MFT Inspired Bench Design

[BrotherNov]

About a year ago I moved and lost my workbench in the process. I've been using a festool MFT3 ever since, and I've really come to like everything about it except the small size, and to a lesser extent the lack of weight/stout-ness. I really like the ability to clamp anything to it any where and any way necessary. I'm in the preliminary stages of planning my new bench and thought I'd ask you guys for some ideas. This is my 1st sketchup drawing ever, it's awful and only offered to give you an idea what I'm thinking about.

It's designed to hold 3 MFT3 tops within a 3 5/8" high (since that's the height of my vise) hard maple frame. Maple is 8/4, probably cleaned up to about 1 5/8". Overall length is 88", width is 46 5/8". The 2 flat cross members on the bottom are where I plan to attach a Noden adjust-a-bench leg set. I'll inlay a track on one of the long side to enable clamping to the sides.  I don't need the side rails to hold the track/saw; if I need this I'll still have my real MFT.  Anything inherently wrong with this design? It's awfully simple.  Think it will be heavy/stable enough? Any obvious design improvements?  If you think this is just a bad idea don't hesitate to say so. Thanks.

[attachimg=#]

 

[Sean KS]

I like the idea of using the MFT tops. I think 80/20 extrusions would make better rails than 8/4 hardwood. Easier assembly and pre-done t tracks. I'd like to see a more stable sub assembly so that the tops don't torque. Flatness may be an issue with this light of a design.

 

[BrotherNov]

Thanks for the reply, all good points which is why I asked for thoughts.  I too like the idea of using extrusions, and I've sen some fine examples o fit in use right here on the FOG.  My concern however is how to mount a very heavy vise to it, and I really like the idea but I also really like the thought of it being adjustable height.  My biggest concern with my plan is flatness.  Even if I get lucky enough to build it perfectly flat, I'm not convinced it will stay flat over time.  This was my inspiration:

 

[BrotherNov]

Maybe the best design is an 80/20 frame to hold the MFT plates on top of two hardwood stretchers that connect to the adjustable legs ......

 

[mhadler]

Thanks for the reply, all good points which is why I asked for thoughts.  I too like the idea of using extrusions, and I've sen some fine examples o fit in use right here on the FOG.  My concern however is how to mount a very heavy vise to it, and I really like the idea but I also really like the thought of it being adjustable height.  My biggest concern with my plan is flatness.  Even if I get lucky enough to build it perfectly flat, I'm not convinced it will stay flat over time.  This was my inspiration:

Is the one you got your inspiration from made from 80/20 extrusions?  Do you have the link to that project?  I'm interested in checking it out.

 

[BrotherNov]

The "inspiration" bench is in the picture a few posts before yours, and doesn't appear to use any 80/20.  What I'm after is a assembly and work table, and I suspect that the ability to adjust the height would come in quite handy sometimes.  I have zero experience with this 80/20 stuff, but it looks like something I need to learn about and incorporate into this bench and possibly a lot of other projects/jigs. 

As this will be my assembly table, dead-flat is a must.