imperial threads

[busdennis]

ive caused some damage today by tring to tap an imperial thread with a metric tap and since learnt they are many different threads and pitches

can anbody point me to a good reference page on the net and can my bodge be easily repaired

i damage some threads on a landrover engine by using a 12 x 1.75 tap since discovering the bolt is slightly too wide for a 12 x 1.75 metric nut

 

[rtbcomp]

This could be a good start:

http://mdmetric.com/thddata.htm#idx

 

[busdennis]

This could be a good start:

http://mdmetric.com/thddata.htm#idx

thats a great start. thanks
ive been told a lot of landrover stuff is unf but my bolt is 12.3mm diamater but i carnt match it up on their charts

 

[Simon-]

Possible that a Helicoil could remedy your situation?

 

[rtbcomp]

thats a great start. thanks
ive been told a lot of landrover stuff is unf but my bolt is 12.3mm diamater but i carnt match it up on their charts

Depends on the year.

Series III is a mixture of Unified and BSF. (BSF mostly on the axles). Metric found their way onto the later SIII's on the 5 bearing petrol engine and general nut & bolt positions.

Which the bolt you're having trouble with?

 

[busdennis]

Depends on the year.

Series III is a mixture of Unified and BSF. (BSF mostly on the axles). Metric found their way onto the later SIII's on the 5 bearing petrol engine and general nut & bolt positions.

Which the bolt you're having trouble with?

the landy is based on a series 2a but it has a 19j engine from a defender
the bolt is the adapter on the lucas fuel pump that joins the pump to the return fuel line to the filter

 

[madkayaker]

You can have bsf, unf, unc and metric on a landy! Get a set of thread gauges and a reference book.

 

[piman]

Hello Dennis,

buy yourself one of these, Zeus Tables :-http://www.amazon.co.uk/zeus-tables/s?ie=UTF8&keywords=zeus%20tables&rh=i%3Aaps%2Ck%3Azeus%20tables&page=1 Amazon is just an example, many others sell them. i think I even got mine from Smith's.

Fuel injection equipment may also be BSP

Alec

 

[brightspark]

thread chart

 

[Robotstar5]

the landy is based on a series 2a but it has a 19j engine from a defender

I thought 19j was fitted to 90/110 and 200Tdi by the time they changed to Defender?

 

[rtcosic]

You can have bsf, unf, unc and metric on a landy! Get a set of thread gauges and a reference book.

I'm fairly sure I came across a Whitworth on the gearbox or trans box or overdrive.

 

[naughtyboy]

where abouts are you?
got sets of t-gauges you can use and prob got right bits as box upon box of bits from landys.

 

[madkayaker]

1/4whit is the same as 1/4unc well they will fit together! Same as 0ba is 6mm

 

[langy]

I think you will find what you thought was Whit is actually UNC, On first inspection they appear the same but in reality they are not.

I'm fairly sure I came across a Whitworth on the gearbox or trans box or overdrive.

 

[jugs]

1/4whit is the same as 1/4unc well they will fit together! Same as 0ba is 6mm

Whit is 55° UNC is 60° so although they will go together if you tighten them up the contact line is so small the threads distort, such a combination only has about 25% strength of proper nut & bolt.

BA =47½°, mm = 60° so that has less contact area - think 10% of strength

 

[Pete.]

The Landrover was invented by a guy local to you wasn't it Jugs?

 

[gordon stephenson]

The bolt you measured at 12.3mm will be actually imperial 1/2" which is 12.7mm dia,

 

[jugs]

The Landrover was invented by a guy local to you wasn't it Jugs?

Yup,
HERE'S A LOCAL LINK

I have to confess I didn't know that , so thanks to you & google

 

[awemawson]

The bolt you measured at 12.3mm will be actually imperial 1/2" which is 12.4mm dia,

12.7 actually !!!!!!!!

 

[gordon stephenson]

Yes, Sorry about that chaps,Fingers moving faster than the brain again, I'v corrected it now,I had the inch conversion on my mind which as you know ends with a 4, Freudian slip,