# Do screw heads really need to be mudded with three coats?



## cibula11 (Jan 6, 2007)

I know that even if one coat looks good and sometimes even two, you can get pak marks, where the screwed area looks like divets all over your ceiling. I haven't notice this quite as bad on my walls, but whoever did my ceilings did a horrible job. If you're texturing the area, any imperfections will be less noticeable, but with drywall, taking that extra day to be "perfect" will really pay off in the end. Unfortunately I know that from experience.

Honestly, I would think 2 would be enough. Sometimes after you prime the drywall, you can see imperfections more clearly....then you could go back and fix anything too obvious.


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## KUIPORNG (Jan 11, 2006)

1. What you described as pak marks, wouldn't it be likely be caused by the fact that the screws was not set properly, i.e. not a little bit beneath the surface of the drywall... rather than how many coats been applied? and if those screws not set properly, besides more coats needed, I believe the area of the mud being applied should also be larger in order to conceal the raised screw heads....

2. Or you mean even the screw heads were set properly (a little bit beneath the surface), if the mud only being applied once, you will see a lot of small 1" x 1" spots all over the walls or ceilings , which cannot be concealed by painting... therefore, need to apply multiple coats to make the 1" x 1" spots become say 3" x 12" mudded area so that you don't feel the spotting effect...

3. none of above


which ways of above best describe the theory?

thanks.


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## AtlanticWBConst. (May 12, 2006)

He's referring to 'dimpling' of the nail or screw heads.

Stick with a minimum of 3 coats. The compound shrinks as it dries. 

3 coats ensures proper coverage that will completely fill in the 'dimple' of the screw head and leave no impression on the wall's surface when completed.

Use very good lighting while you coat your sheetrock. This will allow you to see all blemishes, including any small dents in the sheetrock surfaces.
ALOT more drywall/taping blemishes will show up once you prime the walls (white)...

Tip: When sanding: Use a very bright halogen light placed at a side-ways angle so that the light's beam flows across the surface of the wall/ceiling sideways. This shows up so much more than if you shine it directly from the front. 
Sideways along the surface reveals shadows and even the smallest issues.

(2 coats on the screw heads might look good, until you do this lighting test that I mentioned, then you will realize that you absolutely need that 3rd coat)


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## MinConst (Nov 23, 2004)

This possibly explains why professional finishers will run the mud down the length (top to bottom) of the wall where the screws are.


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## AtlanticWBConst. (May 12, 2006)

MinConst said:


> This possibly explains why professional finishers will run the mud down the length (top to bottom) of the wall where the screws are.


Actually, we do it that way to make the sanding easier. Instead of having to sand down alot of small areas (screws).
By coating it in 'one' long patch....we are able to run the sander up and down in just a few long strokes to get it smooth and right.


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## KenTheHandyMan (Sep 1, 2005)

Not to mention putting it on like that is actually quicker. Taking one long stroke and wiping up one long stroke is way quicker than 'stroke, wipe, stroke, wipe, stroke, wipe'

The halogen light is a necessary tool for this. Listen to Atlantic. A pretty descent looking wall will all of a sudden turn into the craters of the moon once you put a light on it at an angle. And like he said, it just gets worse after the first coat of primer, so it's best to find and fix as much as possible _before_ that.

This is something you're gonna live with for a long time. Take the extra day to get it right.


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## AtlanticWBConst. (May 12, 2006)

Actually, what I was referring to was not the 'thin' line of compound that is used to speedily do the 1st and 2nd coats of screws vertically, but a 3rd coat that is about about the width of the 6" Taping knife (with the edges smooth)

I know that not everyone does the third coat like that, but we picked this up after seeing it done that way on a commercial job years ago. 

Rather than having 3 coats of the narrow line, with several outside 'ridges' to sand down... we coat the 3rd time wider (to cover the 1st two coats)....which creates one smooth surface .... and it sands out much quicker and much smoother.

It's the same concept of how the seams are taped. Each coat is slightly wider than the one before it, to go over the 'outside compound edges'.

If you don't tape it wider with each coat, it builds up, and there is a distinct ridge of compound.


