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Forum topic by Jermey posted 03-05-2017 03:55 AM 1140 views 0 times favorited 18 replies Add to Favorites Watch
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Jermey

8 posts in 329 days


03-05-2017 03:55 AM

Topic tags/keywords: question help

So I began making a table a month or so ago from a plan on Ana White’s website. I tailored it a bit to use a farmhouse table top. However, now that I am almost done with the table, I am having a “wiggling” issue. This table only has one main point of weight bearing. A 4×4 in the center of the table with angled beams branching off of it. I am wondering if there is a way to stop this wiggling from happening without deconstructing the entire table or ruining the design of it. I attached pictures of the underneath in order to show you how it is attached to the table and a video to show how it moves. Right now I have it attached on all four corners with a hex bolt and on the underside of the table, there are insert nuts. Any help would be greatly appreciated as I am very desperate at this point. Video: https://www.flickr.com/photos/80258781@N03/shares/RX2290 IMG_2209IMG_2207


18 replies so far

View papadan's profile

papadan

3584 posts in 3206 days


#1 posted 03-05-2017 07:40 AM

Is the whole base assembled with pocket hole screws only? It looks like the base is made of Pine, is it? The base should be glued along with the pocket hole screws because of twisting against the screw connections. If the base is Pine, that is your biggest problem. Pine is a soft wood and very flexible, I would recommend replacing at least the center post with Oak or maple. A hardwood post wont twist like that. If need be, you can build the center post by gluing up hardwood lumber instead of trying to find a 16/4 post.

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Jermey

8 posts in 329 days


#2 posted 03-05-2017 08:12 AM



Is the whole base assembled with pocket hole screws only? It looks like the base is made of Pine, is it? The base should be glued along with the pocket hole screws because of twisting against the screw connections. If the base is Pine, that is your biggest problem. Pine is a soft wood and very flexible, I would recommend replacing at least the center post with Oak or maple. A hardwood post wont twist like that. If need be, you can build the center post by gluing up hardwood lumber instead of trying to find a 16/4 post.

- papadan


It is assembled with pocket hole screws and wood glue. Also, the material is pine. I will have to head to the store in the morning and test out some oak. Thank you for your suggestions!

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Rick_M

10634 posts in 2218 days


#3 posted 03-05-2017 08:31 AM

Anna White is not a good source for plans but that said, her plan calls for an 8×7 base which you downsized to 4×4. But, those angled braces should be stiff if their connection to the top and column are tight and strong. Pine is not your problem. I’m on mobile and your pics are really dark so I can’t see much. Can’t see the video either because it requires a yahoo account. I don’t have enough information how is the top support built and how does it attach to the pedastal?

-- http://thewoodknack.blogspot.com/

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Jermey

8 posts in 329 days


#4 posted 03-05-2017 09:00 AM



Anna White is not a good source for plans but that said, her plan calls for an 8×7 base which you downsized to 4×4. But, those angled braces should be stiff if their connection to the top and column are tight and strong. Pine is not your problem. I m on mobile and your pics are really dark so I can t see much. Can t see the video either because it requires a yahoo account. I don t have enough information how is the top support built and how does it attach to the pedastal?

- Rick M


I’m not sure what you mean when you say an 8×7 base. This is the plan I was basing my work off of: http://www.ana-white.com/2013/07/plans/square-x-base-pedestal-dining-table

The center support is a 16/4 post. The post is connected to the top “X” with 8 pocket hole screws – 2 on each face. It is also connected to the base “X” in the same way. The angled braces are connected with pocket 4 pocket holes each – 2 on each end. The entire base needed to be able to come off as one piece from the top of the table as it needs to fit through a doorway for transporting so for this I used hex bolts. I used one hex bolt per side (4 in total) to attach the base to the table top. Additionally, I used insert nuts in the base of the table as the securement for the hex bolts. Was it a mistake to use pocket holes as my source of attachment for the base? I have included a brighter picture of the underneath. I hope this helps (apologies if they come out sideways). Thank you for your reply.

