DS Footbox - Access Panel Question

[John Ibele]

I have an older MK4 kit which doesn't have the access panel into the top of the DS footbox from the engine compartment, so I'll be making my own. I found a number of images which should allow me to get close, but measurements to get closer would be a real help.

While I'm at it, no reason I need to just duplicate the factory panel. Does anyone have suggestions for improving on the stock panel dimensions / location?

Also, I've thought that Dzus fasteners (invented for holding aluminum aircraft panels securely in the presence of vibration) would be a cool thing to use here instead of rivnuts to allow access. Has anyone had experience using these in a roadster build?

[Garage Guy]

I did not use the dzus Fasteners on my build in that area but I thought about it. I have not seen them in over 30 years my experience with them was in the military on aircraft. They were rugged as hell and stood up to years of abuse and we're not always treated with respect. But a very tough fastener the only downside I see is they are expensive and take up a lot of Real Estate with the body on there is not a lot of room in that area. If you ever had to change out a master cylinder you will want that opening as big as possible. But I think with good planning and execution you could make a good-looking access panel with them. I don't see them as any kind of a safety concern after all they are used on race cars and aircraft where takeoffs are optional and landings are mandatory. I can see the comments rolling in now " Don't overcomplicate things.", "Too expensive.", "Just go with what people have done before." Remember this though, it is your build and as long as it's not a safety concern build it the way you want to. You ultimately have to live with it so build it the way you want. After all the manual says to rivet it in place so even rivnuts are an upgrade. Hope this helps

Richard

[Railroad]

Does not look like you will need fastners in the rear outside corner of the cover. Others had confirmed this, but did not pick up on it, until I set my body on. Not a big issue. I will just leave out that screw, but might save you drilling and putting a fastner in that area.
Also, I wish I had put fewer fastners, maybe 4 total is plenty.

[John Ibele]

Thanks Richard, I've never seen a Dzus fastener myself, so your comments help. I think its Rivnuts for this application, since they're compact and couldn't be cheaper (since they're sitting in the garage).

Railroad, thanks. I've seen some covers where the outer rear section seems to follow the line of the hood opening, which makes sense since it would be tough to use any space under the body anyway. Does it make sense to make some tabs (offset by the aluminum panel thickness) for this area, and combine it with 4 fasteners covering the front and inner sides?

[GWL]

I used Dzus fasteners in my trunk for access panels to storage boxes and access to the fuel pump and fuel gauge sending unit. They were a bear to design and install but it the end I do like them. It's been a while and I'm in the middle of setting up my old computer that has all my pictures. I'll try to post some pictures later.

George

[Railroad]

The cover provided and the one you make should have no issues covering the opening. It is just that particular corner is not accessible for a fastner. I would not think you need to add anything for support in that area. Just put 4 or 5 fastners where they look good and are easy to access. Hope I am on the same page with your question.
It seems, not close to the car now, that the cover could be marginally larger, more room to get those rivnuts off the edge of the opening.
I'll bet you make a cardboard one first and check for an easy fit.

[Boydster]

<snip> Does it make sense to make some tabs (offset by the aluminum panel thickness) for this area, and combine it with 4 fasteners covering the front and inner sides?

This is exactly what I did. Made some tabs, offset for the thickness of the sheet, along the outer and aft section. Then just a few rivnuts and screws.

However, after mounting the body, I found that I could have just put screws all the way around with no issue. I have a few access panels I'd like to go back and redo with dzus fasteners, and this is one.

[Avalanche325]

I made my own. My kit was just before the access panel was added.

1. Make it as large as you can. I actually changed my entire pedal box and converted to a hydraulic clutch on a completed car. Bigger is better.
2. You want to keep it watertight. I used gasket material, and rivnuts.
3. It is part of the firewall. Literally to keep fire off of you if something goes wrong. Keep that in mind when designing and choosing fasteners.

If you have a thing for Dzuz fasteners, just make sure that you have enough room with the head popped up. There are different head types. I would say that rivnuts and button head screws keep things tight and low profile. It does take a few minutes to take them out, I spaced them just like my rivets so there are quite a few, but it is not like you would ever need to get in there in a hurry.

[phileas_fogg]

The pre-Coyote cover dimensions are 9 1/4" along the bottom edge (closest to the engine & longest of the sides), 5" along the front edge, 6 1/2" along the top edge (closest to the side of the hood opening), and then a smooth curve back & around to the bottom. The cover overlaps the opening by 1/2".

With those numbers and some poster paper you should be able to get a reasonable facsimile.

I used #10-32 riv-nuts spaced ~2" apart (just like rivets). I can get a Phillips head screwdriver onto each, though the shaft of the screwdriver is tilted relative to the screw's axis on a couple of them.


John

IMG_4435 by jhsitton, on Flickr

IMG_4895 by jhsitton, on Flickr

[John Ibele]

Thanks all. John, that is a super help, both the pictures (particularly where the body falls in relation to the access panel) and also the dimensions. I have everything I need to know what to do next now.

Cheers,

-- John