F***ed up a dado... how to fix it? - Woodworking Talk - Woodworkers Forum
 
Thread Tools Display Modes
post #1 of 15 Old 12-06-2011, 12:34 AM Thread Starter
Senior Member
 
Thadius856's Avatar
 
Join Date: Nov 2011
Posts: 111
View Thadius856's Photo Album My Photos
F***ed up a dado... how to fix it?

First, a little back story... or skip to the bold part...

So, two mornings ago I set about cutting dadoes. I stacked my bookcase sides up into two piles, aligned the bottom ends, marked off my measurements on both piles from the bottom edge, and then used a square to mark all the dado edges. Lesson one... stack in one giant pile and mark, use stop jigs, or go home.

To double check my measurements, I had the carpenter measure my lines and read them aloud. Everything matches within 1/32", great. I made my cuts and was done. Right?

Wrong. Dead $%(*ing wrong.

See, even though the carpenter and I have synced down to even using the same brand of tape, we apparently think and speak in different units... his from a career of framing and concrete forms and mine from a mechanical drafting perspective. While he was calling "two three and five" and meaning 2'3-5/16", I was understanding 2'3-5/32", though if I was calling that measurement I'd call "two seven and five thirty-seconds" from my military training. I'm sure you see the problem already, and thus lesson two.

My dadoes just don't line up. The shelf dadoes are within 1/8" over a 23" shelf span, so probably not visible and thus acceptable, even with a 3" face frame. Except for one dado... and it's a solid quarter inch low. My choices were to split the difference on all of the shelves, shortening half of the side pieces at the bottom and the other half of the side pieces at the top (they'd still be off about half as much), but that would require crosscutting all the sides and backs again, so I'd have to retool the radial twice and the table saw once. No thanks. So, I widened the dado up 1/4" and accepted the imperfection in alignment. However, that opened up the bottom of the dado.

So now I have four bookcases with a dado which is 11" long, 1/4" too wide, and the open end is going to fall on the bottom (no support on the underside of the shelf). I've already resigned myself to the fact that I'll probably have to cover the underside of the shelves with a decorative moulding. What can I do to give structural support to the shelf that could be hidden under quart round, shoe molding, etc?

For reference, this is in 7-ply undersize 3/4" red oak ply with the dado against the veneer grain. The backside of the side pieces and backs will never be seen once installed.

Last edited by Thadius856; 12-06-2011 at 12:39 AM.
Thadius856 is offline  
Sponsored Links
Advertisement
 
post #2 of 15 Old 12-06-2011, 12:50 AM
Senior Member
 
Join Date: Nov 2011
Location: Queensbury, NY
Posts: 272
View Upstate's Photo Album My Photos
Not sure if I understand completely, but can you widen all the dados and use thicker shelves? So instead of 1/2" shelves, you'd use 3/4" material? I think I read you were about 1/4 off, right?
Upstate is offline  
post #3 of 15 Old 12-06-2011, 01:42 AM Thread Starter
Senior Member
 
Thadius856's Avatar
 
Join Date: Nov 2011
Posts: 111
View Thadius856's Photo Album My Photos
Already using undersized 3/4". Shelves were glued up last night.
Thadius856 is offline  
Sponsored Links
Advertisement
 
post #4 of 15 Old 12-06-2011, 04:57 AM
Old School
 
cabinetman's Avatar
 
Join Date: Jul 2007
Location: So. Florida
Posts: 24,027
View cabinetman's Photo Album My Photos
Quote:
Originally Posted by Thadius856 View Post
Already using undersized 3/4". Shelves were glued up last night.
I would just use a small 1/4 round or cove moulding and glue in place. Use mechanical fasteners if you can...pin nails for the moulding and shelves. Small holes can always be dressed up.

Since the gap is at the underside of the dado, slip in a shim the depth of the dado just to maintain support. Gluing on the add on will also help with support. I would use the mouldings on all the shelves so it looks purposeful.








.
cabinetman is offline  
post #5 of 15 Old 12-06-2011, 05:55 AM
Really underground garage
 
Join Date: Aug 2010
Location: mnts of Va
Posts: 2,552
View BWSmith's Photo Album My Photos
Thicker shelves as has been mentioned.....but,as resaw add-ons that are only on ends.Kinda hard to describe,we've done a few highend libray's like this from the get-go.