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## KenTheHandyMan (Sep 1, 2005)

That's what I assumed, it's the way I do it. I hate seeing a paint job and you see these little round 'spots'. My walls almost look like several verticle 'butt joints' after my third coat. But once it's painted, it's a consistently smooth surface.

I don't give it quite that much attention if it will be textured.


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## KUIPORNG (Jan 11, 2006)

*How about those screw heads which were not set properly*

I know, in theory, those should be screw down a bit to set perfectly, but you know, practically, there are some of those guys got pass away due to too difficult to screw or just being lazy...etc.. 

say there are 5% of screws not set properly, i.e. they are not 100% underneath the surface of the drywall.... Can we use mudding technique to rectify this situation... I assume the answer is just put in thicker mud and wider coverage... is this the right answer ?

or it is somthing I don't want to hear: "Knock off the existing mud and fix the screw even it means unscrew it and screw a new one..."...


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## yummy mummy (Sep 11, 2006)

*kuiporng*

Hi Kuiporng:

Because soon I will be doing drywall, I am reading all your posts.
How about before mudding the screws, you would go through and hand adjust all the ones that are not perfect?

Is it possible to put in all drywall screws in by hand, so that you can get it just perfect, so the mudding job would be a lot easier?


What is your opinion on that?


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## KenTheHandyMan (Sep 1, 2005)

Actually, if the screw head is not set properly, you have a couple of problems. One, like you say is that it will stick out and get in the way of the knife. This means more mud and in the world of drywall mud, a sixteenth of an inch is quite a bit. More mud means you will likely see a hump. It will only get worse and definately take more time to deal with than just properly setting the screw. If I 'spinnout' and it doesn't sink past the paper, I put another screw 1 inch away and pull the other one.

The second problem is that if the head wasn't pulled tight enough to set into the paper, it might not have pulled the drywall all the way to the stud and you'll have a gap. That means the wall will move back and forth and eventually you get a popped screwhead, popped through the drywall mud that is.


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## KenTheHandyMan (Sep 1, 2005)

Actually, when mudding, I carry a screwdriver in my back pocket and just fix any problems as they arise.


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## KUIPORNG (Jan 11, 2006)

*Actually*

Actually, I do the same, with a hand screwdriver with me when mudding... but... the situation is:

- those not set properly are normally those tiny litle bit due to the fact the screw was not going in at 90 degree... and they are so difficult to screw in by hand... but I guess with a good charge power drill, it should work... I just don't border keep charging those cordless drills as you know power gone faster if it is so forcey...


I am talking about those just very tiny little bit above the surface... not even 1/16 inch I believe... but it border the knife from running smoothly... I am sure you come across those... it can probably be fixed like you said... but I thought it is not a big problem so I didn't fix some of them... I will see if I can revisit them ...


and to answer Yummy Mommy another question, You definitely need a drywall screw gun to get a good screwing job done... in my opinion... hand screwing is too hard... regular screw driver will for sure break many holes ...


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## KenTheHandyMan (Sep 1, 2005)

They have little tips that you can by for use with a regular drywall screw gun. I personally think they sink a bit too deep, but they work better than, for example, a clutch.

An actual drywall/deck driver is the best and gets the job done fast! It makes other drivers look like sssssslllllooooooowwwwwwwwww motion.


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## yummy mummy (Sep 11, 2006)

*kuiporng*

I may be wrong about this, but right now, I still think that screwing them in by hand, (I admit it is a labour intensive process, presently I am screwing in the wood screws by hand, as I can't be bothered to change the drill bit after I have drilled a pilot hole, so I do them all by hand, I have so far put in 500 screws by hand.) but that would give you the best outcome. 

The screw can be directed exactly as you direct it.
Whereas, with a screw gun, there is always some shifting.

(Mind you, I am saying all this because I have not tried doing it yet.
I bet, I may change my mind then.)


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## KUIPORNG (Jan 11, 2006)

*At least use a 18V*

I do some of mine with 18V in the beginning when I haven't got my screw gun... it is still managable... 

but by hand.... I really think it is not doable in this case for the 70 drywalls you are talking about... I doubt anyone here would argue... 

it is already hard enough to hold the drywall in place (even with lift)... "getting the screws into the stud" is the last thing you want to worry about... 

