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Tuckerfan
11-24-2012, 05:18 PM
Ever have one of those pictures that you've looked at a thousand times or more, but failed to notice certain things about it? I was staring at a photo of parts of the original mold for the Tucker's horn button, when it suddenly occurred to me that I hadn't the faintest clue as to how it would have been done back in the '40s. I know how one would do it now, with a CNC machine, but back in the '40s, with only manual equipment? I don't know.

Here's a shot of the mold, showing the Tucker crest.

https://lh3.googleusercontent.com/-GFsmi58EPaE/ULE2UiZnMhI/AAAAAAAAEIw/3SeVVb20pnE/w248-h248-p/horn%2Bbutton%2Bmold%2B01.JPG

Here's the back side, showing that it was machined out of bar stock

https://lh6.googleusercontent.com/-w8_hpX_PXfE/ULE2Y6AUJFI/AAAAAAAAEI4/xXCd2bMt5P4/s500/horn+button+mold+02.JPG

The front of it is fairly elaborate and detailed, with the crest following the contours of the curve of the mold. So, any clues?

Errol Groff
11-24-2012, 05:36 PM
I will take a guess at a hand carved model and a duplicating head on a B'port type machine. A tracing stylus in one spindle and a power spindle in the other.

John Stevenson
11-24-2012, 05:41 PM
Something like an Alexandra 3D engraver, bit like a standard pantograph engraver but the head can follow a 3D pattern.
Patterns would have been done 6 to 10 times size as any errors on the pattern do nor show on the mould.

bob ward
11-24-2012, 06:02 PM
How cool is that? An original piece of Tucker factory tooling!

Edit. I think the penny has just dropped. Hence your recent post on melting aluminium? You probably know this, but wax investment is the way to go to accurately reproduce a detailed piece like this. Lots of info at alloyavenue.com or its predecessor backyardmetalcasting.com

Tuckerfan
11-24-2012, 06:18 PM
Its about the only piece left, too, I'm afraid. The original dies for the cars were made out of Kirksite (these were intended simply to be used on building the pilot cars and would have been replaced by more conventional material) and their whereabouts are uncertain. A couple of gentlemen bought up most of the dies and the incomplete bodies and parts, intending to build more cars, but never built more than a couple. The bodies and the tooling sat outside and were damaged by the elements. The final disposition of the remains isn't entirely clear. Some were sold, and its assumed that the rest were crushed, but the folks who actually know about these things have the annoying habit of being rather tight lipped about it all.

Paul Alciatore
11-24-2012, 06:19 PM
I do not see what it is in the second photo that "shows it was machined out of bar stock". Although the explanations above are certainly possible, I would suspect it also could have been stamped like a coin.

oldtiffie
11-24-2012, 06:26 PM
Many coinage dies were cut by hand which required extreme patience and skill.

Banknote printing plates were similarly cut - but they were more difficult as all colors in the note had to have a seperate plate and all plates had to be correctly "registered" in relation to each other.

Filigree work is similar as regards hand and eye skills and co-ordination.

http://en.wikipedia.org/wiki/Filigree

Tuckerfan
11-24-2012, 08:19 PM
How cool is that? An original piece of Tucker factory tooling!

Edit. I think the penny has just dropped. Hence your recent post on melting aluminium? You probably know this, but wax investment is the way to go to accurately reproduce a detailed piece like this. Lots of info at alloyavenue.com or its predecessor backyardmetalcasting.com
No, I hadn't planned on making castings of that. It's a little more complicated than my skill set, and I don't have access to the necessary tooling to be able replicate it (I'm certainly not about to attempt to hand carve it). Pouring aluminum has got me thinking about making more sophisticated things than I've been doing lately, which is what got me thinking about how they would have made that.

