ESD Mat ripples

[eaj0010]

Greetings (I hope this is the right forum for this question),

Long time video watcher, short time poster. I am in the process of building a new ESD work bench this is the first time I've procured a mat that wasn't already pre-assembled with its own clinch stud. This is a rubber mat (2 layer diss/cond type). When I got my new roll and cut the mat to fit my new bench, I noticed a whole bunch of ripples in the mat. Is there any good way to take these out so it lays flat on my bench (heat perhaps)? Thanks in advance.

[mrflibble]

Link no workey. Today's free image fix service:

[wraper]

I attach it to the table with double sided adhesive tape at the sides, few strips of tape in the middle too. In the past I learned that if the mat is not attached to the table, it eventually will ripple heavily on the place where you are working the most of time and finally will start do disintegrate starting from the edge. If fixed it is becomes almost everlasting.

[eaj0010]

Link no workey. Today's free image fix service:

Thank you for the fix!

I attach it to the table with double sided adhesive tape at the sides, few strips of tape in the middle too. In the past I learned that if the mat is not attached to the table, it eventually will ripple heavily on the place where you are working the most of time and finally will start do disintegrate starting from the edge. If fixed it is becomes almost everlasting.

What kind of tape did you use?

[Balaur]

I attach it to the table with double sided adhesive tape at the sides, few strips of tape in the middle too.

I do that too on rubber mats.

Just a word of caution for everybody else: don't use tape with non-rubber, vinyl ESD mats. The plasticizer will make a sticky mess of the tape adhesives.

[rdl]

I use spray paint to stick the mat down. I position the mat, then lift one edge and spray a very light coat of Krylon 1301 Crystal Clear in the areas where the ripples are. Let it dry for just a few seconds, then while it's still sticky drop the mat down and weight it in place with some books overnight.

My work table is one of those "banquet style" tables with folding legs and I long ago peeled off the fake wood grain vinyl that was on the top. It's not fine furniture, so I don't mind doing this to it. If the mat comes loose (it usually does eventually because I don't apply much spray at all) I just repeat the procedure.

I thought about using some kind of spray adhesive at first, but I figured I'd just end up with a gummy mess in the end. The clear acrylic stuff dries hard and you almost can't tell it's there if the mat comes loose and you have to pull it up and re-apply.

[Ericho]

If Its the same stuff I got at farnell (10 years ago) it will sort inself out, just takes a few weeks. 

[nanofrog]

If Its the same stuff I got at farnell (10 years ago) it will sort inself out, just takes a few weeks. 

This is what I'm accustomed to, even with far more recent vintage.

I wonder if it's to do with the actual type of rubber being used for each layer (i.e. SBR or nitrile bottom layer w/ a nitrile top layer). Thinking in terms of elasticity, which would explain why some mats (nitrile/nitrile) will lay flat once the stress of being on a roll is allowed to right itself (type of behavior we've observed). SBR isn't as elastic as nitrile however, so that could store stress during manufacture that prevents it from laying completely flat without mechanical help.

Or maybe we just got lucky.   

[eaj0010]

If Its the same stuff I got at farnell (10 years ago) it will sort inself out, just takes a few weeks. 

This is what I'm accustomed to, even with far more recent vintage.

I wonder if it's to do with the actual type of rubber being used for each layer (i.e. SBR or nitrile bottom layer w/ a nitrile top layer). Thinking in terms of elasticity, which would explain why some mats (nitrile/nitrile) will lay flat once the stress of being on a roll is allowed to right itself (type of behavior we've observed). SBR isn't as elastic as nitrile however, so that could store stress during manufacture that prevents it from laying completely flat without mechanical help.

Or maybe we just got lucky.   

Hopefully after a few weeks it'll iron itself out. This is a table in an apartment so using spray paint isn't the best idea. I purchased the mat from here: http://www.esdproduct.com/esd_rubber_mats.php

[nanofrog]

If Its the same stuff I got at farnell (10 years ago) it will sort inself out, just takes a few weeks. 

This is what I'm accustomed to, even with far more recent vintage.

I wonder if it's to do with the actual type of rubber being used for each layer (i.e. SBR or nitrile bottom layer w/ a nitrile top layer). Thinking in terms of elasticity, which would explain why some mats (nitrile/nitrile) will lay flat once the stress of being on a roll is allowed to right itself (type of behavior we've observed). SBR isn't as elastic as nitrile however, so that could store stress during manufacture that prevents it from laying completely flat without mechanical help.

Or maybe we just got lucky.   

Hopefully after a few weeks it'll iron itself out. This is a table in an apartment so using spray paint isn't the best idea. I purchased the mat from here: http://www.esdproduct.com/esd_rubber_mats.php

If it doesn't, just use double sided cellophane tape (decent brand such as 3M or similar). 

[Psi]

I seem to remember some ESD mat manufactures saying you should leave the mat unfolded for a few days to let it relax.

[rdl]

I got mine used. It was fine at first - perfectly flat. It didn't develop ripples until after several months of use.

[GreyWoolfe]

My mat has to be at least 6 months old and is still perfectly flat.  I didn't know this could happen.  Is it common?

[nanofrog]

I got mine used. It was fine at first - perfectly flat. It didn't develop ripples until after several months of use.

If possible, can you elaborate on the conditions of your setup & specs on the mat, particularly on the materials it's made of (i.e. SBR, nitrile, or both)?

Just curious about how thickness and/or actual rubber used might be an indicator if they're going to ripple or not (i.e. create a bit of a buyer's guide or something past "get a 2 layer rubber mat").

TIA. 

My mat has to be at least 6 months old and is still perfectly flat.  I didn't know this could happen.  Is it common?

Not in my experience (work or personal), but I'm definitely curious with my newest mat (currently rolled up right now). 

FWIW, my older mat is 0.80" thick nitrile/nitrile (manufactured in Canada), newer is 0.60" thick (think it's also nitrile/nitrile, but have to check; COO = China, according to All-Spec).

Also, PM sent on an unrelated matter. 

[rdl]

I should probably clarify that what my mat does is more of a "bubble" than the ripples shown in the photo posted. It's as if the area that's used the most gets a little stretched and won't lay flat. I don't know who made the mat, I got it used from a place that does contract manufacturing. They replace their mats yearly and I got it for the price of shipping. It's probably vinyl and not rubber because it will melt, but it has a soft rubbery textured surface not smooth and hard like some vinyls are. It's the two layer type about 1.6mm thick.