Hydraulic Die Forming Discussion Group

Bubbles- steel epoxy dies., Bubbles- Steel epoxy dies

Jon Olson
silverartisans@yahoo.com
Mon Oct 20 '08

I have found it difficult to get consistent results using "Devcon Steel Epoxy". I also found the product to be too expensive along with the bubbles created.
I have started to use iron powder mixed with "Devcon Two Ton Epoxy" and find that the bubbles persist. I've tried using a vibrator (vibratory polisher), on the epoxy separately and mixed with the iron powder. I've also tried adding 5% acetone as advised by Devcon with poor results. The opportunity to do anything is severly limited by the fast cure rate of the mix. Because of the extremely thick consistincy and the fast cure rate I cannot imagine the vacum machine being effective.

I would apprectiate any suggestions on bubble elimination.

Jon

Re: Bubbles- steel epoxy dies., Bubbles- Steel epoxy dies

Jeff Demand
Mon Oct 20 '08

Jon,

Slower epoxie, I've used some with a 6 hour pot life

Mix iron dust in one half and vac the hell out of it, or half in each but vac before you mix.

I've never tried it but some folks deal with bubbles using a pressure pot. Hit those bubbles with 4 atmospheres and they get really small really quickly.

Given the viscosity of epoxie (worse with added powder) forget the vibratory.

Jeff

On Mon Oct 20 '08, Jon Olson wrote
----------------------------------
>I have found it difficult to get consistent results using "Devcon Steel Epoxy". I also found the product to be too expensive along with the bubbles created.
>I have started to use iron powder mixed with "Devcon Two Ton Epoxy" and find that the bubbles persist. I've tried using a vibrator (vibratory polisher), on the epoxy separately and mixed with the iron powder. I've also tried adding 5% acetone as advised by Devcon with poor results. The opportunity to do anything is severly limited by the fast cure rate of the mix. Because of the extremely thick consistincy and the fast cure rate I cannot imagine the vacum machine being effective.

>I would apprectiate any suggestions on bubble elimination.

>Jon

Re^2: Bubbles- steel epoxy dies., Bubbles- Steel epoxy dies

Cynthia Eid
ceid@cynthiaeid.com
Mon Oct 20 '08

Hi,
AFter pouring, try putting the whole thing in the freezer. This works for RTV molds (Room Temperature Vulcanizing). I don't have a vacuum, so this was suggested to me, and it worked! the low temp. slows down the cure rate, giving the bubbles time to flost to the top and burst.

Warning: make sure to seal the mold well. I had a real mess in my freezer from one mold!

Cynthia
www.cynthiaeid.com

Re^3: Bubbles- steel epoxy dies., Bubbles- Steel epoxy dies

Dar Shelton
sheltech@yahoo.com
Wed Oct 22 '08

On Mon Oct 20 '08, Cynthia Eid wrote
------------------------------------
>Hi,
>AFter pouring, try putting the whole thing in the freezer. This works for RTV molds (Room Temperature Vulcanizing). I don't have a vacuum, so this was suggested to me, and it worked! the low temp. slows down the cure rate, giving the bubbles time to flost to the top and burst.

>Warning: make sure to seal the mold well. I had a real mess in my freezer from one mold!

>Cynthia
>www.cynthiaeid.com

Most of the ones I made were one sided and set up so that the mold had a backplate with a big hole drilled, which served as the pour hole when the mold was upside down for.... yep, pouring . I would tap tap tap the mixed putty's container and then pour it in a thin stream and watch the bubbles pop on the way over the brink . But I like the previous suggestions. Yeah, I patched some bubble holes too , on the resulting molds, heh heh.

Dar (busy busy busy packing for the Big Move , and trying to work as well . I keep telling myself "in a few months it will all be over ". no rest for the whiney until then !)

Re: Bubbles- steel epoxy dies., Bubbles- Steel epoxy dies

florent
Mon Nov 17 '08

>I would apprectiate any suggestions on bubble elimination.

>Jon

Jon, I think vaccum would work even if the resin is pretty thick, You should at least give it try. You ca also try to pour the resin into the mold from a distance of about 30 inches wich wil make a very thin "string" of resin an get most of the air out. Follow this link and you will see the technique I am taking about.
http://www.youtube.com/watch?v=NVvGc7VDFvc&feature=related
Good luck

Florent