MDF for rail and stiles?

[wayne ateser]

On a raised panel cabinet door thats 22 x 44", would 3/4" MDF provide adequate structure for the door if used for the rail and stiles also? The rail and stiles are 3" wide.

It would use MDF for the raised panel and rather then a floating panel (as is necessary for a solid wood door), the panel would be glued all around the 4 edges providing added structural strength. Further, I think this also would use 3 hinges when using the Blum type hidden hinges.

I could use cheap dry 2x4 milled to size also for the rail and stile, but sticking with MDF would reduce the work load.

Any thoughts of your experience are appreciated.

[Jim Becker]

MDF for the panels...fine. But the rails and stiles will be better served with pine, poplar, maple or whatever hardwood you prefer. The issue with using MDF for your rails and stiles is that it doesn't take "normal" fasteners well and that becomes problematic when it comes to hinging, etc. There are ways to mitigate, but they add to the work load, not reduce it.

Do NOT use construction lumber like re-milled 2x4..."Kiln dried" in construction lumber means it's just south of dripping wet. You want material under 12% MC which will cover both air-dried and KD hardwoods.

[John Gregory]

I have not made doors from MDF, but two considerations would be weight. 22"X44" is a good chunk of MDF. Second, I worry about the ability of MDF to hold screws well and hence the hinges. I have heard that they made some light weight MDF now. You might check on that.

[glenn bradley]

I have made partially supported 'false fronts' from MDF (about 12" x 22") they did lose integrity (read warped, sagged, whatever) and need to be replaced. MDF panels, as mentioned, should be fine but I would not frame with it. Just my experience.

[frank shic]

wayne, i've recently built 39 doors and drawer fronts ENTIRELY out of MDF. the largest doors were approximately 14" x 48" tall. making everything out of MDF does cut down on the rough stock preparation but make sure you've got EXCELLENT dust collection. i recently bought a mini-cyclone from clear-vue just to handle this project and it would fill up a five gallon drum pretty quickly. use plenty of glue to fix the center panel to the rails and stiles (no worries about expansion here, right?). prime the door with an oil based primer. recently, i've been having much better results with an AIRLESS sprayer from wagner instead of the HVLP conversion gun. make sure you use at least three if not four hinges to support the weight. i'd recommend the INSERTA hinges from blum so that you don't have to worry about screws pulling out later. instead of making them with traditional cope and stick router cutters, you may want to check out the faux raised panel bits that are available from whiteside router bits. john lucas's website: woodshopdemos has an excellent tutorial on how to do this. yeh, i know the corners look routed, but if you use a 1/8" straight router bit you can make the corner look a little less round. did i already mention that you better have EXCELLENT dust collection? wear that respirator, ok?

[wayne ateser]

Thanks all. All great tips. I checked out kiln dried fir at HD today and thought they were a bit heavy for dry...so I see you point.! I definately go with solid wood rail and stile and all set up to do that and I know how. These are big doors and screws holding would be worrisome.
FYI:
Fir 1x4 at HD was was $0.43 bd ft (resawn 2x4, kiln dry)
Next cheapest, at HD anyway,
white pine, 1x4 select @ $2.62bd ft.
red oak 1x4 @ $5.85bd ft.
Red Oak 4/4 from Local lumber store (Reel Lumber) was $2.63 bd ft I know from last purchase.
MDF 4 x 8 was $25.95.

Ill check out the lumber yard as probably poplar is cheaper then and as oak is same as white pine, an obvious lumber store purchase.

Is poplar usually the least expensive paint grade lumber?
thanks for the great tips

[wayne ateser]

wayne, i've recently built 39 doors and drawer fronts ENTIRELY out of MDF. the largest doors were approximately 14" x 48" tall. making everything out of MDF does cut down on the rough stock preparation but make sure you've got EXCELLENT dust collection. i recently bought a mini-cyclone from clear-vue just to handle this project and it would fill up a five gallon drum pretty quickly. use plenty of glue to fix the center panel to the rails and stiles (no worries about expansion here, right?). prime the door with an oil based primer. recently, i've been having much better results with an AIRLESS sprayer from wagner instead of the HVLP conversion gun. make sure you use at least three if not four hinges to support the weight. i'd recommend the INSERTA hinges from blum so that you don't have to worry about screws pulling out later. instead of making them with traditional cope and stick router cutters, you may want to check out the faux raised panel bits that are available from whiteside router bits. john lucas's website: woodshopdemos has an excellent tutorial on how to do this. yeh, i know the corners look routed, but if you use a 1/8" straight router bit you can make the corner look a little less round. did i already mention that you better have EXCELLENT dust collection? wear that respirator, ok?
Good input. I know dust will be prodigous with MDF. I dont have a good dust collection (shop vac on table saw and router table) but I usually open the garage door and point a 20" fan outwards to help blow outside the stuff that gets in the air.

[Dan Gill]

I just made four doors with MDF panels and pile rails and stiles. I have a dust collection setup on my router table fence. Interestingly enough, the dust collector sucked up every bit of the dust from raising the panels. I've never had so little dust (and of course, no chips) when raising panels. I guess the MDF dust was fine enough for the collector to get it all.

I have 2hp HF collector, with a 4" hose necked down to a 2" opening in the back of the router table fence.

[frank shic]

wayne, a fan blowing out the garage door is not going to do the trick! i would seriously recommend investing in one of the minicyclones if you're really going to try machining that much MDF - a shop vac is more than adequate to work with it. make sure you've got dust collection hoses attached below the router and behind the fence - even this will not get 100% of it. the MDF dust gets ALL OVER the place and sticks to everything. make sure you wear a respirator on this one!

[Jim Becker]

One other thing about MDF dust...when you consider how the stuff is made, there is a lot of non-wood material in that dust. The resins can be nasty to both your cutters and your lungs. Even with excellent dust collection at the source, it's important to wear personal protection when working with this material.

[Dan Gill]

One other thing about MDF dust...when you consider how the stuff is made, there is a lot of non-wood material in that dust. The resins can be nasty to both your cutters and your lungs. Even with excellent dust collection at the source, it's important to wear personal protection when working with this material.

Ditto Jim. I always wear a mask when cutting MDF.

[Loren Hedahl]

You could drill perpendicular to the screw hole placements and glue in cross-dowels. That way the screws would have some good wood to bite into.

I do this often in repairing cases and action support work on old pianos. It actually is better than when new.

Loren

[Jim Becker]

You could drill perpendicular to the screw hole placements and glue in cross-dowels. That way the screws would have some good wood to bite into.

This is one of the things I was obtusely referring to in one of my earlier posts. Doable, but adds work. You don't have to do this extra step if you use solid stock for the rails and stiles. That said, I also had forgot about the Inserta hinges from Blum. They do deal with the problem nicely on the door, although the frame side still potentially has less strength since it's still compression holding the plastic inserts into the drilled holes. (Ikea is using these in their kitchen cabinet boxes and they are really, really nice hinges. Fast, too.)