My Br55 So Far

[rube]

Any change you want the tell us what kind of material the mother mold is made from?

Mini review.

The mother mold is Plasti Paste. I love it and I hate it. It cures fast and is easier than fiberglass in general but it is hard to smooth out and maintain a constant thickness. The little fiberglass bits want to stick to each other and pull more material with them than you want as you trowel it around. Takes practice I guess.

Plasti Paste comes as two parts. You get a bucket of chopped fiberglass mixed with one part of the usual two part urethane system and a couple of quarts of brown liquid other part. You have to mix the two parts very thoroughly and that takes a few minutes since the fiberglass part wants to form little clumps that resist mixing with the liquid. Smooth-On says it is best to pour it out immediately and spread it out roughly rather than try to apply it bit by bit from the container. I forgot that part until the hand holding the container started to get hot.

After the mold after it cured I noticed that the upper part an application was less dense than the lower. It seems that the urethane has a tendency to drain away from the fiberglass and migrate down. I probably just needed to put it on in thinner layers.

I am also not fond of the little hairs that inevitably stick out of the main mass after it cures. I sanded most of them off and brushed on a coat of smoothcast so I could handle it without gloves. Scritch, scritch, scitch...

 

[DogWizard]

Here's a little trick for smoothing the PlastiPaste - use rubbing alcohol. When everything is roughly shaped and just as it begins to set, pour a little bit of alcohol on the piece and smooth the PP out. I recommend using a rubber glove (or two) as it gets HOT but the end result is very smooth - almost like cured resin. It evaporates quickly so you will need to reapply in multiple small pours but it really does the trick. You can also do some light shaping, certainly better than using a trowel or mixing stick. My Hammer moulds are nice and smooth - well three of the four. :rolleyes I didn't discover the trick until one side of the blade mould was already done...

Hope this helps - good luck!

 

[rube]

The alcohol smoothing didn't work so well for me. Lack of skill probably since I saw that your molds were quite a bit smoother than mine.

 

[rube]

Progress...



Lower receiver casting in 320. Doesn't melt when you look at it too hard.

Partially Painted

I picked this up to help with the air bubbles. I'll pressure cast the scope and the heat shield.

Guess what this is going to be?

 

[DreadMullet]

oh my god... that is freaking sick rube, Great job.



cant wait to see one with a nice paintjob

 

[LastSpartan]

Holy...



I want one so badly now.

 

[S1l3nt V1p3r]

The raw pull looks like wood! :eek



Great job Rube! I guess the contraption you've made is for making rotocasting easier? I bet all that Plasti paste gets heavy when the mold is huge, right?

 

[SavvyTank]

I havet checked up on this in a wile and now look. your perfecting it. i cant tell if im salivating from this taco or your combined work. I hope to be able to see in RL how it all turns out one day.



Keep up the awesome work.



Savvy

 

[vulture]

I dont even believe you now when you say you made this, this is obviously STOLEN directly from Master Chief himself! Haha great work guys

 

[Sean Bradley]

Brilliant work!



Love the rotocasting frame.. nice design.



I'm interested to see the results with the pressure pot too. Was it expensive?

 

[LeeKegan]

Rube, That roto molder looks awesome along with the parts.

 

[rube]

I'm interested to see the results with the pressure pot too. Was it expensive?

The results of using the pressure pot were mixed. The good, all bubbles were eliminated from the casting. The bad, the mold was made with rubber that was not vacuum degassed so every bubble in the rubber was compressed making the parts surface *very* bumpy. It appeared for a time that the mold was ruined but it seems to be slowly recovering it original shape.



My rotocaster cut the time required to make a cast by a lot even though I have to spin it by hand. Two 6 ounce batches are sufficient for the upper receiver.

 

[mightymints]

Hmm, Hows that mold recovering?

 

[rube]

Hmm, Hows that mold recovering?

It's fine. just a few lumps to sand off the casting.

 

[Bloodl3tt3r]

This thread has gone beyond Elite, it is now a rotocasted BR made from awesomesauce mixed with demigodliness (in small plastic cups).



Well done to both of you.

 

[Spartan648]

Any change you want the tell us what kind of material the mother mold is made from?

Mini review.



The mother mold is Plasti Paste. I love it and I hate it. It cures fast and is easier than fiberglass in general but it is hard to smooth out and maintain a constant thickness. The little fiberglass bits want to stick to each other and pull more material with them than you want as you trowel it around. Takes practice I guess.



Plasti Paste comes as two parts. You get a bucket of chopped fiberglass mixed with one part of the usual two part urethane system and a couple of quarts of brown liquid other part. You have to mix the two parts very thoroughly and that takes a few minutes since the fiberglass part wants to form little clumps that resist mixing with the liquid. Smooth-On says it is best to pour it out immediately and spread it out roughly rather than try to apply it bit by bit from the container. I forgot that part until the hand holding the container started to get hot.



After the mold after it cured I noticed that the upper part an application was less dense than the lower. It seems that the urethane has a tendency to drain away from the fiberglass and migrate down. I probably just needed to put it on in thinner layers.



I am also not fond of the little hairs that inevitably stick out of the main mass after it cures. I sanded most of them off and brushed on a coat of smoothcast so I could handle it without gloves. Scritch, scritch, scitch...

There is a trick you can use with the plasti paste to get a even coat all over, Add a colorant to every other coat, use one or two different colors. Start with the natural color of the paste, then add a dark color to the paste for the second coat, natural color for the third coat and so on

I believe there is cotton flock in plasti paste not fiber glass, Suggested to me by a smooth on tech, to get a smooth plasti paste surface brush on a layer or two of resin on top of the curing plasti paste that will smooth out all of the sharp points.



I also want to say fantastic job guys, for going the extra 150 yards and adding so many extra fine detail's and touches.







Spartan 648

 

[rube]

I believe there is cotton flock in plasti paste not fiber glass,

It is glass fiber in Platipaste 2. Never used 1 so I don't know.

 

[Yuki Kedamono]

you work that wood! lol

i'm sure nobody's said it yet i just had to get it out in the open an off my chest, lol.



on a more serious note i can't get over how utterly awesome this is. I wish i had your insane talent.

I especially loved how you added the video feed for the scope in your other recent work. i believe it was the sniper rifle was it?

 

[haji]

sorry if this question was already answered, but looking through 22 pages isnt easy



Is the magzine going to be removable in the casted version? along with the bolt function

 

[LeeKegan]

sorry if this question was already answered, but looking through 22 pages isnt easy



Is the magzine going to be removable in the casted version? along with the bolt function

Not at this time.