Quick terrain board question

[snitcythedog]

So if that works out, I'm thinking I should get away with thin boards.

A couple of things that can mitigate warping if you are looking at doing thin boards.  Building a frame of battens under the boards will help.  How they are stored will also help.  If you can do the board in multiple thin sections that can be stored flat under furniture such as a couch, bed or dresser then you will lessen the chance of the board warping by leaning in storage.  Building the board in smaller sections will lessen the chances of warping.  You can also prime the baseboard prior to using any paint or glue.  Simply buy two cans of auto body primer and apply them in several thin coats covering the whole board top, sides and bottom.  This should seal the MDF or plywood and can limit the amount of moisture that gets into the wood.  Your best bet would be to search the internets for terrain boards and see what others have done even if their design is not wholly similar to yours.  You also will have the added benefit of reading or hearing first hand about what went wrong with their boards and what they would do different.  Finding out about others mistakes or pitfalls prior to your first attempt will definite help.  

Do you know which is most prone to warping, MDF or plywood?

All wood products can warp so it is not a matter of which is more prone to doing it.  Pre-treating with a primer, supporting with a frame, how the board is stored or building in smaller sections will all mitigate warping.
Hope that helps.
Snitchy sends.

[fastolfrus]

If you have supportive battens around the underside edge they could also help to stop the boards moving from the supporting table.
Also you can get a sort of rubber sheeting that is designed to stop rugs or tablecloths from slipping. Sort of thin dimply looking stuff, they sell it in carpet shops, IKEA, sometimes even in Poundland (but they only get small bits). If you could fix that to the underside of your board it wouldn't slide about. Also, wouldn't scratch the dining table (if that was the support)

[Khadrin Stonetooth]

Fram Framson said : Hm, never thought about putting the battens on TOP of the board before. There's an idea. Also makes it easier to pre-make irregular edges (hills, etc.) which will line up in multiple configurations.

You're absolutely right Fram, I've seen on the net several examples of people who make templates with battens so their hills, slopes and even rivers will perfectly match from a tile to another. I would also add that sanding the battens make the edges straight so the seams between tiles are less visble.

[Charlie_]

Hm I've got a lot to consider still.

I've done a rough design of what boards I'm going to need. It'll be four 2x4 boards and 6 2x2 boards, with a mix of river, road and open field. Obviously I won't be needing to make them all straight away. At a later date I'll do some with hills, but that will be way off in the future. To start off I want roads and a river (plus a little ditch / stream that runs off one of the river boards), with one section where they cross at a ford.

I know that just using 2x2 boards will make warping less of an issue, but I'm going to have some 2x4 boards for two reasons.
1) It will mean less gridlines on the battlefield. I will be trying my hardest to make the joins seamless, but know I can only do it so well. I want to have as few seams visible as possible when they are not needed. Hence I can put together a battlefield with three 2x4 boards rather than a grid of 6 2x2 boards.
2) It will mean I won't be so tied to the rivers and roads bending at right angles. In particular I will have one long 2x4 river section that will have a gentle, natural curve, and one 2x4 road section with a nice meander to it.

Warping and boards joins will be my biggest obstacle though, and a nightmare if it goes wrong.

I'm still debating over MDF thickness. I could well make some battens to strengthen it all. That should mean I could use a thinner MDF layer..... 15mm foam, 6mm MDF and battens to keep it all together. Right?

I might change my mind and go for a thicker foam layer, but I think 15mm is all I need. It means my river won't have big steep banks, but that's fine. I'm also weighing up price and storage issues. If I go for a thicker foam layer I will be getting far less tiles for the same price and it could almost double the storage space I'll need.

Battens will mean they need a little more storage space though....

Has anyone ever considered a 'frame' or sorts to keep all the boards tight together? It will also mean I won't need one big tabletop to put them on, which is a huge issue. I'm really thinking I might do this.  I don't have a big table or masses of roomspace, I'm going to be using 2 or 3 sturdy folding tables, but can't really rely on them for the boards to rest perfectly level on. They will need another tabletop of sorts on top, and that will need to disassemble for easy storage. What I'm thinking is a series of 4 foot 'planks' bolted to two long 8 foot side pieces, all to be unbolted and stored under the bed or whatever. That can rest on the folding tables, and if done right should let the terrain boards sit inside perfectly. What do you think?

As to hiding the joins.... Obviously stopping warpage, a level surface and clean edges will be the three things to make sure I get it right. Does anyone have any words of wisdom on the matter? I've been looking at all sorts of amazing terrain board builds, here, on youtube, on blogs... And even the best looking of them still have very visible joins, which is kind of disheartening.