I am going to try and replicate the Tucker ashtray given to dealers. There weren't that many made, and they generally sell for $1K+, which is way out of my price range.

http://1.bp.blogspot.com/-ejPXXvnezNc/TdKnRBZFHKI/AAAAAAAAAW8/CyBd_VrVpI8/s1600/Tucker+ashtray.jpg

I've got a model of the car that's about the right size that I can use to make part of the mold, and much of the rest can be easily machined out of a block of wax on the manual mill we have at work. The tedious part isn't visible in that picture, but the car is on a bricked road (to represent the track at Indy), and the bricks are staggered, so I can't simply do one cut along the short section and be done with it. Still, it should prove an interesting challenge, and if I do it right, I might even be able to make a little extra money selling them.

JoeLee
11-24-2012, 08:45 PM
I'm going to say that back in the day it was probably hand engraved / carved after the basic shape was turned and the face concaved or rounded.
Then it was used to either stamp or cast off of.

JL......................

Tuckerfan
11-24-2012, 09:26 PM
The horn button was cast or injected in plastic as I've seen photos of them and have a replica which was based off an original horn button (I don't know if it was made using that piece or not, and unfortunately the gentlemen was selling them has passed away, so I can't ask him about it).

A.K. Boomer
11-24-2012, 09:50 PM
look at it with a really good magnifying glass and you will see how it was made..

Tuckerfan
11-24-2012, 10:16 PM
Well, I don't have access to the piece, only a photograph of it.

Bill Pace
11-24-2012, 10:26 PM
I have been home casting for a number of years and I believe that would green sand cast quite nicely. I recently finished a project that was a bit similar to this - a no longer available name badge.

I have just finished up a restoration of a Sheldon lathe with the "Sheldon" name plate missing. I asked on the yahoo Sheldon site for info or pictures of the item, thinking if I had a pic and the dims I might could make up a casting. As typical on most forums, I quickly got help, several pictures and best of all, an offer from a member to send me the plate off his lathe to see if I could use it as a pattern or just use it to try to copy. The plate arrived and --- uh oh! its a thin stamping, much to thin to do a cast from. But with a little head scratching I loosely attached a 3/16" thin piece of wood to the back side and carefully trimmed to match the edges of the plate - I could cast this... I had 2 suitable flasks so I molded up both and got 2 really nice reproductions. Using these 2 and the original and the 2 flasks again, I got 6 more nice pieces. (there had been several guys on the forum wanting copies) The detail a good sand will reproduce is amazing - I once saw a picture of a piece that had picked up the guys fingerprints!. (I use Petrobond oil sand)

Hers a couple pics---

This is the original (in the center) and the 2 copies from the first pour just before close-up. The back side has 2 tabs about 1/4x1" for attaching to the lathe, I just pushed them into the sand and the imprint will come when I fill this with the sand.

http://i22.photobucket.com/albums/b301/pace1980/Sheldon%2013x36%20lathe/SheldonNametag006.jpg

This is my pouring 'station' - propane furnace, the 2 flasks closed up and ready to pour, the misc lifting tools, slag spoon, etc and a couple muffin tins for excess.

http://i22.photobucket.com/albums/b301/pace1980/Sheldon%2013x36%20lathe/SheldonNametag004.jpg

A close up of the front and back of the replicas

http://i22.photobucket.com/albums/b301/pace1980/Sheldon%2013x36%20lathe/SheldonNametag.jpg

All of them lined up with a couple painted - getting the red paint in there was harder than making the pour! The original is on the bottom with the thin piece of wood used on the back side.

http://i22.photobucket.com/albums/b301/pace1980/Sheldon%2013x36%20lathe/SheldonNametag008.jpg

A.K. Boomer
11-24-2012, 10:41 PM
Well, I don't have access to the piece, only a photograph of it.


oh - sorry. --- my bad...

Bill Pace
11-24-2012, 10:45 PM
Well, I don't have access to the piece, only a photograph of it.

