Guys,
I’m installing 7-1/4 inch crown in a house with forced hot air heat. The same crown was installed in the foyer in poplar and shows seasonal gaps along the ceilings (not in the joints). I can get the profile in MDF. 99% of my trim work is in poplar and I’ve never worked with large MDF moldings. I could go with poplar, but backprime, heavy nail, glue joints, etc. Or I could try the MDF. Any thoughts on which you would prefer? Only a 9 foot ceiling.
Thanks
FR
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Replies
personally I hate MDF and love polar.
MDF will flake at coped joints, does not play well with water and will show you gaps or bulges from thermal expansion/contraction lineally
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so you used it once, couldn't figure it out ... and it's junk?
MDF is just fine for trim and in some ways out performs wood.
it won't "flake" at copes ... if you know how to run a coping saw.
saying something that can be trimmed to perfecting with a shape utility knife is difficult to work with is just plain silly.
and aside from your one customer ... who had a water leak ...
how many other "crown incidents" have you experienced?
me ... uh ... none. Usually don't wash down the crown when we do the screens each spring.
"and will show you gaps or bulges from thermal expansion/contraction lineally"
I guess it would ... if it moved ... like wood.
"Buldges" ... get real ... or use a few more nails.
and what's with the gaps?
it's paint grade ... prime, caulk, paint.
aside from using enough nails to hold it tight ... use some caulk.
U know ... like all painted trim.
big wide crown is the perfect MDF project.
sign me up!
Jeff
Buck Construction
Artistry In Carpentry
Pittsburgh Pa
""and will show you gaps or bulges from thermal expansion/contraction lineally"I guess it would ... if it moved ... like wood."That is not an IF, Jeff, it is a definite. MDF moves in length which real wood does NOT do. It moves in responce to temperature, unlike wood.This knowledge is not just from my one use, but from seeing other jobs here and talking with subs. even a seven foot length of casing will shrink when it goes down to zero in winter enough to pop a paint joint. a 16 ' piece of crown makes a good 1/8" gapNone of that applies like I told Shep when you are in a moderate climate and living there year round, but it is a definite negative aspect in other places.glad to help with your education Grumpy.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I guess it's a good thing I live/work in a moderate climate ... Pittsburgh ... 98 in the summer and 0 in the winter.
MDF is a fine product and is a fantastic substitute to real wood for bigger build up crown.
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
sure it is in some places. Guess we knocked around all the pros and cons of it now eh?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I've installed miles of each and installed poplar in our own home. MDF looks like C R A P if you ask me. nice thing about it is you can bend it to fit where as Poplar it makes it a bit harder.ML
I second Piff...hate MDF.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
Another vote for Poplar.
Are there trusses above the ceiling where the gaps appear? Might not be the crown. Same thing could happen with MDF.
Everyone,I'm sticking with poplar. I'll pre/back prime, nail away and glue the joints. As always, thanks for all of the input. FR
Basswood,No trusses. I'm in NJ. Stick built all through. FR
I'm not crazy about MDF as a material, but I think that MDF crown is a pretty good use of the material. I've installed thousands of feet of it, and can only remember one callback.
A couple of tips- allow the material (this includes poplar, or whatever) to acclimate inside the house for several days before installing. Make sure you glue all the joints. I like Titebond's moulding glue. It doesn't drip (much), sets up pretty quickly, and seems to really bond the MDF well.
I generally cope even MDF, but you have to be careful when coping and installing to not to damage any thin sections. It doesn't have much, if any, strength.
my places probably see more thermal movement with seasons than a place that is lived in year round like yours.Truss lift is a possible concern here too like Basswood mentioned.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I could see the seasonal movement movement being a problem, but many of the people around here go from central heat right to AC, never opening the windows. So that's not much of a problem. We do get some humidity swings, from 90%+, down to 40% or so. But since folk in NJ don't seem to like fresh air, that's not a problem in homes.
Also, trusses are very rare in NJ. Pretty much everything is still stick built.
