MTFCA Forum

Got a question for all those who have mag horns (something which I don't have)....what size is the screw that holds the bell to the vibrator housing and are the screws that mount the horn to the bracket a bit longer or are they the same length. I need both the thread size and the length. Can't find any mention of them in any of my books, so I thought I'd ask here.

The next question is....are the screws for the electric horn a different size from those used for the magneto horn?

I hope someone will have a better answer than I. I looked at the pieces I have. One made by Ames has 1/8" rivets. Some pieces have .140 dia holes and some have 3/16 holes. 1 Horn has .281" long #8 round head screws with square nuts like erector set screws. No screws for the bracket. Another has #6 round head screws .218 long with hex nuts. The bracket screws are 7/16 long and have oval heads. Both of these have a triangle and Made in USA stamped in the back. The latter probably has been tampered with. Maybe both have.
I'm sure someone has original, un-tampered with horns and can verify what is correct. My guess is that the fasteners for the horns may have evolved over their manufacture.
Best of luck finding the truth.
Rich
P.S. You may have seen this:
http://www.mtfca.com/discus/messages/70 ... 1505860067
Those look like the #6 screws I have.
Also, Bridgeport Brass in 1915, HECO and possibly Briggs and Stratton made mag horns for Ford according to another thread.

Richard, do you think that originally the horns were riveted together and at some point had the rivets removed so they could access the diaphragm (maybe to either repair and or replace)? Would you say they're a 6 32 or an 8 32? There is also a 40 thread count for both of those...just wondering which it might be.

This is what I've got so far.

So any information as to the size of those terminal screws would be a big help....also would like to know the size of the Adjustment Screw as well.

Hi Martynn,
Three horns had #10-32 terminal screws. I only checked one diaphragm screw and it was #12-28.

Ok, not sure of the lengths though, so I made a guess.

The terminal on my mag horn is 8-32. The three screws holding the bracket are definitely longer than the other three. I'd show a picture if I could find it. I'll take Rich's word on the adjusting screw. I don't want to take the horn apart again.

Here is what my vibrator plate and screw measured. The other two look the same looking down inside. The slot in the adj. screw is about 1/16" wide and deep. Also, the small diameter of the Horn bell is 1.83 where it goes into a flange 1.88 dia. x 3/8 high. The flange is bent 90 degrees from the housing that bolts to the diaphragm and rear housing. I'll leave this horn apart if you need anything else.
Rich
Looking Good.

Here it is. The entire length is 8" inside measurement of both pieces. The large end measures 3 1/16" dia. (average) It is spot welded in 4 places or maybe 5. It is 1/8" to 3/16" (varies) short of the radius in the end flange. The left flange is also 3/8" and has ford script. The painted one is similar with no Ford script. The right one is an AMES (PAT APLD FOR) and is 3/16 long. Smaller spot welds. Only one of which is still attached. You can see a remaining rivet in the Ames. Notice that the two lower flange plates (Ford & Ames have one larger hole (5/16") in place of a regular screw hole. The 3 screw holes for the bracket are 1 1/2" apart in all of these while the other holes are 2 3/16 apart. The Ford script flange plate has an additional hole 1 1/2" from the last bracket hole. The black horn bell and flange only have the holes where you show them in your drawing.
Whew!!!
Rich

Rich, how about this? Still don't know what that larger hole is for or which side it's on either.

I'm wondering if there isn't a way to "tune" one of these horns to something a lot less annoying than they sound now

Just get a mechanical horn. https://www.youtube.com/watch?v=MHZCpzrsdEA

That's looking darn nice. I haven't seen the Ford script there. On My last picture it is near the lower left corner of the enlarged view of the script. It's about on the housing bolt circle. The spot welds don't actually show. I'm not sure if showing them would be confused as something else. As for the sound, my first one with a weak magneto sounded like a coil buzz. My better one is louder and sounds like a variation of the bulb horns. Steve's solution is more satisfying and the action of it or a bulb horn is visually nice. However the mag horn sound is original and some will like it for that reason.
As for the 5/16 hole, I wondered if it could be a different terminal location. I have a diaphragm with a 5/6 hole in that location and a second one opposite side (symmetrical). It doesn't have an adjusting screw in the middle or even a hole. Another just like it with a just a hole in the center. I haven't seen a bell flange with a hole there though.
As often happens more question than answers. I'm sure there is more wisdom out there but.....
Rich

