Fibreglass or Alloy Canopy?

Interesting point about galvanic corrosion, will have to check into this.The alloy unit I looked at has a skin on ribs but I don't know what material it is. If this corrosion is an issue, wouldn't all alloy trays have the problem as it is bolted onto steel chassis?

Wok,

To date, I agree with you on this one. My aluminium tray was attached to galvanised steel runners without apparent ill-effect. I have fitted galvanised steel components to aluminium, but usually with a layer of Sikaflex to provide protection, and can't say I've noticed any problem.

cheers
phil

Hi All
If you cant dazzle them briliance,
Baffle them with bull shyte.

Galvanic corrosion is discussed in welding text,metalurgy text aswell..anyway goodluck with your trayback.

All The Best In Health And Wealth
JD

Hi JD,

I'm well aware of the issues of galvanic corrosion. But I've learned not to believe everything that you read in a book. I asked the bodybuilder about it, as they work a lot with aluminium, and he insinuated that for small areas, it wouldn't be an issue.

Every alloy tray I've seen has had aluminium riveted to galvanised steel. Can you let us know how much of an problem this is?

Cheers
Phil

Hi Phil G,
As I stated in my originall post..this my opion only..and you should keep an eye on it..why do some trucks turn into rust buckets and others don't?? small areas..big areas.. contact is contact and and that is where the rust will occur..how long will it take..well we go back to why are some trucks rust buckets and others not???as to not believing trade texts which I refer to I will give you a theoretical representation of why you need the back up of the written text..for instance you have lets say a home trained welder/fabricator who makes his own towbar up ,he does a beutiful job welds are great that is they look perfect the bar fits in first time..he gets heaps of praise from his friends for such a great job...but in service it breaks and sends his $20.000 camper hurtiling down the hwy to some awfull fate..his only mistake was he made it out of high carbon steel..looked great but was brittle this is where you need the text to back up practical.as to how much of a problem it is? I know it exzists but to what extent in this situation I don't know that is why I said keep an eye on it as you would in suspected rust situation.
JD

Hi JD,

Thanks for the reply. I think this is interesting stuff. A few companies are making trade canopies with steel frames and aluminium cladding, so I guess one day I'll have a closer look and see what they do.

As I mentioned above, I've been using Sikaflex between areas of contact between aluminium and steel to prevent the galvanic corrosion. The main areas of contact I have are bolt holes, but like you say, I'll keep an eye on it.

Sorry I was a bit too cynical above about the books, of course you must abide by the core knowledge, but if I'd had one less red last night, I may have expressed myself better :-))

Cheers
Phil

John,

The two manufacturers I looked at are in Qld,one in Bendale, other at the coast somewhere[they work off agents & I have not been able to locate the actual factory]

Contact: au/dot/com/dot/optusnet/@/sunfish3

Please quote "canopy" in the subject line as the spam filter is fierce!

eng

Reiner,

Thanks for the suggestion, but I am paranoid about security, thats why I settled on a "securable" canopy. The truck is my daily runner & there are some bad dudes out there!

eng

Gday Wok, just going through this same excersise at the moment. I'm looking at the same thing as Reiner has suggested but for the security issue was going to use that screen door security mesh under the canvas which opens up and will also serve as shelter when open. And with the canvas fitted using sail rail I should be able to easily take it off to make it an open air canopy so I can throw the dogs in to take them down to Deception Bay for a swim. Let us know on what you eventually get.

Cheers
Al

should have mentioned it's alluminium on a steel frane
cheers toohey

Hello Toohey,

Thanks for the link...neat looking units. How much weight could you put on top?

eng

lowline say up to 1 tone if distributed properley
cheers toohey

Thanks Toohey,

Looks like load-bearing won't be an issue for the lowlines.

eng

My dearest Lucy,

The regret to advise you that you have your k$$#%%ers in a knot; I am uncommitted in the marital stakes. However,I did respond in that thread when I felt there were aspersions been caste upon my name :) It was all in fun..............I did have a thread vaporised recently....too controversal me thinks.

