Ignition coil repotting tar

[Moxie26]

I have had no luck with my local suppliers to get the type 3 steep roofing tar. What contacts in your area carry the 50 pound blocks ? Thanks for your be help in advance..... . .. central/southern New Jersey...... The past two years with covid really affects businesses stock and locations that are still open.

[Steve Jelf]

Have you tried a Google search?

[Moxie26]

Yes I have Steve, only for them to tell me that my local home Depot is out of stock.... Still looking

[John kuehn]

Have you contacted any of the local commercial roofing companies or lumber yards? Maybe they some.

[Will_Vanderburg]

Try these people

[Will_Vanderburg]

Or maybe here. Unfortunately it’s a cylinder that weighs 100 pounds

[Moxie26]

John ..... I did contact three commercial suppliers, I was asked if I was a contractor of which I responded " no "..... And was told by all three , sorry no stock on premises. With contacting those out of the area on their websites and follow up by a phone call I was told I had to buy a full pallet, not a 50 lb slab. ..... My thought is that there is a shortage and only will be making sales to licensed contractors..... May be the sales restriction has something to do with rebuilding Florida homes that were destroyed recently

[John kuehn]

Mox. Just one more thought. Maybe call the smaller independent contractors that do the smaller flat top carports and roofs. They just might have some leftover chunks and pieces you can either get for free or buy them. There is some around somewhere that’s left over. Good luck.

[Moxie26]

Thanks John, that's a good tip.

[got10carz]

Why not call Ron Patterson or Brent Mize to see if they'll sell you what you need?

[John kuehn]

Can the tar from old coils that the wood is to bad to use be used again? You may have some junk coils around.

[Moxie26]

John..... John I do save and reuse the chipped out tar and do use tar from boxes far from being rebuilt due to bad secondary windings and/or bad wood. ..... Always need to add more on re-potting. Next few days will check out roofing contractors. Thanks again !

[Moxie26]

Got10.... Postage would be more than the value of the tar, but thanks for the comment.

[TRDxB2]

Just a thought......
Pro's and Con's of using Type 3 roofing tar for coil box insulation
-Stabilizes the condenser from movement; provides both moisture and electrical insulation
-temperature range has never been an issue Melting point is 158°F to 167°F.
-both easy & messy to apply or remove
-Availability is an issue
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Pro's and Con's of using a wax based filler like Paraffin or Bees Wax
-Stabilizes the condenser from movement; provides both moisture and electrical insulation
-both easy & messy to apply or remove but less than Tar
-Availability is not an issue
-Temperature range may be an issue
High melting Point Paraffin - three general grades: Low Melting: 125 °F to 135 °F. Mid Melting: 135 °F to 145 °F. High Melting: 150 °F to 165 °F
Bees Wax 144 to 147 °F

[Tim Moore]

I know expanding foam is NOT what to use as it can swell the coil but wonder if hot melt glue would work. It is cheap and would be far less mess if you have the glue gun. No stink or pouring out of a can and you could be accurate in application.

Heck I might try it this winter as I have a couple of sets to do myself.

Tim Moore

[Moxie26]

Frank and Tim ....... Really now , you would substitute those items for Type 3 steep roofing tar ???? You should have been there in the day to convince Henry Ford to save money . By the time the coil box made it to be mounted on the engine it would have been a sloppy gooey mess.

[TRDxB2]

Frank and Tim ....... Really now , you would substitute those items for Type 3 steep roofing tar ???? You should have been there in the day to convince Henry Ford to save money . By the time the coil box made it to be mounted on the engine it would have been a sloppy gooey mess.

My suggestion is based on the melting points of each of the solutions - naturally these values need to be confirmed
If they are then they could be used. Henry Ford used what was least expensive solution available in his day. Just following his lead. Item$+shipping$

Type 3 steep roofing tar melting point is 158°F to 167°F.
High melting Point Paraffin - 150 °F to 165 °F

Update - just found this and as I said all these temperature values need to be confirmed
Ron Coilman on Friday, May 06, 2005 - The tar will melt at 250-350 degrees.
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The location of the '26-'27 coil box could be a reasonable test case.
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Hot glue sticks may even be a better choice but the question is how high a melting point is needed
Most so-called 'hot glue' sticks are some kind of LDPE formulation (Low Density PolyEthylene) which will melt at 105–115° C / 221–239° F.
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Since wood starts to burn at a temperature of about 300 degrees Celsius (572 degrees Fahrenheit). all these choices could be melted down in the box

[Moxie26]

Frank...... Convince Ron Patterson of your suggestion and see if he approves.

