Finish question

[Foxfold]

The pieces I do are usually glued onto a backer board, as with this Tiger.  I use ¼" plywood for both my cutting and backer.  Now I have a  question.

I use Danish Oil on my cut pieces before I glue them onto the backer. Up to now I've only applied the Oil to the front of them as Tony says that if I dip them it may make a difference when gluing them later. I don't mind doing this but getting oil into all the twiddly bits with a small brush is very time consuming.  What do you all do ?  Do you come across a problem when gluing ?

[loftyhermes]

I dip mine in Danish Oil, then glue to the backer after the oil has dried, never had a problem with the backer coming off, (that I've heard of).

[Rockytime]

I dip in 50/50 BLO. When dry no problem gluing.

[OCtoolguy]

Let me get this right. The baskets that I have been making, I glue them first and then oil them and try to wipe as much off as possible. I thought that the oil would prevent the glue from holding. If I am reading this right, it would be great to be able to oil first prior to assembling.

[Bill WIlson]

The rule of thumb is that for PVA woodworking glues, the bond is optimized with bare, freshly milled surfaces.  That doesn't mean that anything less is necessarily doomed to failure, just that the risk is greater.  Also, be aware that a successful glue joint between finished surfaces once isn't a guarantee that it will always work.  In general, scrolled projects don't have the same strength requirements that furniture or cabinet making does, so we may be able to get away with some things that you would never try with other woodworking projects.  You have to decide if the risk is worth it or not. 

[bcdennis]

I dip mine as well and never had a glue issue.

 

[Roberta Moreton]

I dip my fretwork first. Baskets and such, I glue first. 

[OCtoolguy]

Well, I guess I will give it a try. It would be great to be able to apply the Watco's to all 9 layers prior to glue up.

 

[Bill WIlson]

14 hours ago, octoolguy said:

Well, I guess I will give it a try. It would be great to be able to apply the Watco's to all 9 layers prior to glue up.

 

Test on some scrap pieces first.

[Goat]

kinda on topic, do you guys know how long shellac takes at actually dry/harden?  had to redo a few pieces today that left paper towel design impression in the finish as I had to weigh it down when gluing.  I sure hope it will be dry by Saturday as that is when I must deliver the pieces.

[JTTHECLOCKMAN]

1 hour ago, Goat said:

kinda on topic, do you guys know how long shellac takes at actually dry/harden?  had to redo a few pieces today that left paper towel design impression in the finish as I had to weigh it down when gluing.  I sure hope it will be dry by Saturday as that is when I must deliver the pieces.

Shellac takes about 30 minutes to dry. It is usually as an undercoating to a top layer. 

[JTTHECLOCKMAN]

I glue all my pieces first and then dip as a unit. Now if I paint a backer board then I switch to an epoxy for gluing. 

[Goat]

18 minutes ago, JTTHECLOCKMAN said:

Shellac takes about 30 minutes to dry. It is usually as an undercoating to a top layer. 

Its been like 15 hours.  I placed a paper towel over the piece and then a heavy box (like 5 pounds).  It left the pattern of the paper towel in the shellac finish.  It has 3 coats with at least 12 hours between coats.

 

I know it dries to the touch fast, but I don't think its "usable" for a lot longer, what that time is what I'd like to find out.

[JTTHECLOCKMAN]

36 minutes ago, Goat said:

Its been like 15 hours.  I placed a paper towel over the piece and then a heavy box (like 5 pounds).  It left the pattern of the paper towel in the shellac finish.  It has 3 coats with at least 12 hours between coats.

 

I know it dries to the touch fast, but I don't think its "usable" for a lot longer, what that time is what I'd like to find out.

It is not shellac then you are using. Shellac takes little time to dry and is ready to top coat in 30 minutes. Can you show us the can and is it a spray or wipe on or brush?? Something does not sound right. Is this flake shellac and you are mixing the formula and if so what are you using and how old is it??

If you are talking spray shellac already premixed it is the same as lacquer. 3 to 4 hours for full cure in reasonable temps. 

Edited June 20, 2019 by JTTHECLOCKMAN

[Goat]

1 hour ago, JTTHECLOCKMAN said:

It is not shellac then you are using. Shellac takes little time to dry and is ready to top coat in 30 minutes. Can you show us the can and is it a spray or wipe on or brush?? Something does not sound right. Is this flake shellac and you are mixing the formula and if so what are you using and how old is it??

If you are talking spray shellac already premixed it is the same as lacquer. 3 to 4 hours for full cure in reasonable temps. 

Its definitely the right stuff.  12oz can of Clear Shellac Spray from Home depot.  Honestly this stuff still feels a bit tacky at 12 hours.  I put a coat on like 10 PM last night, left it outside to dry all night (covered porch) and 10 AM it was still pretty tacky.  I waited another 7 hours or so before using the paper towel, so I guess it was even longer than the 15 hours I estimated.

