# Questions about cutting and drilling MDF, and glueing terracotta pots to it



## Smile_n_Nod (Jan 20, 2011)

My wife will be in charge of a VBS project next week. The goal is for the kids to make little flag holders by gluing a small terracotta pot upside down onto a piece of MDF (the flag-sticks will go down through a hole in the base of the pot and into a hole in the MDF).

She has asked me to make 175+ little MDF squares, and I need a little advice before I proceed.

I can cut well over 200 4"x4" squares from a single 8'x4' sheet of MDF. I have a portable table saw that I can wheel outside to make the cuts on my well-ventilated lawn, so I don't see any problems there.

Next, I will need to drill a hole in the center of each square. I have a bench-top drill press with a table and fence that I can clamp a stop to, so drilling the holes in the center of each board should be straightforward. The only difficulty is that the drill press is located in my under-ventilated garage, so I'm planning to set up a shop-vac to suck up the MDF dust as the holes are drilled. The garage is going to be hot, but I'll shut off the drill press and shop-vac periodically to prevent overheating.

Here are my questions:

1) My saw blade is the factory model that came with the Ridgid r4510 table saw. Will it hold up while making almost 200 linear feet of cuts through the MDF? Should I buy a special blade for cutting MDF?

2) Will my drill press have any problems using a standard drill bit (1/4" or smaller) to make 175+ holes in the MDF? Is a standard drill bit okay?

3) Can MDF be "glued to"? What kind of glue can the kids use to stick the terracotta pots onto the MDF? (It's a project for grade-schoolers, so two-part epoxy and noxious fumes are out.) Any idea if hot glue will work?

Thanks for any feedback.


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## LeeBarker (Aug 6, 2010)

Hi SNN-sounds like a worthy project. You did not say how thick the MDF is. The stuff is heavy. Will you be able to cut it into manageable pieces with a skillsaw first? I wouldn't want to work on a small table saw with a whole sheet of MDF.

Drilling the holes in the MDF will not present a dust problem. I wouldn't even fuss with the shop vac. A fan blowing air across your face would feel pleasant and be a lot quieter.

An ordinary drill bit will do. MDF chips are fine, so they tend to clog the bit. You might develop a rhythm of drilling, backing the bit out, and drill some more to keep the bit from getting too hot.

Any blade will cut MDF, but a combination blade does the best job of getting rid of the chips (and yes, there is plenty of dust too). You might get a little roughness on the bottom side of the cut.

When you make your L-shaped stop for the drill press, you might put a piece of 1/4 inch stock on the bottom, leaving a "gutter" where the chips can gather so you don't have to clean the table off every time.

As for gluing to the MDF: Hot melt will work well, but would that be advisable around these kids? Construction adhesive is smelly but it would do the job. You need something with mastic consistency. Maybe there's a latex adhesive caulk that would work that wouldn't stink. It's worth some experimenting. Build some and see if they break! (That's where the extra 25 come in.)

Kindly,

Lee


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## Loren (May 30, 2008)

2) I'd use a cabinet-maker's or brad-point drill. The exit hole will be
cleaner and walking of the bit is eliminated.

I just grind standard metal drills to a cabinet-maker point.


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## Jahness (Nov 1, 2010)

Alex Plus would work great to adhere the pots to the MDF. Put a little at the edge of the pot then around the rim of the pot where it meets the MDF, kinda like sealing a toilet. Alex Plus is caulking with silicone mixed into it but it won't smell like silicone. You can buy it at Home Depot.


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## Smile_n_Nod (Jan 20, 2011)

Thanks everyone. I cut the squares (out of 1/4" MDF) on my table saw and zipped 'em out in no time. My wife passed on the idea of drilling holes in the centers, and she's still undecided about the adhesives. It's her project, so she gets to decide.


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