Author Topic: Dominos and carcass joints  (Read 1716 times)

0 Members and 2 Guests are viewing this topic.

Offline mrFinpgh

  • Posts: 283
Dominos and carcass joints
« on: January 09, 2019, 10:18 PM »
Just a sanity check, as the DF500 is still very new to me.

I'm going to be building a freestanding cabinet that will be about 5' tall and 2' wide.  It's frameless, and will be veneer core plywood with butt joints.  All sides are exposed.  The sides of the carcass will sit between the top and bottom, and the back will be 3/4" thick and captive. There will be three shelves that are fixed in place. 

I was thinking about using Dominos for the entire assembly, but want to check with those who know : will that joint be sufficient for a tall cabinet or is the probability of racking going to be high?

Thanks,
Adam

Festool USA does not pre-approve the contents of this website nor endorse the application or use of any Festool product in any way other than in the manner described in the Festool Instruction Manual. To reduce the risk of serious injury and/or damage to your Festool product, always read, understand and follow all warnings and instructions in your Festool product's Instruction Manual. Although Festool strives for accuracy in the website material, the website may contain inaccuracies. Festool makes no representations about the accuracy, reliability, completeness or timeliness of the material on this website or about the results to be obtained from using the website. Festool and its affiliates cannot be responsible for improper postings or your reliance on the website's material. Your use of any material contained on this website is entirely at your own risk. The content contained on this site is provided for informational purposes only and does not constitute professional advice.


Offline ChuckM

  • Posts: 925
Re: Dominos and carcass joints
« Reply #1 on: January 09, 2019, 10:36 PM »
No racking of any kind as long as the back is properly done. How are you installing the back: nailing/screwing/gluing, and rabbeting or grooving?

Offline Birdhunter

  • Posts: 2481
  • Woodworker, Sportsman, Retired
Re: Dominos and carcass joints
« Reply #2 on: January 10, 2019, 06:07 AM »
Agree with ChuckM re racking, but curious as to your plan for applying edging to the  exposed plywood.
Birdhunter

Offline mrFinpgh

  • Posts: 283
Re: Dominos and carcass joints
« Reply #3 on: January 10, 2019, 06:25 PM »
I think I could domino the back into the sides, top, and bottom of the carcass.  Assuming I got the back square, that would be a lot of interconnecting parts.

When I do solid wood on plywood, it's usually sufficient for me to just apply via a butt joint - I cut the edging around 7/8 and use old brown glue to attach.  I've never tried the special bits that make the edge slightly concave.

Thanks,
Adam

Offline Birdhunter

  • Posts: 2481
  • Woodworker, Sportsman, Retired
Re: Dominos and carcass joints
« Reply #4 on: January 10, 2019, 08:48 PM »
I’ve never seen anything on the bits you mention.

I use a thin strip of hardwood about 1/8” thick, apply Titebond III, and “clamp” with blue tape.
Birdhunter

Offline Jcwoodshop

  • Posts: 26
Re: Dominos and carcass joints
« Reply #5 on: January 15, 2019, 08:08 AM »
Your approach of fastening the 3/4″ back panel to the top, bottom and sides of the cabinet, using dominos and glue will provide a sufficient joint. You may wish to apply edge banding to the back panel if you believe the unfinished plywood edges would detract from the appearance of your cabinet.

One caution with your approach is that the 5’ long plywood sides may experience enough warping that aligning the dominos with their slots will be a bit time consuming and frustrating.
 
Another approach you may wish to consider is to cut a rabbet (say 3/8″ wide by 3/4″ deep) along the rear edges of the top, bottom, and sides; and insert the back panel into the rabbeted members. There are many different methods to cut this joint, your approach will depend on your abilities and/or the equipment available.

Offline Straightlines

  • Posts: 22
Re: Dominos and carcass joints
« Reply #6 on: January 25, 2019, 03:47 PM »
Your approach of fastening the 3/4″ back panel to the top, bottom and sides of the cabinet, using dominos and glue will provide a sufficient joint. You may wish to apply edge banding to the back panel if you believe the unfinished plywood edges would detract from the appearance of your cabinet.

One caution with your approach is that the 5’ long plywood sides may experience enough warping that aligning the dominos with their slots will be a bit time consuming and frustrating.
 
Another approach you may wish to consider is to cut a rabbet (say 3/8″ wide by 3/4″ deep) along the rear edges of the top, bottom, and sides; and insert the back panel into the rabbeted members. There are many different methods to cut this joint, your approach will depend on your abilities and/or the equipment available.

This and a captive dado are more traditional means of attaching the back, and since the top will be covering the edge of the rear panel edge, you could use 1/2” plywood instead and save on weight without any practical compromise in strength.

Offline jobsworth

  • Posts: 5553
  • Festool Baby.....
Re: Dominos and carcass joints
« Reply #7 on: January 25, 2019, 05:03 PM »
Plan on useing 5 dominos per joint once its glued and clamped it should be plenty strong. The back will prevent racking.

Offline escan

  • Posts: 67
Re: Dominos and carcass joints
« Reply #8 on: January 26, 2019, 09:54 AM »
You may want to dry fit before glueing to make sure all those slots line up.

Offline jobsworth

  • Posts: 5553
  • Festool Baby.....
Re: Dominos and carcass joints
« Reply #9 on: January 26, 2019, 10:44 AM »
Oh yea, Be sure to mark the domino face.

Offline mrFinpgh

  • Posts: 283
Re: Dominos and carcass joints
« Reply #10 on: January 26, 2019, 12:08 PM »
Thanks, all.  As it happens, the project has evolved into something entirely different because the 2' wide doors were going to be a bit awkward to open.  The new design is more of a barrister style bookcase, which should be easier to control for leverage points. 

Still, the above advice is valuable.  I've only used the domino to line up some joints on some frameless cabinets, and it worked very well for that.

Thanks,
Adam