Woodworking Talk banner

1 - 14 of 14 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
i'm a consumer with my first wood project. i have a 1" poplar table top finished with 4 layers of polyurethane. i was attaching table base which required A LOT of screws at specific areas. i'm pretty sure that every screw (10?) except the last one are NOT between glued boards. the final screw (!) just so happened to be needed between two boards. you can tell by the grain difference (black vs coffee). it was late and i was tired so i put the screw. table looks OK. it goes 1 cm deep and the table thickness is 2.54 cm so 40%. my question - will there be splitting in the future and can i do anything to stop that from happening? this screw is near an area of the desk that will be used a lot.

i have not made up my mind if i want to use the inward cut for my body (to come closer to the desk) to support my arms or turn it around and put a monitor arm there (box of measuring tape is where i'll put the monitor arm if i go that route).

i won't repeat this mistake again. thank you!

photo of the screw. it goes 1 cm deep into wood that is 2.54 cm thick (40%).



photo of the hole



zooming in the hole. i'm guessing the wood boards are glued with gorilla glue. the hole was made 2 weeks after gluing and 1 week after the finish was cured.



the screw hole is near the semi circle cut. you can tell by the dark and coffee colored grains being next to each other.



the measuring tape is where the monitoring arm will be C clamped if i go that route. will putting weight at this portion damage the wood board?



photo of the desk as a whole. i don't see any signs of splitting but i hope that will be true 1 year later!



next time i'll get a more simple table base with less screws!

thanks again!
 

·
Registered
Joined
·
611 Posts
If the joint was glued properly ( and it looks like it was) then I don't think you have anything to worry about. Generally the glued joint is stronger then the wood it's self.

Good looking table, I like it.
 

·
Registered
Joined
·
300 Posts
I agree with Big Bull, shouldn't be a problem unless there's a great deal of overhang where you plan on putting the monitor arm. Did you pilot drill for the screws? The amount of raised wood around the hole in the picture looks like you might not have.

Just my 2 cents.

joe
 

·
Registered
Joined
·
18 Posts
Discussion Starter #4
thanks for the feedback!

no, i did not use pilot holes. another layman's mistake. 4 screws went in each of the two sides and they went .75 inches into wood that is 1 inch thick. there was some initial vortex feel with the power drill but after some point the screw went in smoothly.

i just read that screwing without pilot holes can split the material. i hope that does not happen. this is another mistake i will not repeat. i should not have made these dumb mistakes on such a nice piece of poplar.

as for the support, i removed one support beam because it got in the way of my legs. the table still seems pretty steady and i am keeping an eye on it. it is like a really wide H. most of the support comes from the sides and then there is a minor beam in the middle which doesn't seem to do much for strength.





let me know if you think this is too much overhang. if i put the monitor arm there, it will be 8 lbs for the arm and 13 lbs for the 24" monitor. i have not made any final decisions on this because i don't want to damage the wood but the wood does feel pretty stiff (just don't know if it can handle a monitor 24/7 over time).
 

·
Registered
Joined
·
18 Posts
Discussion Starter #5
here are some more photos of the bottom support. the sides of the wide H have 8 screws which go .75" into the 1" thick board. next time i will use pilot holes!



 

·
Registered
Joined
·
26,375 Posts
The screw you are worried about is next to the joint so it should affect it. You have enough screws already, you could Just leave that one out to be on the safe side.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #7
The screw you are worried about is next to the joint so it should affect it. You have enough screws already, you could Just leave that one out to be on the safe side.
I ended up having to remove that screw for different reasons as well. i'll just leave it like that and do nothing so that I don't damage anything.

i'm new to all this so please bear with me...how does removing the screw make it any better when the hole made by the screw will always be there anyway? should I do anything like put some polyurethane finish into the hole? I don't want something to expand and damage.

so far no cracks...how long should I observe for cracks before it is likely that there won't be cracks (no guarantees but likelihood). I read somewhere that by 6 months wood will have done what it wants to do e.g. crack.
 

·
Registered
Joined
·
26,375 Posts
The screw in the hole puts a little pressure on the surrounding wood especially if the wood shrinks a little. Not having the screw in the hole relieves any pressure there might be there. A lot of times you can split wood by putting in screws without predrilling a pilot hole. It's kind of like a steel wedge driven in the head of a wood handled hammer but a much smaller scale.

