*
Ok this may seem basic but remember I’m mostly self taught. anyway occasionaly when I’m taping drywall the tape will bubble in a spot or two. sometimes I catch it when I’m applying it and can work it out. but every so often when I go to put the second coat on it’s bubbled and there seems to be no way to set it back other than to cut it out and redo it. now this happens maybe on one foot in a hundred so please someone tell me what the hell I’m doing wrong or is this just a common nuisance that must be lived with. I put the mud on pretty liberally for the tape coat so I can’t figure out why it ain’t sticking. (BTW I’m talking about paper tape obviously not mesh) I don’t seem to have this problem with inside corner but rather with flat joints and it doesn’t matter whether it’s a factory edge or a butt joint.
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Are you thinning down your bed coat a little, or useing it straight out if the bucket or box?
Your bubbles are dry spots, where the tape is not bedding in the mud behind it. It generaly occurs when the mud is to stiff and not enough pressure is used when beddin the tape in it.
Cutting out the bad spot is about the best solution. I have tried lifting the tape and pushing mmmmud behind it, and it works also, but if you are not carefull you get a bump and/or grit behind the tape. I mostly just cut them out now, if I get one.
*Straight out of the bucket. that's what I figured too Dave. One job I got to experimenting a little and actually wet the tape first. that really worked great but it's a time bandit. I gues not as much of a bandit though as having to cut and redo, especially if the clients sees it and asks "what's that?"
*Add water to the bucket, to make the mud workable. And yes soaking the tape works very well. Who the heck was it that used to advocate adding dish soap to the mud? I believe it was either Clarke or Buck.
*That'd be me! Still works better for me than water......does the same......thins a bit.....actually makes creamy would explain better.....and doesn't bump up the set time as when I've thinned with a bit of water. Lately....I've been finding better results with mixing dry from the bag. Torn between the bag and premix now! Also.....too much bedding mud can cause a lift. I use just enough to glue it down......not so much that you can't find the tape in the mud...on the first coat. We just had a job where one wall patched in had to be cut out and re-taped......seemed that bucket musta gone bad....because a different bucket was used in that area.....and the same guy did all the other patches...and that was the only part that bubbled bad......and it bibbled real bad. I know he filled the voids behind...but it dried to the point it didn't look like anything was back there. To be safe....we cut it all out...still mushy after 48 hrs....and filled with 20 min durabond......then durabonded each coat...for a harder finish. Worked well after the initial fix. Jeff
*Jeff, I started useing your soap trick on patches in painted walls. I use to get what looked like acne pimples where I feathered the mud over the painted surface. When sanded,you could not always see the small craters, because they were full of dw dust. The primer would bring them out, and then it was back to skim coating the area agian. The dishwashing liquid added to the mud solved the problem.I always thin my mud with a little water, using a 1/2" drill and a mixing paddle. If I am doing a large job, I'll mix a whole box or 5 gal bucket. If it is a small job, I use a big "tatter masher" and only mix the top 3-4" of a bucket for the tape coat stage. I think I'll try the soap mix on some new work for the tape coat. If it works as you have advertised, life will just get a little better.Hey, anybody want a wet tape banjo. I bought one about 25 years ago, used it on a couple of jobs and hung it up in the shop. To messy for me, and the clean up was a pain in the arse. Maybe put it on e-bay? Would be a hoot to see if anyone wanted to know what kind of insturment it is.
*do you guys find that smoothset works better with dry vs. premix? jeff... want to run the experiment?brian
*The correct consistency for mud when taping is "pancake batter" thick. It should be applied APPROXIMATELY 1/8" thick.I have a question about using dish washing liquid in the mud. Have you ever had to paint the drywall after you do this? Has the paint held up?The reason I ask is because dishwashing liquid dissolves wet latex paint. This is one reason why the paint brush manufacturers recommend cleaning your brush with warm, SOAPY water. Preferably dishwashing soap. Just curious... I have wanted to experiment and see for myself, but have just not had the time.James DuHamel
*James,The active ingrediant in most dish washing liguid is glycerin and wetting agents, along with a thicksotropic agent and perfume. Glycerin is just a high molecular weight alcohol. Most of the water base paints also contain butyl cellesolve, another alcohol, solvent. For a clean up, they work together because the butyl cell and glycerin are soluable in each other, and also in water.I would not think that the amount of glycerin in a couple of capfills of dish washing liquid ia a five gallon bucket of joint compound woul be enough to cause any problems. The solvent in the paint might well resolubilize the glycerin, but since it is compatable with what is paint, it should not affect it.I am pulling this all from long term memory as a lab tech in a paint product develoment lab 30 years ago, so I could be dated as related to newre products.Dave
*Would it then be safe to say that a capful from a bottle of glycerin, sans the additives in regular soap, would give the same results? BTW, anybody know just what the ingredients in a bucket of mud really are? Perhaps there already is a capful of glycerin.
