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johnbaz

Cheap taps/dies :( :(

Hi all

A mate at work has acquired a minit (or Midi!) moto that someone has Beggared up!!

They've stripped the threads on one the cylinder head boltholes..

To make it worse, they drilled out the hole to retap it and went too large with the drill foe an 8mm bolt (original was 6mm head bolt)..

Anyhow my mate asked if I could make a screw in sleeve from a 10mm bolt, easy peasy thinks I  

It seems that the tap/die set that I bought from Lidl (or Aldi, can't remember which!!) wasn't all it was cracked up to be    

Here's the result!!



I think they're carbon steel rather than Hss, OK for holes up to 1/2" deep but after that it struggled like mad! (to be fair, it was a high tensile bolt    It struggled all the way through, i'd centre drilled the bolt in my lathe to a depth of around 30mm with a 5mm drill then run the tap down, it cut well for the first 12/13mm then struggled the rest of the way!!, The sleeve was to be 20mm long but the tap failed just as I was reaching the 20mm  

Never mind I had a spare 6mm tap, thias time armed with mild steel 10mm threaded rod, easy peasy thinks me!!

CRACK!!, that one failed too as it was coming up to the 20mm of thread mark  

I had some high quality taps in Hss but they got left in the shed in a babymilk tin, the roof leaked and the taps were dead rusty when I found them but as a last resort I went through them and found two 6mm taps, I cleaned the rust off them with a rotary wire brush and one came out like new!!

tapping with this one was a breeze!!, It was cutting great and smoothly and wasn't twisting like the cheapos!!

Finally done with a 'Proper' old English tap  




It took all of ten minutes with the proper gear- there's no substitute for quality tools  



CHeers, John   [/img]
12Bore

Nice job, especially after the PITA bit!
magnet

Those chad valley taps aren,t worth a damn give me a Dormer every time ................Magnet
sod

Great job, took me a while to catch on that for real jobs cheap gear aint worth having. That is a real good looking job.
Yorkshire Geordie

Buy cheaply, pay twice.  
Martyn

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