OOPS, my bad too - guess you were typing while is getting the pics in -- oh well enjoy the pics anyway...

duckman
11-25-2012, 01:26 AM
That is what is called a hob , molten metal is poured into a mold and while its still semi molten the hob is pressed in and you end up with a cavity to make your mold from, used to work at a mold co. where we poured at least 1 ton of BECU every month.

John Stevenson
11-25-2012, 08:31 AM
I have been home casting for a number of years and I believe that would green sand cast quite nicely. I recently finished a project that was a bit similar to this - a no longer available name badge.

I have just finished up a restoration of a Sheldon lathe with the "Sheldon" name plate missing. I asked on the yahoo Sheldon site for info or pictures of the item, thinking if I had a pic and the dims I might could make up a casting. As typical on most forums, I quickly got help, several pictures and best of all, an offer from a member to send me the plate off his lathe to see if I could use it as a pattern or just use it to try to copy.


Nice work Bill.
I have done quite a few plates now on the CNC, some as just one off's but quite a few to be used as patterns for casting.

Working on a Foden badge at the moment, normally they are not rare but they used a certain design for one model that was different to the rest and the collectors know this. Got some decent photo's so not too bad, just time consuming

lynnl
11-25-2012, 10:03 AM
Bill, I'm curious about using a copy of a copy as the pattern for still another pour. Were the final copies poured noticeably smaller?

I realize that for something like a badge or emblem, where fit with another component(s) is not an issue, shrinkage doesn't matter as much.

Tuckerfan
11-25-2012, 11:38 AM
OOPS, my bad too - guess you were typing while is getting the pics in -- oh well enjoy the pics anyway...

No worries. I've got a number things I'd like to cast and I never would have thought of doing them green sand if you hadn't made your post, so I appreciate the info.

Bill Pace
11-25-2012, 12:10 PM
Bill, I'm curious about using a copy of a copy as the pattern for still another pour. Were the final copies poured noticeably smaller? I realize that for something like a badge or emblem, where fit with another component(s) is not an issue, shrinkage doesn't matter as much.

Well, I didnt even think of that :o Of the guys wanting most of the copies, most were only gonna use one as a wall or desk mount, so that wouldnt be a factor. Then, the fact that it is quite small, brings the shrink factor down a good bit. I dont even know from which batch mine came from, but the mounting 'ears' on the back were a bit short for the mounting holes, so there was some shrinkage - Ill have to do a couple measurements and see. I was/am only gonna do that one batch - was a bit of a hassle....

Evan
11-25-2012, 05:46 PM
I studied jewelry making at the College of Arts and Craft in Berkeley and have made quite a bit of jewelry in the past. That piece was made using a turned steel slug on which are silver soldered German silver (copper/zinc/nickle) investment castings of the parts of the coat of arms. Looking at the image it is apparent that there are slight differences in colour that give away the process. By enhancing the colour you can see how it was made. The steel parts are very bluish, the silver solder is yellowish and the German silver is whiter/slight bluish. The silver solder tends to spread out around the parts and is wiped off while hot using a wad of wet asbestos as the parts are clamped in place with spring clamps while soldering. That spreads it a bit further.

The various parts are soldered on using different melting grades of solder so that the earlier parts do not melt loose as the later ones are placed. After soldering there will be some additional mechanical cleanup with fine files and other tools to get rid of excess solder. There also may be some extra hand work required to correct the draught on the parts.

http://ixian.ca/pics10/tuckerbadge.jpg

tdmidget
11-25-2012, 11:38 PM
I do not see what it is in the second photo that "shows it was machined out of bar stock". Although the explanations above are certainly possible, I would suspect it also could have been stamped like a coin.

You are right , Paul. The vertical marks from the stamping are not all removed by subsequent machining, quite visible in fact.

Evan
11-26-2012, 12:25 AM
It isn't machined. You can see where there is a space between the cast parts on the right that wasn't filled with solder.

http://ixian.ca/pics10/tuckerbadge2.jpg

Peter S
11-26-2012, 08:12 AM
Toolmakers make this sort of thing for breakfast ;)

Not that I know how this one was made....

