter]

I would think you'll probably get away without enlarging the hole, as it's the non-ferrous alloy you're tapping. If you're leaving the springs on you could probably bond an M8 nut on the side opposite the base.

 

[stoatyboy]

You guys are good!

loads of great ideas thanks - I'm kind of keen to tap the hole as it feels like a 'slicker' solution

but glueing an M8 nut on might be easier!

as with all my builds it's likely to be a long one i'll try and do some pics when complete

thanks again

Pete

 

[flounder]

as with all my builds it's likely to be a long one i'll try and do some pics when complete

When complete is all well and good, but it is 'work in progress' pics that we all love!! :wink:

 

[stoatyboy]

well what I meant was I'll take the WIP pics but post them when project complete to save the agony of the waiting!...

look out for it in the projects section :roll:

but don't hold your breath