 

I also got a can of the brush on, but it seems to take just as long, just doesn't stink as much.

 

I've had this issue before, but thought it was due to me putting on too many coats too quick since it was winter and I was waiting like 5-10 minutes between coats.

Edited June 20, 2019 by Goat

[JTTHECLOCKMAN]

https://www.homedepot.com/p/Zinsser-12-oz-Clear-Shellac-Spray-408/100176744

If this is the stuff you are using I am at a loss. I use this all the time and never had a problem. It dries to the touch in about 10 minutes. You spray a light coat on and if need more again light coats. You say you left it outside. Is it humid or moisture in the air. Any moisture or dew in the air is not good for any finish. The smell is not bad at all. I spray in my basement shop and never smell it in a couple minutes it is gone. Did you shake the can?/  What is underneath this finish??  Did you oil the project before using the shellac. ??? Something is not right here. I suggest you spray a seperate piece of wood and see what the results are. Do nothing to the wood. Just spray it. If that does not dry either than you have a bad can of spray. That stuff has a shelf life of about 1/2 year if stored in cool dry place. When you say using a paper towel, what was that for. I am trying to figure out your system of finishing this piece. I wish you would post some photos and maybe we can help.  

[Goat]

12 minutes ago, JTTHECLOCKMAN said:

https://www.homedepot.com/p/Zinsser-12-oz-Clear-Shellac-Spray-408/100176744

If this is the stuff you are using I am at a loss. I use this all the time and never had a problem. It dries to the touch in about 10 minutes. You spray a light coat on and if need more again light coats. You say you left it outside. Is it humid or moisture in the air. Any moisture or dew in the air is not good for any finish. The smell is not bad at all. I spray in my basement shop and never smell it in a couple minutes it is gone. Did you shake the can?/  What is underneath this finish??  Did you oil the project before using the shellac. ??? Something is not right here. I suggest you spray a seperate piece of wood and see what the results are. Do nothing to the wood. Just spray it. If that does not dry either than you have a bad can of spray. That stuff has a shelf life of about 1/2 year if stored in cool dry place. When you say using a paper towel, what was that for. I am trying to figure out your system of finishing this piece. I wish you would post some photos and maybe we can help.  

The frames have minwax true black stain applied which dried for 24 hours before the shellac was applied.  Then I have BB plywood with nothing on it.  The towel was to protect the finished pieces as I was gluing the BB to a backer and it was not laying totally flat, so I had to weigh it down while it dried.  I just purchased from home depot.  I also just check them again and I can still press down on the paper towel and leave a mark in the finish.  The pieces were all moved inside the house around 10am, so plenty of time to dry some more.

 

I already applied more shellac to remove the marks, but so far with my experience once I hit the 3-4 coat mark this stuff seems to stay soft.  Maybe my coats are too light, but at 2 coats the finish still doesn't look very even.  So 3-4 seems to be the sweet spot.

[JTTHECLOCKMAN]

Wow. Light coats is always the way to go with any finish. Proper spray technique is crucial to get an even coat with no orange peel effect. To me shellac is just an undercoating and does not protect a project well from scratches. I like to top coat with Lacquer after a couple coats of shellac. 

I am at a loss for your project. Adding more coats to something that has not dried underneath just compounds the problem. I know spraying Zinnser is not easy to get even coats. That is why I said proper technique is important. But the drying thing is what is puzzling because the base mixture is alcohol and shellac flakes. Alcohol as we all knows flashes over very quickly. The only thing I can tell you is with shellac it does have a shelf life that is critical or else it will take a lot longer to dry or always remain soft. Now with Zinnser they say 3 year shelf life on spray cans is normal but I know brush on cans it is 6 months. here is a code decifer for their cans. You may want to check the date yours was made. I am sorry that is all I have for you unless you want to strip down and try again. You may have to strip it if it does not cure. Good luck.

 

A typical code found on a can lid might be S0720BD. The first number after the letter is the year the shellac was mixed. In this case, you see 0 which indicates 2010. If the number was 1, it would represent 2011, and 2 would indicate 2012. The first number after the year indicator is the month of mixture. In the example, 7 indicates the month of July. The numbers 1 through 9 stand for January through September, 0 indicates October while N is for November and D for December. If you need more in-depth information, the two numbers that follow the month indicator tell you the exact date of manufacture.

[kmmcrafts]

I don't dip portraits usually.. Well that's sort of a lie.. If I use a painted backer.. I glue the portrait to the painted backer and then top coat both with water base polyurethane or lacquer.. If I use a contrasting wood color as a backer I glue first then either dip or spray.. But that said.. I do only use 1/8" for the cutting and if a framed piece then I use another 1/8" for backer.. 

[Goat]

6 hours ago, JTTHECLOCKMAN said:

Wow. Light coats is always the way to go with any finish. Proper spray technique is crucial to get an even coat with no orange peel effect. To me shellac is just an undercoating and does not protect a project well from scratches. I like to top coat with Lacquer after a couple coats of shellac. 