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Tony_S

766 posts in 2921 days


#5 posted 03-05-2017 11:33 AM

I am wondering if there is a way to stop this wiggling from happening without deconstructing the entire table or ruining the design of it.
- Jermey

No. As you’ve discovered, structurally it’s a piss poor design to begin with. The 3 1/2” center post is WAY too small for table top that size(Regardless of materials and joinery). That, and a combination of butt joints and pocket screws equals a combination for failure.
There are reasons why most pedestal table bases are so large and bulky, and this is one of them.
The only thing I can think of that would ‘help’, without tearing it apart and building it properly, would be to fit in 4 more vertical 4×4’s against each face the center post with 45’s cut top and bottom to fit the cross braces. Fit snugly, glue and screw the hell out of it.

Swearing at the table, and yourself the entire time you’re doing it sometimes helps as well…..

-- It is the mark of an educated mind to be able to entertain a thought without accepting it. Aristotle

View Lazyman's profile

Lazyman

1504 posts in 1225 days


#6 posted 03-05-2017 12:58 PM

Based upon the video, unless the screws that attach the top to the base are not tight, it looks to me like the vertical 4×4 is simply twisting as you torque the top. The post is probably twisting less than 1 degree but is exaggerated by the width of the table. Without changing the design in some way, there is probably nothing you can do about that. Only thing that I can think of that might help but might not completely eliminate the twisting is to make the angled braces connect to post at right above the lower ones. That may shorten the amount of wood that can twist and minimize it as much as possible without completely scraping the base. You will probably have to change the angles on those braces from the current 45 degrees angles (different angles on the top and bottom) to prevent them from hitting your knees but they could still be in the way. Maybe lengthening the both the top and bottom braces so that the meet in the middle would minimize the knee banging potential? Of course, if they are already glued on, you may be out of luck. Or you can just accept that this is the way it is going to be.

I guess you have figured out that Anna Whites designs are not highly thought of on LJs. You are not the first person to reach out here asking for help to fix the flaws in one of her designs. Some people like the way her designs look but they usually have flaws that violate rules that most experienced woodworkers know not to do. Sometimes, we gain that experience the hard way. Good luck.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

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jdmaher

417 posts in 2417 days


#7 posted 03-05-2017 03:23 PM

Regardless of how you got to this point, it does seem that what you have should be far less “wiggly” than your video shows.

I’m guessing that you are off-camera twisting the top? It LOOKS like the top is not secured to the base, but we should check that.

Can you take the top off and check for movement in just the base? I’d put my feet on two adjacent legs and try – gently – to twist the two corresponding adjacent arms. If there is movement, try to identify the source. Is the center post twisting? Or are just the arms moving? If it is the arms, are all four moving, or just the two you are applying pressure to?

I’m not sure how sturdy the design will be over time, but – right now – it sure LOOKS like there are some loose connections somewhere. I believe you ought to be able to tighten it up quite a bit.

-- Jim Maher, Illinois

View TheFridge's profile

TheFridge

8323 posts in 1324 days


#8 posted 03-05-2017 03:54 PM

This isn’t the first or last time someone has wanted to fix an Ana white design so don’t feel bad.

Good luck

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View simoncpj's profile

simoncpj

10 posts in 350 days


#9 posted 03-05-2017 04:08 PM

An different way to look at this with a positive spin. Leave it as is, that flex will likely have no practical impact except when you bash your hip into the edge of the table as you walk by it will give just enough that you merely grunt instead of yelp.

