MDF Fastener question

[bonesbr549]

I'm finishing a wine cabinet and the top will be a 14" x 17"  veneered (bubinga on top backer is cherry) wrapped with cherry (1 1/4") To attach it to the top of the wine cabinet,  I'll be screwing(or something)  up through a  7/8" x 2 cherry stretcher into the bottom of the veneer panel to hold it to the cabinet.    The problem I have is since this fastening point will be MDF (the core of the panel), what is the reccomened fastener?  I looked at McFeeley's and they reccomended Confirmat screws for MDF.  What would You use?  I considered changing the core to Ply so I could use wood screws, but all I've researched the MDF is the best for a veneered panel.  I'm doing two of these wine cabinets (1 for the wife and one for a client).  Thanks in advance. 

 

[jmbfestool]

I find screws with a less but larger thread hold the best in MDF.  

Drill hole slightly bigger than the screw through the cherry stretcher and then screw straight into the MDF and it will pull tight works for me any way.

Spax and Ultimate screws are fine to use they have cutting tip end helps it cut into MDF

JMB

 

[wnagle]

I would suggest conformat screws as well or Miller dowels if the end grain dowel will be aesthetically pleasing.  BUT be gentle when you tap them in as they bottom out.  Miller dowels hold very well in my opinion, but can out lateral pressure on the mdf if you hit them too hard as they bottom out.

 

[jmbfestool]

I have not used them YET!  but it says they are for MDF use  are the NEW PASLODE PROSCREWS

http://www.angliatoolcentre.co.uk/paslode-pro-screws-metal-selection-case-137995-pid36698.html

 

[junk731]

I've used Kreg Coarse Pan Head pocket hole screws in similar applications but I pre-drill with a tapered drill bit first even if the screw has a cutter. The pre-drilling is more important when screwing into the edge of MDF. The screws works like a wedge and will split the material. They also work well with particle core and plywood.

John

 

[bionicus]

#8 sheet metal screws with a 7/64" pilot hole, as long as possible. They thread into MDF much like confirmats, whereas wood screws tend to chew up the hole and fibers.

 

[jmbfestool]

I've used Kreg Coarse Pan Head pocket hole screws in similar applications but I pre-drill with a tapered drill bit first even if the screw has a cutter. The pre-drilling is more important when screwing into the edge of MDF. The screws works like a wedge and will split the material. They also work well with particle core and plywood.

John

YES  always pilot hole in the edge of MDF as it will nearly always split the MDF apart.  When screwing in to the edge you want drill at least the same depth as the screw and the hole same size as the screws core size so just the thread is whats bigger than hole and I try and use long screws as smaller screws can spin in high torque thats why the large threaded screws hold better.

I  think bonesbr549 will be screwing into face of the MDF from underneath so no pilot hole is needed with a cutter screw well that whats I ment with the cutter any way. Well I never pilot hole the face of MDF their is no need the screws hold well.

JMB

JMB

 

[Roseland]

I find the best fix into MDF is using insert nuts, such as these:

http://www.screwfix.com/prods/59937/Fixings/Furniture-Fixings/Insert-Nut-M6-Pack-of-50

Countersink the hole you drill (8mm for the 6mm ones) slightly, screw the nut in with an Allen key and it will be completely flush.  You then use a 6mm bolt to fix the top down.

The very coarse thread gives a strong fix.

I hope this helps.

Andrew

 

[junk731]

Bionicus

Regular wood screws will do what yours saying but deep root coarse screws like the Kreg screws and Spax won't in my experience.

JMB

Totally agree, I pre-drill everything probably more out of habit. One other thought, on edges keep about 2" away from corners because of potential splitting.

John

 

[bonesbr549]

Thanks to all for the suggestions.  I'll look at each of them.  I will be screwing into the face of the MDF not the edge so thats a little better than the edge.  The edge will get domino's to hold the cherry edging.