The resaw pcs of solid/matching species are the same width as shelf,glued to shelf bttm.Usually 3 or so inches from end of shelf.....and reluctant to even suggest a thickness but in the 1/2" range.The "trick" part is their profile.Its a flat...then they're cut on a Cyma(the hard way).

Can be done with contrasting woods,but it draws attention to a detail better left un-noticed,IMO.These are the tiny details that seperate the chaf from the wheat so to speak.......You really have to pay attention to finished pce to even see them.Its so easy to "add" elements(Martha) that jump out at you......Its the stuff that you don't see or really have to study that keeps me going back to antiques,and in general looking to the past for answers.Best,BW

Those who say it cannot be done shouldn't interrupt the people doing it.
BWSmith is offline  
post #6 of 15 Old 12-06-2011, 06:39 AM
Senior Member
 
Join Date: May 2009
Location: northern illinois
Posts: 845
View mikeswoods's Photo Album My Photos
Change the way that you two take measurements----use inches only---no more math conversions in your head--
mikeswoods is offline  
post #7 of 15 Old 12-06-2011, 06:53 AM
Senior Member
 
Join Date: Jul 2008
Location: Florida Panhandle
Posts: 12,477
View GeorgeC's Photo Album My Photos
Quote:
Originally Posted by cabinetman View Post
I would just use a small 1/4 round or cove moulding and glue in place. Use mechanical fasteners if you can...pin nails for the moulding and shelves. Small holes can always be dressed up.

Since the gap is at the underside of the dado, slip in a shim the depth of the dado just to maintain support. Gluing on the add on will also help with support. I would use the mouldings on all the shelves so it looks purposeful.











.
This seems very simple to do and it will solve your problem.

George
GeorgeC is online now  
post #8 of 15 Old 12-06-2011, 06:58 AM
Old School
 
cabinetman's Avatar
 
Join Date: Jul 2007
Location: So. Florida
Posts: 24,027
View cabinetman's Photo Album My Photos
Since you've glued and installed the shelves already, there's another method you could do. Cut 1/4" (or thicker) plywood the depth of the shelves, and the length to fit in between the ends. The front edge can be nosed with a moulding for the extra thickness. There wouldn't be any add on moulding showing.








.
cabinetman is offline  
post #9 of 15 Old 12-06-2011, 07:32 AM Thread Starter
Senior Member
 
Thadius856's Avatar
 
Join Date: Nov 2011
Posts: 111
View Thadius856's Photo Album My Photos
Shelves are cut to dimension, less a 1-7/16 wide piece of quartersawn oak on the front. They are not glued in place yet (ran out of 220 grit).
Thadius856 is offline  
post #10 of 15 Old 12-12-2011, 11:46 PM
Senior Member
 
Join Date: Sep 2011
Posts: 576
View Midlandbob's Photo Album My Photos
Have you considered filling in any offending dado preserving the grain direction. Then recut the dado.
If the "patch" is above high shelves and below low shelves, it might be acceptable enough not to need the trim.
Or put the trim on all the shelves?
Midlandbob is offline  
post #11 of 15 Old 12-13-2011, 11:06 AM Thread Starter
Senior Member
 
Thadius856's Avatar
 
Join Date: Nov 2011
Posts: 111
View Thadius856's Photo Album My Photos
Looks like I'll be trimming all the shelves. If it wasn't $150 in plywood, I'd consider redoing them.
Thadius856 is offline  
post #12 of 15 Old 12-17-2011, 12:20 AM
Member
 
Join Date: Dec 2011
Location: winnipeg..ish
Posts: 31
View andrewscevich's Photo Album My Photos
forgive me if i misunderstand... but... couldn't you just rip a strip of oak on a table saw on a bevel... then tap it under the offending shelves as a long long shim. glue it in place, then trim off excess flush with inside walls - i like to use a hand-plane iron by itself for flush trimming....if you fit the strip/shim in tight enough, you wouldn't even need to cover with a moulding - it would take stain just as the sides do. - does this make sense or do i sound like a fool?

