Today's fixturing tip

mitch

~ Elite 1000 Member ~
Joined
Jul 23, 2007
Messages
2,250
Thread starter #1
I was tasked with engraving over the bad pantograph lettering* on the base of a golf tournament trophy (oh, the glamorous life of a world-class artist!) and it was fairly large, hollow, and not particularly sturdy. While it was pretty heavy gauge copper, thickly nickel plated, its overall size made it likely to vibrate. The job wasn't big enough in scope or $$$ to justify turning a big filler block or pouring it full of some substance (like 20lbs of cerrometal, which nobody has).

My solution was to put it in a deep saucepan full of sand, with duct tape everywhere but the engraving area to prevent scratching. I also firmly stuck a wad of poster putty behind the engraving to further dampen vibration. It worked acceptably well and if it needed to be any firmer I could have added water, which would have made the sand more solid (but less amenable to turning the object to keep the segment being engraved at the top, and messier, too).

Here's the "slick" part: The white square you can see under the pot isn't paper or cardboard, it's the Teflon sheet that comes with a kit of Thermo-loc from GRS. With a little concentration on keeping it centered, it was much like turning my usual vise.

* There were two lines of type for successive years' winners. The second line was very lightly traced with a diamond drag point, but the first line was extremely heavily scratched? impressed? gouged? It displaced quite a bit of metal, but never broke thru the plating like a sharper tool would with that much force. I can't tell if the point was dull or broken, was spinning/rotating, possibly impacting, or how the heck this was done! It even looked like the point had a hollow tip, which left a tiny raised pip in the center sometimes where it was lifted off the surface. Nobody in the jewelry shop had a clue, either. Any guesses how that "E" was done???

IMG_5961.jpeg IMG_5960.jpeg
 

mitch

~ Elite 1000 Member ~
Joined
Jul 23, 2007
Messages
2,250
Thread starter #3
Looks like the aftermath of welding to me, no clue how, just what it looks like.
yeah, it does now that you mention it, except it wasn't a raised bead like a welded seam, it was down into the surface.
 

T.G.III

:::Pledge Member:::
::::Pledge Member::::
Joined
Jul 25, 2009
Messages
63
Location
Oregon
#4
Like there was no filler rod used, just heat.

pinpoint heat like a laser welder?
 
Last edited:

tdelewis

:::Pledge Member:::
::::Pledge Member::::
Joined
Oct 10, 2010
Messages
423
Location
Volant, PA 60 miles north of Pittsburgh
#5
I often use modeling clay for holding. The kind kids play with. You need to make a wooden box with a strip on the bottom for the vice to grip. I keep the box open on the ends. Force the clay into it and put the item to be engraved in the clay so that the edges are secured by bringing the clay up around the item. The only drawback is that after a time of working on it, it will warm up from the heat of your hands and will have tendency to start to move. Put it aside for a while with the item removed and when it is firm start working again. I always have more than one project going.
 
Joined
Dec 19, 2015
Messages
73
Location
Holland
#6
It looks like laserwelding! Very weird, must have been a very low setting to not mess up the plating.

The guy who did it probably also had a hard time keeping it secure. So then decided to use a laser to make the letters in stead of engraving.
 

mitch

~ Elite 1000 Member ~
Joined
Jul 23, 2007
Messages
2,250
Thread starter #9
Thanks, Martin! Apparently it was just done so BADLY it was unrecognizable. So, to recap:

An inexperienced/incompetent operator
+ Poorly set up, worn out, wobbly machine
+ Dull tool point
+ Worn template?
+ Chatter & dragging & skipping
= That mess.
 

Latest posts

Sponsors

Top