767 replies to this topic

[Chris1992]

 

 

Looking good but all that filler will crack in no time i'm afraid.

 

I've heard mixed things to be honest    some people have said it should be fine, and others have said it'll shatter as soon as I run over a pebble... this maybe a mistake, but I'm a bit too far into it now, how much will the bulkhead flex? Will it really be enough to cause cracking? There is no filler over any panel gaps or joins, not like when I de-seamed it before, and the seams didnt crack (somehow) after a year of daily all weather use. 

 

Maybe I'm in denial... ah well, I guess I can always vinyl wrap the bulkhead if it does crack slightly. 

 

 

Not only that, but all that filler will weigh a ton. You better off getting a large steel sheet the size and shape of the bulkhead and welding it over the top of the existing bulkhead, as one large panel. Ideally it would be better to chop the bulkhead out and then weld in the panel, but plating over it would be easier, neater and take a hell of a lot less filler and tidying up after.

 

 

god damn it... I must admit, the only thing stopping me from going out there and attacking it with an angle grinder right now is thinking about how long I've spent shaping that panel (as i mentioned, its a lot further along than the pics above)

 

would it really add that much extra weight? keeping in mind I'm not building this thing for the track?  

[James_eaton_thewholething]

What about people that use filler on doors that are opened and closed all the time that doesn't really crack. How thick would you say the filler is on it ?

[Chris1992]

What about people that use filler on doors that are opened and closed all the time that doesn't really crack. How thick would you say the filler is on it ?

 

thats exactly what i thought before i started.... there are a couple places where it could be about 15mm thick, but i would say on average its probably around 10mm thick in the middle, getting thinner and blending to nothing at either end of the bulkhead

[Ben_O]

Don't get me wrong, i'm not criticizing. I just know how much work you re putting into this build and don't want to see you disappointed after it is finished.

 

It's not so much flex that would cause cracking, it's more that jarring and vibrations would cause the brittle filler to crack.

 

I used filler to flush out a tailgate on my old AX GT and it cracked within a week of just normal driving and i was sick as a dog about it (expensive paint job)

 

I love the idea though

[1984mini25]

10 to 15mm is far too thick and will in time crack like a large sheet of ice.

 

As for the tailgate thing, it used to be best practice to plate over the plate recess before skimming with filler. If you really need to fill anything deeper than 2 or 3mm, I've used a mix of p38 and p40 mixed together (so at least you have some chance of sanding the p40 afterwards) and then normal filler over the top.

[James_eaton_thewholething]

I would agree 10mm is pretty thick. The bodgers that "repaired" my car used about that much on the rear corner under the lights and most of that was cracked

[Ben_O]

 

As for the tailgate thing, it used to be best practice to plate over the plate recess before skimming with filler. If you really need to fill anything deeper than 2 or 3mm, I've used a mix of p38 and p40 mixed together (so at least you have some chance of sanding the p40 afterwards) and then normal filler over the top.

The Citroen AX has a plastic tailgate so it's can't be welded.

 

I screwed a rigid piece of plastic over the recess, filled the void with expanding foam and then probably 4-5mm of filler to smooth it all out.

 

Still didn't work

[Chris1992]

Don't get me wrong, i'm not criticizing. I just know how much work you re putting into this build and don't want to see you disappointed after it is finished.

 

It's not so much flex that would cause cracking, it's more that jarring and vibrations would cause the brittle filler to crack.

 

I used filler to flush out a tailgate on my old AX GT and it cracked within a week of just normal driving and i was sick as a dog about it (expensive paint job)

 

I love the idea though

 

I get what you're saying mate. I think I'm just in denial to be honest 

 

 

10 to 15mm is far too thick and will in time crack like a large sheet of ice.

 

As for the tailgate thing, it used to be best practice to plate over the plate recess before skimming with filler. If you really need to fill anything deeper than 2 or 3mm, I've used a mix of p38 and p40 mixed together (so at least you have some chance of sanding the p40 afterwards) and then normal filler over the top.

 

 

I would agree 10mm is pretty thick. The bodgers that "repaired" my car used about that much on the rear corner under the lights and most of that was cracked

 

 

 

thanks for the advice chaps. I've had a good think and chatted with my dad about it, and I think I'm going to follow your advice. Chop the damn thing out and weld in a new panel... 

 

Thought I had out-grown these school boy errors but apparently not!    ... I'll still upload the more finished pics just for the hell of it.

Edited by Chris1992, 25 December 2015 - 09:33 PM.

[timmy850]

Your twin 1 1/2 carbs also look an awful lot like 1 1/4" (and the manifold is upside down).

[1984mini25]

 

 

As for the tailgate thing, it used to be best practice to plate over the plate recess before skimming with filler. If you really need to fill anything deeper than 2 or 3mm, I've used a mix of p38 and p40 mixed together (so at least you have some chance of sanding the p40 afterwards) and then normal filler over the top.

The Citroen AX has a plastic tailgate so it's can't be welded.

 

I screwed a rigid piece of plastic over the recess, filled the void with expanding foam and then probably 4-5mm of filler to smooth it all out.

 

Still didn't work

 

 

That's the French for you, why make cars from steel and bolts when you can use plastic and tinfoil instead.

Edited by 1984mini25, 25 December 2015 - 11:19 PM.

[Chris1992]

Your twin 1 1/2 carbs also look an awful lot like 1 1/4" (and the manifold is upside down).

 

yeah i noticed the upside down manifold, it was like that when i got them, just haven't bother to change it yet. what makes you say theyre 1 1/4" ones?

[James_eaton_thewholething]

wouldn't want you to get it all painted up just for it to crack and then go horrible later on down the road. it would be a real shame

[timmy850]

Your twin 1 1/2 carbs also look an awful lot like 1 1/4" (and the manifold is upside down).

 
yeah i noticed the upside down manifold, it was like that when i got them, just haven't bother to change it yet. what makes you say theyre 1 1/4" ones?

The stud holes are vertical and not on the diagonal.

HS2 on left, HS4 in middle and HS6 on right

[MrBounce]

Just read the whole thread. That's some Mini you have Chris.


Definitely agree with replacing the filled bulkhead with fresh steel. Whilst you have the car in bits it's the perfect time. Weigh the 2 panels as well - you will probably be shocked how much the filled bulkhead will weigh...

[Chris1992]

The stud holes are vertical and not on the diagonal.

HS2 on left, HS4 in middle and HS6 on right

 

 

You are indeed correct! but I've also realised I completely messed up my post... I knew the carbs that I had were one size up from the ones on my dad's sprite, and for some reason I thought his were 1 1/4", but they are in fact 1 1/8" ... so thats my bad! 

 

 

Just read the whole thread. That's some Mini you have Chris.


Definitely agree with replacing the filled bulkhead with fresh steel. Whilst you have the car in bits it's the perfect time. Weigh the 2 panels as well - you will probably be shocked how much the filled bulkhead will weigh...

 

Thanks mate, I appreciate it. Yeah you have a good point, I just may have to push back the respray date... I will! and I will post the results on here!   

 

 

wouldn't want you to get it all painted up just for it to crack and then go horrible later on down the road. it would be a real shame

 

Yes that would be a real shame mate. Thanks for the advice, I shall definitely follow it.

 

 

so just for the hell of it, I may as a well stick up the photos of how far I actually got with the bulkhead, just to really make clear how silly i am.... 

 

 

 

Its a shame its all being cut out!!  ... ah well. Its a learning curve!!

 

One question though, do I really need to keep the bulge on the right of the bulkhead for the wiper motor? and the slot/recess/thing for the slave and master cylinders? because they may complicate things when it comes to replacing the panel if I have to work round them