Envirotex Lite for 28 sq. ft. River

Model Railroader Layouts and layout building
1

I’ve read a few previous threads that touched on this subject, but not for such a large area. My one river is about 29 sq. ft. in size with one end being about 2 1/2’ by 4’ and adjouring section about 1 1/2’ x 3 1/2’ and the other end about 2 x 2’ with about 9’ of 1 foot wide area in between and a small stream off the river of 10"x18". I bought 4 gallons of Envirotex Lite and was hoping to do this in two layers, but not sure if 2 gallons will be enough to cover the first layer.

I read the Envirotex instructions and I think I’m going to have to mix up each gallon separtely to do the first layer and get the 2 gallons poured right away.

Previous threads indicated that tinting with several drops of acrylic paint should be all thats needed, but nothing covering this much epoxy.

The river is made with pink insulation foam board for base and side walls. I painted everything with laytex paint, a special gossy paint, covered with Lite Plaster, wetted powdered grout and finally a watered down acrylic paint for the final coating. It’s primarily black and slightly grayish. I was thinking of tinting epoxy using black acrylic paint. I’m modeling the New River in West Virginia.

I would appreciate anyone’s help with this subject.

Thanks

Gary (Coastie71)

2

Gary, I don’t know if you saw the thread that I started back in 2020, but here is a link to it:

https://cs.trains.com/mrr/f/11/p/281865/3234741.aspx#3234741

It covers some of the issues that concern your pour. I used Envirotex Lite to cover a 12’ x 30" area. The photos no longer show up in that thread, but I can repost them if you are interested.

Rich

3

2 gallons is 0.267 ft3, so for 28 ft2 coverage the thickness (if you use all 2 gallons) will be about 1/10" (precisely 0.114"). Levelness is an issue (is the entire 28 ft2 within 0.10" of level) to get full coverage. Not sure how thick the Envirotex should be in the final application.

Edit: in the above link the poster used 1 gallon for 30 ft2 - which would have resulted in a thickness of about 0.05", apparently plenty for the application. Levelness would still be an issue, but a large pour, while scary, is do-able.

4

Levelness is indeed critical. I went to great lengths to ensure an absolutely level surface across the entire 12’ application. Envirotex Lite is not real thin and watery, but it is not so thick that it will stay in place without running if the surface is not level.

Rich

5

It has been a few years since I did the pour on my layout, so I don’t recall the actual depth of the Envirotex Lite mix. A 0.05" thickness would be 1/20th of an inch. That seems pretty thin. Had the question of thickness been asked of me, I would have estimated 1/8th of an inch. It was certainly thicker than 1/16th of an inch as I can best recall. ( I just went back to read my old thread, and I did state there that the estimated depth was 1/8").

I would offer this comment as to thickness. Over a wide area such as 28 to 30 square feet, the tendency of the mix will be to spread out over a wide area. The Envirotex Lite instructions do warn not to pour more than 1/8” thick at one time. Thick pours should be done in successive pours, allowing each pour time to cure.

Rich

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Rich, I appreciate your quick response. I didn’t see the info in the link you gave me, but I did see another thread where you said you used 5 quarts to cover the area. I thought you were showing inches instead of feet in that thread, but apparently your area is 30 sq. ft. (12’x30"). I don’t think you indicated the thickness that produced. Could you indicate that and clarify the amount used? But if you did use 5 quarts to cover that area, I’m thinking the 2 gallons should cover my 28 sq. ft. The Envirotex Lite site says 1 gallon covers 32 sq. ft. to 1/16" that’s why I thought 2 gallons would produce about a 1/8" thickness and if I do another 2 gallon coat on top I should get around 1/4" total thickness which is what I’m shooting for.

One of the problems I do have is levelness. There is at least a 1/4" difference between one end of the river area and the other. Although the levelness varies somewhat along the approximately 16’ distance between each end.

If anyone thinks I should use 3 or 4 gallons for the first pour because of the not fully level area please let me know.

Again, Rich I really appreciate your information and help.

Thanks, Gary

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PennsyLou, appreciate your detailed information. Unfortunately, my math skills stink and I’m not sure how to interpret ft3 and ft2. I only know sq. ft. so I’m not sure how to interpret your comments, but the levelness part is where I’m really worried about (including Rich’s additional comments), but not sure what I can do about it now. I tried to fix it when i was putting on the Lite plaster coating, but I had alot a problems with that material.

Thanks again for your quick response and help.

