cloudiness in casting

[pssherman]

I am getting cloudiness in some of my tube-in casts, 5 out of 16. I am casting braided stainless steel on sierra tubes and attaching/sealing them with thin CA. I let the CA dry overnight and do not heat them before casting. I can't control the temperature of my oven below 170F and CA doesn't like heat. Any suggestions on how to prevent the cloudiness from occurring?



I could shut the oven off when the display reaches 120F. That should keep it from getting to hot for the CA. Any thoughts?

 

[jttheclockman]

Are you sure the cloudiness goes all the through. Sometimes it is just around the casting tubes. I have seen that with silmar41. What resin are you using??

 

[pssherman]

Are you sure the cloudiness goes all the through. Sometimes it is just around the casting tubes. I have seen that with silmar41. What resin are you using??

The cloudiness is just around the tubes. I am using alumilte clear slow.

 

[jttheclockman]

The cloudiness is just around the tubes. I am using alumilte clear slow.

I probably can not help you with that situation because I do not use that type resin but from reading threads on here it does not like CA. I use Silmar41 as I said when doing my braiding castings. I also adhere the braiding to tubes with same resin and then top coat before I pour the entire blank. Just the way I have been doing things ever since I started casting braided blanks. Hope others can help you.

 

[KenB259]

The first watch parts blank I made had this issue, I then found out that CA doesn't play well with Alumilite, I did away with the CA and the cloudiness issue went away.

 

[pssherman]

The first watch parts blank I made had this issue, I then found out that CA doesn't play well with Alumilite, I did away with the CA and the cloudiness issue went away.

Then what can I use to overcoat the CA, I have 16 tubes with CA on them? Also, what can I use to adhere and seal braided sleeves, carbon fiber and denim to the tubes? Will modge podge or spray lacquer work?

 

[JohnU]

I think your problem is under mixed resin. Those 5 are probably the last 5 you poured with resin from the bottom and sides of the cup. It's true that Urethane and CA don't play well together but if degassed properly it will appear as air pockets and shiny spots. It can appear cloudy if not degassed but I think it would be in all of them and not just the 5. Usually braided material works better in Silmar 41 poly resin because it cures slower and gets thinner to penetrate the braids.

 

[RDHals]

I had similar issues at one time both the cloudiness and shiny spots John spoke of. I fixed the cloudiness with heat. Are you heating both your mold and the blank? That braided SS will retain the heat for a bit so heating to 120-140deg then turning off the oven should work. That should correct the cloudiness. For the shiny spots I switched from using CA to two part epoxy. Leave it over night to set. Should be good to go.

 

[Kenny Durrant]

I agree with the previous reply's. Something to think about trying is change the resin or change the glue. If you want to use the Clear Slow then use an epoxy glue to glue the braid to the tube. That's what I do with no problems. To bring up mixing again that is a big deal. Be sure to get the bottom and sides. Not mixing properly is just like not getting the A and B sides weighed correctly. That being said if your going to be light with one part be a little light with the A side. I'm not saying do it on purpose but be sure not to go over on side A.