Casting Blade Runner PKD Grips?

I'm looking at making copies of the grips on my water blaster so I can replace the blue ones I currently have with amber.

What I don't have is much experience in clear casting/tinting.

I have a degassing and a pressure pot set up, but I'm looking for tips on the best type of resin/pigment to use, what the actual process is (do I need to degass and cast under pressure,how much tint to use, do I need to layer, what type of curing time should I expect etc)

Any assistance would be much appreciated, I'm trying to get as much useful info as possible to reduce wasteful experimentation to a minimum

Anyone done clear casting at all? :confused

Throw me a bone!

Hi there,
Seems like you have tons of equipments available! It should be a breeze!

-You can create your mold from any silicone (I use smooth-on Mold Start).

2 options from the get go:
- If you want filled (heavy) resin parts, use a normal simple mold / 1 part with a box (I make mine from 1/4" foam boards) : see https://www.youtube.com/watch?v=LSH19G_6Yeo
- If you want to replicate an empty shell part, you'll need to go more complex with a 2 parts mold. It's just a little more work but will get you a perfect replica of the grip. That implies you knowing how to do it (check youtube for 2 parts molding) and make sure to put a pour hole where it will be easy to clean and vent holes to prevent the bubbles from being trapped.

I suggest option 1, it will give a heft to the gun + it's easier, you can try option 2 later. Instructions are for option 1.

-Glue your part securely to the bottom of your mold. To prevent leakage, I use double sided tape on the bottom, then stick my part on it, and baby powder to remove the stickyness. Works like a charm!! Thanks to DaveG for the tip on this as it prevents tons of problems. See https://www.therpf.com/showthread.php?t=264222

-Measure your silicone needed (https://www.smooth-on.com/support/calculators/) , degass if needed (if you have the equipment, I would definitely do it), pour and then you can optionally put your filled mold in the pressure pot. BEWARE if your part is hollow, make sure to fill it properly with non-sulphure clay to prevent the pressure pot to pull it in!!!

-Wait for the cure time (make sure to check your silicone technicals.

- Remove silicone from mold, admire your handywork.

NOW, you have a mold! It's important to note that since you want clear resin, and have a pressure pot, I assume you'll use it to crush those bubbles. If you do that, and your mold wasn't properly vaccuum degassed (chamber) and/or bubble free from the pressure pot, those bubbles will get filled in the pressure pot and you won't have perfect casting. But again, with your hardware, no reason to have any problems.

At this pt, you need to get clear resin and to have bubble free castings. Smooth on has a few (smooth cast translucent or crystal clear) but there's just tons of brands.

- Measure your fill space with rice or any other medium to give you the qty of resin to use, then mix and pour.
- Put in pressure pot for as long as the cure time of the resin technicals.

Tinting is all about trial and error. do some test by noting the number of drops to use and adjust accordingly!

I personnaly use https://www.smooth-on.com/products/so-strong/:
https://www.youtube.com/watch?time_continue=21&v=IRfKAKT-18Y

Thanks for the response! I've got the moulding side covered, it's the clear casting I'm looking for tips on.

- Do I need to use polyeurethane clear or will polyester do?
- Do I need to both degass the resin and pressure cast?
- Do I need to layer, or is one pour okay?- What kind of setting time for a tack-less cast?

Those kind of things

I always use polyeurethane resin, so not sure about the polyester one .. sorry about that one.

I very rarely degassed my resin since I have a pressure pot and my pot life is quite short. Last thing I want if the resin to start turning before I poured it. The pressure pot should crush the bubbles anyway.

I never use multi layer unless it's for slush casting. I would be afraid of layer lines in the cast.

Are you planning solid or shell cast?

Solid, fortunately

Good stuff, I think that those water pistol needs some heft too! I have 0 BR guns since I always thought this whole 1K over gun was just madness, at some pt, I'll get a resin cast and build it too!

The 2049 K pistol is growing on me, and I haven't even seen the movie!! :facepalm

Hopefully, this all helped a little!

So, while it looks like you've got almost all the expensive parts of the process covered, I know there are folks that already make resin grips specifically for the water gun. they show up in the junkyard here, and I think in the project runs. It may be worth at least seeing what a set of those runs, and compare it to what any new materials are going to cost you. it may be worth buying a set instead of making; unless the primary goal is to make something cool with your own hands, as opposed to just ending up with a set of grips.

