Body to chassis bonding

[johnnyp]

Hi guys i am counting the days until my gleaming (ok who am i kidding, dull primer grey.....) body arrives for my DAX Toj rolling chassis that is currently the pride of joy in my garage, so the question is, when bringing the body and chassis together the manual suggests that the powder coating on the chassis that interfaces withthe GRP should be removed prior to bonding.

Can i ask what others have done, have you done as the manual suggests and strip off the powder coating (looks like a long and laboreous job to me for little gain) or do you just bond straight to the powder coat.

Answers much appreciated

[craggle]

Leave the powder coat alone and stick the glue on top.

Seems little point in breaking the only corrosion protection the chassis has.

Craig.

[tonym]

Originally Posted by craggle

Leave the powder coat alone and stick the glue on top.

Seems little point in breaking the only corrosion protection the chassis has.

Craig.

And being a Dax, you'll need it

[craggle]

I did enquire about a galvanized finish when I ordered my chassis and got told that the heat from the process could distort the chassis and it adds a lot of extra weight.
I did think of getting it done but then didn't and brought the powder coated version instead.
The finish on my chassis was good though and there are no signs of any damage to it yet.
Are pilgrim the only one to offer a galvanized option or do others do it too?

Craig.

[stevey]

mine is a budget Euro 427 and is finished in Finnegans green hammerite
Steve - enjoying a slack day in the office with far too much time on his hands!

[Lloyd Barnes]

Just bonded and riveted mine together a couple of weeks back. Left the powder coat in place but lightly sanded the surface to make sure the wurth key properly to it. Whole thing seems totally solid, I'm glad I left it alone.

One possibly useful bit of advice, check the clearance between the front suspension upper arms and the inner wings when you trial fit. Nowhere near enough gap on one side on mine but only spotted it after bonding together, took ages to trim it in place.

[johnnyp]

Cheers guys, lots of good advice and i am more than happy to leave the powder coat in place but as suggested will sand it to provide a key first.

Can i also ask what the part number of the Wurth adhesive supplied by DAX is? i want to cross check it with polyurethane adhesives we use here at work.

cheers

[bogster]

Originally Posted by johnnyp

Cheers guys, lots of good advice and i am more than happy to leave the powder coat in place but as suggested will sand it to provide a key first.

Can i also ask what the part number of the Wurth adhesive supplied by DAX is? i want to cross check it with polyurethane adhesives we use here at work.

cheers

I definitely recommend removing the powder coating.

You only remove a strip of powder coating on the chassis where the adhesive will take its place.

I spoke to Peter Walker at Dax about this prior to installing the body and he assured me the best way to ensure a solid, secure bonding to the chassis was to remove the powder coating otherwise the Wurth will eventually lift the powder coating off the chassis and stress the riveting.

My recommendation is to remove a strip of powder coating approximately 1" in diameter along the centre ling of the chassis rails were the body will contact the chassis. This way when the adhesive is applied and the body installed the adhesive replaces the powder coating and no bare metal is left exposed.

[stevey]

gents, I have debated about adding this post but if it stops one our fellow builders screwing up in a royal fashion I think this needs to be mentioned - for my sins I built a Euro427 which fellow owners will know is legendary in the total lack of build manual and with the odd slip along the way it is now happily on the road BUT I neglected to seal between chassis and sills! I know fecking idiot but there that is what I have done. I checked my LARGE rivets which hold the sides and am horrified to see thay are fretting so I have got some panel sealant from my bodyshop and will be drilling/filling along the sills this weekend to fix the problem:0( just a thought while we all enjoy a good laugh (often at each others expense) a thread like this shows the tremendous value of a forum like this--- and to start the p*ss take ahead of everyone else don't follow my Cob to close you might find the body joining you!!!!!!!!!!
Steve

[JonnyT]

Hi johnny,

There are lots of posts on here about how to fit the body, all of which are pretty useful in ensuring that things get done before they are totally inaccessible when the body has been bonded on.

In regard to removing the powder coating I have to say that it seems to me far better to have something bonded directly to the metal of the chassis (and the wurth will prevent any corrosion) rather than to powder coating which in the fullness of time will inevitably lift off in places reducing the strength of the bond.

Two things that you should check are:

1. The tubes welded to the chassis through which the scuttle hoop bolts were in the wrong place on mine. Much much easier to remove and reweld before the body goes on (but make sure any electronic ignition items are disconnected and isolated before electric welding).

2. (and see previous rant). At the rear of the chassis are two rather odd shaped plates with two holes in them. These are meant to be for the rear nudge bar and overriders. Unfortunately they are in the wrong place by about 10mm. If I were you (and having been in increasing levels of rage for about 5 hours trying to sort this out last weekend I feel qualified to comment) I would weld up the holes in this plate and grind them smooth and then add another 25mm of plate inboard of each plate with the weld ground flat to allow drilling after the event. Also ensure that you fill the radiuses because they will likely fall exactly where the new holes are to be drilled. Please let me know if the above makes no sense and further explanation is required. You may also find that these plates have to be trimmed anyway to get the body to sit down flat on the back bar.

HTH

Jon