Ok, in the process of doing the trim work on a small renovation project at home. I’m using 8″ high mdf base board. Its actually quite a nice profile.
I’m attaching it to the walls using my Bostich 15g finish gun with 2″ nails. The problem I’m having is that it doesn’t appear to be “tight” to the wall. By this I mean, I’m hitting the studs with the nails, but it seems to be “pulling” back off the wall after I take my hand off it.
Not a tremendous amount but enough that the ocd is noticing it each time I look at it. I’m planning on running a bead of caulk along the top in the spots where it is firm against the wall.
However, is this normal with MDF? I also plan on hanging crown molding and I’m not sure if MDF is the route to go.
Any suggestions?
Thanks
Barney<!—-> <!—-><!—->
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Its not the destination, but the integrity of the journey.<!—-> <!—->
Replies
You need to push the work tight when you nail. MDF isn't very strong, the nail doesn't pull since it will colapse the material. The immediate force of a gun nail won't pull much in anything.
Beat it to fit / Paint it to match
I did see a couple of spots were there was "blow-out" on the back after I took the piece back off the wall. Not much, but enough to warrant looking for advice.
Of course it doesn't help that this is a 90 year old house.
Thanks
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
I have had a similar issue. I found that I was setting the nail too deep. If too deep the nail pulled the back of the trim out, leaving it proud of the wall. So I turned down the pressure and reset the gun. I had to reset about every 10th nail but it held tight.
"It is what it is."
I'll have to go back and check the pressure on the tank. My son might have "tweaked" it when I wasn't looking.
He's getting to an age where he likes to pick up everything.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
I have installed quite a bit of MDF. The 15 guage is probably bigger than you need, because it doesnt take much to hold MDF in place. I use 16 guage primarily & some 18 guage. The 16 & 18 nails are actually square in section, with kind of a chisel pointe tip, that dont have as much tendency to blow out the back. They also leave a smaller hole to fill, as they dont have as much problem with "mushrooming"
I recently installed 6" poplar baseboards in my basement and although I was really careful when framing, there were a few spots with gaps larger than caulk would have cover without being obvious--I pre-drilled with a countersink bit and then screwed the baseboard to the nearest stud and it sucked it right in--much easier to fill the screw hole with some wood filler than try to caulk the gap.
That's the other issue I have in some spots. The space b/t the wall and the baseboard in some of the spaces is 3/8 ". I'm concerned that the MDF might not hold up to a screw without blowing out. I'll have to take a look and see if that's possible. I can deal with caulk along the top in some spots if the gap isn't too big.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
Barney,
Perhaps you should be glueing it.
With thin mouldings, I usually run a line of yellow glue across the top because there isn't much material under the nail head.
If your moulding stands off the wall, a prop nailed to the floor can hold it against the wall until the glue grabs.
Ron
I had actually thought of using the glue, but wasn't sure how to "hold" it to the wall until it set up. The nails are a great idea. Thank you. I've got a few more feet of it. Perhaps I'll try that.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
3/8 " is an awfull big gap, are your walls that wavy or could you maybe have some overlooked drywall lumps back there? If they ARE that wavy, then that base is going to look bad if you make it follow the wall line. You might have to compromise between pulling the base in part of that gap and caulking the remainder.
There are only a couple of spots, 2 actually, that are about that big. The walls are actually that wavy. Didn't really see if when the dry wall was being hung. It wasn't until the baseboard was against the wall did I see it. By that time it was too late to correct. I'm going to try and pull it in and split the difference with the caulk.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
"The space b/t the wall and the baseboard in some of the spaces is 3/8 "..."Since you are using a nice profile 6" baseboard, I assume that you want the room to look nice when you are done. Sucking the baseboard into a wavy wall results in a very obvious wavy line along the top and bottom edges of the baseboard, especially when viewed from an oblique angle.Caulking a 3/8" gap looks a little better than sucking the base in tight to a bad wall, since only the top edge looks wavy, but I would not like it.The best solution is to float out the wall in those bad areas with drywall mud so your baseboard line will look good. You can feather out the floated area 18" to 24" and people won't notice. If the wall is textured, use a damp sponge after the mud dries to feather out the boundaries of the float where high spots of texture prevented your drywall knife from feathering cleanly, then spray the area with Homax aerosol texturing compound, overlapping beyond the new/old boundary.It's more work now, but the result will be worth it.By the way, I use 18ga on baseboard.