While I don't have a huge amount of clear casting experience, I've had great success getting completely bubble free casts on a few projects using only a vacuum chamber with this clear:

https://www.amazon.com/gp/product/B00D6T6XU8/

It has a fairly long pot life (plenty of time to de-gas the mixture before and after pouring), and it sets up hard and completely non-tacky after a day - it can be demolded after 5-6 hours but the castings will still be flexible and need some additional heat or sun exposure to fully set if you're in a hurry and need them in less than 24 hrs.

When setting up your mold you'll want to incorporate a large reservoir above the mold gates. This reservoir will catch the resin as it foams out of the mold under vacuum, and allow it to re-enter the mold as the bubbles break/when the vacuum is removed. When the resin stops foaming, slowly let the air back into the chamber - the atmospheric pressure will act much like a pressure chamber and crush any lingering bubbles.

As mentioned above don't forget to de-gas your rubber before pouring the mold!

If you use the above resin and procedure you won't need your pressure pot for something as simple as the BR grips, but it certainly wouldn't hurt to use it too if you want to be thorough.

I've also reproduced the BR water gun grips in clear, but had to use the so-so alumilite clear that Hobby Lobby carries as I ran out of the good stuff. It's not worth it - go with the better version in the link above.

Here's a link to a photo of my mold. Note I was low on rubber and wasn't making more than a couple sets, so I didn't incorporate the overflow reservoir into the design as would have been preferable for ease of use (added later by forming one from clay). The acrylic side of the mold provided a flat back for the grips.
https://www.flickr.com/photos/50105970@N06/37318872191/in/dateposted/

Edit: Oops, just noticed you are in UK. I'm not sure if the Alumilite would be available there, so not sure what to recomment :\

Strikerkc said:

So, while it looks like you've got almost all the expensive parts of the process covered, I know there are folks that already make resin grips specifically for the water gun. they show up in the junkyard here, and I think in the project runs. It may be worth at least seeing what a set of those runs, and compare it to what any new materials are going to cost you. it may be worth buying a set instead of making; unless the primary goal is to make something cool with your own hands, as opposed to just ending up with a set of grips.

Click to expand...

Yeah, I took that into consideration, but wanted to learn how to do it for some other stuff I'm planning

- - - Updated - - -

Thanks, that's all good info. I've bought some cheap polester resin and just going to play around with it and see what happens

E Williams said:

While I don't have a huge amount of clear casting experience, I've had great success getting completely bubble free casts on a few projects using only a vacuum chamber with this clear:

https://www.amazon.com/gp/product/B00D6T6XU8/

It has a fairly long pot life (plenty of time to de-gas the mixture before and after pouring), and it sets up hard and completely non-tacky after a day - it can be demolded after 5-6 hours but the castings will still be flexible and need some additional heat or sun exposure to fully set if you're in a hurry and need them in less than 24 hrs.

When setting up your mold you'll want to incorporate a large reservoir above the mold gates. This reservoir will catch the resin as it foams out of the mold under vacuum, and allow it to re-enter the mold as the bubbles break/when the vacuum is removed. When the resin stops foaming, slowly let the air back into the chamber - the atmospheric pressure will act much like a pressure chamber and crush any lingering bubbles.

As mentioned above don't forget to de-gas your rubber before pouring the mold!

If you use the above resin and procedure you won't need your pressure pot for something as simple as the BR grips, but it certainly wouldn't hurt to use it too if you want to be thorough.

I've also reproduced the BR water gun grips in clear, but had to use the so-so alumilite clear that Hobby Lobby carries as I ran out of the good stuff. It's not worth it - go with the better version in the link above.

Here's a link to a photo of my mold. Note I was low on rubber and wasn't making more than a couple sets, so I didn't incorporate the overflow reservoir into the design as would have been preferable for ease of use (added later by forming one from clay). The acrylic side of the mold provided a flat back for the grips.
https://www.flickr.com/photos/50105970@N06/37318872191/in/dateposted/

Edit: Oops, just noticed you are in UK. I'm not sure if the Alumilite would be available there, so not sure what to recomment :\

Click to expand...