I really don't like using MDF for base or casing. It crumbles too easily. But I think its pretty good for crown, where it's not going to get banged into. Except for it being so wiggly, like someone else mentioned.
I've only used the stuff once, and the rest of the trim was all pine - stained, but the lady wanted to use MDF crown to save money. This was back in about '98 as I was ramping up and she was buying all materials.Two years later, she had a big water spill flood upstairs that flowed around the radiator heat line down and wetted the MDF crown below it, making it all puckered up and warty looking.She was all upset and I was not. Told her to buy more crown to match, and get it all ready ( she had prepainted the original) and call me to install it. said I'd cut her a price break.That warty #### is still there - 7-8 years now.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
LOL!
Yeah, well, most people don't plan on their ceilings flooding. <G>
I think the MDF crown I'm getting now is better than the older stuff from 10 years ago. I don't get the volcanoing the older stuff did when nailing, and the primer on it is a lot better than it used to be. It also seems to be a little denser.
BTW, I'm not trying to convince you to use the MDF. It's more like its interesting to compare the regional differences.
"But since folk in NJ don't seem to like fresh air,"Now that's funny!
Its a little known fact that the people of NJ have a highly developed sense of humor
<G>
Thanks for adding your input on MDF crown molding. I just did a bathroom and I was concerned about moisture affecting the molding. It's a large, well-ventilated bath so moisture may not be an issue. I made the customer aware of my concern and they still wanted to do it.
I had 2 main reasons for using MDF: 1) I've seen fingerjoints telegraph through in moist environments and 2) MDF is flexible enough that I was able to install continuous pieces without splices.
(BTW, check your email)
Hey Shep...can't remember if it was you or basswood...or who ever...doesn't matter who...who mentioned this glue gun http://www.rockler.com/product.cfm?page=6576 or something similar. I love glue guns. I use em' on a regular basis for all kinda different things but the ones sold in the store are all the cheap junky ones and with the frequency in which I use em' I'm real inclined to score this one soon.
I was wondering if you or anyone else uses them to glue your trim corners together instead of Elmers. I was thinking about it the other day when i had no spring clamps with me and I had to put a cpl of nails on the outside of one of the corners on one of the doors I was working on to keep the gap closed till the glue dried. Got to thinking how convenient it'd be to use a poly hot glue stick that dries within 30 secs on all my trim corners and scarfs....especially a cordless glue gun of high quality
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
Andy-
it wasn't me, but I've been curious about those glue guns, too.
I usually glue my miters with TiteBond moulding glue, and use a few Collins clamps to hold it together until the glue sets. Especially on outside crown miters. It gives me a little time to make sure everything is aligned.
Well I read all the reviews on that gun I could find...in Amazon and in the Rockler site and everyone loves it. Cpl of carps said the absolutly love it for CROWN!
Tha main comlaint was the glue in the gun becoming unusable if you don't cap it while not using it and capping it onto a hot tip means you need to wear gloves which is inconvienent but one guy had a solution for that....I dunno...you'll have to read em' yourself but overall even with that one complaint most everyone sounded like they didn't know how they lived with out it.....for the very reason we're talking about. No need for clamps. Dries rock hard within 30 secs with the ww30 tubes(ww means wood to wood). Read a review of gun and the reviewer allowed the joints on oak to fully cure...smashed it with a hammer and the wood broke but not where the glue joint was.
I might go for it if I see a sale. I checked Ebay and Googled it to death but it's about $120 for the kit (comes with thee tubes of glue and the case gun and charger).
One thing I used to do a lot was to put my elmers on the miters and leave a gap in the middle that I'd hit with a dab of hot glue from my cheapo gun to hold it together till the Elmers was hard.
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
Had another thought tonight...ut ohhhh....I was wondering what the advantages of using a poly glue gun might be over using 2P-10 thick being the 2P-10 thick dries hard in just a few seconds depending on whether or not you use the accelerator spray.
I also wondered why one might use a Collins clamp if the used 2P-10. Why one over the other???
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
If I used the 2p-10, I'd probably just hold the joint together until it set up, hoping that my fingers aren't also attached to the wood.