[TRDxB2]

Frank...... Convince Ron Patterson of your suggestion and see if he approves.

In order to find a substitute its necessary to identify the parameters that are needed. Operating temperature range, non-conductive and ease of removable are the three that stand out. Just trying to spark some ideas that may provide and alternative.

[Moxie26]

If you're suggested alternatives are used to pour into the coil box, how well will your substitutes adhere to what is in the box already?..... And from road vibrations , and time , hot and cold cycles , have your newly re-poured area break away from the adjacent original tar with giving vibrations to the connecting wires causing them to break away?

[Scott_Conger]

There are no substitutes for either "the right thing", or the "right way".

Unfortunately, Model T owners for whatever reason, seem to be predisposed to do things "their way" even when the right way is clearly defined, works well, and has 100 years of real world success.

[Moxie26]

Scott .... Tell that to Frank, not anyone else. I use what has been recommended by Mr. Patterson and others who rebuild ignition coils properly.

[TRDxB2]

If you're suggested alternatives are used to pour into the coil box, how well will your substitutes adhere to what is in the box already?..... And from road vibrations , and time , hot and cold cycles , have your newly re-poured area break away from the adjacent original tar with giving vibrations to the connecting wires causing them to break away?

Good points... perhaps the most important.... "must be able to adhere to & be chemically compatible with existing substrate, not break down due to vibrations".

Please understand I am only trying to identify the parameters for an alternative - there may not be one. Unless we know what we're looking for we'll never find it.

Parameters
Operating temperature range (250-350° F), non-conductive, heat/cold tolerant, must be able to adhere & be chemically compatible with existing substrate (tar,wood), not break down due to vibrations, noncorrosive to wiring and ease of removable.

Other's? Available & at a reasonable cost?

[TRDxB2]

A source of supply Beacon Roofing Supply, Inc. looks like a National chain. even have a location near me.
store locator> https://www.becn.com/find-a-store
The Apoc Type 3 &4 melt packs weigh 50lbs each. Type 4 has a slightly higher temperature range
The Trumbull comes in 100lbs drum

[Moxie26]

Unfortunately, in this case , what was advertised in online catalogs did not reflect what they actually had in stock. I did not contact the companies that you posted, and they very well may have the stock. The good news is I did find locally and it will satisfy what I need now plus a little for later.

[J1MGOLDEN]

Type 3 was required for the 1926-27 coils sitting on the head and getting hotter than the earlier coils.

15 years ago, I had to get the whole 100 pound barrel of Type 3 like shown above.

That was from South America and evidently not allowed to be sent through the mail, as it is explosive when over-heated and burns good too.

The cost was $80 then, so it is about twice that or more.

Your best bet is to find a local roofing company that does large commercial buildings and will give you a few pounds.

Coil rebuilding is not for armatures, the coils usually will not work, after you go to all that work.

Your best bet is to send them to a professional rebuilder like Brent Mize or Ron Patterson and pay the shipping cost.

[jab35]

"Coil rebuilding is not for armatures, the coils usually will not work," I don't think anyone suggested using trembler coils, or coil windings for generator or starter armature rebuilds. Although armatures are frequently rebuilt, the OP wasn't doing that, he simply was seeking a source of tar for repotting trembler coils. jb

[Moxie26]

Wow, I just finished my second cup of morning coffee...... Jab35, thanks for observing the two previous poster's knowledge of armatures in ignition coils.... No wonder he has to send his coils out to be redone..... I am not looking here to advertise my coil rebuilding service, by word of mouth in my area being of coil service to local Model T guys has proved the best for both customer and myself....and on the other hand I have declined those who have habitually questioned will not be repeat customers.

[Been Here Before]

Maybe this was answered. Why can't roofing sealant in a tube or even silicon sealant in a rube be used for coil work?

[John kuehn]

I’ve also wondered if there is an alternative beside using tar. Yes I already know it’s what’s been originally used but maybe something is out there that would work just as well.

[Been Here Before]

""Yes I already know it’s what’s been originally used but maybe something is out there that would work just as well.""

