brewsky wrote:"DING" We Have a Winner!!brewsky wrote:The pitch is the same, it is the head dimensions that are different.
I pulled up the specs on the two screws I used in my example above and for the 6x20 1mm pitch Pan Head the DIN Head Diameter is 12mm, Head Height is 4.6mm, and a #3 bit is used in the head. The JIS Head Diameter is 10.5mm, Height is 3.9mm and it also uses a #3. The part I still don't understand is the cost. DIN: $9.25 per 100, JIS: $10.15 per 25. You would think that all other things being equal, the DIN with the larger head would be the higher cost.
So the JIS with the smaller head is what I'll order for the smaller screws (head side covers and such) and I think I'll go with the threaded rod and acorn nuts for the case screws because as it was pointed out that partially threaded machine screws are a bit tougher to find, and I like the idea of acorn nuts both for the looks and for the ease of removal.
And... as e3steve pointed out, ISO is correct for us in the 6 & 8 size. But... does ISO = JIS or DIN ? :-) Hmmm
Thanks to all that responded.
George
6mm Screws... DIN or JIS ??
As I mentioned earlier the real difference in a 6*1.00 is that JIS is 55 degree thread angle and ISO is 60 degrees.
The extra cost is probably set up and stocking costs for a thread angle that's non standard (it's the old BSP angle IIRC) If hardware store bolts work, then it's regular ISO threads - Not JIS that you want.
The hardware store bought screws -did not- say ISO or JIS or anything other than 6mmxLength 1mm pitch. So if that means the store bought screws -are- ISO, and ISO is -not- the same as these JIS, and these JIS -are- the same as these DIN (except for the head size) then -neither- of the two choices I have above are correct? I measured the pitch on the store bought 6mm screws and the 6mm case screws at 1mm, and both 6mm screws I refer to above are listed as 1mm pitch. So again, as -teazer- is saying, neither the JIS or DIN is correct? ISO - JIS - DIN - Boy now I'm really confused!! I'm sure all you folks know what your talking about, it's just that I'm having a real hard time following.... Maybe I just need more coffee :-) Or maybe it's best to just let this thread die out for now. tnx George Present JIS and ISO should be the same specs.
6mm screws, 1.0 pitch, 60 degree thread angle. DIN should be the same as above, except screw head size a little different. I believe the 55 degree spec is for pipe threads. Any readily available metric 6mm should fit. Not the case with 3,4,5 or 12mm however. 66 dream, 78 cb750k, 02fz1, 09 wing
You guys think you have problems? My main yacht, on which I'm refit electronics engineer each year, designed by Italian Luca Brenta for Wally Yachts -- also an Italian company -- but was built at the Concordia Yachts yard in MA.
The yacht lives between Oslo (Norway) and St Tropez (France), but we usually refit in Palma (Spain), but sometimes at Pendennis in Falmouth (Cornwall, England). We use ISO screws. The world uses ISO screws. The yacht was built using bloody NC screws! The hydraulics' systems were put together using NPT; the world uses BSP (otherwise known as 'pipe' thread). She's fifteen years since launch, now. She used to exude a constant fog of atomised hydraulic oil within the interior, the result of >400bar systems, and the bilges always held a goodly level of oily seawater in reserve, ready to catch the next poor, unsuspecting soul to lift the sole. It's been an ongoing battle, but we're getting there. The leaks are less, if not eradicated (apart from the odd burst flexi hose). The replacement unions are of 'pipe' thread; the NPT stuff is all but gone. No leaks.
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