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Forum topic by CudaDude posted 11-23-2012 06:05 PM 2282 views 1 time favorited 18 replies Add to Favorites Watch
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CudaDude

110 posts in 960 days


11-23-2012 06:05 PM

Did a search here and a google search and didn’t come up with a definitive answer. I’m building a play kitchen for my daughter and will be using 3/4 MDF for the paintability. My question is, what method of joining should I use? Can’t use the table saw yet so my options are dadoes and rabits with router, kreg pocket holes, biscuits or just normal right angle edge to face screwed together. Thanks in advance

Gary

-- Gary


18 replies so far

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Gene Howe

5626 posts in 2080 days


#1 posted 11-23-2012 06:25 PM

I’d suggest dadoes and and rabbets. IMO, biscuits add little strength to a joint. Good for alignment, though.
Also, you’ll want to apply a skim coat of glue on the raw edges, let it dry and then glue and clamp. The skim coat prevents the subsequent glue from soaking in to the porous MDF and starving the joint. The same applies when gluing end grain of any wood.

-- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton

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Loren

7543 posts in 2299 days


#2 posted 11-23-2012 06:28 PM

Biscuits or dados will be more predictable for you if you just
want to do this one project and have clamps to close the
joints.

MDF can be screwed together but it requires meticulous
predrilling of holes to avoid splitting the MDF. One way to
split the difference is to biscuit and glue, then quickly
drill and screw to clamp the parts. You still have to
carefully matching your drill and screw sizes/threads to
avoid splitting.

Many people do it, but I don’t recommend pocket screwing
MDF, especially in flush joints.

-- http://lawoodworking.com

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BTimmons

2123 posts in 1136 days


#3 posted 11-23-2012 08:09 PM

Good advice so far. But since it hasn’t been mentioned already, use eye protection and a good dust mask, along with any dust collection system you may have. MDF dust is super funky toxic stuff that you don’t need anywhere near your lungs.

-- Brian Timmons - http://www.BigTWoodworks.com

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teejk

1215 posts in 1336 days


#4 posted 11-23-2012 08:33 PM

MDF for a box that might get some movement? It’s pretty finely compressed sawdust that works great for tops and panels attached to some real wood but on its own I’d be concerned about fastener tear-out. I’d probably go rabbet joinery with glue and a boat-load of nails.

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MrRon

2830 posts in 1895 days


#5 posted 11-23-2012 09:35 PM

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CudaDude

110 posts in 960 days


#6 posted 11-23-2012 10:25 PM

Thanks for the links MrRon. Seriously considering going that route since it will give me the ability to break it down for storage once she outgrows it. Having never designed anything with these barrel nuts, would I need the centered or offset?

-- Gary

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waho6o9

4910 posts in 1228 days


#7 posted 11-23-2012 10:32 PM

MDO (medium density overlay) might be used as well.

It paints up nicer than MDF.

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David Dean

521 posts in 1550 days


#8 posted 11-24-2012 12:39 AM

Well Gary do you have a kregjig I build everything with my K-2 its easyer to use the a biscuits or dados and remeber to set the cluth on your drill to 6 or 7 and use a nickle and a dime to set your stop collar the dime is for more meat to screw into.

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cracknpop

93 posts in 1000 days


#9 posted 11-24-2012 04:46 AM

I have used both biscuits and Kreg pocket hole jig when building some cabinets and jigs for the shop. If I were making something from MDF today, I would use my Kreg pocket hole jig for the ease and speed of getting the job done. I echo David Dean’s comment regarding setting the clutch on your driver to avoid stripping out the screws. Good luck and have fun.

-- Rick

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MrRon

2830 posts in 1895 days


#10 posted 11-24-2012 10:16 PM

Cudadude; Either one would work as long as the thickness of the material is 3/4” or more. If under 3/4”, use the centered barrel nut. I haven’t used a Kreg jig, so I don’t know if they have screws suitable for MDF.

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teejk

1215 posts in 1336 days


#11 posted 11-24-2012 11:11 PM

I still would be concerned about tear-out in MDF…”skin” side probably fine but the raw side that it screws into???

If you want to be able to dismantle, then inside corner cleats made of whatever wood you have. MDF gets attached to them rather than to another piece of MDF.

View TeamTurpin's profile

TeamTurpin

85 posts in 713 days


#12 posted 11-24-2012 11:34 PM

I’ve not worked with MDF much until this weekend. I’m replacing my TS extension plates with a router table on the left and a larger table on the right. The router table is made from three layers of MDF that will be topped with formica. The other table will have an MDF/formica top, but will not be quite that thick.

I was not prepared for how much dust MDF creates. I had the vacuum and air scrubber going most of the time, but still the shop filled with fine paper dust. It’s everywhere. When this little project is over, I’m going to have to wash down the entire shop.

-- http://www.teamturpin.org/house/shop.htm

View DaveFFMedic's profile

DaveFFMedic

67 posts in 818 days


#13 posted 11-24-2012 11:40 PM

I built a TV stand out of MDF about 6 years ago and it still stands today. I would suggest hand-screwing the screws. If you take your time and pay attention you can get a sense of just how much torque the MDF can take before splitting or striping out the screw.

I used all butt joints.

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Kreegan

1452 posts in 798 days


#14 posted 11-24-2012 11:40 PM

MDF is not fit for man or beast. Nasty, cancer causing, formaldehyde infested stuff.

Rich;)

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CudaDude

110 posts in 960 days


#15 posted 11-25-2012 03:08 AM

Had some pieces of MDF laying around so I did some experimenting with the kreg jig. Doesn’t seem to be a question of strength with a edge to face joint even before the glue dried.

I’ll try to explain the problem I’m having. On the face part of the joint that I’m screwing into, I need to drill a pilot hole at the same angle of the pocket hole to keep the MDF from pulling up between the joint. Any suggestions on how I might drill the pilot holes at that angle?

-- Gary

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