I think even "Terminator" would have hard time to put in 2000 screws by hand consider he does 60 in a day...

if you really don't want to buy another tool... use drywall nails which is the old way of doing it.. which many people still do these days I believe....


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## yummy mummy (Sep 11, 2006)

*kuiporng*

I will have to give it a try.

I guess, you never really know how something is until you've tried it.

Thanks for the information.


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## KUIPORNG (Jan 11, 2006)

*Trying the strips approach but...*

OK, I used advice above (AtlanticWBconst) by trying to mud all screw heads into columns of mud... but when I tried that, I find out only a very thin layer of mud be able to put between screws easily... I don't know if I should make a thicker layer... the layer is so thin that it is almost transparent.... I saw my garage being done that way by the builder, so I doubt if I should make a thicker layer...

please let me know should I make a thicker layer?


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## KenTheHandyMan (Sep 1, 2005)

You may be wiping off too much. It should be 'white' once dry. Try 'floating' the knife more and not pressing so hard. You want it thick enough that you have something to sand! But be careful not to sand it all off. What I see a lot of DIYer's do with mud is glob it on and then sand it all right off. First coat will look thin, then use a wider knife for the second coat. I'm sorry this isn't easy to explain. It's one of those 'show me' kinda things.


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## KUIPORNG (Jan 11, 2006)

Thanks, all I have to say, this mudding jobs seems endless to me... to me... it is harder/longer than hanging the drywall... for drywall, at least once hang, its done, no need to go back.... those kind of things I think a more detail person would like... not me... probably yummy mommy will like this job... but not me...


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## KenTheHandyMan (Sep 1, 2005)

Yeah finishing is much more tedious than hanging.


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## yummy mummy (Sep 11, 2006)

*kuiporng*

You are right. I am looking forward to this job of taping.

Sometimes, I don't mind doing tedious work.

Everyone that I talk to tells me that taping is really difficult to do and make it look good.
But you know, I have to prove them all wrong. :yes:


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## AtlanticWBConst. (May 12, 2006)

Tedious??

Back in the eighties, when we did mostly drywall work, we would do huge condo complexes. 

That meant doing the same identical interior layout for each unit.......

Try doing that unit, after same unit, after same unit.....over and over, and over, and over..... 

....You want to talk about endless taping...UGH.

 


Plus side was: You were forced to get real good and real fast at it....


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## yummy mummy (Sep 11, 2006)

*atlantic*

That is what I plan on doing.

Getting REAL GOOD at it.
Practice makes perfect, as the saying goes.


Boring yes.........


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## KUIPORNG (Jan 11, 2006)

*May be the trick is to use those towels*

I found out that if I use those 14x4 towels instead of straight head, I am able to keep the mud on the wall between screw heads.... l start fall in love with those 14x4 towels... it looks more difficult to use than straight head but I found out they are in fact easier... I for sure go back to do all my outside corner the third layer with this tool rather than 12" straight head....

And this morning, I tried to count how many inside corner, seam I need to finish for second coating.... again... I lost count.... may be tomorrow is better...


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## yummy mummy (Sep 11, 2006)

*kuiporng*

This might sound like a stupid question but what is 4X14 towel?


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## AtlanticWBConst. (May 12, 2006)

yummy mummy said:


> This might sound like a stupid question but what is 4X14 towel?


 
Ha, ha, he means simply a: 14" wide - plastering trowel.

However, we use 12" taping knives, not trowels. Some tapers use trowels, and some use knives....it is always a big debate about which is better....and it always boils down to personal opinions....


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## yummy mummy (Sep 11, 2006)

*atlantic*

I did think it was "trowel", but since I am not totally familiar with drywall tools, I thought there may have been something called a "towel".

I have not tried either yet, but I imagine that the knife would be the easier one?


Thanks for the clarification.


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## KUIPORNG (Jan 11, 2006)

*Don't just tell by the look of the tool*

Yes straight head looks more straight forward... but don't just think it is easier/better by looking.... until you try and compare, you may like the trowel more.... I judge the same way in the begginning and go with straight head most of my muddings.... but then I accidentally find "trowels" can lead to great result with good quality mud... I then now don't want to do without it...