Gary

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I’ve done a lot of Envirotex Lite pours, but generally small features. I try to make multiple pours, at least two and maybe three or four, to allow for deeper spots and shallow spots. I never buy more than the quart size. I find I only use a fraction of that, but by keeping the bottle caps and rims scrupulously clean, the shelf life easily runs to years. I pretty much only do very small pours.

I realize the bottom of a water feature is visible, so I spend some extra time making sure it’s “presentable” for a clean, natural, feature, or perhaps a bit cluttered for water in a more populated area. Small rocks, sand and sticks glued in before pouring work well, and dark, even black bottom features will add a nice illusion of depth and break up the uniformity of a large water feature like yours.

I also like to tint my pours with cheap acrylic craft paint. I typically start with a darker green for the bottom pour, and progressively lighter greens. My top layer is typically clear. The result is a pond or stream which I can see the bottom of, but the Envirotex gets more opaque and darker as it goes down, more like a real body of water. In the top layer, sometimes I swirl in a bit of light green, which looks like floating vegetation. I do this after the last pour, applied with a pin so the light green is very thinly applied.

As suggested, don’t do thick pours. This may result in trapped air bubbles as the resin hardens.

Once I mixed the bottom layer incorrectly, and after several days it remained sticky. I decided to put a second layer on rather than remove the first, and that set perfectly.

Yes, changing base surface levels can be a problem. I deliberately built a swampy area with small variations in height. I put sticks in at the boundaries, held in place with white glue to dam the higher levels.

Finally, pizza is your friend. Save your pizza boxes

9

Gary, I bought 1 gallon plus 1 quart and 8 plastic mixing bowls. I used just over a gallon with the rest of the unneeded. The pour was 1/8" deep.

The one gallon came in two 1/2 gallon jugs, an epoxy and a hardener. The quart came in two 16 ounce jugs, an epoxy and a hardener. I made a quart of mix to begin the pour, and then each successive pour was another quart until I had filled the river bed. As long as the successive pours are done relatively quickly, each successive pour will blend in with the prior pour, so you need not worry about lines or ripples since the mix is self-leveling.

You won’t need a 1/4" depth of mix unless your river bed is 1/4&q

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Here are some photos of my river bed and my pour.

These first three photos show the painted river bed from three angles before the pour.

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These three photos show the river bed from three different angles after the pour.

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While no where near as large as yours, I realized it doesn’t much matter should a layer not come out correctly b/c it gets covered.

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Except the last one. [swg]

Rich

14

Depending on how your layout was built, you can temporaraly unlevel your layout with shims on the feet for the pour to level the river, after curing remove the shims.

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Mister Beasley, I appreciate your comments and the info concerning tinting for each pour, etc. I also want to avoid the deep pour, just concerned that too much of the epoxy will fill the lower end and not enough the other end on the first pour.

Again, thanks for your help.

Gary

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Rich, thanks for the clarification and additional info. So, if you covered the 30 sq. ft. with 5 quarts I think I’m going to be OK with the 2 gallon pour for the first layer then. I bought 4 gallons total so I think I can cover it in two pours and get enough to cover at least 1/8 on the higher end.

I think I’m going to try to level with the shims under the legs since I didn’t want to mess with the river bottom which was made with 1" foam on top of my 3/4" plywood. I coated the foam with gossy paint, light plaster and grout and then painted it again with acrylic paint as I wanted to make sure the epoxy wouldn’t melt my foam. The banks along the river vary in height of about 2" to 5" and are also made with pink foam, painted with the gossy paint and laytex paint.

Again, I really appreciate your detailed help and your river images are really nice.

Thanks, Gary

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RRebell, I think I’m going to go with your method to try to level the river. The only thing is my levelness varies so much along the entire length. For instance about 6 feet of the higher end appears level, using a 4 foot level, but then the rest can look level in some areas, but slight 1/8" or so variations in other areas.

I built the benchwork with 2x4’s because the entire layout is not supported by any walls. Its really solid and heavy, but if I can get the shims under some of the legs, I think that will avoid some of the levelness issues.

Again, I want to thank you for your input and help.

Gary

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Thanks, Gary, and good luck with the pour. Keep us posted and give us some photos.

Rich

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Leveling can be a compromise even in 1-1 housing. Just go with what you think is best.

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Rich, I let everyone know how it went with the pour. As far as photos, I have no idea how to post photos from my phone on the forum. Tried to figure it out quite a while ago, but never could.

Maybe someone could send me instructions on how to this. I use my desktop computer to access Model Railroader.

Thanks, Gary