But I'm cheap. I like the TiteBond glue. With a couple of Collins clamps to keep everything tight, I've haven't had a problem.
Yeh...I just make everything too complicated and I think I like gadgety kinda products especially when they work .... at least I know my shortcomings : )~
elmers glue n clamps...how archaic...lol
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
I like gadgets, too. I have a Prazi putty chaser LOL
But sometimes old-fashioned works best
I like gadgets, too. I have a Prazi putty chaser LOL
that is funny..but not as funny as....well...I have one of these..lol
View Image
and the NOT so funny part is when I went to buy it a buncha moons ago at The Tool Warehouse when it was still in existance around here... it was sitting on a shelf next to the Fein Multimaster and I couldn't deciede which one to buy and the salesman said this was just as good and it cost almost $100 less...ughView Image
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
Dear Sir, Over the last couple of weeks I've been working with hot melts on wood, MDF, plastic and glass.Sir, be advised that they work very well no matter what the grain orientation is for wood, and they provide a strong bond when surface or core glueing MDF.Sir, my hopes are that you find this information beneficial and that you have a most pleasant day.
Edited 3/3/2009 5:59 pm ET by Mongo
Sir, my hopes are that you find this information beneficial and that you have a most pleasant day.
Was that a recording...lol?
http://www.cliffordrenovations.com
Why do I keep...http://www.youtube.com/watch?v=n7ZkQC0riwc
http://www.ramdass.org
appearantly he's been outsourced!
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
or automated.
automated ... is that how robot's do it?
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Are you practicing your Nigerian letter writing skills?If so, need to mis-spell more words and make more promises.Otherwise, you have possibilities.;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Sirs, to all of you, I thank you for your concerns. Yes, many economic downturns have been enabled in my areas, howevers, my uncle, being a Prince in my country, has many vast wealths and fortunes. Sadly, he is unawares due to his concerns of mentally health. Should we be providing him with assistance from others, he is able to compensate many of us fairly for your efforts. With many economic sadnesses and misfortunes behind us, should you grant us the gracious moneys to get my uncle mentally prepared he shall reward you more than contemplated in your head.Medical physicians pricing services higher than our reserves request that you assist us. Please send me $23,435.23 which is monthly medical assistance fee. My uncle will then be able to transmission all of his wealths to your banking accounts in your place of residential location.When healthy we shall depart this country with sadness and visit you in your country where you able us to then receive to us the moneys you have been assisting us to transferring with. Much will be remained with you for your lasting efforts. Enough to purchase hot glue gifts for self and friends having cold glue only restrictions.Global kindness my friend who shall soon have wealth with little effort! May your miter joints remain unaccessed to air and tight no openly from near to the eyes.
Ya know? You do that entirely too well to be faking it. How much ya made so far?Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
My only concern with MDF in a bathroom would be if there's not a vent fan, and even then, if the MDF is painted and caulked well, I doubt there'd be much of a problem.
I think the problem a lot of guys have with it is because its not really wood, and it got a bad rep when it first came out with blowing out when nailed. Some of it doesn't have a well defined profile, but the better stuff does.
BTW, I replied to your e-mail
Also keep in mind the runs.....full lengths (16') of MDF are a nightmare to work with.
I typically install crown solo. With poplar, all I need is one of them "3rd hands".
With MDF, you might need a 4th and 5th.
J. D. Reynolds
Home Improvements
I'm also for the poplar. I cannot stand the dust that MDF creates when cut. And trying not to mess up coped ends would be pretty hadr on wide stuff.
Wayne
I'm with Piffin on this one. I really cant stand MDF trim. Its a pain to work with. I use alot of Poplar.
I'll only use MDF for trim if its a budget thing.
Family.....They're always there when they need you.
Seasonal gaps are most likely a result from the house and not the crown.
I think MDF is okay for crown, since it's generally out of reach and not likely to get bumped into. The thing about poplar or any other real wood is that it needs sanded before painting.
~ Ted W ~
Cheap Tools - BuildersTools.net
See my work - TedsCarpentry.com