*After thinkingsome more on this, I think need to add that the glycerin and solvents in the soap would be suspect if something funny did happen with the paint. However as I mentioned above I don't think it will happen.I believe what makes the soap trick work with the drywall compoud is the addition of wetting agent in the soap. It works somewhat like the addmixes for concrete. It just makes the water in the mud wetter and thus slicker, but doesn't change the properties at all.Just a hunch. Anyone ever get an Material Safety Data Sheet with a bucket of mud? Dave
*Dave......I just found a down side to the dish liquid soap you'll want to look out for. Last time I bought a bucket o'mud...the only thing on the shelf was the lightweight stuff.....which I've used in the past.....but this time I wanted it nice and creamy....so in went in the soap.....and that I fought with that stuff.....to get rid of those little bubbles....the whole day! I'm thinking when they whip it up to make it light weight.....that air...plus the bubbles from the soap.....get together and multiply! I use a banjo once.....looked like a good idea....maybe in the right hands! Jeff
*Ralph.....a mud rep visiting our trade school way back when was the dude that gave me the idea. He said the mud already has some soap in it.....that's why it works well. We really should sent a sample to the lab.....who's our lab guy this week? ...remember...if it floats...it must be a duck! A witch...A witch!....OK....it might have been a drywall rep dude....either way...they brought donuts. Jeff
*Uhhh yeah....maybe once...in the past 20 years.....a small bit of drywall I taped may have been painted......accidentially.......Jeff
*MATERIAL SAFETY DATA SHEET USG Brand All Purpose Joint CompoundMATERIAL ........MATERIAL WT% Limestone >50 Water <35 Mica <10 Attapulgite <5 Expanded Perlite <5 Vinyl Acetate Polymer <5 Vinyl Acetate Monomer <0.1 Acetaldehyde <0.1 Crystalline Silica <2 Lightweight All Purpose Joint Compound Plus 3 Ready-MixedINGREDIENTS....MATERIAL WT% Limestone >35 Or Dolomite Or Gypsum Water >40Expanded Perlite <10 Ethylene-Vinyl Acetate Polymer <10 Or Vinyl Acetate PolymerAttapulgite <5 Vinyl Acetate Monomer <0.1 Acetaldehyde <0.1 Crystalline Silica <2
*i think i'll run an experiment using water, dish soap, glycerin, and floetrol (however it's spelled). not really expecting any problems with primer adhesion, though. will basically show the best admix.brian
*That sounds like something I would do. Hey - I LIKE this giy!!!!James DuHamel
*Dave,Thanks for the info. I just learned a lot!I have just been a little uneasy about trying it, but I think I may do that soon.James DuHamel
*I used to tape a lot with my bazooka. Putting dish soap will make joint compound slicker,making it easier to run through tools. Light weight mud doesnt need it. In the old days before plus three, we did the whole job with joint compound. Thats when a little soap was good to apply those slick coats.Now the original question. Dry spacing is from 1 missing mud , not filling cracks when hand taping .2 dry mud ;always mix mud as thin as you can handle it. This is my rule of thumb for thinning;get a clean five gallon bucket of water. Dip your mud pan in the water and bring it out touching both sides of the bucket=one dipper. Hand taping for me means ;3 dippers,after you have done the prefills.[bad places ,like around a tub for example]Where I like soap is in texture, whether popcorn as yall call it , or wipe down. It makes the spraying go quicker and wipes down very nice. Never use light weight mud for wipe down.
