Headlight bucket grommet

[Eneto-55]

I don't get much time to do anything on my P15, so just little projects is all I can tackle.  I dismantled an old HP printer recently (to separate what can go to the landfill, and what is considered toxic waste, like the circuit boards), and saw the rubber paper feed rollers, and had an idea of a way to use them.

 

Made a mandrel and chucked it up in my drill, then shaped the roller into what I need to replace the grommet that fits into the headlight bucket.  The original wiring harness was molded in one piece - the grommet and the rubber sheath over the wires was cast in one go.  I was already planning to run the ground wire back to the terminal block (instead of screwing it down at the headlight housing) and some time ago i found some new 3-wire heavy gauge stranded electrical wire (with a strand count similar to the original wiring) in the dumpster behind the local hardware.  Rubber coated, not plastic like most of what you see being sold now-a-days.  But I still needed the grommet.  

These paper feed rollers are just a hair smaller diameter than the original MoPar grommet, so it was a good match.

 

In the picture, from left to right, is an original paper feed roller, my first attempt (I got the groove too deep & too wide on this one), the first successful one, then the original harness and the jig I turned it on.  (On the first try I didn't have a lock nut on the jig, and the resistance of the wood rasp I used to make the rough cut spun the grommet a bit, and that tightened the nut, which compressed the rubber roller, which I didn't notice until I stopped the drill for a look-see, and the rubber was really pushed out of shape, and the saws-all blade I was using to cut the groove went too wide.  Used the same blade on the second one, but the lock nut prevented the rubber roller just tight enough to keep it from spinning on the jig.)

 

Now, will this type of rubber last?  That's something I do not know how to evaluate.  But if someone manufactures these, I've certainly never seen them available anywhere.  And, should I coat the surface with silicone rubber?

 

[Sniper]

Good job. no help on your question though

[Eneto-55]

I thought of the fender light harness this morning (aka "parking light"), and now I see that it is made the same as the headlight harness, and the hole in the housing is in fact the same size. So now I need to find a suitable rubber coated cable to use there as well.  (What I have for the headlights is heavy gauge - wouldn't hurt to use on the fender lights, but all of those wires in there might get kinda' full.  I say "all of those wires" because while the original is just a single wire, I want to add turn signal capability, and a ground back to the terminal post.  Better to find some 16 gauge wire. I don't want to use just plain wire, because it's an exposed area, and I don't want to do anything that is worse than original.  I suppose a person could wrap it with that self-vulcanizing rubber or teflon tape, but I still don't think that is quite as good as how it was done originally.)

[Plymouthy Adams]

IF you are out to turn some rubber from stock into push in grommets be it on a lathe or drill press etc.  You can get rubber stoppers in various sizes pretty economically might I ad at places like Lowes and other well stocked specialty hardware isle of your favorite place you shop.  This is pretty much a common practice for hard to get items, these stoppers have many uses in the auto hobby.

Edited June 2, 2022 by Plymouthy Adams

[Eneto-55]

36 minutes ago, Plymouthy Adams said:

IF you are out to turn some rubber from stock into push in grommets be it on a lathe or drill press etc.  You can get rubber stoppers in various sizes pretty economically might I add at places like Lowes and other well stocked specialty hardware isle of your favorite place you shop.  This is pretty much a common practice for hard to get items, these stoppers have many uses in the auto hobby.

Having a centered hole of the correct diameter is a big advantage, as (in my experience, at least) drilling a hole in rubber, or drilling out an existing hole, generally doesn't work well.  I have seen stoppers that DO have a hole in the center, but usually they are not the correct size, or the overall diameter of the stopper is insufficient.   But I also readily admit that I'm a tight wad who prefers to repurpose stuff that would otherwise go to the dump.  And sometimes I end up wasting time in that endeavor, too.

[Plymouthy Adams]

I agree, repurpose as much as you can and save the jingle for that you cannot create......invest in a square hole bit set, smaller common sizes are sold in package of 5 different sizes.  Make holes in plastic and rubber so much easier and can actually drill a stop depth with them.  

[Plymouthy Adams]

Back inside for a bit of cool down, 97 out there and a bit humid yet also.  Anyway, took a minute to find the bit set I was referring too....they are called brad points and are keen for wood workers.  I was fortunate to find this set at local estate sale for 5.00 unused.  Then you may be interested in the smaller package usually at hardware/supply stores.

 

Smaller set link:  Topzone 8 Pieces 1/8 - 3/8" Brad Point Drill Bits Set for Wood" | eBay

 

 

Edited June 2, 2022 by Plymouthy Adams

[Eneto-55]

3 hours ago, Plymouthy Adams said:

I agree, repurpose as much as you can and save the jingle for that you cannot create......invest in a square hole bit set, smaller common sizes are sold in package of 5 different sizes.  Make holes in plastic and rubber so much easier and can actually drill a stop depth with them.  

Until I saw your picture, I imagined one of those mortising jigs that drilled square holes, for furniture joinery.....

 

Anyway, thanks.  After I made that last post, I wondered if freezing the rubber before drilling would make it work better.  Never thought of it before.  Or, maybe using a reamer instead of a drill bit, as it has more cutting edges.  But I don't have many reamers.  What I encountered with trying to drill rubber in the past is that it just deforms as the cutting edge passes, or gouges, and then goes off in some unwanted direction.  I imagine that different types (hardness) of rubber would behave quite differently as well.  This stuff from the printer paper rollers is pretty soft stuff.

