Manky Monkey Motors

Technical Section => General Tech => Topic started by: Olds on November 06, 2018, 12:52:46 PM



Title: Cross point screws. Work of the devil.
Post by: Olds on November 06, 2018, 12:52:46 PM
Marcus (Lunatic) recently located a hardtop for my MX5 in near new condition.  ;D
Fitted perfectly but I had a problem with one of the rear deck catches. The covers are held in place by small cross point countersunk screws. One came out no sweat, the other was a real pain.
 This little M4 screw took over 4 hours, a lot of cussing, copious amounts of WD40, the making of a tool steel chisel, to cut a deep slot into it and the grinding of a screwdriver,  to remove. >:(
Needless to say it had to be replaced and while they are available from Mazda, at a very silly price no doubt, for just £1.29 I bought 10 stainless steel Allen head ones. Fitted with lots of grease, there shouldn't be any future problems. :)


Title: Re: Cross point screws. Work of the devil.
Post by: Manky Monkey on November 06, 2018, 01:54:36 PM
Always the small stuff that buggers up the plans isn't it! :)


Title: Re: Cross point screws. Work of the devil.
Post by: Olds on November 07, 2018, 07:30:45 AM
Yup. It's amazing how 'simple quick jobs' often end up taking hours instead of minutes, because of poor design or fasteners that wont unfasten.
 I have a particular loathing for cross points since working on Jap bikes in the 70's and 80's. There would always be at least one engine case screw where the head would be chewed up, need drilling out and you prayed that there would be enough shank left to grip after heating with a gas torch.
One Honda (CJ360t) sticks in my mind because someone had Loctited every fastener and despite using an impact screwdriver, all ended up being drilled.


Title: Re: Cross point screws. Work of the devil.
Post by: BikerGran on November 07, 2018, 11:35:09 AM
One of my enduring memories of my GT550 will be cross-point screws on carb tops!


Title: Re: Cross point screws. Work of the devil.
Post by: Bus Boy on February 04, 2019, 08:12:23 PM
Check out JIS screws on tinternet...............Japans own crosshead screw!!!


Title: Re: Cross point screws. Work of the devil.
Post by: Olds on February 06, 2019, 07:51:43 PM
Check out JIS screws on tinternet...............Japans own crosshead screw!!!
I know about JIS screws, as I worked for Honda motorcycle dealer in the early 70s. Look just like a Phillips but aren't quite the same. We used to warn customers to only use the screwdriver from the supplied tool kit.


Title: Re: Cross point screws. Work of the devil.
Post by: Bus Boy on February 06, 2019, 10:27:01 PM
only found out about them last year!!!!!!always late to the party me :-[


Title: Re: Cross point screws. Work of the devil.
Post by: Olds on February 07, 2019, 01:26:10 AM
Most folk don't know the difference. JIS cross points are usually marked with a tiny dimple or dot on the head.


Title: Re: Cross point screws. Work of the devil.
Post by: Bus Boy on February 07, 2019, 09:22:43 PM
see....I'm learning somthing new every day! :-[


Title: Re: Cross point screws. Work of the devil.
Post by: Tony oily bike on March 05, 2019, 09:40:25 AM
There’s a nice JIS (Japanese Industrial Standard) screwdriver available by a company called Vessel Megadora which looks like an ordinary screwdriver, but is in fact an impact driver.

A pal who runs a business selling used Japanese motorcycles has one and sings it praises.

Looks like they’re available for around the £20 mark.


Title: Re: Cross point screws. Work of the devil.
Post by: triker_Chewie on March 05, 2019, 11:13:17 AM
ive got one. its ace
only used it as an impact a few times but its does work
worth noting it only impacts "lefty loosey"


Title: Re: Cross point screws. Work of the devil.
Post by: Manky Monkey on March 05, 2019, 07:21:55 PM
Never seen one of those before -or maybe I have & just thought it was an ordinary screwdriver.