Scuttle removal?

[sltous]

2 hours ago, JohnCh said:

I didn't realize there are two more rivets that attach either side of the scuttle to the dash tube (thought those were small dome head screws.)  @sltous and @11Budlite how did you handle that?  Can you put a rivnut in that tube?

 

 

Thanks,

John 

Glad you asked and @11Budlite had an answer   I've been losing sleep about that rivnut.  I think I might put a countersunk head steel M3 or M4 nut in there.  Willing to take a tiny weight penalty for a more robust rivnut in a relatively hard to replace location.

[JohnCh]

If an M4 rivnut will fit in that location, I'm going that route.  The M4 button head diameter is the same as the rivet it replaces, so aesthetically it's a wash, and the M3 heads are a little too easy to strip in my experience.  But then again, I'm a klutz.

 

I removed all the other things holding the scuttle in place: heated screen wires, wiper nuts, washer tube, some electrical box velcro'd to the underside, etc.  However, it appears removing it is a two-person job given the various bits that are in the way.  It will either take a lot of simultaneous maneuvering from both sides, or the windscreen needs to come off so the scuttle can flex a bit to the sides and clear everything.  I suspect some cars are easier in this regard given the hand-built nature.  The Westfield, in contrast, is a one-person job.  Unbolt everything and lift straight up.  

 

-John

[toldfield]

Do a search for Strap Duplicator available from Aircraft Spruce, Brown Tool Supply, and other aviation tool places.  

 

[sltous]

15 hours ago, JohnCh said:

If an M4 rivnut will fit in that location, I'm going that route.  The M4 button head diameter is the same as the rivet it replaces, so aesthetically it's a wash, and the M3 heads are a little too easy to strip in my experience.  But then again, I'm a klutz.

 

I removed all the other things holding the scuttle in place: heated screen wires, wiper nuts, washer tube, some electrical box velcro'd to the underside, etc.  However, it appears removing it is a two-person job given the various bits that are in the way.  It will either take a lot of simultaneous maneuvering from both sides, or the windscreen needs to come off so the scuttle can flex a bit to the sides and clear everything.  I suspect some cars are easier in this regard given the hand-built nature.  The Westfield, in contrast, is a one-person job.  Unbolt everything and lift straight up.  

 

-John

It looks like there's plenty of tube wall on my car to drill out for the M4 rivnut.  With respect to removing the scuttle I unbolted my aeroscreen first because I didn't realize the captive nuts it is bolted to could be removed as one piece so you're way ahead of me  

 

It was a bit of a pain to remove all the parts individually (and find clean, safe horizontal storage for everything) but with a little care everything came up easily.

[JohnCh]

Thanks @sltous, @11Budlite confirmed he also removes the windscreen first.  I read in someone's blog they recommend three (no, not a typo) people be on hand to remove the windscreen.  I might take a shot at doing it solo later today.  I think I can stabilize things enough with tape and cardboard that if it proves problematic doing it myself, I can get the windscreen safely back into place without damage.  Famous last words...

 

-John

[IamScotticus]

My advice is loosen the six window frame screws to relieve any tension  or just plan on removing the frame off the stanchions.

Stanchions attached to the frame scratch stuff.

I know.

[JohnCh]

I confirmed that with sufficient blue tape to prevent the windscreen from falling backward and protect the scuttle paint, removing the windscreen is indeed a one-person job.  For anyone doing this in the future, items to remove are:

• 26 rivets at the front of the scuttle, plus 2 more on the sides
• 4 scuttle retaining nuts that attach the scuttle to the chassis tubes
• Windscreen wiper arm nuts
• Windscreen washer tube
• The two screws in the pair of tonneau snaps on the top center of the dash 
• Wiring loom connection box secured by Velcro to the underside of the scuttle near the tonneau snaps
• Two heated screen wires located at either end of the windscreen.  I was unable to remove the grommets, so resorted to cutting off the connectors.  I'll probably replace them with bullet connectors that can slide through the grommet to make that process easier
• The windscreen with stanchions

You will also need a lot of blue tape and a Guinness to steady your nerves.

 

I'll add more pictures in my build thread.

 

-John

[Croc]

John - look at installing the captive nut bracket for the windscreen - makes it even easier to do the windscreen one handed.  There is a left and a right side of these.

 

Retaining Channel - LHS (caterhamparts.co.uk)

 

 

[JohnCh]

Thanks, I'll add those parts to the list.  

[sltous]

Hi John,

 

In the process of re-installing my scuttle and wanted to give you some updated notes.

 

I was able to use every other rivet hole instead of all 24 and it is adequate in terms of structure in my opinion, I am not worried about the scuttle - to - firewall mating surface flexing and causing issues.  Every 4th hole is definitely too far apart.  I haven't tried driving with the current setup yet so I don't know if there will be issues leaving every other hole open, I might consider a spot of caulk or some other kind of seal on the open holes if anything pops up that is annoying.

