Conner Prairie Horn Class Part 1

[Larry Pletcher]

Art DeCamp's horn class ended Wed. noon, and I'mback with photos.  The class was outstanding.  Art is as good at teaching as he is at horn making.  The class had 11 students making screw tip horns.  Art brought 3 lathes, each set up for a particular operation. 

The first pic shows the horn as it comes out of the hot oil.  The form for shaping the end is also the mandrel that will hold the horn in the lathe. The lathe speed is quite slow.  Jeff Bibb is shown doing a nmber of the operations.  In most cases if it isn't Art in the photo, it's Jeff.












Turning the tip:






Turning Plug:










Turning final shape:


Part 2 will deal with the tip.
Regards,
Pletch

[eseabee1]

WOW braver then I am turning a horn in a lathe if I did that I would get hurt for sure ...but looks like fun

[Nate McKenzie]

These are great pics. Do you have any more. This would make a good tutorial.

[Larry Pletcher]

I don't understand why the base of the horn is being turned on a lathe.  What's being done there, and how is the horn held in a tapered plug?

Hi Daniel,
After the horn comes out of the oil and is formed on the tapered wood plug, the interior is round but the exterior isn't because of a wall that varies in thickness.  The base-turning step is to produce a uniform wall thickness.   The tapered wood plug serves two purposes.   It forms the horn but also has the opposite end turned to fit on the 3-jar chuck.  With the horn still attached to the plug, it was installed on the chuck and turned very slowly.  Art guesses about 100 rpm.  The cutting stopped as soon as the tool was cutting all the way around the horn.   Our goal wasn't to thin the horn, but only to get uniform walls.

The horn is held only by the friction fit on the plug.  If the angle of the plug and the horn was pretty close, the horn didn't pop off.  On a few the horn fell off; in that case a damp piece of paper towel was placed between the horn and the plug, and the horn was pressed on.  This was a short process because very little had to be removed to get the walls even. 

Turning the neck went well.  Here after drilling the neck hole, we taped it with a 1/4" tap.  We left the tap in the neck and chucked the tap.  Then we turned the neck to a uniforn diameter to match the die used.  Remember that the rpm was very slow.  It took a variable speed motor to do this.

The explanation here is from a student's perspective.  I hope Art will clear up anything I may have said.
Regards,
Pletch

[brokenflint]

Larry   Are the lathes used homebrewed by Art?  they look to be really short bed lengths if I'm looking at them right, the photos showing the trueing of base plug end.

Broke

[Randy Hedden]

Larry   Are the lathes used homebrewed by Art?  they look to be really short bed lengths if I'm looking at them right, the photos showing the trueing of base plug end.

Broke

For the end turning of the base of the horn, the headstock has to be mounted at the end of the bed or a gap bed lathe has to be used because the horn turning in the chuck needs more swing room than the normal small lathe has.  You cannot turn the horn on a regular lathe unless it is a large commercial lathe with a lot of swing capacity.

Once the horn has been rounded you might as well face off the end of the horn while it is in the lathe so it is square and perpendicular to the body of the horn.  If not you would just have to sand/file the end of the horn flat/perpendicular so might as well do it while it is on the lathe.  Of course, if you do several horns you will need to replace the rounding form because it will get all cut up in the process.

Randy Hedden

[Larry Pletcher]

Once the horn has been rounded you might as well face off the end of the horn while it is in the lathe so it is square and perpendicular to the body of the horn.  If not you would just have to sand/file the end of the horn flat/perpendicular so might as well do it while it is on the lathe.  Of course, if you do several horns you will need to replace the rounding form because it will get all cut up in the process.

Randy Hedden

Randy,
I should have mentioned that.  After turning to a uniform wall thickness, we faced off the horn edge before removing the horn.    As the plugs become deformed because of repeated facing off, Art turns them smaller and eventually replaces them with bigger ones.

Your comment on the large swing is also correct.  Art's lathe for turning the butt end has the variable speed head stock reversed 180 degrees so it sticks off to the right of the original position.  The lathe used to turn the plugs was a normal lathe, but we didn't use all the length or the tail stock.  The lathe used for turning the screw tips was a small Atlas metal lathe.

Regards,
Pletch

[Tim Crosby]

 Nice writeup Pletch.

 Tim C.

[Randy Hedden]

Randy,
I should have mentioned that.  After turning to a uniform wall thickness, we faced off the horn edge before removing the horn.   
Regards,
Pletch

Larry,

In retrospect, I guess I shouldn't have butted in and answered a question posed to you, but I have much the same setup using an old collet lathe with the head turned backwards on the ways and a small 6inch Atlas metal lathe.  I have never had a good wood lathe with a chuck on it so I just improvise.  When cutting a York county screw tip horn, I cut the two incised lines at the butt of the horn at the same time that I cut the butt flat and perpendicular.

Randy Hedden

[Leatherbelly]

 Ahh,
  No wonder you guys can pound these horns off in a week! Takes me a week with a file and a scraper just to get a rough horn shaped. Great thread.

[Randy Hedden]

Ahh,
  No wonder you guys can pound these horns off in a week! Takes me a week with a file and a scraper just to get a rough horn shaped. Great thread.

LB,

Even if you have a couple of lathes set up, you still have to do the scraping and forming of the horn by hand.  The lathes only come into play when you are doing the last processes to the horn.  Years ago I did all my horns by hand, start to finish, and even now I do certain parts of the building by hand as it is sometimes quicker and easier than using the lathe.  There is nothing in building a powder horn that can't be done strictly by hand and with a little experience it can be done in short order.

Randy Hedden

[pathfinder]

Leatherbelly,A week? what'ya do,work 24 hours a day? Takes me a week to decide where to start! Been workin' on one fer year! Should have it done by the Tri-centenial!