Replies

1. 
   Piffin | Jul 04, 2007 01:51pm | #1

   Are you sure that you mean MDO???
   That is a plywood with oaper overlay. I dson't think plywood would make a very good wood for milling like that.

   Did you mean MDF which is a fibreboard ?

   We mill a lot of our own trim stock from Poplar. One of my subs built a house for his own customer and he used MDF through-out. He liked theend product, but found that it burned up the bits and blades really fast. There are resins and bits of trash - staples, grit, etc, in the MDF and a different density thn natural wood.

   Subsequent reseaarch ( partly here - and I think in the sister forum Knots) taught us that the blades for the milling machine are cut at a different pitch for MDF thaan for wood in order to last. Not being willing to make the investment to regrind all of my blades, I have not purssued using MDF.

   I hate the dust from it anyways.
   There are some advantages to MDF but not enough to outweigh the disadvantages, IMO

    

    

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1. 
   KaneoheBay | Jul 04, 2007 09:28pm | #6

   Yes, I do mean MDO. Recently, I made a mailbox from the material and was impressed with the consistency of the interior plies. I didn't see any voids. That's what gave me the idea.

   I know others have used MDF to similar purposes, i.e., raised panels, etc. but I'm hesitant to use MDF because of the possiblity of the machined edges degrading over time.

   Thanks for your reply.

1. 
   Piffin | Jul 05, 2007 12:15am | #12

   well, then definitely stay away from MDO for moldings. It will splinter too much. The core is fir 

    

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1. 
   KaneoheBay | Jul 05, 2007 12:31am | #13

   Received a lot of helpful comments.

   Thanks

2. 
   DougU | Jul 05, 2007 01:13am | #14

   Piffin

   You'd know more about this then I, but couldnt he run Azek or some of the other manufactured "plastic" stuff for trim? I dont buy the stuff so I dont know what it costs. I do know that it can be profiled.  I also dont know what it'd do to the cutters, probably not nearly as much as what MDO or MDF does.

   I wouldnt even think of putting a profile on MDO, cant see where that would turn out good. 

   Doug

1. 
   Adrian | Jul 05, 2007 01:23am | #15

   Yeah, I definitely would never use MDO except for signage.Cabinetmaker/college woodworking instructor. Cape Breton, Nova Scotia.

2. 
   Piffin | Jul 05, 2007 01:34am | #16

   Azek is very easy to mill, doesn't bother the cutters at all.It does mill up with a somewhat furry finish though that needs sanding. I've use it quite a bit around showers and in bathrooom/kitchens as paint grade replacement for wood.But the cost is close to astrnomical. There are some offsets in that there is no waste, but he did mention cost was a concern for him.But it looks like he is in Hawaii and that somehow really skews the csts for various products. Maybe the stuff from china is cheaper and the stuf from NewHampshire is more expensive, so it might depend whether there is an Azek knock-off plant nearby 

    

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3. 
   KenHill3 | Jul 05, 2007 02:24am | #17

   EVERYTHING in Alohaland is more expensive just for the shipping and energy costs. I would also imagine that the tropical humidity must play a part in material selection. I wonder how well MDF does there?

4. 
   Jer | Jul 05, 2007 02:06pm | #19

   The only thing Azak does to the blades is create a buildup of residue plastic after some use. I take a few minutes and clean it with a razor.

2. 
   Sphere | Jul 04, 2007 01:52pm | #2

   Pretty good chance of voids in the core plys. Unlike Baltic Birch which is not as likely to have them.

   Finishing the edges would suck, and I'd bet router bits would dull rapidly from the huge amount of glue, which can be abrasive in nature.

   Now, just rips for say, battens or backer for dentil/crown pack out, might be an option.

   I'd not do it..there are plenty of better choices, IMO.

    

1. 
   KaneoheBay | Jul 04, 2007 09:32pm | #7

   Please see my reply to Piffin. I know some router bit mfrs cut their bits for different materials so that might be a solution to the glue problem.

