Replies

1. 
   ring | Apr 02, 2008 04:42pm | #1

   Nathan,

   We very regularly use 8mm MDF as the substrate for flat veneered panels. Its flatness and uniform thickness is much better than ply for this purpose. After veneering it comes out just over 9 mm thick, and we use a slight rabbet on the back to fit the grooves. (we use 8 mm grooves, but I'd do it the same way if they were 1/4")

   David Ring

   http://www.touchwood.co.il/?id=1&lang=e

1. 
   coolbreeze | Apr 02, 2008 05:08pm | #3

   I just finished a set of doors using maple beadboard. I bought  new S & R bits and they worked perfectly. MDF has a bad name in my area because of the publicity that the level of formaldehyde found in the FEMA trailers that contains a lot of MDF. FEMA is testing the trailers and moving people to hotel rooms when the formaldehyde levels are found to be high.

   For my purpose, I was glad that I did not have to use MDF because there would have been a fair amount and I detest the dust made by MDF. MDF is also dulls the bit quickly, IMHO.

1. 
   ring | Apr 02, 2008 05:45pm | #6

   Regarding the formaldehyde, I don't really know.  My shop uses ply for all the construction parts of cabinets, but for door panels the MDF has serious advantages.  I don't think that as part of a kitchen the quantity of MDF we use really poses a hazard, but again, I have no scientific evidence either way.

   Nobody likes the dust and odor, but hey, for me this is a business.  Our TS blades get sharpened once every 2 weeks anyway.  And again, I couldn't say what's harder on them - cutting ply sheets with HPL faces or MDF.  My blades work hard for a living, and cutting MDF is part of the job description.David Ring

   http://www.touchwood.co.il/?id=1&lang=e

2. 
   saschafer | Apr 02, 2008 07:13pm | #8

   I think the FEMA formadehyde was more from plywood and particleboard than from MDF. In any case, you can get MDF that's made without any formaldehyde-emitting adhesives (Medite is one vendor).

   -Steve

    

1. 
   coolbreeze | Apr 03, 2008 02:34am | #9

   I was not aware that there was formaldehyde in plywood. Is there a way to tell? The plywood I get has no labels on them at all.

1. 
   saschafer | Apr 03, 2008 03:50am | #11

   As with MDF and other manmade panels, the formaldehyde is emitted by the adhesive as it cures. It gradually outgasses over time, so by the time you get the panel, there's usually not that much left. But if you get a "fresh" panel, or one that's been manufactured using high-formaldehyde adhesives, then the amount of formaldehyde outgassing can be significant. (That was the main problem with the FEMA trailers--they were manufactured quickly, from recently-fabricated, high-formaldehyde panels, and then occupied immediately, which meant that the formaldehyde levels were much, much higher than they would have been under a normal manufacturing schedule.) There do exist standards for formaldehyde emission limits, but they relate primarily to occupational exposure; I don't know if there is a standard for maximum formaldehyde emission of a plywood or other panel at the retail point of sale.

   Columbia Forest Products recently switched to a zero-formaldehyde adhesive in their plywood (another example of their already impressive commitment to safety and environmental concerns).

   -Steve

    

2. 
   oldusty | Apr 03, 2008 04:23am | #12

       Steve ,

            Here is a perfect example of the level of exposure that can occur , allegedly from the FMDH . FEMA has indicated  there are no indoor air standards to conform to , only occupational levels at the factories .

           Yet I believe FEMA is The agency who has forbidden occupancy based on the indoor air quality , hmmm ???

                 dusty

3. 
   blewcrowe | Apr 03, 2008 02:52pm | #13

   not aware that there was formaldehyde in plywood. Is there a way to tell?.........

    

   Taste it.

2. 
   Nathan Barnard | Apr 02, 2008 05:21pm | #4

   Isn't that a lot of work to veneer your own mdf sheets? That's one of the reasons I am interested in pre-veneered plywood. My supplier tells me they have 5.53mm (.218") ply, but wouldn't that be too thin? Even with pins to hold it would there be a sightly gap where it meets the rails/styles?

1. 
   ring | Apr 02, 2008 06:05pm | #7

   Nathan,

   I sub-contract the veneering to someone with a large press.  It only costs me about $5 per side not including the cost of the veneer (we do full sheets only).  Then we cut the sheets to size on the TS with a scoring blade. 

   If your ply is really 5.5 mm (including the veneer) then personally I'd go to the next thicker option.  The cost difference is probably inconsequential.   That said, for normal sized doors your 5.5 mm should be enough for life under calm conditions.  In my shop we make all our cabinet doors 22 mm thick (7/8") with the panels 9 mm as I said.  I like the "clunk" of them better, and we don't have to worry about special cases of wide doors or kids riding their tricycles into the cabinet doors.

    David Ring

   http://www.touchwood.co.il/?id=1&lang=e

2. 
   hammer1 | Apr 02, 2008 04:59pm | #2

   Since the panel will be plywood and won't move, I just put a couple 23 Ga. pins in the back. You can sneak them in like a toe nail and they don't show. They keep the panel tight to the front and eliminate rattling. You could use short brads, too. It doesn't seem to matter what size bits you get, plywood always varies over time and won't fit perfectly anyway.

   Beat it to fit / Paint it to match

   
3. 
   oldusty | Apr 02, 2008 05:41pm | #5

     Nathan ,

               For standard sized cabinet doors 1/4" panels are fine .

          You need to ask you supplier for what we call true 1/4" thickness in the specie you want , typically they will have it .

        Many of the frame and panel doors I run have a square edge as opposed to a profile around the inside edge. I adjust the groove to fit the panel material that occasionally comes in at 5.2mm a fat 3/16" . I make most of these on the TS .

     So if you can use a square edge frame use the TS and make them fit perfect.

         I have put the thin panels in a 1/4" groove and pinned them forward from the back , but as your concern there will be a gap behind the panel . When I need the profile shaper detailed edge I use what I have to and pin if needed.

                dusty

4. 
   sfmc | Apr 03, 2008 03:18am | #10

   Use your raised panel bit and just put the flat back toward the show side. It makes a sturdier panel than just the 1/4 inch plywood.

    

   We get to soon oldt und to late schmart