*What is "wipe down"?Is that the same as Stomp and Drag?I use lightweight for the final coat, and for the finish texture coat. Never had a problem. I use standard mud for taping and fill coats. Smooth walls are not common here. Textured walls are the norm. James DuHamel
*Barry E.Good post! You would think that after attending night school for 7 years pursueing a degree in chemistry I would be more interesred in the "stuff" in the products I use. Honestly, though, untill the soap/paint question came up, I never had a thought about what is in joint compound.One little "tid bit" that shows up in the list of ingrediants is the Vinyl Acetate Polymer. If it is written another way: Poly Vinyl Acetate (PVA), many more of us would recognize it as white glue (Elmers' type). The acetaldhyde is what we use to call a "stabilizer", to keep the product from going bad on the shelf. After you open a bucket of mud, ever notice how it can sour if it is not used up in a few months? That is because the stabilizer has evaporated. Some manufacturers put plastic sheets on top of the coumpound in the bucket to futher slow this process down, and keep air from drying out the top of the mud.Brian, great idea! Floetrol is 100% acrylic, so it might make mud "slicker than snot on a door knob."Let us know what you expriment turns up.Dave
*Wipe down ,knock down ,spanish texture is all the same to me.= spraying mud on dry wall and troweling it flat with a knife after the water leaves the top of the mud.Light weight mud is to soft of a finish for wall texture. Scuffs easily.A better and cheaper option is joint compound ,and some of us have wall spray texture at our disposal,which comes dry in a 25 pound bag. there is a lot more glue in joint compound also. I used flotrol on a job that had to be very slick. I usually like to cheat a little on slick and roll the job with block filler , or joint sompund mixed with paint and water,to give a very small texture. With a chance the custumer will put semi gloss it needs the light coat as a"bridge over" effect that will hide the nail rows and the joints being slick and the rock being a little rougher.Floetrol works well , but it is very expensive considering how much mud is put on in a days time. For quality its the deal.Vinegar is good to keep mud or paint from souring. It will last a long time . In the Wall and Angle trade mag they recomend vinagar in the mud for a faster dry time. I dont like smelling it that well.
*Good info here guys. Recently after listening to the Lafarge sales reps pitch I tried some of there redimix. one thing I noticed is that this stuff comes straight from the factory preloaded with lots of bubbles. it's a pain to work 'em out. I'll probably go back to USG's product. one other thing I want to ask is about clean up. most of my jobs are small and I only use 1/3 to a little over half a bucket of mud. being a cheapskate I use the bucket until it's gone on later jobs. I have often thought about using setting type but that would involve going outside (and in jan/feb that's F'n COLD!)getting a bucket of ice water to mix with and then to clean up a bucket and mixer with to boot. it's bad enough having to go outside and use a hose or spigot to clean my tools with ice water after I'm done without that added hassle. any thoughts or suggestions from anyone?
*I forgot about the Elmers Glue! Was told that was kinda in there too. Jeff
*That may be the bubbling problem. Mud goes bad. And get contaminated with boogers....if left sitting around. Unless you are gonna use the rest of the bucket in the next few days......do yourself and you customers a favor....and dump it and buy fresh when needed. Really.....how much is that half bucket worth? $5.00? When given the chance....hot water from the laundry tub.....or regular tub....makes mixing the joint compound.....or mortar....or grout.....easier to live with on a cold damp day. Never use compound that's been frozen......never the same after that. It may work for a while....but it'll bite ya sooner than later. Jeff
*if you use that little the dry may be the way to go or you could buy the premix by the box ( slightly smaller quanity and cheaper because no bucket)
*good input guys thanks again. I'm gonna try using the dry stuff on the next job and see how it goes. question with that, if you're using a mixing paddle do you wait until you're ready to mix the next batch before you clean the hardened suff off of it or do you stop and clean it while the stuff is still fresh right after mixing it? I could see that being an issue with setting compounds as opposed to drying compounds.