Love the brotherhood. Fear God. Honor the Emperor
andrewscevich is offline  
post #13 of 15 Old 12-17-2011, 12:42 AM
John
 
Join Date: Mar 2010
Location: La Crosse, Kansas
Posts: 3,028
View jschaben's Photo Album My Photos
Hi Thad - You're not likely to make that mistake again. But, as a suggestion for future reference. Initially cut the stock for the sides slightly wider than twice the final width. Then route your dados and then rip to final size. Dados will always match up.

John

If I strive for perfection, I can generally achieve good'nuff, If I strive for good'nuff, I generally achieve firewood
jschaben is offline  
post #14 of 15 Old 12-17-2011, 01:04 AM
where's my table saw?
 
woodnthings's Avatar
 
Join Date: Jan 2009
Location: SE, Michigan
Posts: 27,624
View woodnthings's Photo Album My Photos
Quote:
Originally Posted by Thadius856 View Post
Already using undersized 3/4". Shelves were glued up last night.
Quote:
Originally Posted by Thadius856 View Post
Shelves are cut to dimension, less a 1-7/16 wide piece of quartersawn oak on the front. They are not glued in place yet (ran out of 220 grit).
Quote:
Originally Posted by Thadius856 View Post
Looks like I'll be trimming all the shelves. If it wasn't $150 in plywood, I'd consider redoing them.
Which is it, "glued up" the shelves or "not glued" in place?

Why would you trim the shelves unless the dados are undersized?

Quote:
So, two mornings ago I set about cutting dadoes. I stacked my bookcase sides up into two piles, aligned the bottom ends, marked off my measurements on both piles from the bottom edge, and then used a square to mark all the dado edges.

NOthin' wrong with this procedure. If you mark up one as a "master" then transfer all the marks down with a square, one pile or two plies it won't matter. One pile is best since the transfer is once rather than twice, but a good master will make them the same. Stops will work equally well, right or wrong they will all be the same from one end.

Quote:
So now I have four bookcases (sides) with a dado which is 11" long, 1/4" too wide, and the open end is going to fall on the bottom (no support on the underside of the shelf). I've already resigned myself to the fact that I'll probably have to cover the underside of the shelves with a decorative moulding. What can I do to give structural support to the shelf that could be hidden under quart round, shoe molding, etc?

As suggested make a filler piece to close the difference and locate it in the least visible place, under the lower shelves and on top of the higher shelves.

Aside from remaking the sides with new stock, there ain't no good way to make a wide dado more narrow than fill it. Unfortunately, the grain "should" run the same lengthwise, across the dado, but that probably won't happen.

You "could" fill all the dados with length grain pieces and resaw them all, but that probably won't happen either.

Sometimes a "f" up is just that and you either live with and repair it as best as possible, or if you are like me you will just bite the bullet and make new sides.


Remember, measure 2x, cut 1X or in my case measure 1X cut 1X cut 1X again for good measure. bill
BTW I would never trust anyone else's measurement to be the same as mine, unless we are makin' studs for a frame wall.... 7' - 11 1/8" and a fuzz....

The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)

Last edited by woodnthings; 12-17-2011 at 01:13 AM.
woodnthings is online now  
post #15 of 15 Old 12-17-2011, 01:23 AM Thread Starter
Senior Member
 
Thadius856's Avatar
 
Join Date: Nov 2011
Posts: 111
View Thadius856's Photo Album My Photos
Quote:
Originally Posted by woodnthings View Post
Which is it, "glued up" the shelves or "not glued" in place?

Why would you trim the shelves unless the dados are undersized?
"Glued up" the shelves as I'm glued the solid face onto the plywood shelves to hide the plies. Thats the only assembly that's been done... the carcasses have not been glued together. (yet).

And "trim the shelves" as in trim them out... or in other words add trim underneath each shelf where it meets the carcass wall to hide the screwup.

Clearer now?

Last edited by Thadius856; 12-17-2011 at 01:26 AM.
Thadius856 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
what dado set to use...? douglasrome Power Tools & Machinery 16 01-29-2011 10:02 AM
Dado set ? Rick C. General Woodworking Discussion 18 12-29-2010 12:47 PM
First dado set. dribron Joinery 7 12-29-2010 12:10 AM
Need help with my dado set Gene Howe General Woodworking Discussion 4 11-12-2009 05:45 PM
Dado set jodiemeglio Power Tools & Machinery 1 05-07-2007 11:19 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