You don't need to do anything with the finish. Just leave it like it is.

The biggest risk you have with a table top like that is the amount of screws you have and if the screws are tight to the holes in the metal. The wood is likely to shrink over time and if you have each side of the top firmly screwed to the metal when the wood shrinks the top splits in the middle because the sides can't move inward. A lot of folks create elongated holes in the metal and barely snug the top to the metal. That way if and when the wood shrinks the outer part of the top can move inward. The amount of shrinkage you will experience is likely to be small and if there is a little slop in the screw holes in the metal it will probably be enough. Sometimes if you just barely put enough screws in and the top shrinks the wood will just give around the holes instead of splitting the wood. The pressure has to go somewhere.
 

·
Old Methane Gas Cloud
Joined
·
3,500 Posts
The joint is as strong as the wood and the screw's position is not that important.

What is very important is what Steve is saying about wood movement.

Here is a simple solution to the problem. Remove the top and elongate the holes in the metal. Except for the center holes, the other holes need to be oval and about 6-8 mm long. then re-attach the top. Make the center screws rather tight but the screws away from the center need a washer and be just snug. When re-attaching the top offset it about a Cm front to back. No one will notice and you'll have fresh wood to drive the screws into.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #10 (Edited)
The biggest risk you have with a table top like that is the amount of screws you have and if the screws are tight to the holes in the metal...The pressure has to go somewhere.
thank you for the education. this is all new to me. i will have to do some background reading in the forum to avoid asking you too many rudimentary questions.

i have loosened all the screws down so there is a gap of .25". despite that, the screws are still very tightly planted to the wood and they don't move at all. i felt a lot of pressure release as i was loosening the screws. the table still is very steady and stable so i could probably loosen the screws even more.

the metal holes are 1 cm in diameter and are noticeably bigger than the diameter of the screws (see photo below for comparison). do I still need to elongate?

A lot of times you can split wood by putting in screws without predrilling a pilot hole. It's kind of like a steel wedge driven in the head of a wood handled hammer but a much smaller scale.
i have made 8 holes on each side without using pilot holes. so far no signs of cracking and I have tried to follow your advice about making space for wood to contract. can i consider myself lucky or will it be a matter of 6 months when cracks form?

out of the 16 holes, i messed up on one and had to make another hole just 7.5mm away. as precaution, I have removed the screw from this and am leaving it empty. in fact, even though I have 8 holes on each side, I have only 4 screws in and 4 holes empty because I removed the screws. the table is still very stable so that's no worry.





these holes are .75" deep when the wood thickness is 1". i should have thrown away the screws that came with this base and purchased shorter ones. i was too eager to get the table ready. i'm come to accept the fact that this wood is probably ruined and will eventually crack due to my sloppy work.

in the future, if cracks begin to form i will cut off 3" of each side (because that's where the screw holes are lined up) + 2" buffer so 5" total on each side and then have the shop glue new boards on the side to make this like new again.

i will use this as a learning experience. i'm just a consumer who purchased wood for the first time that is not from ikea. as a layman, i thought it was a simple matter of screwing the base to the wood. now i realize i should have done a little more planning. i apologize to all woodworkers out there for butchering this beautiful piece of wood due to my ignorance. i won't repeat these mistakes next time.
 

·
Registered
Joined
·
26,375 Posts
I think you will be alright on the table. If the holes are 1 cm they have engineered wood movement in the framework. There shouldn't be any need to elongate the holes. A lot of what I was telling you was for future reference. As long as there is enough slack in the screws about the thickness of a sheet of paper it should allow the wood to breath. Normally on a piece of furniture the framework is wood also and there is a some give to it. With the table you have the steel is going to stay the same as it is while the wood top is going to swell up in humid weather and shrink in dry weather and over time the width of the top is going to get smaller . It's just the nature of wood.

As far as the screws are from the end of the top the screws are not likely to cause cracks.
 