I am at a loss for your project. Adding more coats to something that has not dried underneath just compounds the problem. I know spraying Zinnser is not easy to get even coats. That is why I said proper technique is important. But the drying thing is what is puzzling because the base mixture is alcohol and shellac flakes. Alcohol as we all knows flashes over very quickly. The only thing I can tell you is with shellac it does have a shelf life that is critical or else it will take a lot longer to dry or always remain soft. Now with Zinnser they say 3 year shelf life on spray cans is normal but I know brush on cans it is 6 months. here is a code decifer for their cans. You may want to check the date yours was made. I am sorry that is all I have for you unless you want to strip down and try again. You may have to strip it if it does not cure. Good luck.

 

A typical code found on a can lid might be S0720BD. The first number after the letter is the year the shellac was mixed. In this case, you see 0 which indicates 2010. If the number was 1, it would represent 2011, and 2 would indicate 2012. The first number after the year indicator is the month of mixture. In the example, 7 indicates the month of July. The numbers 1 through 9 stand for January through September, 0 indicates October while N is for November and D for December. If you need more in-depth information, the two numbers that follow the month indicator tell you the exact date of manufacture.

1 of the 7 frames I made feels dry now, the others feel tacky.  Not so tacky that something would stick to them, but a clear difference when rubbing your hand across them vs a dry piece.

 

Do you think running a fan on them or heat gun would help?  I need to deliver them Saturday and not sure what to do.  Would they eventually harden in a week or so?  I could just tell them the finish will need time to cure before they really handle them.

 

The brush on says S91XXX, the spray cans I need to dig out of the trash and see.

[OCtoolguy]

I don't mean to butt in but I just finished a small jewelry box made of ash and some other woods. I oiled it with Watco, let it dry for 2 days and then put Zinnser's clear shellac on it. It dried in minutes so I could put another coat on it. My can is about 2 years old and still seems ok. Maybe it is darker now but I have nothing to compare to. Anyway, something is wrong with your application. JMHO.

[JTTHECLOCKMAN]

4 hours ago, Goat said:

1 of the 7 frames I made feels dry now, the others feel tacky.  Not so tacky that something would stick to them, but a clear difference when rubbing your hand across them vs a dry piece.

 

Do you think running a fan on them or heat gun would help?  I need to deliver them Saturday and not sure what to do.  Would they eventually harden in a week or so?  I could just tell them the finish will need time to cure before they really handle them.

 

The brush on says S91XXX, the spray cans I need to dig out of the trash and see.

It can not hurt to try. Other than that I am sorry but have nothing else. I have not seen this. 

[kmmcrafts]

I had a similar instance with Shellac.. but it is more user error ( at least for me ) than the Shellac..

I was trying to get a nice shiny coat on all the inside cuts while trying to get a nice even spray all around it.. What was happening was some areas was really soaking in.. ( I'm used to painting metal at the time (cars) and just kept spraying coats on it. ) I got the shellac on the piece so thick it took a really long time to dry.. Not like the typical times.. Also think it was Cedar and maybe some of the woods sap was interfering a bit too?

Anyway... this was like my first time with finishing wood and I did it all wrong.. You see.. with cars.. you paint it till it's got a nice shine.. and a even coat and shine throughout.. what it looks like with wet paint is how it'll look dry.. so I was trying to get the look as if I was painting a car.. I think I put on about 2+ full cans of spray shellac on that one piece I made..LOL

[JTTHECLOCKMAN]

With shellac it will block just about anything so I do not believe that is the problem here. As far as spraying the next coat, you let the previous coat dry to the touch. If you can touch it and it is not sticky then you can add the next coat if it needs it. You do not top coat something that is still wet. Shellac dries so fast because of the alcohol evaporates so fast and this is what is puzzling to me. Unless the coats were applied so thick they did not have a chance to dry underneath. 

[Goat]

1 hour ago, JTTHECLOCKMAN said:

With shellac it will block just about anything so I do not believe that is the problem here. As far as spraying the next coat, you let the previous coat dry to the touch. If you can touch it and it is not sticky then you can add the next coat if it needs it. You do not top coat something that is still wet. Shellac dries so fast because of the alcohol evaporates so fast and this is what is puzzling to me. Unless the coats were applied so thick they did not have a chance to dry underneath. 

It could be.  I have little experience with this stuff so what I feel is a light coat might be heavy.  At least with the brush I found it almost impossible to apply a "light" second coat as it was really hard to move the brush.  If I added a bit more it would glide super smooth.

 

Whats odd is I rubbed it with my hand several times and it took away allot of the tackiness.  I then used a heat gun on low heat and did a quick pass.  It felt perfect a few seconds after the heat, but did start to feel like before after sitting.  I'm going to leave a fan on them all night and see what happens.

 

edit:  I posted what I have been working on in bragging rights.

Edited June 21, 2019 by Goat