Author Topic: What practical accuracy is acceptable on MFT/3 for frameless cabinets?  (Read 1832 times)

0 Members and 1 Guest are viewing this topic.

Offline Kodi Crescent

  • Posts: 711
I'm working to square my MFT/3 to crosscut parts for frameless cabinets.  Using the 4 cut method, I end up with the error being 0.01 inches per cut from square.  This is over a 40 cm cut.  Is this level of accuracy acceptable for frameless construction?

(Units added per other comment).
« Last Edit: September 16, 2018, 09:22 AM by Kodi Crescent »

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.


Online cpw

  • Posts: 80
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #1 on: September 15, 2018, 09:53 PM »
I'm working to square my MFT/3 to crosscut parts for frameless cabinets.  Using the 4 cut method, I end up with the error being 0.01 per cut from square.  This is over a 40 cm cut.  Is this level of accuracy acceptable for frameless construction?
.01 what?  If you're saying .01cm/40cm; I think the largest cabinet you are likely to make is 96 inches or 243cm which is about 6 times 40; or .06cm ~= .023in or under 1/32.  You have about 2mm of adjustment in euro hinges, so I think you should be within tolerances.

Caveat: I've built a house full of cabinets, but am not a professional.

Offline lwoirhaye

  • Posts: 178
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #2 on: September 15, 2018, 10:23 PM »
I think it's probably okay for many framless builds.  Make a sample cabinet with an inset slab door and see how the reveals look.   Once you start stacking frameless boxes things can get weird if the setup isn't dialed in really well, but single rows under counters and things like that are more forgiving.

Offline jobsworth

  • Posts: 5242
  • Does Anyone Know What Time It Is?
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #3 on: September 15, 2018, 11:15 PM »
Wood will move more than that, your walls will out more than that and thats why they make shims

Offline Cheese

  • Posts: 4953

Offline Kodi Crescent

  • Posts: 711
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #5 on: September 16, 2018, 06:16 PM »
I was able to get it down to 0.0055" over 335 mm.  That's about the same difference in offcuts for the crosscut sled on my table saw.

If I calculated the angle correctly, it's 0.024 degrees (?).  I'm assuming this means when I make a square cut on the MFT one side will be 89.976 degrees, while the other is 90.024 degrees.  Is this logic correct?

« Last Edit: September 16, 2018, 06:41 PM by Kodi Crescent »

Offline Cheese

  • Posts: 4953
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #6 on: September 17, 2018, 10:14 AM »
I was able to get it down to 0.0055" over 335 mm.  That's about the same difference in offcuts for the crosscut sled on my table saw.

If I calculated the angle correctly, it's 0.024 degrees (?).  I'm assuming this means when I make a square cut on the MFT one side will be 89.976 degrees, while the other is 90.024 degrees.  Is this logic correct?

Both your calculation and your logic is correct.  [smile]

That's basically 1 1/2 minutes of angle...pretty small. I wonder how long that will last on an MFT?  It'd be interesting to do another check after you've used the MFT for a while.

Offline fshanno

  • Posts: 960
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #7 on: September 18, 2018, 12:53 AM »
The accuracy you've described is about what I get.  It will work fine for frameless casework.  I've cut up hundreds of sheets of plywood for cases that go together well.

I'll offer a suggestion.  Unless you have access to outstandingly flat and stable plywood, I wouldn't go frameless for wall cabinets.

The narrower sides tops and bottoms are more susceptible to slight bowing.  You can take the bow out of the back edges of the sides top and bottom with stretchers or a solid back.  But since the front can't have stretchers the bow may still be there on the front edges.  You can't put stretchers across the front, obviously, and nobody goes with fixed shelves any more.  The face frame will remove the bow or completely hide it.  It also makes the wall cabinets a little stronger which isn't a bad thing.

Also you don't really lose storage space in wall cabinets with face frames.  You can go with full overlay doors and achieve the same 1/8" overlay just like your frameless base cabinets. 
The one thing we learn from history is that we never learn from history.

Offline waho6o9

  • Posts: 1385
    • Garage Door Handyman.com
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #8 on: September 18, 2018, 09:57 AM »
" You can't put stretchers across the front, obviously, and nobody goes with fixed shelves any more."

I was going to suggest a middle fixed shelf with a 3/4" back and you're good to go. And if you use Blum

soft closing hinges you'll need a positive stop anyways and the fixed middle shelf will do that.

Offline Michael Kellough

  • Posts: 3536
Re: What practical accuracy is acceptable on MFT/3 for frameless cabinets?
« Reply #9 on: September 18, 2018, 12:32 PM »
I'm working to square my MFT/3 to crosscut parts for frameless cabinets.  Using the 4 cut method, I end up with the error being 0.01 inches per cut from square.  This is over a 40 cm cut.  Is this level of accuracy acceptable for frameless construction?

(Units added per other comment).

1/100th off over 15-3/4” is pretty good and is acceptable for parts that size (probably a lot better than most places achieve) but if you working on setting up your equipment as best you can then a goal of .01” over 40 inches would be much better for the long term. If you do achieve than then you’re biggest problem in getting cuts that are that accurate will be keeping the edges of the material free of dust big enough to misalign the material to the sled fence.