A Sticky Tale
How many times has this happened to you? It’s happened to all of us.
We’ve got a bone fragment to be sliced very thinly for microscopic analysis or a sample to be shaved precisely for your Electron Microscope.
But, how do you hold those pesky samples?
It’s always useful to look at some applications in other fields to see if they might be useful for our engines. Sometimes, a small part is “unholdable” except by some adhesive. I admit, I’m a glue-aholic. I love VHB tape, Super Glue, all varieties of Loctite and chewing gum.
Last week I was watching Tom Lipton’s weekly offering on YouTube when he showed an adhesive used in laboratories, silicon chip fabrication and other tech areas. He attached a penny to a round blank, chucked it up in the lathe and proceeded to face it down to almost nothing.
The stuff is called “Crystalbond 509.” There are other formulations, but the 509 is the strongest.
Here’s my recreation of Tom’s experiment.
Here it is in person. Hard as glass at room temp.
After chipping off some small chunks.
A piece of 6061 on a hotplate with a few chips on top
When the aluminum reaches 250º F., the Crystalbond melts.
A penny.
Pressed into the melted Crystalbond. The instructions suggest building up a fillet around the edge. I had enough CB that it formed a fillet.
Next, the instructions specify a 20 to 30 minute cool down.
Then, mounted on the lathe.
A light facing cut. Carbide insert; 1000 RPM.
There was no indication of movement or loosening so I went for a .020 cut.
After a few face cuts and the copper cladding was gone, it became difficult to tell if I was cutting the penny or had gone into the aluminum. I stopped.
A quick hit with a heat gun and the CB melted and a cleanup in Acetone (recommended solvent) removed any traces.
I could have gone thinner as there was no movement of the part.
I can also see this for milling thin parts, etc.
This has earned a place in my adhesive drawer.
And yes, I've tried shellac. Not even in the same league.
A search for Crystalbond 509 should turn up multiple vendors.