 

The plastic bolts I initially planned to use are a bit unsatisfactory.  I stripped one installing the first 8 (every 4th starting from the 2nd from the outside I think got me to 8) and switched to some stainless fasteners I had on hand when re-installing with every 2nd hole.  If you are super hardcore about weight savings damn the cost you might consider aluminum bolts or something exotic but to me the tradeoffs for the plastic bolt stopped making sense as soon as I actually tried using them.

 

Using the furthest outward hole may introduce challenges.  I skipped it because my drill couldn't reach  but I also think the rivnut might run into the scuttle and require some surgery

[JohnCh]

Thanks @sltous!  I wondered about those first and last holes.  I didn't have an issue drilling out the rivets in those locations but did wonder if I could drill perpendicular-enough hole for the rivnut.  

 

-John

[toldfield]

May I kickstart this discussion.  I've run into an electrical issue and may need to remove the scuttle.  However, mine appears to have some type of black sealant/goop between the bottom flange of the scuttle on the sides and the aluminum side panel.  Any ideas on removing this?

 

Thanks

 

Tom 

[IamScotticus]

Likely a silicone sealer to prevent water ingress.  Most likely will have to cut through it with a wire or metal blade. Possibly a length of string will work. Remove and reapply if desired.

 

This may be a good time to do the easy scuttle removal mod. 

Drill out all 14 or so rivets along the front firewall edge and insert 5/32 (or close to the original rivet size) rivet nuts. The holes in the firewall will need drilling larger for the rivnuts.

There are button head screws that look like rivet heads to replace with.

My 2 cents.

 

Edited April 6 by IamScotticus

[JohnCh]

I agree this sounds like something done by a PO. Is there any evidence that the scuttle has previously been removed?

 

I'd recommend using fishing like rather than wire. You're less likely to have an oops moment and damage the paint. Unless cars from that era used bolts to attach the scuttle, you will have a couple of studs sticking up that will block the line from reaching the middle section. However, depending on the material used, breaking the seal at both ends with the line may weaken it enough that you can safely slide in a plastic putty knife or trim removal tool into that area. You could also use a thinner, metal putty knife, but slide that in from the cabin side to minimize the risk of paint damage. Just be aware that the scuttle aluminum is thin. Try to avoid prying as that will likely result in some creasing or deformation. Any pictures?

[toldfield]

Here is a photo of the seam.  I don't think the scuttle has been removed since the car was assembled in 1982. Paint is not an issue as there is none.  I will try fishing line first and then maybe default to safety wire.  There are two bolts in each side that shouldn't be a big deal.  Drilling out 14 or even 26 rivets would only get me part way.  I seem to have 48 of them on 1" centers.  This all began when I replaced the wiper switch.  I've obviously disconnected a wire as none of the electric gauges work.  I'm too old and inflexible to get under there.  Besides it might be time to remove the accumulated stuff that has collected there in the last 40+ years.

 

Thanks for the help.

 

Tom 

 

[7Westfield]

Can you pull the dash, and go at it from that side?

 

My Westy has the same number of rivets, and the silicone

no way I'm ever going to take that apart

but the dash comes right out

Edited April 6 by 7Westfield

[JohnCh]

if you have a twin cam then your car is likely from the era when the dash was held in by rivets. if that's the case, and provided they also didn't glue it down, then @7Westfield's suggestion should be much easier. 

[toldfield]

From that era but the rivets are beneath the lip of the scuttle and not accessible, even with a 90 degree air powered drill.  I may have instrument panel PTSD from the time a friend removed the panel from a Cessna 140 with a Sawzall.  The tach is receiving 12 volts and is grounded, the other instruments don't work.  All of the fuses are good.  

 

 

[IamScotticus]

6 hours ago, toldfield said:

 Drilling out 14 or even 26 rivets would only get me part way.  I seem to have 48 of them

Please excuse my numbers,  I shouldn't drink and forum.

 You are correct.

[IamScotticus]

1 hour ago, toldfield said:

From that era but the rivets are beneath the lip of the scuttle and not accessible, even with a 90 degree air powered drill.  I may have instrument panel PTSD from the time a friend removed the panel from a Cessna 140 with a Sawzall.  The tach is receiving 12 volts and is grounded, the other instruments don't work.  All of the fuses are good.  

 

 

Noooo! You don't have to remove those. The scuttle isn't attached to the dash hoop.

The scuttle is hard attachto the frame on these three places.

 

The firewall is not fastento the chassis,  it sits in a groove.

Drilling out the front rivets isn't necessary,  it just makes it easier depending on how much stuff you would have to take off the firewall. 

Leave those dash rivets in place. 

Sending a PM.