Prototype tree done. Was: Watering down PVA to spray - dilution?

[olicana]

There seems to be a lot of different views on the best PVA dilution for putting in a hand pump spray bottle. I've seen everything from 1:1 to 1:4.

I have several PVAs from the cheap stuff I use for sand and grit basing, which I buy in a 4 litre bottle, to Gorilla glue that I use for making MDF buildings, etc.

I think, if you can tell me the best dilution for the good stuff (Gorilla) I can work it out from there.

I'm planning to replace my current 28mm deciduous tree stock and I want to use it to stick flock to coir, and seal the result. The spray bottle technique looks appropriate to my needs but I have never used one before.

Recommendations please.

[SotF]

There seems to be a lot of different views on the best PVA dilution for putting in a hand pump spray bottle. I've seen everything from 1:1 to 1:4.

I have several PVAs from the cheap stuff I use for sand and grit basing, which I buy in a 4 litre bottle, to Gorilla glue that I use for making MDF buildings, etc.

I think, if you can tell me the best dilution for the good stuff (Gorilla) I can work it out from there.

I'm planning to replace my current 28mm deciduous tree stock and I want to use it to stick flock to coir, and seal the result. The spray bottle technique looks appropriate to my needs but I have never used one before.

Recommendations please.

Gorilla Glue isn't something that works that well with it. The main gorilla glue expands as a foam...

Your best option for diluting PVA is some of the basic options, Elmers All Purpose is one of the better ones and you kind of need to figure the exact ratio yourself because it varies by specific pva/white glue you want to use to getting it to the right fluidity to go through the bottles.

Also, make sure you can either have the time to run a lot of HOT water through the spray portion after using it or have some trash spray bottles for it, because they gunk up pretty quickly if you aren't always using it

[Fitz]

Gorilla Glue isn't something that works that well with it. The main gorilla glue expands as a foam...

Gorilla is just a brand, it's not a specific type of glue. They make all sorts; the one you're thinking of is one of their polyurethane glues.

Regarding thinning PVA for spraying: I've never actually measured the proportions, but I dilute it until it runs like cream.

I've always found spraying PVA quite problematic, so these days I spray the foliage or ground-cover or whatever with isopropyl, and then drip 50/50 thinned PVA/water on to it with a disposable pipette. The isopropyl cuts the surface tension of the water, and each drip spreads out to cover quite a substantial area.

[OSHIROmodels]

I've always found spraying PVA quite problematic, so these days I spray the foliage or ground-cover or whatever with isopropyl, and then drip 50/50 thinned PVA/water on to it with a disposable pipette. The isopropyl cuts the surface tension of the water, and each drip spreads out to cover quite a substantial area.

This is a good method. Gets you more control as well.

[olicana]

Thanks, guys. I'll try the surgical spirit (isopropyl) option. Probably trying both spray and dribble methods in conjunction with the spirit to break surface tension. Very much in the experimental and prototype stage at present - I have my first unflocked tree. Already discovering a lot for 'mass production' later.

Gorilla Glue isn't something that works that well with it. The main gorilla glue expands as a foam...

It's the white PVA Gorilla stuff, not the brown Gorilla stuff that foams when exposed to moisture. I have both.

I have more glue than you can poke a stick at. Checking stocks yesterday, I have over 7 litres of PVA of various sorts and quality (having recently replaced my 4 litre bottle of basing PVA), plus brown Gorilla, several tubes of polystyrene cement, super glue gel and liquid, Araldite epoxy, contact adhesive, wallpaper paste, and I even have a bottle of Gloy gum that I can't ever remember buying. Love my glue!

A few weeks ago someone gave me a full unopened litre bottle of Gorilla PVA glue that had 'gone funny'. It was very thick and looked like lumpy porridge. I cut the top off the bottle and ladled it out into a bowl, added 250 ml of water and blended it with an electric kitchen whisk. Worked a treat. Now in jam jars waiting for me to find a use for it - spraying perhaps?

[olicana]

I didn't spray to stick the foliage in the end. I used a large, very soft, flat brush to apply creamy PVA (with a bit of soap liquid to break surface tension) directly to the coir. Then I used a spray PVA (2 water:1 PVA + a bit of liquid soap) to fix it all and add the final scattering of flock highlight.

I think it came out OK for a prototype. Thoughts can be found on my blog with a couple of other close up photos of the tree - taken during game in progress.

http://olicanalad.blogspot.com/2021/08/trees-first-prototype.html

[BillK]

Result looks great.

[brunei35]

Looks excellent.

Will you be doing a step by step on 'how to' on the blog once production batches you mention start with the short cuts you mention?

I would be interested for one

Cheers
Tony

[olicana]

Thanks, BillK.

Tony,

The short cuts are pretty basic, mostly revolving around prepping the coir. I did pretty much everything out of sequence when putting it on the prototype's branches; it was a very messy pain in the bum;  I  had to trim half of what I did put on to create the layered effect after it had dried; it made painting the trunk after spray undercoating everything dark brown more difficult than it should have been.

I think I've solved all of these problems - including the rather frustrating experience of gluing the coir to the branches. Basically, prior to sticking the finished but unflocked coir onto the tree, the tree and the coir part of the foliage need to be made and undercoated completely separately from each other. I've done some experiments on the side and I think I have the method down pat.

I will do a full explanatory post as soon as the first trees are coming off the finished end of the line. My plan is to do 30 - 36 trees, rolling through at various stages of completion as three or four batches - so I can be doing tree stuff in the 'drying times', there is a lot of drying time.

I'll start making them in a couple of weeks. Next week, I'm making my desert play mat so I'll need the whole table for several days.

[brunei35]

Great news, many thanks and look forward to the post.

Cheers

[Mako]

You can also use cheap, Dollar Store, or equivalent hairspray.  The cheapest you can find, preferably unscented.

It is usually stronger than other more expensive types.

For deciduous trees, less is more.

You can use fine, metal, or plastic mesh, glued in a roughly umbrella pattern, across the top of your "tree", and then, depending upon the type of tree, down the sides too.

Once you've glued that to the major branches, and it has dried, you then take a pair of small, sharp scissors, and cut away much of the solid mesh, in order to make your foliage coverage a bit more realistic - more foliage is closer to the branches of your tree(s), and less or none in between them, if you get what I mean.

Then, instead of using clump foliage, spray the remaining mesh with the hairspray, trying to avoid getting it on the major branches, and use loose, foliage material instead.  Either sprinkle it over the glued sections, or dip them in the foliage flocking.  Sprinking is better, for a looser, and more realistic coverage.

Once all the flocking has been applied (hopefully not to your branches and trunk), spray again with hairspray again, in order to help set it in place more permanently.