However... Anyone who looks at the Perry bros' facebook page will know they regular post pics of games they play on their fantastic boards. They obviously have a huge collection, covering many years, I think I remember seeing some of these same boards in the pages of White Dwarf back in the 90s. They don't seem to have any problem with visible joins.... Look at this picture. The slightly different colours of all the boards give it the 'patchwork' look, the actual joins are rather seamless.... Do you think they cover them up with flock, or is it just because they are built properly?



If anyone thinks they've done a good job of hiding joins on their boards, and have some pics, I'd love to see them!!!!

[Khadrin Stonetooth]

Hi Charlie
I don't see how adding battens means that you will need more storage space. If your batten is on top of your tile and have the same thickness than your foam, you need just the same storage space.
Then the board you show has excellent seams between tiles and I am also curious of how they manganed that. Did they just sand the edges ?

[Charlie_]

Hi Charlie
I don't see how adding battens means that you will need more storage space. If your batten is on top of your tile and have the same thickness than your foam, you need just the same storage space.
Then the board you show has excellent seams between tiles and I am also curious of how they manganed that. Did they just sans the edges ?

Oh, I meant battens underneath.

[Peithetairos]

As I am facing similar problems with my board, I thought of using a so called sanding sealer on the MDF/plywood. This should effectively prevent any humidity to effect the mdf. MDF remains pretty straight even when the humidity changes significantly. I think the problem is the use of (too much) water based glues on unsealed MDF.

[Charlie_]

As I am facing similar problems with my board, I thought of using a so called sanding sealer on the MDF/plywood. This should effectively prevent any humidity to effect the mdf. MDF remains pretty straight even when the humidity changes significantly. I think the problem is the use of (too much) water based glues on unsealed MDF.

Yes, sealing the MDF seems like the it's the key.

When you say you are facing similar problems, do you mean you have actually encountered the warping yourself already, or are still in the planning stage like me?

Yesterday I found an interesting video log on youtube of somone making some boards. He used just MDF with foam on top, quite thin MDF, no batons or anything, just good craftsmanship. And he got zero warping.

How do 'no more nails' and things like this compare to regular PVA? Just for fixing the foam sheet to the MDF, so I'm thinking about water content etc.
http://www.diy.com/departments/unibond-no-more-nails-original-grab-adhesive-300ml/70390_BQ.prd

[Peithetairos]

I am still in the planning stage/ test cut stage. I had warping with MDF bases before, but I did not seal them and used too much PVA. No more nails is more like a thick paste and is not readily absorbed into the MDF. I think some glue dots using Liquid Nails should be enough to keep stuff in place. I covered the entire base once and while it was a very good bond, I think that was unnecessary. The less glue, the less mechanical stress I would say.

[Charlie_]

I am still in the planning stage/ test cut stage. I had warping with MDF bases before, but I did not seal them and used too much PVA. No more nails is more like a thick paste and is not readily absorbed into the MDF. I think some glue dots using Liquid Nails should be enough to keep stuff in place. I covered the entire base once and while it was a very good bond, I think that was unnecessary. The less glue, the less mechanical stress I would say.

Mmm interesting. I think I could use thin MDF (6mm?), using no more nails (in dots rather than all over), plus some small nails through the MDF to act as pins.... That should give a good bond with barely any water content to cause warping.....
Im still debating whether to use battens or not. I was against the idea of using them 'on top' of the boards, to form a frame for the styrofoam to go inside, but now I'm thinking that sounds quite appealing. The styrofoam won't need to be cut to an exact size, as I can leave a few milimetres and fill it with filler. It will then rely on my carpentry skills to get the battens all perfectly straight and square!


As to the actual table that the boards will rest on, I have given it some more thought and decided that a simple frame which can be disassembled for storage will be the way to go. But what will it sit on? I was looking at various folding tables of uncertain sturdiness from from Ikea, and then found some good strong looking trestles and was considering having the frame bolted to them, by which point I would effectively be building an entire 8x4 TABLE.....
Then I realised I've got these two good drop-leaf tables. I had discounted them for just putting boards on as they would be crying out to be knocked and flipped over the edges... But the 8x4 frame with a lip to hold the boards will fit perfectly on both drop-leaf tables put side by side. So that's what I'll do! Until I next change my mind.

[6mmfan]

I went with thin mdf board(6mm) and I used "No more nails" to glue the foam on top. Less likely to warp due to the lower moisture content in "No more nails" than PVA. But you may still want to seal the wood as it may warp depending were you store the boards and how dry it is there.

Personally I would go with plywood next time as it is usually less prone to warping and a lot lighter than mdf. I made 16 600mm square boards and they weighed a f*&king ton. Also I would go with battens on top next time as the mean you can have straight square edges and protect the edges and corners from damage.

For the battens if you use them on top, then clamp the pieces together that you want to shape (for rivers, hills etc) so they be shaped to match up the same.