   My only experience with MDO comes from cutting a single sheet of the material.

   Thanks.

1. 
   Sphere | Jul 04, 2007 09:40pm | #8

   If it were me to do, I'd glue size it on the exposed edges..Titebond III and sand, prime, sand,prime, sand, paint.

   That fir end grain is wicked hard to get smooth with a router that is even close to dull, and if you "burnish" with a dull bit, the primer/paint will swell everything out of proportion. The edge grain will fatten out, while the end grain plies do not..you'll get steps in the profile.

   That is all fine for outdoor signage ( of which I have made plenty) but for trim that you may actuall touch or see from less than 10' away...it depends.

   Have fun. 

1. 
   KaneoheBay | Jul 04, 2007 09:48pm | #10

   Appreciate your comments

    

3. 
   Jer | Jul 04, 2007 02:22pm | #3

   I'm pretty sure you must mean MDF like Piffin said which is a fiberboard and used quite a lot in making moldings.
   I have replaced 75% of all the ugly clamshell casing trim in my house with my own milled out version of a beaded edged flat, and have used nothing but MDF. It mills good, but as mentioned above is very messy and dulls your blades fast. The reason I used it was because of the price. I had a lot to do and I probably paid an eighth of what I would have for poplar. The other good thing about it is that there's no seasonal movement. Once it's in place it stays put.

   It's not the greatest stuff in the world to work with, it has a bit of a learning curve. I much prefer wood, but the price was really worth it to me.

   I don't have that much more to do and I think I am going to treat myself to having a local mill shop do the rest.

1. 
   Piffin | Jul 04, 2007 02:32pm | #4

   I don't think there is mucch of a diffeerence in price for me, but the advantage my guy was going for is to eliminate that seasonal movement.I simple beaded edge would be easy enough to do. Most of our work skins the whole surface for the style of casings we do, so I guess it would matter what style he has in mind.And I would not mind throwing away/replacing fifty dollar router bits as much as regrinding $250 blades for my Williams and Hussey 

    

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1. 
   Adrian | Jul 04, 2007 02:52pm | #5

   I agree with the others....MDO wouldn't be a good material for mouldings, even rips as the edges would be exposed. MDF is a better product. I think MDF makes excellent mouldings in many situations, but I rarely make my own now.....I use a company that specialises in it: full 3/4" or thicker (I don't use the thin stuff), and they use moulding grade MDF which is very different from the usual stuff....more consistent. Regular MDF has slightly coarser particles towards the centre which are exposed when the profile is cut....moulding grade is consistent all the way through. I find not all MDF moulding companies are the same....the good ones are very particular about their MDF, the others buy on price.

   I can get nice profiles, long lengths (12 footers are a pain in my home shop; 8 footers available also for standing trim), and it comes double-primed and ready to install. That's the way to go if you want MDF mouldings, IMO.

    Cabinetmaker/college woodworking instructor. Cape Breton, Nova Scotia.

2. 
   andybuildz | Jul 04, 2007 11:00pm | #11

   A $250 W&H blade? YIKES! One of my planer blades broke and they won't sell me just one and I thought those were expensive.

    

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2. 
   KaneoheBay | Jul 04, 2007 09:44pm | #9

   You mentioned price on your project and that's what got me started thinking about using MDO. For example, 1x2 unmachined stock of poplar runs about $1.10/LF (in Honolulu) compared to $0.27/LF for the ripped MDO. Quite a substantial savings.

   My upcoming project will require hundreds of LF. The budget is a high concern.

   Thanks.

    

4. 
   user-246028 | Jul 05, 2007 04:05am | #18

   In my area, MDO is generally used for making signage etc. for outdoor use. I don't imagine there would be a problem making trim out it. I'm just a little old fashioned I suppose. I like good old fashioned wood. I'm funny that way.

   Dave