I just discovered this magnet mounting goes with the Ames flange and probably the last diaphragm I mentioned. At the bottom of each piece you can see the remains of a rivet and the disturbed hole it was pulled through. The windings are very different and the rear cover would be larger than those previously discussed. Perhaps something like the Heco horn. I don't have any other parts to it. The single wire may go to a terminal through the 5/16 hole. Which says it grounds thru the bracket. No help for the illustration but if others are following along it adds to the mysteries.

Just get a mechanical horn. https://www.youtube.com/watch?v=MHZCpzrsdEA

I have one Steve, you saw it when last you were out here, it is on the drivers side panel just ahead of the arm rest, but when you last tried it, it didn't work (had to replace the jam nut on the tuning screw)....anyhoo, yours sounds like your adjustment is a wee bit too tight, mine actually makes an aaah-ooo-gah sound when you mash down on the plunger. Back yours off one half turn and see what it does then, if too weak, try a wee bit tighter and keep experimenting with it until it sounds right. By the way, you may want to make a tool for tuning it (if you haven't got one already), it's basically a cheap hollow spin tight, that I drilled a hole through for a really long screw driver....makes it a lot easier to tune the horn.

Rich, looks like they've put the windings on their diaphragm and that clacker (riveted long strip) translates the vibrations down through the brackets making the diaphragm into a soundboard, the cover is supported up off the diaphragm on those uprights....would love to see the cover though, would really love to see how this thing works.....I think I may need to make another drawing....every time I think something is really simple to draw, up pops something else that proves me wrong, well...fun never quits ya know.

I don't think it's the diaphragm but an additional plate. I was assuming the diaphragm at lower left went with it but I'm not sure how it would assemble. All the holes line up as does the diaphragm just like it without a center hole. That one was sandblasted like the flange and coil plate. Perhaps they went together.
Curiouser and curiouser.

Rich, I don't know, it has a raised center portion, yet has no contact part with a diaphragm to make the noise, to me this suggests that, that raised portions acts like a diaphragm only instead of vibrating it amplifies the sound from that clacker on the back of the windings bracket. You might want to assemble it and see....if it makes no noise, then assume it needs that diaphragm...but a diaphragm would to be insulated from the both the plate and the housing (the gaskets) to vibrate. Would really love to see this thing or one like it, to fully understand how it works.

Another maker of T horns was General Industries in Elyria , Ohio . They also made a lot of horn buttons and assemblies. Horns and parts are sometimes marked with GIM or GMI . I have a model A horn made by them and it is made different than the others, so I would expect the T version to be different, also. Just some added confusion.

Here is an Ames Mag horn for sale:
http://www.2040-parts.com/vintage-ames- ... -i1427751/
The front flange is much the same as the Ames flange I have. This may be what the bell and cover looked like on mine. It has a terminal where mine has a large hole. Also a terminal about 120 degrees away. New screws instead of rivets.
This one on Ebay just claims "Ames horn". Ames also made a battery horn from what I can tell. Looks like just the one terminal here:
https://www.ebay.com/itm/164267344872?h ... Sw5ERe-Xmg
Also screws rather than rivets.
This one claims "Ames H14 6V works" Bat? (old eBay ad)
https://www.bing.com/images/blob?bcid=TywKF71Z0ZMDUA

