Built Review
Rubble Molds Review II

by: Scott Lodder [ SLODDER ]

Review background

The Kancali rubble molds have been reviewed once already by PLMP110. I won’t repeat everything in that review – I will state that the molds are nicely done and an all-inclusive product. The rest of the review will focus on my impressions using the mold and comparing different mediums – Woodland Scenics Hydocal plaster and Two-part resin.

Plaster Pour One

My first impression of the molds was favorable. The latex used is a very sturdy supple material.
I mixed some WS Hydrocal based on the instructions. This creates a fairly thin mix. I mixed enough to pour over all three molds. As I poured I noticed that there was a considerable amount of surface tension. These caused the plaster to ‘bead’ up and sit in bubbles. This is very similar to what happens after you wash and wax a car then pour water on it. This did make it more challenging to get the plaster in the rubble openings. I used toothpick and coffee stir stick to help work the plaster down into the mold. This worked adequately but eat up a lot of the plaster ‘work time’ which didn’t leave me much room before I had to let it sit and dry.
After the plaster dried I gently bent the latex mold back and eased the pieces out of the mold. The brick pieces were decent, a few bubbles and a few miss pours where the plaster didn’t get down in the mold. The larger pieces came out fine because of their larger surface area allowing more plaster to settle into the mold. The pipe sections were “OK”, they were very delicate and the connector pieces were prone to cracking and breaking on the extraction.
The molds looked great after the first used, they were very easy to clean with an easy brushing with a medium brush.
Plaster Pour One- results

The first pour was an experiment and it showed me that a thicker plaster material should work better. Thicker substances are easier to work into the mold. The first pour also showed me that I might need to wash the molds before the next use. I did like what I saw and I saw potential.

Plaster Pour Two

I evaluated how pour one went and came up with the following ideas

  • 1. Wash the Molds

  • 2. I need thicker material

I took the three molds to the kitchen and used some gentle dish soap on the molds. I let them dry completely.
I set out for pour two. I used the same Hydrocal as in pour one. I simply mixed using less water, making the plaster thicker. The idea behind thicker material was to allow me to push the thick mix into the nooks and crannies with a coffee stick. The thickness would allow the material to overcome the surface tension and make it easier to get rid of bubbles and keep them out. The texture of this mix was almost of pudding, it poured fine and was much easier to push and spread.
Once this dried I gently bent the mold and popped out the pieces. I was pleased with this pour. The pieces came out more uniform with fewer bubble problems and nicer overall look and feel. The pipes were better this time, coming out shaped better but still broken.

Resin Pour Three

I am a fan of pouring resin for detail parts and thought I could do better with the rubble out of resin. My biggest draw was the pipes, I knew resin would help with the breakage problem and would definitely fill the gaps.
I used two part resin that you can buy from MicroMark and mixed it to the specifications. Two equal parts, I used about ˝ of a Dixie cup (bathroom cup/sample cup). I poured this on and spread out over the molds. On this pour I was not thinking ahead and did not clean off the top of the mold very well. When the resin blossomed it expanded and left a large ‘sheet’ of resin connecting all the parts.
When the resin cured it was very easy to remove the parts. Because of the extra blossom it was almost one large piece.
Upon inspection I was pleased. The pieces were nicely molded. There were very few bubble gaps. The pipes came out as expected – just fine. The one big problem was the clean up! The blossom sheet was big and forced me to a lot of tedious cleanup. That lead me to another pout.
Resin Pour Four

I was pleased with the resin parts, just not the clean up. I decided to do the same technique as pour three. On this pour I would pay closer attention to removing as much of the surface over-pour as possible.
I mixed the resin and poured it in small areas at a time. I poured the resin down a coffee stick into each individual mold opening, thus filling each as much as possible. I didn’t tip the cup back to stop the flow from brick to brick. This would have taken too long and left me with no work time. As I went I used a coffee stick to scrape away as much excess as possible. I tried to leave the resin as level as possible and remove as much from between the parts as I could.
Again after the resin cured I was happy with the results. Not much clean up and nicely molded pieces. Very good pour.
Plaster Pour Five

I evaluated how other modelers would use this product and realized that not all modelers have access to or the finances for resin. Plaster is an easy accessible product. I was not as happy with the plaster pours as I was with the resin pours. I had success with a thicker plaster and decided to go one more step – thicker. I mixed the plaster to the consistency of household spackle, almost to tooth paste consistency. This stuff would not pour, I had to scrape it out and apply it manually into each mold hole.
This took a bit more time and effort to accomplish. All the parts came out better that the previous plaster pours, with the exception of the pipes.
Purchased Product

Kancali sells pre made rubble made out of Hydrostone. This stuff is nice, it falls between my Hydrocal Plaster and my resin pours. Nice detail, good mold quality, some bubble gaps. The nice thing with this is the firmness and solid feel of this material.
Final Impression

If you want easy rubble and lots of it these molds are for you. I poured five batches and was impressed with the latex that Kancali used. It is soft, supple and durable. I have used MicroMarks blue two part RTV mold material and I like Kancali’s better. I poured two types of material, I bent twisted, washed, pried, and used a dremel on the blank backside of the rubble and the molds handled all of it.
Your options are 1. scratch build your own mold and rubble, 2purchase pre made rubble.
Making your own will mean you have to make the initial batch to mold. Then you have to purchase the RTV mold material. What do you do with all the extra RTV material? What do make the original out of?
Purchasing pre-made rubble is not cost effective if you need lots of it. At anywhere between $8 and $15 per baggie of rubble means that you will run up a bill pretty quickly. All you would have to do is pour each mold twice and you break even. Everything after that is gravy.

I have taken a second look at the new rubble molds from Kancali. Kancali has come up with another solid product coming from Latex. This review is an in depth review of different materials used in the mold.
Percentage Rating
  Scale: 1:35
  Mfg. ID: Rubble Mold
  Suggested Retail: $16.99 eac
  PUBLISHED: May 26, 2005
  NATIONALITY: United States

About Scott Lodder (slodder)

I modeled when I was a teenager. College, family and work stopped me for a while. Then I picked it back up after about 12 years off. My main focus is dioramas. I like the complete artistic method of story telling. Dioramas involve so many aspects of modeling and I enjoy getting involved in the ...

Copyright ©2021 text by Scott Lodder [ SLODDER ]. All rights reserved.


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