Edited June 2, 2022 by Eneto-55

[Plymouthy Adams]

this is why these brad points do so well in soft material like rubber and plastic....the brad point bites and guides without walking and the outer edges cut the circular portion of the hole before the center core is cut out by the rest of the bit.  Freezing may help, never have done that so cannot relate any experience here.  

[Eneto-55]

A question occurred to me about what I'm planning to use for the terminal to headlight bucket wire harness - a piece of heavy gauge electrical extension cord.  In a completely different context, when I told someone that I was planning to use a 12/3 extension cord in a 12 VDC application, they questioned whether that wire is different than what would be intended for 12 VDC.  Anyone know?  (I did do an on-line search, and it appears that other than the voltage loss experienced in a long run of DC, there is no difference.  The run in question is around 18 feet, and the specified gauge is 14 to 12, so I was planning to use 12.  The advantage of the extension cord is that I would use the normal 120 VAC plugs/receptacles.  This would all be hidden in the final set up, and in an area where no AC is available.)

Edited May 30, 2023 by Eneto-55
additional comment

[DonaldSmith]

It might be a bad idea, for the next owner, or some itinerant mechanic. to have house-style plugs and receptacles.  Someone may plug it into an extension cord plugged into the house and poof! Or worse yet, Zap!  

[Plymouthy Adams]

as I read this, he is planning on using just the wire and not the actual plugs of the extension cord...use stranded wire for DC.....you can use this if you wish.....you could not begin to count the number of car trailers and such wired with extension cord donors....just too quick and easy, nice protective coating over the wires...

[Eneto-55]

In this application (for the Plymouth) there would be no use of the 110 VAC connectors - just the raw wire itself.  

 

[In the other (off-topic) application, I would probably use the 110 extension ends as is. 

(This was in an area where there was no AC power of any kind for 25 to 30 miles, but I used 120 VAC air conditioner receptacles and plugs for a 12 VDC solar array system we installed in our house there.  I just used the two slanted prongs.  That prevented the plug from being inserted backwards.  But like I said, no AC power anywhere close.  We didn't ever have a generator, either.  If we couldn't power it off of a single automobile battery, it didn't get done.)  I would also remove all of this when/if this off-topic DC equipment left my control.]

 

But my main question here is as to whether I can use raw extension cord for the headlight and fender light harnesses on the P15.  Like a good quality extension cord, the original Plymouth cables in this area were cast in rubber, but are now so dried out and cracked that they are completely unusable.  I figured that the rubber coating would be better than just wrapping regular automotive wires.  I also already intended to run the positive ground wire back to the terminal block on the radiator side panel anyway (instead of just grounding it to the head light bucket).

[LazyK]

40 plus years in the electrical distribution industry.

There is no difference in the wire it self.  Both are manufactured to AWG standards. The difference would be in the anealing of the copper and the number of individual strands in the conductor. The portable cord will have more strands and be softer(more flexible) than standard automotive wire. The insulation will also be a rubber compound material.

In short 14 gauge wire will carry the same current regardless if it is portable cord, automotive, or building wire.

[Eneto-55]

2 hours ago, LazyK said:

40 plus years in the electrical distribution industry.

There is no difference in the wire it self.  Both are manufactured to AWG standards. The difference would be in the anealing of the copper and the number of individual strands in the conductor. The portable cord will have more strands and be softer(more flexible) than standard automotive wire. The insulation will also be a rubber compound material.

In short 14 gauge wire will carry the same current regardless if it is portable cord, automotive, or building wire.

Thanks.

Speaking of strand count, one thing I've noticed is that back in the P15 manufacturing era they used wire with a significantly higher strand count than they did later.  I haven't done a count on any vehicle later than a 93 Chrysler T & C, but I found broken wires on the engine harness on that vehicle, and I don't think there were any completely severed wires on my 46.  

Strand count is also a bit of data that the places that are manufacturing replacement harnesses don't tell you, at least not that I've seen.  Another reason why I plan to build my own.  (Also planning to use marine grade wire, which is not only typically higher strand count, but also tinned copper.)  I had thought of building wire at one point back when I first started looking for wire for the Plymouth, and it looked pretty attractive price wise, but it has a really low strand count.  (I do not recall the numbers, but you probably already know.)

 

I hadn't thought of the difference that annealing would make, and I don't think I've seen any data on that at all, on any wire vendor's spec sheets.

Edited May 30, 2023 by Eneto-55

[JerryinTx]

On 6/2/2022 at 5:42 PM, Eneto-55 said:

Until I saw your picture, I imagined one of those mortising jigs that drilled square holes, for furniture joinery.....

 

Anyway, thanks.  After I made that last post, I wondered if freezing the rubber before drilling would make it work better.  Never thought of it before.  Or, maybe using a reamer instead of a drill bit, as it has more cutting edges.  But I don't have many reamers.  What I encountered with trying to drill rubber in the past is that it just deforms as the cutting edge passes, or gouges, and then goes off in some unwanted direction.  I imagine that different types (hardness) of rubber would behave quite differently as well.  This stuff from the printer paper rollers is pretty soft stuff.

When I was searching for replacement grommets for my headliner bows, I bought grommets from McMaster Carr. The ID of the center hole was too small.  I tried freezing and drilling them.  No workie!  Then I tried a long diamond bur in a Dremel tool and it easily enlarged the hole to perfect size.