how to replace trampoline rivets?

[lindsay s]

Hi guys

 

I am going to rerivet my trampoline tracks as they leak tremendously. Is there anything I should know before attempting this?

 

Also is there anything wrong or missing with my procedure?

 

1. drill out all the rivet heads taking care not to drill the track or glass.

2. remove the trampoline track, trying not to damage it.

3. clean up the bed. Remove what remains of the rivets, clean up rivet holes with epoxy.

4. coat the bed and holes with sikaflex (I'm not sure about this step. Is is necessary?)

5. lay the old track in the sikaflex, lining up the rivet holes

6. rivet with aluminium rivets

7. let dry for a few days

8. go sail

 

Thanks everyone.

 

Lindsay

 

 

[knobblyoldjimbo]

Looks like what I remember.  Just a couple of things:

1 make sure your rivets are large enough and long enough to pull from below rather than within the glass.  I think there's a strip of alum underneath the deck too so you need to go the other side of that.

2 if the track you speak of is the flat alum plate you might consider using caravan track.  this has a flat plate with a C section.  It means that the tramp is held by the alum rather than trying to lever up the plate.  On my cat (#16) it's been put in upside down so the C section is in the groove but apparently that makes it much harder to put the tramp on.  When I did it on a previous (but more recent) cat I put it C section upwards which is the most common.   As Rodney says this provides a hard point which is nasty if you kneel on it but otherwise it's better.

3 definitely sikaflex as it'll help hold the track but also seal up the rivets.  Use sealed rivets also if you can get them (or seal the holes with sika).

4. if you migrate to caravan track then you may need to use thicker bolt-rope - I think 7mm is the go.  On the one I did I used petrol pipe from a rubber shop and threaded/blew a line of 2 or 3mm prestretched chord.  I couldn't find an alternative.  I also had a cat with a Baracuta tramp.  The bolt rope on that was some sort of poly which was like a honeycomb, very rigid but worked really well.

5. use lots of washing up liquid as a lubricant - it'll wash away once you go sailing.

 

Hope this assists

[darcy1945]

 Have done the tramp track mod many times. Note! Punch out the old rivet stems before drilling otherwise the drill will run of the steel stems and enlarge the holes, Reuse of the flat track is a waste of time, use caravan annex track from Bunnings. My ph 02 43591729 for advice on Mari repairs.

[lindsay s]

Hi guys

 

Thanks for the advice everyone, I am a bit confused about the caravan track though.what are the advantages of using caravan tracks over reusing the original system?

And will the trampoline have to be modified to fit the caravan track?

 

Cheers 

Lindsay Small

Maricat 719, Twice as Nice

 

 

[Pointed Reply]

Darcy likes caravan track.

It is stronger, maybe easier and maybe more reliable but....... it is ugly and creates a hard point.

It is very possible to repair using the original. Unless very worn then you won't need to replace the bolt rope. If it is that worn then your tramp may be worn also.

Be careful about using any permenant filler or glue on the tramp track as you will need to take out the tramp again at some time.

As Darcy says tap out the old rivets they will roll down to the bung hole.

Make sure you clean out the slot very well. Remove any high point around the rivet holes especially is you have added some resin to the holes. Getting a proper grip by the flat plate requires a very flat snug fit onto the deck under the plate. If the gel coat is very worn on the inner edge then you may need to drizzle on then sand off some resin along the inner edge.

Test by gently blowing up the bungs and mist on soapy water.

Once reattached, start feeding the tramp on from both sides from the bow, work slowly each side. A friend on the other side will help. As Jim says detergent may help. Put as tight as possible.

Yes using the original flat plate may be fussier but in the end you will get a better looking job.

Good luck

[Aqua Rodent]

Mount the bunnings caravan track with the flat side up to avoid the ugly lump - ends up looking almost identical to the flat strap.  The extrusion also has nice bevels on the underside which arguably look better than the alloy strap.  The proper track moulding will be kinder on the bolt rope of the tramp and if the rope is sized correctly and not just cheap poly silver rope, it will never pull out.  For extra bling factor, you can even use 5mm fibreglass rod instead of rope to hold the tramp in.

 

Fasten with stainless self tappers, and if you drill your holes the correct size pilots into the aluminium plate, you will never have them come loose but will be able to remove and reuse them if you ever want to take them off.

[MrBean]

Hi Aqua Rodent.

 

Having recently purchased a Mk 1 in need of some TLC, I am going through this very same process. I assume what is being referred to as 'caravan track' is what is labelled in my local Bunnings as 'Sail Track' of dimensions 27.95 x 12.7 x 1.7 mm?

 

I plan to mount inverted, as suggested, to avoid the hard point. I would also prefer to secure using stainless self-tappers rather than rivets so that the track is more easily de-mountable in future should the need arise.

 

I note Darcy recommends using 3/4 inch rivets to ensure these pass through the alloy strip moulded into the hull. I assume 3/4 inch self-tappers will also be required for the same reason?

[knobblyoldjimbo]

Having just been trying to remove the s/s screws from the transom pintles I'd recommend against using s/s into aluminium.  All that will happen is that they'll seize and make removing them (object of the exercise) impossible resulting in a difficult drilling operation.

 

Now, Rohan, can you do a pink tramp like Mick's go fast Taipan one.  I think it's very sexy and clearly so attractive that Mark TBoned him to get closer!

[Aqua Rodent]

Jimbo - have you heard of Duralac?  Anytime dissimilar metals are in contact it's imperative if you ever want to remove them again.  I thought everyones boat toolbox had the green shit spilt on it!

[MrBean]

There is an alternative to Duralac called Tef-Gel. Was recommended by my local chandler in preference to Duralac for the following reasons:

 

1) It doesn't go off in the tube

2) is less expensive than Duralac

3) You can buy a smaller quantity (as little as a 10g tube)

 

See www.tefgel.com.au

 

Mind you, on the packaging is does say 'resistant to' salt water and detergents which does not imply it is 'totally' resistant. However, a graphic does show it being used on the prop shaft of an outboard motor.

 

Having bought some I guess I will let you all know in a couple of years!