View a1Jim's profile

a1Jim

116578 posts in 3415 days


#10 posted 03-05-2017 04:21 PM

Ana White makes some great looking designs but she does not know anything about traditional woodworking joinery or wood movement
I know as a new woodworker this can be very disappointing to have a substandard product after taking the time to build a project. Short of taking it apart and adding loose tenon joinery the best suggestion I have is to add some 3/8”x 5”-6” lag bolts at each joint close to where you have pocket screws on all of the 4×4s. if you counter sink them you can put wood plugs in to hide the heads of the lag bolts, just check whatever length you use to make sure they don’t go all the way through the connecting 4×4.

I would suggest you post on her web-site they problems you had after spending all your time and money to build this table and maybe a link to this thread just to save others from having the same problem.
best of luck

-- http://artisticwoodstudio.com Custom furniture

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firefighterontheside

16941 posts in 1694 days


#11 posted 03-05-2017 04:37 PM

It looks like the 4×4’s that make the cross that sits on the floor are straight on the bottom. Put some kind of feet at the ends of the 4 pieces. Thick felts pads may be all that is needed or you could fashion some out of the same wood and glue them on. If there’s any unevennness to the floor the table is gonna rock on it without feet.

-- Bill M. "People change, walnut doesn't" by Gene.

View clin's profile

clin

751 posts in 834 days


#12 posted 03-05-2017 04:49 PM

Looks like a design flaw. While all those diagonal members give a lot of support to prevent tipping, they do very little to prevent twisting. Every joint has some give, and in this case a little give on these small joints ( small relative to the table top), translates to a lot of movement on the top.

It may be it’s just a combination of a little movement on these joints and some flex in the wood. There may be nothing you can do to it. But adding blocking, to tightly trap the top of the post, might help reduce twisting at the top. These wouldn’t normally be seen. I’m thinking in terms of filling in the small open triangles formed between the post, top, and diagonals.

These would effectively create a pocket that the end of the post fits into and would at least ensure the end of the post can’t twist.

These would help at the bottom, but would be seen and alter the look. But if done well, I don’t think it would look bad.

But there is a reason pedestal tables usually have much larger pedestals. You’re asking a lot if a 4×4 post.

-- Clin

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TheFridge

8323 posts in 1324 days


#13 posted 03-05-2017 05:52 PM

Pocket screws aren’t great against racking.

Lag bolts like Jim said or spax screws at the very least. I’d go lags with plugs.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View Loren's profile (online now)

Loren

9631 posts in 3486 days


#14 posted 03-05-2017 06:01 PM

Try to isolate the movement.

I’d start by cutting 4 pieces of 2×4 with 45
degree ends and clamping them around the
center column to see if beefing that up
will help.

View ScottM's profile

ScottM

565 posts in 1984 days


#15 posted 03-05-2017 06:13 PM


Regardless of how you got to this point, it does seem that what you have should be far less “wiggly” than your video shows.

I m guessing that you are off-camera twisting the top? It LOOKS like the top is not secured to the base, but we should check that.

Can you take the top off and check for movement in just the base? I d put my feet on two adjacent legs and try – gently – to twist the two corresponding adjacent arms. If there is movement, try to identify the source. Is the center post twisting? Or are just the arms moving? If it is the arms, are all four moving, or just the two you are applying pressure to?

I m not sure how sturdy the design will be over time, but – right now – it sure LOOKS like there are some loose connections somewhere. I believe you ought to be able to tighten it up quite a bit.

- jdmaher

I agree with this. Bad design or good design, you need to figure out where the “wiggle” is coming from. I could see it moving in the video but couldn’t see anything flexing or moving in the base.

So, get a helper. Don’t cut, rebuild, or disassemble anything at this point!! You get on the floor underneath the table and have your helper twist it as you did in the video. Put your fingers on each joint one at a time, at the floor and at the base of the top, as it’s being twisted from your helper. Many times you can feel what’s happening better than seeing it and letting your head make a decision on what’s happening.

I don’t have any suggestions on how to fix this but you’ve really yet to discover what the problem is. You’ll have to find the problem first before you can figure out how to fix it or what it will take to fix it.

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