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Forum topic by EastoftheDitch posted 08-07-2012 04:12 PM 1134 views 0 times favorited 9 replies Add to Favorites Watch
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EastoftheDitch

14 posts in 1329 days


08-07-2012 04:12 PM

I hope this is the right place for this posting, as it’s my first on this forum -

I’m setting up a shop for my “retirement” hobby – hopefully creating something more useful than designer sawdust. My first project is making the Wood magazine’s Mobile Tool Cabinet – actually two of them. I’ll be so glad to get my stuff organized so I don’t have to remember which box I stored it in.

The project called for 3/4” Baltic Birch plywood, but being the cheapskate I am, I picked up 5 sheets of 3/4 MDF at the Habitat ReStore for $10/sheet. I hope I haven’t sabotaged my plan already by not using the Birch Ply since I’ve already cut all the pieces for assembly.

First question – I have a new Kreg pocket jig which I have enjoyed for the lack of gluing and clamping. Will this technique work for assembly with their 1 1/4” coarse thread pocket screws? I’m not sure what kind of glue I would even use on the slick pre finished maple colored surface.

Second question – the shelves are 4 1/8” and 10 1/2” 3/4” MDF 22 1/8” long on adjustable steel shelf standards. The plans call for a 1 1/4” edging ripped from the same material as the shelves. I have a couple of problems with that -

a – the rip edge that will be showing will look pretty nasty for a finished product
b- I was thinking of an iron on edge banding but wonder if I will actually need the structural support of the edging on a shelf that is less than 2’ long.
c – if I use some real wood – pine or birch for the edging, I’m afraid the texture of the finish will stand out even if painted; well maybe not if I get clear stock. Your thoughts?

Third – The finish on the panels don’t all match so I was thinking of painting the interior and exterior different colors (tan and burgundy) but was wondering if paint would adhere to the slick surface. Any special primer or paint type you could recommend? Also – if I go the edge banding route is there a paint grade veneer so I don’‘t have to paint over some prefinished cherry banding.

Well I guess that’s it for now. At least I made my insomnia productive, just in time for my wife to get up so we can go to the gym and try to keep these decaying bodies working as long as we can.

Thanks in advance -

Marc


9 replies so far

View DS's profile

DS

2132 posts in 1139 days


#1 posted 08-07-2012 04:32 PM

Marc, sounds like you are off on the right foot by getting organised in your shop.

I have no problem with MDF cabinets. MDF paints well and can make a clean project.
Unfortunately, Kreg screws and MDF aren’t very good friends. The head of the screw will tend to split out the layers of MDF at the head rather than tighten down. Even screwing into the edge of an MDF panel through a side panel will tend to delaminate it. This can work well if, say the shelf is dadoed into the sides and then screwed, as the mdf thickness is contained in the dado and has no room to split out. Since this is going to be painted, 1-3/4” long 18awg brads would work fine – just use with a good glue (TB II or equiv.) and fill in the heads with filler afterwards.

As far as edging goes, Pine edging on a MDF shelf that will be painted can work very nicely. My preference is a hardwood like Alder, or Poplar, but this is not of much consequence on a shop cabinet. Filler and sanding will make the joint dissappear nearly completely.

Iron on banding is all about the same price for wood, regardless if it is Cherry, Maple or almost anything else. If you’ve got some surplus on the shelf, use it. No sense spending money on paper tape if you have surplus sitting around.

For finishing, a good primer or sealer will cure your MDF ills. Once it is primed and sanded, your choice of finish will complete the project nicely.

You’re on the right track. Stick to it. Take some pictures and share your experience with us here.
And, oh yeah, welcome to Lumberjocks.

-- "Hard work is not defined by the difficulty of the task as much as a person's desire to perform it.", DS251

View huff's profile

huff

2807 posts in 2004 days


#2 posted 08-07-2012 04:35 PM

Marc, I usually don’t work with MDF, but I don’t see why your project won’t turn out great using it. The great thing about using MDF is it doesn’t matter about grain direction, so you can maximize your usage on each sheet. I would recommend you edge the front edge of each shelf with the 1 1/4” strip.(MDF would work fine) Since you are going to paint it, you can glue and nail the edging in place and when you sand it, the seam should pretty well dissapear. The one thing to remember about finishing MDF is the end cuts are very porous and will soak up finish like cracy untill it’s totally sealed. When you finish, use a good primer first to seal it completely and sand it before you apply your final coat. You should be able to finish both sides of the MDF to look the same if you lighly sand all surfaces and prime it first. You can use pocket screws with MDF, but you have to be really careful. Make sure you glue each joint and be very careful when running your screws in. They will tend to pull in too far and pucker the area around the head of the screw. Run your screws in slowly and only pull the joint together just enough to make it snug. I would recommend you play with a couple pieces of scrap MDF first to get the feel of what can go wrong when working with the pocket screws.

-- John @ http://www.thehuffordfurnituregroup.com

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EastoftheDitch

14 posts in 1329 days


#3 posted 08-08-2012 03:07 AM

Great suggestions and so timely. I spoke with the folks at Woodcraft and they seemed confident that the coarse thread will work fine on the MDF. The fine thread would probably strip out. I think what I will do is a 3/16 dado where the shelves will sit and drill a 1/4” hole from the outside and glue and drive 2 – 1/4” dowels in each side. Since they are going to be painted. I can fill and finish and nobody should know. For the other joints, I’ll stick with the Kreg anchors (hey I just got the kit and I want to use it) .
I’m at the beginning of my learning curve and shop storage seems a good place to start before I rip out the kitchen cabinets and the tuition will be a whole lot less when I goof.
Will keep you posted and post pics when I finish.
Thanks all –
Marc

View CplSteel's profile

CplSteel

142 posts in 883 days


#4 posted 08-08-2012 06:05 AM

One word: confirmat. Everyone that uses them seems to like them quite a bit.

View skipj's profile

skipj

73 posts in 991 days


#5 posted 08-08-2012 11:07 AM

Plus 1 on confirmat, only way to go. Order the starter kit from Mcfeely’s and go to it.

View EastoftheDitch's profile

EastoftheDitch

14 posts in 1329 days


#6 posted 08-08-2012 11:50 AM

Thanks guys for the tip – the confirmat looks like the way to go. Too bad I bought 1000 of the course thread Kreg screws yesterday. Anyway – to drill the holes at the right angle, does the conformat drill bit fit the guide in the Kreg pocket jig, or is there another tool I will need to use them?

TIA

Marc

View Gerald6279's profile

Gerald6279

18 posts in 1497 days


#7 posted 08-08-2012 12:17 PM

Don’t regret buying the Kreg screws as you’ll use them sooner than you think. I looked at the plan online and suggest that, when you get the confirmat kit, drill in straight to join the pieces because MDF would be weakened at an angle causing it to be more likely to fail with a load on it. Since you plan on painting anyway the screw holes could be filled with a little filler and sanded before paint and only you would know. Since it is for your workshop you would want the extra strength to avoid damaging your tools from an MDF failure. With the confirmat and good glue it will be a very sturdy project after completion. As for a special tool the kit comes with the drill bit and just good ol’ eyesight should suffice on the drilling.

-- Gary, Indianapolis

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MrRon

2928 posts in 1962 days


#8 posted 08-08-2012 04:46 PM

When you drill through MDF, the hole on the backside will be bulged and keep the joint from making good contact. Use a c’sink to remove the burr before screwing it together.

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EastoftheDitch

14 posts in 1329 days


#9 posted 08-08-2012 08:40 PM

Thanks again for the ongoing tips. With enough advice maybe I will be able to make my first project PERFECTLY!

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