do you use double sided tape to hold the sheet in-place?
wait , i just raleized , did you mean durring games , or durring the griding process ?
durring the gridding process , i went to the game store and put 2 table toppers together , each is 4X6 . it formed a surface 6X8 .
lay out the sheet on the table toppers , and iron it to get out most of the wrinkles .
i took 3 yard sticks , and several clamps . i aligned one edge of the sheet and table edge , placed the 3 yard sticks aloing that edge and clamped it down .
using the table cover clips , we then clipped the far edge in place using 8 of the clips .
i and one of my players then took 3 heavy duty card stock squares i had cut to 3&5/8 square and put them along the edge i had clamped down , against the yard sticks : one in the middle , and one about 6 inches from each edge .
i then took a metal straight edge i had that can be connected in pieces between 4 and 16 feet long and connected 2 of the pieces to make it 8 feet long . i placed the straight edge against the 3 card stock squares and used a fine tip sharpie to trace a thin line . checked the like by fliping the straight edge up , if it was darke enough and solid enough , we moved the 3 card stock squares up , and aligned them along the newly traced line . move the metal straight edge up to the edge of the card stock , and trace again , repeat untill its lined off all the way in one direction .
then carefully moved the yard sticks to the side , and clamped them down along one side of the table . then repeated the above process untill the griding was complete .
it is important to use the 3 square method as you go , the entire process . it helps keep the grid lines fairly accurate . granted , its not absolutly perfect , but it wont be notciable when you play if you do this . its also important to have a straigh edge that is atleast as wide/long as the table surfaces . we tried doing this before for some other games , and using shorter straight edges made for some VERY warped lines in some areas , some of the squares looked like diamonds which only looked worse because the squares for that game were only 1.5 inches , so it was obvious .
also we color cordinated our sheets and grid lines . i went to the craft store and bought some individual markers , so our green sheets have a olive drad grid line , our arctic sheet has sort of ice blue grid lines , our tan sheet has brown grid lines , and our grey sheets have black grid lines . this way , they are part of the battle field , but dont detract from the scenic appeal of the game . thats especially important since this is a fan made project , so you are bound to have a few miss happs here and there , so this way they tend to blend in more .
its a bit of a back pain to do , but well worth it .