·
I wood if I could.
Joined
·
3,976 Posts
thank you for the education. this is all new to me. i will have to do some background reading in the forum to avoid asking you too many rudimentary questions.

i have loosened all the screws down so there is a gap of .25". despite that, the screws are still very tightly planted to the wood and they don't move at all. i felt a lot of pressure release as i was loosening the screws. the table still is very steady and stable so i could probably loosen the screws even more.

the metal holes are 1 cm in diameter and are noticeably bigger than the diameter of the screws (see photo below for comparison). do I still need to elongate?



i have made 8 holes on each side without using pilot holes. so far no signs of cracking and I have tried to follow your advice about making space for wood to contract. can i consider myself lucky or will it be a matter of 6 months when cracks form?

out of the 16 holes, i messed up on one and had to make another hole just 7.5mm away. as precaution, I have removed the screw from this and am leaving it empty. in fact, even though I have 8 holes on each side, I have only 4 screws in and 4 holes empty because I removed the screws. the table is still very stable so that's no worry.





these holes are .75" deep when the wood thickness is 1". i should have thrown away the screws that came with this base and purchased shorter ones. i was too eager to get the table ready. i'm come to accept the fact that this wood is probably ruined and will eventually crack due to my sloppy work.

in the future, if cracks begin to form i will cut off 3" of each side (because that's where the screw holes are lined up) + 2" buffer so 5" total on each side and then have the shop glue new boards on the side to make this like new again.

i will use this as a learning experience. i'm just a consumer who purchased wood for the first time that is not from ikea. as a layman, i thought it was a simple matter of screwing the base to the wood. now i realize i should have done a little more planning. i apologize to all woodworkers out there for butchering this beautiful piece of wood due to my ignorance. i won't repeat these mistakes next time.
You have nothing to apologize for. You did things most other "common men" won't do: you tried! So you're already a better woodworker than the average common man. Next, you're asking genuine and relevant questions, which shows you care and have interest in doing it right. Even though the concerns weren't apparent to you from the start, or so it seems, they did occur to you at the end. So you're interested and keen enough to see that there is a hidden underbelly to even basic woodworking. We like guys like you to be here. Definitely nothing to apologize for :thumbsup:

You most likely will not experience cracking if it didn't occur during assembly. But it is possible that a break might occur when natural seasonal swelling and shrinkage manifests. Only time will tell at this point. I wouldn't lose sleep worrying about it though. Odds are you're fine.

Pre-drilling would have been your best move though. Unless the screw is "self tapping" or "self drilling" (or something like that) you should drill a pilot hole. The thinner the wood - and the thicker the screw - the more critical pilot holes become. That varies somewhat, depending on the characteristics of the wood. Some woods are much more brittle and prone to splitting than others.

And drilling for counter-sunk heads is even more important to avoid undue risk of splitting. But that doesn't apply in this case.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #13
You have nothing to apologize for. You did things most other "common men" won't do: you tried! So you're already a better woodworker than the average common man. Next, you're asking genuine and relevant questions, which shows you care and have interest in doing it right. Even though the concerns weren't apparent to you from the start, or so it seems, they did occur to you at the end. So you're interested and keen enough to see that there is a hidden underbelly to even basic woodworking. We like guys like you to be here. Definitely nothing to apologize for :thumbsup:

You most likely will not experience cracking if it didn't occur during assembly. But it is possible that a break might occur when natural seasonal swelling and shrinkage manifests. Only time will tell at this point. I wouldn't lose sleep worrying about it though. Odds are you're fine.

Pre-drilling would have been your best move though. Unless the screw is "self tapping" or "self drilling" (or something like that) you should drill a pilot hole. The thinner the wood - and the thicker the screw - the more critical pilot holes become. That varies somewhat, depending on the characteristics of the wood. Some woods are much more brittle and prone to splitting than others.

And drilling for counter-sunk heads is even more important to avoid undue risk of splitting. But that doesn't apply in this case.
Thank you so much for the kind words. I really appreciate it. I am looking forward to learning a lot in this forum. :thumbsup:
 

·
Maker of sawdust
Joined
·
460 Posts
Washers

I you feel that you need to back out the screws the thickness say the width of a washer it might be worth your time to take up that slack by.
1. pulling the screw/s getting washers them put washers on the screws
2. Put screws back in holes with washers in place, washers on the back side away for the wood carefully retighten.
3. this one is cosmetic more than anything else. on the market there are putties and pencils that come in a wide array of colors are inexpensive and will fill that tiny hole don't sand it fill slightly deeper than the hole that way if it is to light or dark you won't have to remove it. If it is the color that you want sneak up on it so to speak so that it fills the hole and little or no clean up is required if not then a shade light or darker. on then it will look like silk.

Jerry
 
1 - 14 of 14 Posts
Top