Joining plywood top/bottom with cherry panels - Woodworking Talk - Woodworkers Forum
 
Thread Tools Display Modes
post #1 of 7 Old 05-28-2012, 02:58 PM Thread Starter
Junior Member
 
Join Date: Oct 2008
Location: VA
Posts: 9
View fr8train's Photo Album My Photos
Joining plywood top/bottom with cherry panels

Gentlemen (and ladies).

Happy Memorial Day to all of you.

I am in the process of making a (mostly) solid cherry entertainment center..... the "mostly solid cherry" is where I am running into an issue.

I designed this as I went along, and realized that I might have two problems that I didn't forecast:

a) a joining problem between the plywood top and bottom with the solid cherry sides (cherry expanding/contracting with changes in humidity and the plywood not doing so). The carcass is birch plywood on the top and the bottom, but my sides and middle sides I made out of solid cherry boards. My plan was to glue the plywood to the simple dado joints I made in the cherry sides and then to reinforce with pocket-hole screws. Now that I am thinking about it, I think that this might not allow for the expansion/contraction of the cherry sides and the sides may crack over time.

b) Related to the expansion/contraction of the sides, my drawer slides (attached to the cherry side panels) were going to follow the same concept.... simple strips of plywood either glued or screwed to the inside of the solid cherry sides..... apparently, however, this will not allow for the expansion of the wood. The attached link only sunk my heart further, as the diagram on page 19 of this article was exactly what I did last night.... luckily for me, I didn't glue the drawer slides up, but simply attached the strips with screws (as I planned on finishing both sides of the panels as mentioned before).

http://www.extension.purdue.edu/extm...NR/FNR-163.pdf

Necessary Background information:

There are four solid wood panels (two outside and two inside). They are all constructed of solid cherry boards, planed to about 3/4" and measure 20" in width with the boards running in a vertical direction. The expanding and contracting problem is horizontal.

I didn't yet treat the cherry or the plywood. I plan on shellacing both sides of the cherry wood for sealer, then using a water-based dye on the show sides of the panels to slightly darken the cherry, finishing coat using shellac again. This, I believe, will have slightly minimize the amount of expanding and contracting.

I constructed a solid cherry top, but don't forecast having an expansion/contracting problem with it as I am drilling a series of oversized holes in the top of the carcass and will attach it the top from underneath so it "floats" on top of the carcass.

The big questions are for both problems..... how do I join the plywood top and bottom carcass and how do I join the drawer slides to the solid panels so the panels don't crack over time and yet my cabinet will remain solid?

I figure that I might be able to oversize the screw holes in the drawer slides, but I am worried that this will cause too much shift.... the drawers are rather heavy (constructed of poplar with cherry faces).

I have no idea what to do about joining the solid side panels with plywood top and bottom.

Any help would be greatly appreciated. Thanks again!

FR8

Last edited by fr8train; 05-28-2012 at 03:11 PM.
fr8train is offline  
Sponsored Links
Advertisement
 
post #2 of 7 Old 05-28-2012, 03:34 PM
Old School
 
cabinetman's Avatar
 
Join Date: Jul 2007
Location: So. Florida
Posts: 24,027
View cabinetman's Photo Album My Photos
Before I address your question, I have one. What's so 'happy' about Memorial Day?





.
cabinetman is offline  
post #3 of 7 Old 05-28-2012, 08:41 PM Thread Starter
Junior Member
 
Join Date: Oct 2008
Location: VA
Posts: 9
View fr8train's Photo Album My Photos
Quote:
Originally Posted by cabinetman View Post
Before I address your question, I have one. What's so 'happy' about Memorial Day?





.
Not sure what you are getting at, cabinetman, but remembering those that have served this great nation doesn't have to be - nor it should be - a sad affair..... I guess I don't know what the proper greeting is for Memorial Day..... I noticed the patch on your avatar.... we are brothers at arms.... I am still serving...27 years and several combat tours later ..... and I have plenty of fallen brothers that I remember (with pleasure) on this day.

