# How to make sure molded silicone rubber adheres to the ABS mold?

For one of my experiments I need to coat a 3D printed ABS part with a thin layer of silicon rubber:

Basically I want to make sure the molded silicon will adhere to one mold (the negative side in the picture above) but not the other. I'm using V-SURE SILICONE NL Standaard from VOSSCHEMIE BENELUX :

To ensure the positive side will be realised after rubberisation I use the realise agent V-SURE TRENNSPRAY 400 GR from the same company:

I was wondering if there is anything similar for adhesion. Something like a spray glue or something I can smear with a brush. Thanks for your help in advance.

P.S.

1. I have absolutely no idea what are the products I'm using. I just bought them in a local shop for sculpting. I tried translating the website or googling the names with no good results. It would be also a great help if you could help me know what is the official/scientific names of the mentioned products.

2. I'm not able to find the right tags for this post. I would appreciate if the moderators could guide me with that.

3. I have also posted this question on Reddit (molding, modelmakers and ResinCasting)

4. Maybe there are other moldable ruberry materials which have a better adherence to ABS? Any other type of flexible, wear resistance and strong rubber will do. For example I have seen lots of tinkers all over the internet using Caulk mixed with some moist absorbent powder (e.g. cornstarch) and oil, or soaked in water+soap.

5. Surprisingly the silicon sticks firmly to the glass beaker. I can't even remove it with a cutter!

• No such thing, at least not one easily accessible to a customer. Just clean the part properly, it'll stick imo. But a form with parallel walls is not going to work. You'll never get anything out of it.
– Karl
Dec 28 '17 at 11:10
• Thanks for the comment. No such thing, at least not one easily accessible to a customer If there is anything I might be able to order it. If you give me any names? Just clean the part properly, it'll stick imo. Well, I did my best to be sure the surface is clean. but it doesn't. I'm thinking maybe I should change the morphology so there will be more roughness. a form with parallel walls is not going to work. You'll never get anything out of it. I do not understand this. would you please elaborate?
– Foad
Dec 28 '17 at 11:13
• What you have is prepolymerised PDMS with acetyl endgroups. Those hydrolyse with water from the air to form acetic acid and the remaining reactice chain ends connect and crosslink. Unless VOSSCHEMIE has developed sth. revolutionarily new. ;-)
– Karl
Dec 28 '17 at 11:16
• @Karl So in my publication should I name the material as PDMS or silicon?
– Foad
Dec 28 '17 at 11:19
• I have no choice for PLA over ABS. We have this one 3D printer and it works with ABS :(
– Foad
Dec 28 '17 at 12:14