*Learn how to scrape down the sides of your bucket as you use the mud, then the little dry boogers that you sloppy guys drop into your mud are never there.Also, if you have a half bucket of mud left over and hate to waste anything, you can pour a cup of water on the surface of the remaining mud and pour it off later when you want to use the mud.Steve, I usually find it's better to clean up as you go. It's an easier, faster job. Have an extra bucket of water handy, run your paddle full blast to get the majority off aand then a quick squirt with the high pressure hose and you're clean and ready for next time. Think about tossing that nasty paddle into the truck and getting mud on and into other things that would have to be cleaned off when you found out what you did.
*steve. you could also have a 5 gal bucket with water around to drop your tools into while your doing other things. no need to clean up 3-4 times a day.brian
*Way to go Ralph. I keep my bucket side clean every time I load my pan. Keep a bucket of water and a fender brush handy, and never clean the last part of the pan back into the bucket. Buy a roll of plastic wrap (like you put your sandwich in)and place a layer of it over the remaining mud before you add the water. Pour the water off next time you use it and pull the plastic wrap. I have kept compound that way for several months.I use quick setting compounds a lot for small jobs. Ussually mixed in a large coffe can and toss the can at the end of the day. That way the only thing I clean are my tools. Of course I drink a lot of coffee. You young soda pop guys are SOL.
*Theoretically, soap should cause adhesion problems for paint. Floetrol should not.2 cents.
*Talking about boogers- If you get mud by the box, dump it into a clean bucket as soon as you open it, and mix it up, add some water esp. if it's all-porpoise. One of my pet peeves is with others who work out of a box of mud and then close up the bag. Next day its useless for anything (except maybe bedding tape) so just toss it. -Ken
*i Glycerin is just a high molecular weight alcohol.So, a tube of K-Y is really just a bottle of Jack-Daniels in disguise ?
*I use mud by the box. I do indeed empty the contents into another air tight, sealable container before I do anything. The container I use is square. This works well because all of my taping tools are squared off. It allows me to srape the sides as I go, keeping them clean and free of dried on mud. When I get "boogers" in drywall mud, I call it a contaminated batch. I toss ALL contaminated batches. I really hate running my knife across a blob of mud, only to find out a hard chunk of mud has caused a streak. Gotta go back, find the booger, get it out, and smooth out the mud again. James DuHamel
*Luka,I think Jack in the Black falls some where else in the hiarchy of alcohol. On the low end is methanol (wood alcohol), drink it and at the very least you go blind (not that kind of blind). At the high end you have the glycols and glycerins, not really drinkable because they are pretty close to solids at normal temperature. If you survived consumption of them, you would have the worse case of the "Hershey squirts' of your life. :)
*yuck
*thanks guys. I'll be finishing off a drywall returned doorway tomorrow so I'm gonna try some of the suggestions out.
*well steve, it's just been done now.started the mud admix experiment today on a couple repairs, using only 2 capfulls of floetrol to bucket of mud (USG all-purpose)...on the initial pass, numerous very, very tiny bubbles. worked out easily. material easy to work with. finished well. will sand and apply second coat tomorrow.got the impression would be best way to create texture coat material from compound...brian
*Did the bubbles appear on a painted wall?
*I always just add some water to the pre made buckets of mud. You can make it as fluffy as you like. I haven't had any problems with bubbles either. Is there anything wrong with this? Usually I only use the pre-made stuff to put the tape on and then mix from a bag of forty five for the top coats. It goes a lot faster not having to wait for the darn mud to dry. Peace,Casey
*Casey- Your approach is interesting to me. I've always done the opposite- Hot mud for taping and fill-ins, and pre-mixed for the rest. Does the hot mud give you smooth enuf for a fin. coat? Or do you always texture so it doesn't matter? -Ken
*Noooo, I hate texture. As long as you are diligent about cleaning out your bucket and tools, using fresh water (not water that has gotten a ton of dust and debris in it), and mixing with a paddle and drill. For my final coat I just make sure to mix it up very thin. I do mostly smaller jobs like kitchens and baths, so the down time waiting for mud to dry is too much. If I were mudding a larger area, I might use the pre-mix, but I've seen that stuff still too soft after a full day. I live in St. Louis, where it is usually quite humid, slowing down dry time. I imagine in dryer climates the drying time speeds up significantly. I'm just guessing though. That is just the way I learned, I don't know that there is a right way in this case.Peace,Casey
*casey. i'm just posting results from an ongoing experiment i said that i would perform (see earlier discussion in this thread).okay... usg all purpose + floetrol -i now believe that the tiny bubbles were an artifact of the particular repair i was making - repair on textured wall. the air must have come from the spaces between the texture bumps; hence, the bubbles appeared. this was a second mudcoat on a repair started by a partner of mine, and not a particularly decent job that he did. anyway ...easiest finish job i've done. required so little sanding that it probably wasn't necessary. texture coated today. no need for a third mudcoat. will prime and paint tomorrow.i'm definitely keeping some floetrol around.next run will be with dishsoap.brian
*Brian,Where do you get floetrol?