I see no Ford script on the Ames horn. I see that the open ends of the Ames magnets are not near the flanges where a vibrator plate would be as are the open ends on the other mag horns. They are more near the back of where a cover would be. Without something for them to make and break contact with I don't see how is could work. That would allow the mounting plate end to vibrate some also. I could imagine it pounding on either the vibrator plate with the holes or the one without the holes and making some sort of racket. There is about .021" between the rivets and the vibrating plate.
I'm not sure how many Ames mag horns were made. There isn't much out there on them. I find it interesting that all the mag horns have the same basic housing screw pattern regardless of who made them. I don't have enough battery horn info to know but it seems they all have a different spacing.
With the few pieces I have it's hard to know more. Someone does but may not have seen this thread. I have learned a lot and hope it may be of some help to someone. I'm glad you brought it up so we could explore it this far.
Rich

The script is hard to see in the previous pics. This flange is by itself with no other parts but identical to some without the script. It is true that I see NO Ford script on the parts I have or the other horns on the web.

That's a great question. In a perfect world it would be at the top. This flange has an extra hole allowing the bracket to be placed in two different locations. Why? I don't know. The location of the script would depend on which holes were used. I'm not sure if the different brackets allow the horn to mount in the same orientation or not. Perhaps a specific bracket was used during the time the Ford logo was put on. Each question brings up more questions than answers.
Cheers!
Rich

P. S.
After some more thought, if the horn is mounted like this with the bracket you show, the script would be at the lower side. Straight down or at 4 or 5 o'clock Maybe all mag horns used that bracket. I have a non script one that mounts on the water outlet and the horn is wire in place to it. No Idea if that was a correct bracket for it. The script then would appear at 2:00 or 3:00 as I see it.

Ok Rich, I've done a bit of redraw to make things appear as they should if you were going to mount the horn (I had to change that because everything I draw is based upon how it goes onto the car). Anyhoo, how about this one? Also gave it a Rev number because every iteration was beginning to look more like an actual drawing than an inquiry layout.

I'm calling it a Ford Magneto Horn, because I don't know who makes it. If you know please let me know and I will make that change.
Probably like you I've got anywhere from 3 to 6 drawings all going at the same time, what determines which gets finished is whenever I get the information I need or have asked about....sometimes though, I just plain forget to look and see what folks (like you in this instance) have posted, so when I do, I scramble to get it done, even if means re-laying out my original concept....and since you're an artist too, you know how well such ideas are received, especially after you've spent a goodly amount of time doing it the first bloody time.

I always enjoy seeing these. I makes me wish I still had access to AutoCAD. I think the Ford script would look larger and the horn bracket smaller. The large hole should be near the script now. The bracket holes which are closer together would also rotate into that position. Not knowing what that large hole is for, it might affect the terminal arrangement. Hopefully, someone has a complete script horn to see.
Have fun with it!
Rich

Rich, lol, everything I do is fun no matter how many changes I've got to make (the major reason I chose this field of work over engineering, in the first place....what I do is fun and the best way to put that is "Fun never quits"). The quest is to make it as correct as possible, you're right, we both won't know unless somebody with one of these dratted horns in original condition can shed some much needed light on the subject, but until then, we do the best we can and let that balloon fly...until it doesn't. . Then when some other information comes to light, of course I'll make those changes to the drawing.

So, I went back and reconfigured the hole positions and the bracket, also enlarged the logo a tad and I hope this is closer to what it is supposed to be.


The unfortunate part is that all my drawings are in CYMK 32 or RAW 64 bit, the forum won't accept anything that large, so the best I can do is RGB 24 bit, which by definition means some detail loss, I try to mitigate that some though, by changing line weight densities. I'm not using a CAD program per se, it's a Graphics Suite, which can do everything from imitating water color through oils and pastels if I really wanted too and make animated backgrounds from them as well, but since I have no use for those options, I never use them. Although there are times when I can see the need for a good CAD program like Solidworks or even AutoCAD, but even using my graphics program I can dump to a 3d printer (if I had one) and even a laser engraver Co2 or Jag (also if I had one), but I don't, sooo (like it says in the bottom left hand corner).

Hi Martynn,
I remeasured this for a different post and realized the thread is actually 1/4-32tpi. .240 seemed closer to #12 but it is in fact 1/4 on this.
Rich

Rich, hmmm....ok.