BruceT
Thank you so much for all the advice. I really appreciate it. I'm a little concerned with caulking that large of a space. I know that the way I am, it will drive me nuts every time I look at it.The good thing, if I can find it, are that these spaces tend to be in the corners. A little easier to make the corrections and hide.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
re.: your OCD...I feel for you man.
I too would use drywall compound to even out the wall as much as possible. But that means repainting the wall and it's probably too late for that.
Also, I would not have used MDF for baseboards or door casings since it won't hold up to too much abuse. Instead, I would have used a three piece baseboard made up of a 1x5, a base cap, and a quarter round. The 1x5 would be fairly straight, the base cap would be tight against the wall, and the quarter round would be tight against the floor. This makes for a much nicer trim installation were the walls and floors are not straight.
But, if you are stuck using MDF, screwing it were you have problems is your best option. You could also try using staples instead of nails.
MDF for the crown is a good, low cost choice. I use adhesive and nails.
I second the opinion for using a two-piece baseboard. I just finished redoing my parlor and there were a couple of walls that were pretty wavy. I used 1x6 clear pine for the base and let it float over the waves. Then I nailed on a cap trim that I was able to get to bend tight to the wall. Glued and 18ga brads to hold it. Since there is a bit of reveal at the top of the 1x6, you really can't see the waviness any more.
Did the same thing with my crown molding, using a large (thick) cove-type crown that wouldn't bend around some of the worst of the waviness, but the identical cap trim profile (nailed to the ceiling) was able to conceal everything. Worked great and installed real fast.
MDF is not much more than thick paper, so don't expect too much from it. Nail holding is not it's strong point. I'll double nail if holding ability is a concern--putting two nails close together instead of one is no harder to hide than a single hole.
As for MDF crown, that's a better use for the stuff than base since there is no danger of day-to-day wear and tear.
Beer was created so carpenters wouldn't rule the world.
The MDF definitely has both advantages and disadvantages. The 16' "boards" were convenient. When you have used it, what have you set your compressor at?
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
When you have used it, what have you set your compressor at?
I don't change the pressure going into the airhose, but rather adjust the depth setting on the gun.
Beer was created so carpenters wouldn't rule the world.
Thanks. I'll have to play with the depth setting on the gun.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
for mdf baseboards and other mdf trim (except crown where adhesive can get a little messy during the positioning), I'll usually put a dollop of pl adhesive every foot or so... sometimes more if I think its needed, then shot it in with brads. since it's glued, I really don't worry too much about hitting the studs, which buys me back the time I spent glueing it, and the brads don't mushroom as bad as the bigger nails. if theres a spot where it's trying to pull away from the wall during install, I'd probably try to shot a couple of brads in close together at opposing angles... that ususally holds it.
was able to get the trim to pull in a little tighter. Now its caulkable to split the difference.Not sure if I'll use the mdf again. Like you said, too many mushroom nail heads.
Barney<!----><!----><!---->
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Its not the destination, but the integrity of the journey.<!----><!---->
Barney,
I installed 7-1/4 inch x 3/4 inch S4S FJ-cedar (paint grade), doug fir, and solid cherry. I found that a lot of the walls were bowed or concave. In the end, I had to have the dry wallers come back in and float out some of the walls. It was a real pain since it had to be repainted after being refloated, but it does give it that precision look. If you have cared enough to select nice tall base board, then I think it'll probably be important to you as well.
Also, for many areas, I shot two brads in a V pattern to really hold the base board tight into the wall.