But as has been said, a 3-D pantograph (Deckel etc) can be used to make something like this - but also tracer mills have been around for a fair while, see attached pages from a 1951 Cincinnati Milling Machine Treatise. In the 1980's our patterns for both pantograph and tracer mill were made from what looked like epoxy.

Another possibility where detailed tooling wears out, was hobbing. A 'matrix' is made (on pantograph) and hardened, then used in a very powerful hydraulic press to 'hob' the actual tooling. It only takes a few seconds to do the hobbing, then you have to machine the hobbed piece of tool steel where it has been deformed (e.g. all the turned part of Tuckerfans example), then harden and polish etc. This way you can keep making replacement tooling comparitively easily as it wears out. This was a common method where I worked and was still effective even in the era of spark erosion.

http://img.photobucket.com/albums/1003/PeterS/Cincinnatipg590.jpg

http://img.photobucket.com/albums/1003/PeterS/Cincinnatipg591.jpg

http://img.photobucket.com/albums/1003/PeterS/Cincinnatipg618detail.jpg

http://img.photobucket.com/albums/1003/PeterS/Cincinnatipg618.jpg

http://img.photobucket.com/albums/1003/PeterS/Cincinnatipg619.jpg

Evan,

Normally any sort of tooling for moulding is hardened steel (unless you are making just a few hundred items....errrr....like Tucker I guess).

BillTodd
11-26-2012, 08:41 AM
Here's a youtube video of making of a coin stamper, your button, or the mould/stamp to make it, would have been made in a similar way

http://www.youtube.com/watch?v=QrtCcXXNcGA

Evan
11-26-2012, 02:25 PM
Keep in mind that this is the master for a plastic mold, not for casting metal. The negative could easily have been made from any low melting metal alloy cast on the master. Antimony/Lead would work.

Boden
11-26-2012, 06:05 PM
I've spent quite a bit of time in England doing casting. If I was going to make one of those I'd make a simple lost wax mold and pour it. Then do the detail work cleanup after and then some polishing to remove any grit or flash.

Peter S
11-26-2012, 06:41 PM
Evan,

My comment about hardened tool steel referred to any plastic molds, normally all tooling is hardened. I wouldn't be surprised if this button was compression molded from thermosetting powder?

Evan
11-26-2012, 08:08 PM
It looks like cast parts soldered to the slug to me, especially with that gap on the right. I have done a lot of silver soldering and it looks very much like flowed out solder around the pieces with the colour difference to boot. This very possibly could have been a prototype for a very limited run. It does not look machined. It is also not good a good enough quality image to judge any machining marks. There are numerous jpeg artifacts that look like tool marks but aren't.

Because of the time period the button would have been made with phenolic so it would be thermosetting. Whether from powder or not is impossible to guess.

On second thought, perhaps not. They did use acetate then as well as phenolic. I have an original B17 yoke badge that is made from a clear acetate with painted back.

Tuckerfan
12-01-2012, 12:50 AM
Its not the best pic, but it was the easiest one I could find that shows an authentic Tucker horn button.

http://tomszone.com/Tucker%20Horn%20buttons%20cropped.jpg

As you can see it, along with the buttons it sat on, were made of a clear plastic that was later painted.

Evan
12-01-2012, 02:55 PM
That appears to be the same technique as the B17 badge.

http://ixian.ca/pics10/b17.jpg

Tuckerfan
12-02-2012, 04:15 PM
Found a pic of the mold at a slightly different angle, and if you look at the lower left side, you can see another place where a section of ivy wasn't tacked down, so its clear that Evan nailed it.

https://lh5.googleusercontent.com/-IUoLBvF-DAw/ULu1yLR2j2I/AAAAAAAAEKg/HihwCC5-iuM/s500/horn+button+3.JPG