10 replies to this topic

[Inno]

Hi there,

 

I am preparing for engine build and would like to prepare set of BSW taps to be able to clean all (or most of) threads on engine block, head and gearbox.

 

Is there a list of most important or most commonly used threads on 1275 engine/block/head/gearbow?

 

I planned to order something from ebay - I saw many taps from India and China - not sure about quality but also would not like to pay a fortune for thread cleaning tool....

 

Most sets includes: 3/16, 1/4, 5/16, 3/8, 7/16, 1/2..and 1/8 - also found something from UK for around 25-30 pounds.

 

Would those sizes cover main bolts/threads for engine rebuild?

 

What am I missing??

 

Thanks!

 

[alex-95]

The threads are UNC not BSW.

 

5/16 UNC is most of the threads that go into the gearbox and 3/8UNC ?(from memory) is the head studs. 

[nicklouse]

Ps running a tap down a threaded hole is not the best way of cleaning them as you are more likely just to cut more material away. Cut some slots in a suitable bolt and use that to clean out threads.

[Spider]

Best get Thread Restorers or Thread Chaser rather than Taps for that purpose.

 

You could buy a set, but most of it won't get used.

 

Common sizes are;-

 

1/4" UNF

5/16" UNF

5/16" UNC

3/8" UNF

3/8" UNC

7/16" UNF

 

Those will cover just about the whole engine and gearbox and about 95% of the car.

[DeadSquare]

Hi there,

 

I am preparing for engine build and would like to prepare set of BSW taps to be able to clean all (or most of) threads on engine block, head and gearbox.

 

Is there a list of most important or most commonly used threads on 1275 engine/block/head/gearbow?

 

I planned to order something from ebay - I saw many taps from India and China - not sure about quality but also would not like to pay a fortune for thread cleaning tool....

 

Most sets includes: 3/16, 1/4, 5/16, 3/8, 7/16, 1/2..and 1/8 - also found something from UK for around 25-30 pounds.

 

Would those sizes cover main bolts/threads for engine rebuild?

 

What am I missing??

 

Thanks!

 

As I once had a precision engineering business, I was asked by a friend, "what did I think of his set of cheap taps & dies".

 

They were actually not bad for dimensions, but his had been made with poor tools so that the surfaces weren't smooth and therefore cut a poor thread.

 

The 1/8th that you mention, for some reason is a BSP water/gas thread.

 

Nicklouse' advice is good. screw two nuts onto a High tensile screw of the desired size and lock them together.  Then drill down, between the nut and screw in three places with an 1/8th" or 3/16th" drill to make your own tap.

 

It won't tap a hole, even in aluminium, but iit will clean a thread;  so will  both the nuts.

[Inno]

The threads are UNC not BSW.

 

5/16 UNC is most of the threads that go into the gearbox and 3/8UNC ?(from memory) is the head studs. 

Thanks...I thought it is BSW.....UNC is a good news since I also have Harley (old one) and will be able to use same set!

[Inno]

Best get Thread Restorers or Thread Chaser rather than Taps for that purpose.

 

You could buy a set, but most of it won't get used.

 

Common sizes are;-

 

1/4" UNF

5/16" UNF

5/16" UNC

3/8" UNF

3/8" UNC

7/16" UNF

 

Those will cover just about the whole engine and gearbox and about 95% of the car.

thanks....so 2 standards at the end...will try to get a set Chasers

Edited by Inno, 12 May 2019 - 10:39 AM.

[Inno]

 

Hi there,

 

I am preparing for engine build and would like to prepare set of BSW taps to be able to clean all (or most of) threads on engine block, head and gearbox.

 

Is there a list of most important or most commonly used threads on 1275 engine/block/head/gearbow?

 

I planned to order something from ebay - I saw many taps from India and China - not sure about quality but also would not like to pay a fortune for thread cleaning tool....

 

Most sets includes: 3/16, 1/4, 5/16, 3/8, 7/16, 1/2..and 1/8 - also found something from UK for around 25-30 pounds.

 

Would those sizes cover main bolts/threads for engine rebuild?

 

What am I missing??

 

Thanks!

 

As I once had a precision engineering business, I was asked by a friend, "what did I think of his set of cheap taps & dies".

 

They were actually not bad for dimensions, but his had been made with poor tools so that the surfaces weren't smooth and therefore cut a poor thread.

 

The 1/8th that you mention, for some reason is a BSP water/gas thread.

 

Nicklouse' advice is good. screw two nuts onto a High tensile screw of the desired size and lock them together.  Then drill down, between the nut and screw in three places with an 1/8th" or 3/16th" drill to make your own tap.

 

It won't tap a hole, even in aluminium, but iit will clean a thread;  so will  both the nuts.

 

not exactly sure what you had in mind.......to take good quality screw as ARP and use it to clean threads?

I used 2 locked nuts technique to take old screws out of the block and head.

Do you suggest to use same but but carefully screw them in until they go easily?

[GraemeC]

I have a set of these, covers most eventualities in my garage:

https://www.amazon.c...5740111_TE_item

[Inno]

I have a set of these, covers most eventualities in my garage:

https://www.amazon.c...5740111_TE_item

thanks...will look in to it....didn't even know that for restoring and taping the thread there are different tools.

[Inno]

I have a set of these, covers most eventualities in my garage:

https://www.amazon.c...5740111_TE_item

I checked it out and it looks like it has all and more than I need (metric kit is a nice bonus).....just one question...are they all long enough for what I may need them?