FR8
fr8train is offline  
Sponsored Links
Advertisement
 
post #4 of 7 Old 05-29-2012, 04:06 PM
Senior Member
 
Join Date: Aug 2009
Posts: 287
View Zircon's Photo Album My Photos
Perhaps make the carcass completely out of plywood and then attach the solid sides in the same way that you are attaching the top with elongated holes? If the inside has to look good use cherry plywood.
Zircon is offline  
The Following User Says Thank You to Zircon For This Useful Post:
fr8train (06-02-2012)
post #5 of 7 Old 05-31-2012, 07:07 PM
Junior Member
 
Join Date: May 2012
Location: New Hampshire
Posts: 4
View Jay Gauthier's Photo Album My Photos
you could make a shiplap edge where your boards will meet each other in the middle so they will overlap and then leave a space about 1/8 of an inch and allow them to "float". where your top and bottom plywood sits in your dado, you will most likely have a baseboard and a top trim piece. If so you can put a screw into the plywood from the outside of the carcass. put a screw in the middle of the vertical solid boards and then an oversized screw hole at each end to allow for movement. So you will end up with 3 screws per board on the top and bottom and in the middle if you are putting a middle shelf in. your trim should cover the screws and should be easier than pocket hole screws from the inside.

As far as the drawer slides go, I would put a face frame of 1 5/8 inch which would leave a 1/8 inch lip on the outside and use pocket holes to attach a 3/4 inch board on the inside to attach your drawer slides. The pocket holes will screw into the face frame and then make a couple of oversized holes in the board and screw into the middle of your vertical boards as the middle of your boards will have the least expansion and contraction.

I made a cherry coffee table for my inlaws about 8 years ago and the top was made up of three 8 inch boards glued together and held on with oversized pocket hole screws and they live a half mile from the ocean and the top is as good as new. I have seen no evidence of movement and yes I turn the table upside down to check when I visit. Always nice to see how your projects are holding up.

I hope I explained this so you can understand. Good luck and let me know if you have any questions

Also thank you for your service to our country.
Jay Gauthier is offline  
The Following User Says Thank You to Jay Gauthier For This Useful Post:
fr8train (06-02-2012)
post #6 of 7 Old 06-02-2012, 03:28 AM Thread Starter
Junior Member
 
Join Date: Oct 2008
Location: VA
Posts: 9
View fr8train's Photo Album My Photos
Thanks for the help..... I really appreciate the detailed explanation.

Here is what I came up with..... Picture speaks a thousand words.....

I can do a slight redesign (everything is already cut.... drawers, shelves, doors, etc. so I don't want to go into the majors redesigning the whole thing). I can add support to the top and bottom then attach the support to the sides using brass threaded inserts and slots in the support.

The first (amateur) drawing is the front view of the carcass..... the second is a side view from the inside of the carcass with the "repairs" I had in mind...

The drawing to the right shows the support (E) attaching A (Side) to B (top), but I would use the same concept to attach A to C (bottom), D (Middle vertical panel) to B, and D to C on both sides of the carcass.

Opinions are welcome!

Thanks again for the help.
Attached Images
  

Last edited by fr8train; 06-02-2012 at 03:33 AM.
fr8train is offline  
post #7 of 7 Old 06-03-2012, 08:17 AM
Junior Member
 
Join Date: May 2012
Location: New Hampshire
Posts: 4
View Jay Gauthier's Photo Album My Photos
Looks good. Nice drawing. I would still shiplap your boards where they butt together in the middle to allow for expansion and then you won't have any see through gaps when they do.
Jay Gauthier is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Woodworking Talk - Woodworkers Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Joining two panels? Best joint? Drillbit General Woodworking Discussion 14 03-07-2011 11:04 AM
Plywood For Raised Panels cabinetman General Woodworking Discussion 10 02-13-2010 07:36 AM
Joining plywood Bob Willing Joinery 19 10-25-2009 08:01 PM
1/4" hardboard or plywood. Which is stronger for drawer bottom? nelcatjar General Woodworking Discussion 5 05-20-2009 11:28 PM
make panels or use plywood? AnimalAdrian Joinery 2 03-28-2008 11:52 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome