fairing and headlight

Looking for some guidance on best approach to cut the headlight hole on my Dunstal type half fairing? is there a trick to getting it right? I mean its not like you can cut the hole, miss and do her again....once the hole is cut what treatment is best of the fiberglass rim? Slice small diameter rubber hose in lieu of a proper gasket?

I did this for a friend many years ago…I just used a hole cutter, the kind where the blade can be adjusted in or out on sort of an "L," Like this one only larger - http://techno.com.my/online/images/ken5 ... _large.jpg

After the hole was cut I just smoothed/rounded the edges with wet/dry sandpaper and painted the fairing. Obviously if your fairing is already painted and you cut the hole, you will need to either try to paint the hole edges to match or, as you noted, use some sort of edge "covering." Small diameter hose could be slit to do that and would work fine. Also, I'm sure there must be something specifically made for that purpose though I have never used/looked for a specific product of that type.

I guess just find the centre of the headlight using an upright and square, transferring that to the fairing when its mounted. Here's mine but its on a PR fairing, pre molded of course...and not perfectly mounted as you can see. Diameter is 7". To clean up the hole why not just sand it. I'm sure a split piece of hose would be ok but is it needed? Hope this helps.

Here is a Dunstall fairing, been hanging high up on the wall in my shop for 25 years?? Don’t remember where it came from, never used.
This headlight opening has molded in flange. The headlight mounts in the fairing – note the three large adjusting/mounting screws. Also has a molded gauge panel (black) that bolts in too. Fairing is a nice piece, metal flake silver.
Could take it down and take a better photo to show where the headlight opening is, and take pix of backside too.

thanks every one, it is about as I expect, measure it three or four times, measure it again and let her rip.....

When I've got to locate a critical hole center, I just take my best guess and make a smaller hole like 2-3" in your case and then look in and locate the center of the headlight and cut the hole out to say 6". Then you can creep up on the perfect fit by trimming as needed to get the perfectly placed 7".
Jaydee

But my Ducati MHR has just a cut-out trimmed with vinyl edge molding (or moulding for you Brits). Just a round hole, headlight has clearance all around. Vinyl edge molding is available in different styles. Two screws in the photo are fairing mounting.

Floridia boys know fiberglass handling, ugh. Tape over gel coat face 1st. High speed fine teeth drimel bits or saber saws or copping saws to abraid rather than cut fg or splinters or grabs cutting tool. Fg hole saws have castle flat teeth with abraisive on faces. Drill are knobs with grit on them. A cable saw, ie: sharp textured wire with finger or dowel loops at ends does a pretty good hand control efficient slicing. I've use my various dia. chain saw files to open last bit of big holes for Peel running lights in thick wall fairing and finish small holes of gradually worked up regular drills applied with teeth gritting care. Might consider small ring of holes ~1/4" inside of final size then connect the dot and handle file or dremal grind to suit. Can also thicken up- back up back side of ring with good ole JBW and even custom mold back side of hole to conform nice to light fixure. JBW can also fix and find cracks and blems. I'm not good enough to hold a hole saw w/o tiny hang ups jerking it out of control. Various weather stripping home or auto or marine might be good to finish the hole edge.