On Wed, 20 Dec 2017 14:04:26 -0700, Bob La Londe
wrote:

On 12/20/2017 1:54 PM, wrote:
On Wed, 20 Dec 2017 12:54:10 -0700, Bob La Londe
wrote:

I'm not sure how this will work out, but I am going to try it. This is
strictly a fun personal project to find out.

The goal is a two sided embossing die for paper. One is a positive and
the other is a negative. I know I could just have one made cheap by the
guys who make notary stamps, but this one will have a 3D image of my mom
from a painting my grandmother did when she was dating my dad. I want
to make it myself.

Here is the process I am going to try.

1. Machine pocket with all the features raised at the bottom of the
pocket. 2hrs apx

2. Spray it with UMR.

3. Make a backing plate the size of the pocket with some screws set in
it for anchoring.

4. Fill the pocket with casting resin, and place the backing plate into
the resin.

5. Pull resin plug at listed demold time and set aside. 10-15 minutes.

6. Machine away side walls of aluminum positive plate leaving just some
holding tabs.

7. Remove positive from bar stock and clean up on bench sander.

8. Wait 24 plus hrs for full cure of resin.

9. Mate the two halves and mount them for pressure turning on the
lathe. Turn the resin plug down to match the aluminum plug.

10. With halves mated mount on spring plates.




Is the resin really that durable? I'm impressed. What kind of resin
are you using? I don't have any experience with the stuff but your
post has me intrigued.
Eric



I don't know. I'm using some polyurethane resin called Quick Cast from
Tap Plastics called Quick Cast. I'll find out. I recently did some
other casting with AlumiRes RC3 from Alumilte for a totally different
application and it turned out ok, but only time will tell. Upon
thinking of it I have a couple other resins coming (slower demold time
and thinner pour viscosity) for another application. I may just cast
mating plates with all of them before cutting out the aluminum plug so
if one doesn't hold up I can swap out another.

I actually started this project back in 2016, but time and paying work
got in my way. I recently machined some crankbait molds to be used with
casting resins. They worked out pretty good, and it got me back to
thinking about this project.


I am really looking forward to finding out how your project works out.
Eric