*home depot. any paint store.it's a latex paint conditioner, generally used to improve flow through sprayers and reduce wear on sprayer equipment parts (o-rings and washers).brian
*ahhh I see. thanks. (can you tell I've never sprayed anything)
*steve. i don't want to leave you with the impression that it's only for equipment spraying. if you decide to try adding to the mud, you can use the remainder to condition your water-based paint for rolling or brushing. results are superior to untreated paint. "penetrol" is the equivalent product for oil-based paints.brian
*other possible experiments using floetrol/penetrol would include addition of small amounts to plaster, window glazing, mortars & grouts & floor leveling materials (though there are already latex additives with superior strengthening properties for these, with the downside of shortened working time), plumber's putty (penetrol may extend the life of the seal), ...brian
*I find that flotrol is most useful in brushing. [cutting in ] I do a lot of painting and it will pay for it self in the time saved making you quicker.Example; Cutting in the side of a door can be done in one stroke if there is enough flotrol in your paint. I never use it for rolling. [Im too cheap]happy mud and paint trails ,Tim
*My solution was to simply cut a 1/2" line in the bubble, inject some watered-down mud then press down. This is the same trick I use with wallpaper. I just moved a wall in the house I built (and that's another bit of advice: Do the framing BEFORE the sheetrock guys come in) and even for a DIY it turned out pretty good.
*So if adding this stuff is great for making your mud nice and smooth, is there something you can add to the pre-mix to make it set up faster? This would allow one to sand sooner without having to mix from a bag of forty five minute, or whatever. That way you get the best of both worlds.CaseyP.S. Can you add floetrol to your mix when using bags of forty five? Anyone tried this, or is there some reason that it won't work?
*Jeeze, Brian! Are you keeping some in the night table drawer? :)
*Well I tried my first application with setting compound. took a little to get the right consistency but went on pretty well after that. I can see I'll need a little more practice with this stuff but it is nice to have it set up this fast.
*Casey- Faster? Yeah, use 20-minute! Or Fixall which I think is like 10-15 mins..........As far as sanding goes, you still have to wait well past the time it takes for hot mud to just set up- the water in the material still needs time to evaporate. Sanding before then is a pain and clogs up your screen, etc. With heat and a fan, I can usually sand in 4-6 hours.......For finish coats I just don't beleive there's a way to go any faster. JMHO Cheers- Ken
*adding "smoothset" will decrease dry time (available at home depot). i believe that this is what ken is referring to. various dry time mixes available (ie. smoothset 20, smoothset 40, ... no reason why floetrol wouldn't work under any circumstance where the product is water-based.dave. i only used two capfulls for the mud. i still have 1 quart minus two caps to play with... |:-)>| ps i'll warn you guys. 4 capfulls in 2/3 bucket rendered the mud uselessly thin.couldn't get around to the mud + detergent. i'll keep everyone posted. results due tuesday.be sure to let us know how the floetrol addition works for you. i loves it :-)have a great weekend,brian
*for mixing w/soap.....I'll crack a new bucket...and cover the top with about 1/4" thick layer of soap. Mix about 2/3rd way down. Use about 1/2 bucket....and cover the top with about 1/8th" layer of soap again.....mix to the bottom. Seems to be the mix for me. Report back.......Jeff
*Thanks Jeff,Since I first heard of the soap trick on this sight, I never measured how much it took. I have just been pouring and mixing untill it feels right.
*that's just the amount in got in the habit of using.....there may be a better mix. Maybe more.....maybe less......haven't really experimented with it......just tried that first...it seemed to work....and I stuck with it. Jeff