Derby Cover & License Plate Holder

[Brigg]

Need some guidance re: Drill Bits..

Ive been trying for the last couple weeks to drill out the screws that attach the derby cover and license plate holder (awkward to get at).

So far all the drill bits I've purchased have been crap, the last a set of Makita HSS bits.

I have drilled out the 'slots' of the screw heads but cant seem to penetrate down to drill out the head.

Any ideas on quality drill bits... if not its case of independant or stealer at £50.00 to £95.00 per hour...

[girlyglide]

Originally Posted by Brigg

if not its case of independant or stealer at £50.00 to £95.00 per hour...

Thanks for that, I'll put my labour rate up to meet your expectations.

[English Steve]

'Dormer' are probably one of the best you can get, although even their quality isn't what it used to be (cue for a song). Cobalt tipped ones are also good.

It is possible that you have hardened the screw by having the drill bit spinning without cutting, and generating heat. If that is the case you will need a good quality, sharp drill bit and use it with a firm pressure and medium to low speed. Not easy with a pistol drill when you're working positionally, and please don't slip

[Brigg]

Originally Posted by girlyglide

Thanks for that, I'll put my labour rate up to meet your expectations.

lol... My Sportster died about a month nr Betws y Coed... The nearest dealership was Chester, so had it relayed there.

It turned out that water ingressed through the wiring loom and into the fuse and relay 'box' and corroded out some of the fuses.

This cost me labour £178.00
Consumables £ 3.50
+15% £208.73

So basically £181.50 for a clean up of the fuse box and drop of dielectic grease...

Turns out this is a recognised fault on 07 Sportsters and covered with HD TT322 another club member Phil provided the tech sheet.

So hopefully I should get my money back via a warranty claim...

[Limey_Dave]

I suspect you may have started with too large a bit,with a 1/4" derby cover screw you only need around 3mm,this would have hopefuly left enough slot to pop the heads off and leave some "trunk" to remove the screw.
The screws are Grade 8 so quite hard to start with but a Dormer,Osbourne,etc drill idealy tin coated and ground flute.
The Makita although HSS was prob a Jobber Drill that are disposable and not the best for accurate work.
If you use 3mm you need min speed of 1100 RPM but main thing is to keep it cutting not rubbing.

[Hawkeye]

Originally Posted by Limey_Dave

I suspect you may have started with too large a bit,with a 1/4" derby cover screw you only need around 3mm,this would have hopefuly left enough slot to pop the heads off and leave some "trunk" to remove the screw.
The screws are Grade 8 so quite hard to start with but a Dormer,Osbourne,etc drill idealy tin coated and ground flute.
The Makita although HSS was prob a Jobber Drill that are disposable and not the best for accurate work.
If you use 3mm you need min speed of 1100 RPM but main thing is to keep it cutting not rubbing.

If you have a second pair of hands fill a squeeze bottle with water and just dribble it on the cutting area. Should be coolant but water is better than nothing at all.

[spinlondon]

Sounds like you have over heated the srews causing them to become hardened.
You need to get some Cobalt drills preferably left handed ones.
Snap On do a set of 5 varying sizes, and can be obtained via a Snap On dealer van or via their website.
I say left handed because sometimes when drilling out snapped bolts etc. the drill will catch the fastner and draw it out.

[Kiwi]

and when you get them out replace them with stainless allen heads with copperslip on the threads, to eliminate this happening in the future

[Rubianroaddog]

Personally for this sort of task I would use TiCN coated drill, but I would grind the point to 90 degrees not the usual 118, this will give better centering and a slower actual cut. As with all things a bit of lubrication always help, WD40 is great, and I love the smell when it is burning.

Additionally V twins tend to shed bolts faster than a persian cat sheds hair, so copperslip on the threads may cause these to disappear.

Cheers
Mick

[Brigg]

Thanks for all the tips and advice.... hopefully will get this sorted during the week....