The great switch-er-roo...!

Iluvspeed · #1 (**permalink**) 08-27-2018, 05:36 PM

All,

I have several spst (on-off) toggle switches on my dash, that decidedly are not period correct.

I ordered a pair of Lucas duckbill (paddle) handle switches as replacement, but these were apparently designed for mounting on a very thin (metal?) dashboard..... the threaded shaft on the switch barely is visible from the cockpit, and fitting the locking bezel is pretty impossible (I tried)....

Seems I might have two alternatives:

1. remove some of the fiberglass from the rear mounting surface of the dash, so that the switch shaft is more exposed in front. (Not my idea of fun, since the dash is fully wired/populated, and only easy to partly open....)

2. Find an authentic Lucas (or other make) duckbill switch that is period correct, but with a longer threaded mounting shaft.

Anyone "been here" before--and how did you resolve this one?

Thanks.... Ken

P.S. I would have posted pics, but I haven't been able to "break that code" yet.

Grubby · #2 (**permalink**) 08-27-2018, 05:51 PM

ERA supplies Lucas toggle switches with the kit and they fit fine in the fiberglass dash.

They are available from Finish Line and several other sources. I had to replace two toggles in 755 and the Finish Line pieces fit fine and looked just like the ERA supplied pieces.

I am not sure why you are having a problem.

John

Iluvspeed · #3 (**permalink**) 08-27-2018, 06:16 PM

Thanks, John....

Yup. The two toggle switches I received are from Finish Line, and are Lucas p/n SPB200.
Thanks for confirming they are identical to those initially sold by ERA in their kit.

I'll give Peter P a call tomorrow, and see if he has any thoughts on this one.....

Ken

66gtk · #4 (**permalink**) 08-30-2018, 01:04 PM

I've been in your shoes before. I had to take a dremel and carefully sand away the portion of the dash (backside) to recess it enough to hold the nut down on the front. I found a way to do this on my installed dash by putting a sanding disk backwards on the the dremel after I pushed the dremel through the hole and then apply a pulling pressure as I sanded away material on the backside.

vntgspd · #5 (**permalink**) 08-30-2018, 01:27 PM

Quote:

Originally Posted by 66gtk

I've been in your shoes before. I had to take a dremel and carefully sand away the portion of the dash (backside) to recess it enough to hold the nut down on the front. I found a way to do this on my installed dash by putting a sanding disk backwards on the the dremel after I pushed the dremel through the hole and then apply a pulling pressure as I sanded away material on the backside.

Genius! I haven't had to do that but I will remember the trick.

spdbrake · #6 (**permalink**) 08-30-2018, 01:42 PM

I too thought a set of vintage Lucas switches would be nice in my Backdraft.

I used a reverse spotface cutter to counter bore the inside of the dash panel.
Like these: https://cogsdill.com/products/deburring-tools/flipcut/

And switch Id labels. https://www.bits4landys.co.uk/series...s-switches.htm

My selective memory was active and I totally forgot about the pains I endured while a youngster and my MG and Lucas. Needless to say one of those Lucas switches running my Electric fuel pump on the Cobra died one night and luckily I swapped connections with cooling fan override switch next to it and got home. The Lucas switches are at home in the landfill now.
Lucas - Prince of Darkness - Lucas Electrical Humor Jokes

DanEC · #7 (**permalink**) 08-30-2018, 02:22 PM

Quote:

Originally Posted by spdbrake

I too thought a set of vintage Lucas switches would be nice in my Backdraft.

I used a reverse spotface cutter to counter bore the inside of the dash panel.
Like these: https://cogsdill.com/products/deburring-tools/flipcut/

And switch Id labels. https://www.bits4landys.co.uk/series...s-switches.htm

My selective memory was active and I totally forgot about the pains I endured while a youngster and my MG and Lucas. Needless to say one of those Lucas switches running my Electric fuel pump on the Cobra died one night and luckily I swapped connections with cooling fan override switch next to it and got home. The Lucas switches are at home in the landfill now.
Lucas - Prince of Darkness - Lucas Electrical Humor Jokes

I' ve had the same experience with two Lucas switches going bad. I have found them pretty simple to pull apart and repair however.

Iluvspeed · #8 (**permalink**) 08-30-2018, 04:12 PM

Hhhhmmm. I responded to this thread late yesterday, bit it appears to have gone to some internet-bit bucket.....

I realized the Lucas toggle had a bit of a lip, where the threaded boss contacts the switch body.

The prior owner/builder had used bat-handled switches that fit in the hole he had drilled. The Lucas toggles would fit in the hole, but that lip was too large for the drilled hole. The fix was easy-peasy.... Took a good rat-tail file and about five minutes per hole; I opened up the hole, and the Lucas switch fit tightly. Problem solved. I had enough of the Lucas switch exposed to accept its locking bezel.

Thanks for the help.... I hope this posting makes it to the thread(!)

Iluvspeed · #9 (**permalink**) 08-30-2018, 04:22 PM

..And, oh..... horror of horrors...!

Installed both switches and one appeared to be bad. Pulled it from the dash, and checked it with my digital ohmmeter, and it tested good. (Wha???). Reinstalled it, and jiggled (technical term?) the two leads, and the Lucas toggle would work intermittently. Both push-on spade lugs were tight on the switch, but..... one of the leads had tension on it, in that it was tightly routed. Rerouted the wire to free it up, and all was good.

Apparently the tension on the Lucas terminal caused enough of an internal misalignment that prevented the innards from closing the circuit(!). Lucas...gotta love 'em....

The price we pay for authenticity!!!

patrickt · #10 (**permalink**) 08-30-2018, 07:09 PM

Quote:

Originally Posted by Iluvspeed

The price we pay for authenticity!!!

It doesn't get any more authentic than a Lucas switch that only works if you jiggle it just right.

66gtk · #11 (**permalink**) 09-02-2018, 09:26 AM

Quote:

Originally Posted by spdbrake

I used a reverse spotface cutter to counter bore the inside of the dash panel.
Like these: https://cogsdill.com/products/deburring-tools/flipcut/

Clever tool - how much does this thing cost?

spdbrake · #12 (**permalink**) 09-02-2018, 10:13 AM

Good question. I've never had to buy one. Expendables were always supplied by my employer. Another company that makes the same style of cutter is:
https://www.steinertechnologies.com/

Another type that is reasonable price wise and works quite well on aluminum are these. https://www.yardstore.com/drilling-a...everse-cutters
HS steel not carbide like the Flipcuts.

If you're ever in Wichita swing by the Yardstore. Used Tooling, Air tools, measuring, bits, cutters from Cessna,Beech,Bombardier,Boeing all end up there Cheap! Pennys VS $. They have quite a bit on their website used as well but prices are at least 2X higher on the site on used items.
https://www.yardstore.com/surplus
I wouldn't buy a used Pancake or Angle drill there though. Those need to be inspected for head wear personally. (wandering drill bits) Unless they note the heads are new.