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Bonnet fixings: DZUS or pull-down catches?
James - 3/3/06 at 10:40 AM

Would I be right in thinking the pull-down catches are functionally better as they pull the bonnet tight against the nose/scuttle?

Having said that, I am a little concerned where people have said that the pull-downs can pop open in warm weather.


The DZUS obviously aren't affected by the sunshine and have the advantage that they're smaller and maybe therefore look better but people have suggested they can come open too through vibration. Or is this just a result of them not being installed correctly ie. not tight enough against the spring?


Any alternatives to these two? I've seen the recessed catches in another thread but at £70 a pair that's a bit pricy!


Also, don't know if people leave their cars at all when they go out but has anyone looked at lockable bonnet catches of any sort?


Cheers,
James




[Edited on 3/3/06 by James]


Fozzie - 3/3/06 at 10:45 AM

James, I have had no problems with my 'pull down' catches, and its been on t'road for nearly 2 years now. Its all about getting the tension right. I can't say as though I have left the car out of my sight, so I have not considered the lock, but I am sure we can come up with something!
Fozz


Bluemoon - 3/3/06 at 10:46 AM

I'm favouring DZUS at the moment, after all they are designed to hold outer pannels on 1930's aircraft.. Should'nt be a problem for SVA as they are nearly flush fitting.

I think if you install them correctly (a pain apparently) then they should be ok. The self ejecting EHF(?) ones are what you want as you don't have to "dimple" the panel. Also they pop out when un-done so it is obvous if they are unlocked.


Kissy - 3/3/06 at 10:46 AM

I seriously doubt a genuine Dzus, correctly selected and installed will come undone. They are use extensively on aircraft (hence the price) and there is no way they would be approved for use if there was any reasonable way they would undo. HTH


Hammerhead - 3/3/06 at 10:58 AM

regarding bonnet catches, is there any reason why builders cannot use the donors release mechanism?


smart51 - 3/3/06 at 10:59 AM

pull down catches are easier to open. I've havd to open the bonnet on my car more times than I'd hoped. I'd have got fed up with dzus fasteners long ago.


oliwb - 3/3/06 at 11:07 AM

Over centre catches with elastic bands to hold the SVA covers/stop them undoing......What I'm planning - not perfect but cheap and wont detract too much....Oli.


Humbug - 3/3/06 at 12:11 PM

My bonnet's been OK with the rubber SVA-compliant over centre catches... having said that, the car was registered in October so I don't know if there will be a problem in warm weather

I thought I could drill through the catch and the base and put in some R clips if necessary


stevebubs - 3/3/06 at 12:27 PM

Other options are:

Aerocatch - about £40
Westfield Lock & Pin Assembly - about £40


bob - 3/3/06 at 12:58 PM

James

My Dzus fasteners work fine but are a pain to fit and operate, when i change the bonnet i've got the rubber covered latch type from lolocost (cheapest price unless you get them free)


Mix - 3/3/06 at 05:34 PM

The big difference between the two fastening systems you mention is that the Dzus will not pull the sides of the bonnet downwards where as the over centre / rubber type catches will.
Therefore you need to be more accurate when fitting Dzus fasteners to ensure the bonet doesn't 'bulge' at the top.
If I were using Dzus I would fit them using slightly thinner packing material around the scuttle and nosecone than the finished seal, this will allow the seal to compress when the bonet is fitted and apply a bit of tension to it.

Hope that made sense

Mick

Oh! and yes, as stated above, a correctly fitted and fastened Dzus wil not come undone. The only failures I have ever seen with these fasteners have beeen due to the effects of vibration over a period of time fretting through either the 'spring' or the lugs on the fastener.


zetec - 4/3/06 at 09:03 AM

I started off with 4 Dzus fasteners but they are a real pain to fit, and one popped open on the front one day, now I know that is down to me not fitting right but once I started to not trust them I changed to over centre locking ones on the front. I ended up with some from Merlin which are adjustable and can take a "R" clip to lock them. At the rear I fitted Camlock panel catches, like Dzus but come with different heads and sizes to fit varying panel thichness. I fitted a pair with "D" shaped rings. No need to carry a screwdriver to take the bonnet off and totally secure.


tractorboy - 5/3/06 at 01:58 AM

i have used " cam locs" these are similar to dzus fasteners but they have a cammed recepticle that they lock into as apposed to a steel wire arrangement.i think deamon tweeks sell them . cheers scott