I strap no small amount of $$$ to my roof, and would be devo if they flew off, so I tend to give the tie-downs a bit of 'downhaul'.
They get a fair amount of tension so they can handle 140kph (hypothetically *ahem*) down the freeway.
Suspect that might not be awesome for my boards, but they won't fit inside the cabin. Am I damaging them in someway? What do you do?
I have foam rack padding to absorb any extra stress on the board and only tie the boards on hand-tight. Board-bags are also good for this purpose. Too much tension will damage the boards.
As long as you only hand tighten the straps and don't have the buckles where they could press on the edge of the board the board should be OK.
Don't use a ratchet style of tightener. They can crush boards.
Use these: www.kanulock.com/
Soft and wide. Also lockable so someone can't steal your gear. Best straps ever. Also put foam underneath board on top of racks as suggested above.
Cheers
Marty
I pull a bit a tension on the tie downs but don't go crazy with it, I also always knot the tie downs at the buckle. My boards have been just about 18 months full time on my roof rack with no dramas, as I do the grey nomad thing.
Martin I think I'll grab a couple of those 
Okay, so maybe I won't lock 'em down so hard. They've already got some padding - both boards in bags, and the top of my racks have rubber grip. But I'll look for a touch more padding as suggested.
Where I sail theft ain't a problem, so I don't need locks, just something I can trust, and simple/quick to operate. I've have owned a series of the FCS' for a good ten years - super happy with them.
Wide, strong straps and a real easy locking mechanism that has no moving parts to break. Rock solid. They're not ratchet, but if I put my weight behind it, I can get a lot of tension.
http://www.surfsailaustralia.com.au/showProduct/Racks/Tie+Downs/399122/FCS+Premium+Tie+Down+Straps
Select to expand quotePhilSWR said..
BEWARE of going two boards wide with the clamp style racks.
Kanulocks are good.
Clamp style racks can turn into IFO's. Board, racks and sunshade in one bundle but the Kanlocks will keep them all together. 
Kanulocks are a very good investment. I've had mine for a couple of years now. They have 2 s/steel cables that run through them and although the locks are fairly basic, they work well.
Select to expand quotehargs said..
Nah, they'd give up trying to cut thru the Kanulocks and just steal the whole car and kit with it lol!
I know someone that uses Kanulocks... lost his boards, when they cut through the cables with a bolt-cutter.
The first time it happened, they turned up at the local pawn shop.
Select to expand quotemathew said..hargs said..
Nah, they'd give up trying to cut thru the Kanulocks and just steal the whole car and kit with it lol!
I know someone that uses Kanulocks... lost his boards, when they cut through the cables with a bolt-cutter.
The first time it happened, they turned up at the local pawn shop.
Of course if someone is determined they will take anything. The straps are only going to keep away an opportunistic thief with a knife to cut through normal straps. It's better than nothing and they are also wide, padded, don't vibrate in the breeze and simple to use without crushing the rail on your board. What is sad that we have to take such extreme measures to protect ourselves from these scum.
Cheers
Marty
Select to expand quoteImax said...
I find over 180km ph its best to leave the fin on for directional stability
Not in an IMax! 
My first experience with flying objects 
The bag can be strapped down, however care is needed to find a loop or handle to put the tie down straps through. You may find the bag can work its way out backwards.
No a pretty picture a pensioner running down the Bruce highway diverting traffic so that his new carbon board doesn't get run over
A hard won horrowing lesson in the use of roof racks
Cheers Jeff
