mdf not staying flat
11/17/22
we are in the middle of a large job with slab door's we orderd maple with an mdf core, when it came in we left it laying flat over the weekend when we came in on Monday noticed that some sheets had a slight bow or curl to them as we where loading onto the panel saw. we are in Texas witch is a high hummidity , had some recent extreme temperture changes. has anyone else seen this? we have had this problem before i thought this was the whole purpose of mdf i is supposed to have a stable core.
11/17/22 #2: mdf not staying flat ...
MDF is relatively stable but it still moves. Up here in Ottawa Canada if you leave freshly pressed sheet goods laying with one face exposed overnight they will bow. Especially this time of year. It is always good practice to have a cover sheet on top of the stack.
I think that MDF has residual moisture from its production. We may be noticing this more now since lifts of MDF don't sit around in warehouses anymore because it is in such demand.
11/17/22 #3: mdf not staying flat ...
Tom has it right. MDF will curl just like solid hardwood panels if the humidity rapidly changes in a short period of time and air can't get all around the material.
11/18/22 #4: mdf not staying flat ...
Thank's guy's ... dam Texas weather one extreme to the next!!
11/18/22 #5: mdf not staying flat ...
Slight weather change and here is my spoil board... 1 day. Add in the skins and its a free for all. We do a good bit of MDF carved panels, full sheets, keeping the stuff flat is only possible by cutting a grid relief on the back side.
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