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## yummy mummy (Sep 11, 2006)

*kuiporng*

Thanks kuiporng.

I think I will try both.


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## J187 (May 19, 2006)

You know, I started using those plastic taping knives as a goof a while back and found to my surprise that I actually liked them. I thought they were comfortable and smooth and great especially for small jobs when I'm feeling like just using a small throw-away bucket instead of a mudbox and tossing everything afterwards. Still have an assortment of good ole fashion metal taping knives, but I dont' hesitate to reach for the plastic ones at all. They have good flex to them too if that helps some people. Careful though if you do use them, the DO have a one tapered edge which is hard to notice at first.


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## KUIPORNG (Jan 11, 2006)

*Disposable is a good idea for mudding stuff*

I definitely agree the idea of throw away stuff to avoid cleaning as it is such a pain to clean... but dispose the bucket is kind of expensive though...for mudding knife, on the other hand, isn't really need to clean if you don't care about the handle... the knife itself can be clean easily by using two knifes scatching each other and I found that quite entertaining, like a Japanese chief doing in those resturarant with those pan fire beef..or like Jackie Chan playing KangFu... etc... as long as cleaning does not require water.... it is ok...

for mixing setting type compound... definitely use disposable container... I like to mix small amount at a time with those plastic food container from supermarket... using any sticks/screw drivers etc... rather than mixing with mixer with big bucket.... then you don't need to clean the mixer and the bucket....setting compound is a real pain to clean.... 


I think those business minded people out there should invent more disposable tools for mudding then they can make some money... I wonder why there isn't those liner which we can put on regular bucket to house the muds and dispose after use being invented... I would the first person to buy them if there are such....


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## drywalldave (Sep 17, 2011)

*Yes 100% 3 coats*

This answer is going to end with another question that poses perhaps even more expertise.

Yes you need 3 coats, however; there are many dependant variables.

1. the kinda of mud you use
2. drying time
3. how far they have been counter sunk
(probably more factors as well)

To answer why 3 coats, as well the technique used for 3 coats is also important.

First coat ( this is the part going to my question )
Using 'taping mud' to fill for first coat./ "ALWAYS CRACKS AND SHRINKS"

Second (tape mud again or topping finishing mud) coat a must because first coat crack shrinks. This looks almost perfect. However;

Third coat needed for a true perfect look.

TECHNIQUE : now when you put your mud in to fill nail holes, you do not EVER leave excess mud on the board. You always "scrape clean at a 90 angle with your knife" If you don't do this, you will have sanding hell. 

Myth: some think they can simply put lots of mud to 1 coat nails. Well good luck with that it's NEVER worth the amount of sanding, vs 3 coating scrape clean.

Two Coat Possibilities: *I have experimented a lot, 2 coat is doable"

You must first coat with a hot mud, quick dry, this also enables you to go back and do 2nd coat REALLY FAST because hot mud dries and cures even faster in small amounts. ie; the screw head fill is tiny, and hot mud will cure, and completely turn white enabling you to coat it second time with NORMAL mud, either tape mud or topping mud. I wouldn't use all purpose or filling mud at this point. Finishing mud only over top of the Hot mud and only after the hot mud is white in the screw heads.

IT IS ESSENTIAL IF YOU TRY HOT MUD YOUR SCREWS THAT YOU SCRAPE CLEAN!!!

SCRAPE CLEAN!!! if you don't,  sanding...... input screams here. if you don't know what I mean by scrape clean, please don't use hot mud as it will cause you a nightmare.

Opinion on two coating:

Even though I have done it, tried it, really tried, "to save time" i still found a 10% failure rate in the fills. (means I had to still go back and touch up a few screws after prime)
So even if I hot fill my screws, I'll still go back and hit them 2 more times with either taping mud or topping / filling compound. always using finishing/topping compound last over nails, and always scraping clean for all coats gives a 100% perfect NONE NOTICEABLE screw head all the time.. rather 99% till you fix them before final paint.

FISHING THE SCREW HEADS:

Very VERY light sand... ah.. wasn't that easy! 

[[ i will come edit this more, i read it see I missed a few things, and would like this to be a complete answer]]


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