Following this form, There are a few things done to the Model T by members that are not original as manufactured. So a substitute to the tar, enclosed in a box, enclosed in a housing that is not visible should not matter.

As long as the coil/condenser is sealed and water proof and insulated is not going to be of concern.

Bedsides, when was a show car judged by the way a coil was rebuilt?

[Scott_Conger]

As long as the coil/condenser is sealed and water proof and insulated is not going to be of concern.

Ask Ron Patterson, Brent Mize or others who rebuild coils just how fun it is to have to pry some kinds of goop out of a coil. Or for that matter, what some of those goops do regarding corrosion.

It sure as heck DOES matter

[Been Here Before]

From the forum 2012:

http://www.mtfca.com/discus/messages/25 ... 1338518904

"It sure as heck DOES matter"

If the original material is not available, out of production...then what? The model T has been kept alive for over 100 years because the shade tree mechanic was resourceful, and found that things can be substituted.

It seem that even in the aerospace industry ways to fit round pegs into square holes was not a problem.

Huston we have a problem but it is fixed...cardboard folders and duct tape.....

[Scott_Conger]

Having spent the bulk of my career in Aerospace Industry, I can assure you that when the right part, designed to be compatible with its assembly is available, you use it.

When TAR is no longer available, and a failed Model T coil shows up in a position where it will definitely lead to loss of life, then I'd be inclined to look for an alternative, but in any event, the alternative would need to be compatible to work properly. You seem to fail to grasp that not every goop that can fit into a little wood box is compatible, and some are downright deleterious.

If your best argument for not using the correct material in a coil, is to trot out a once-in-human-lifetime exercise in creativity, then I suppose there is no point debating it further. Reading your posts over the years, there is a history of there being a correct way to do something, and then there is your way...and that seems to go for pretty much ANY issue on a Model T. Neither I nor anyone else can possibly come up with a counter to the myriad of alternative ways to do things, that you imagine and espouse. I suppose that's what makes the world go 'round and In your defense, my experience with Model Ts shows that your thinking is the same as a great majority of T owners over the years. A great many cars that have come through my shop have no end of problems baked into them. What you chose to do to your car is none of my business, but advising others to follow suit is not productive or beneficial for the hobby.

And to think all of this is because, gosh, tar is expensive in 100# kegs. Seems that it makes more sense for someone to buy what they need and then to break it up and become a supplier to the hobby of small chunks of that 100# keg, but that's not nearly as fun as dreaming up alternatives to the real thing, I suppose.

[SteveD]

Thanks Scott, I learned a new word. Deleterious.

[John kuehn]

The right alternative is out there we just haven’t found it yet.

[speedytinc]

Arent there enough unrebuildable coils in anyone's collection to take the old tar from?
This is what my coil cap replacer guy does. Isnt the old tar typically recycled?

[Moxie26]

Frank .... Whatever amount of tar is chipped/removed extracting a bad capacitor is saved to be melted, along with new tar to replace the volume needed . Replacement capacitors are dimensionally smaller than Ford's original.

[Charlie B in N.J.]

I get the impression from reading here that it seems people are filling the extra space left by the smaller replacement cap with tar. I, and I’m sure many others here, fill the gap with wood. If properly fitted there’s no need for extra tar. I’ve never needed it. OK I’m not in the business having done about two dozen coils total but as I said extra tar was never needed. I spread plastic when I chip out and every bit is recovered.

[Been Here Before]

A quick review of electrical journals and books circa 1889 to 1919 indicate that along with tar, bees wax has been used for filling the void in induction coils. The tar and wax act as a moisture protector for the coils. One article gave the impression that the reason bees wax is not used was the expense. Now 2022, that may not be the case. This is coming from a friend.....

[Scott_Conger]

Yes, bee's wax may have been used in the past...I have zero interest in researching that...but not in a Model T and certainly not anywhere near a heat source.

Dr's used to bleed people to treat fever, and electric shock to cure impotence. Through the years, some advances were made in Medicine and a few in automobiles, too. While some small % may enjoy the shock treatment, they at least have the good sense not to advertise that fact.

[TXGOAT2]

Bees wax was widely used in older radio and TV sets to seal paper/foil capacitors and some RF coils and chokes.
I never encountered any wax in transformers. Transformers were potted in what appeared to be tar, very much like that found in Model T coils. The wax was often found to have softened from heat and dripped.