Hugs & Kisses.....eng

Phil,

I have looked @ your setup...looks great. I have combined a few ideas for mine which will have a similar profile to yours. I already have a tray so a new floor isn't necessary.

Since posting, I have decided to add a vent to the front of the canopy to "pressurise" the cavity [ rudimentary dust control]. Still working on the filtration system.

Is the gap in your door waterproof if it were open in rain?

Thanks for the ideas.

Eng

Eng,

On mine, theres no need for the vent. It is dust free inside. Dust only gets in a back door - it doesn't get in side doors, so as long as there is good sealing all round, you don't have an issue. Don't by a vent now - get it later if you have a problem.

The profile of mine is that it taper starts 400mm above the tray, which is where the handles of the engel sits out. We decided to taper the sides so that the base was 1750 wide at the tray, and 1500wide at the roof. I trimmed my tray by 50mm each side - I wanted to minimise overhang and width, which all work against you when offroading.

The doors are nicely built and ahve a good rubber seal all the way round. The door handles and locks are the newer type which tighten up as you do the final close.

As I said, its been great fun setting up. I have two other mates with similar setups and canopies and we compare ideas.

Its now a year since I bought the vehicle, and I've been setting up the canopy for the last 8 months. We've had two desert trips now, and are very pleased that this is a great way to travel, so enjoy setting yours up.

Cheers
Phil

giday phil
no dust gets in the rear door of the lowline,they've a great seal on em'.
cheers toohey

Phil,

I am toying with trimming the sides as well [to keep the width within the cabin profile]. Did you trim your tray in-situ or did you take it off the chassis to chop?[ yes, I am lazy!] Off course this will be irrelevant with glass as the moulds are "standard".

The wall taper will follow the cabin profile in my case.The fridge needs to be on a slide as there isn't enough headroom to lift the lid within the canopy.

The primary function of the vent [ & outlet] is for temperature control of the cavity [reducing the load on the fridge]. The dust part is a bonus.

So far the groundwork has been fun [albeit confusing at times]

eng

Hi Toohey,

A rear door would have prevented me from simply fixing the spare tyre to the back - My spare is attached using vehicle spare parts - a U-bolt, a piece of RHS with a couple of wheel studs, and wheel nuts, and its very solid, without adding the extra weight of a carrier.

I wasn't familiar with the lowline, but just looked at the lowline site and they look very nice - similar concept to what I've had built. I preferred not to have windows on mine, given the hot SA sun, and didn't want spying eyes.

Cheers
Phil

Wok,

I did it with the tray still on. My tray was 1860 wide. I trimmed it to 1750 for the reasons you mentioned. I fitted and bolted the canopy on, marked it out with a texta, then unbolted the canopy, slid it sideways, removed the tray's side rail and ran along it with a circular saw - the normal blade is OK for light gauge aluminium. I then redrilled and attached the side rails, so it was all a perfect fit. My canopy is primarily attached to the tray with 4 H/T 12mm bolts that go thru the floor and into the steel rails below. I figured that would be stronger than the side bolts you see with some, and I wasn't planning on removing it.

Fridge slides are optional. I haven't used slides because I wanted to keep the Engel as low, and as secure as possible. I can fit 2 engels next to one another - they are right up to front panel, and are able to sit behind the pillar. They sit on HD foam, and are secured by adjustable straps. The lids open fully (just!), and I can lift out the wire baskets OK. If I were to use a slide, the fridge would have to sit about 2 inches higher to clear the lip. Only advantage of the slide is that you can store stuff above it, but storage space is not an issue for me, so I leave the area above the fridges open, and use the area for some mesh baskets above the rear of the fridges.

As far as temperature inside goes, again, for me, it hasn't been an issue so far. I bought some vents from Whitworths, but probably won't bother using them. Because mine is white, and aluminium, and has no glass, it seems to reflect pretty well and stay at about ambient temperature anyway. When we're away, it is opened for morning tea, lunch and as soon as we camp. It definitely cooler in there than the back of a car. Again, I tend to suggest that you see how it goes, then add a vent later if the need is there. I have two mates with similar canopies, and none of us have bothered with venting.

Cheers
Phil

Stuart,

Brisbane..Northside

eng