3D Printed Extension Brackets for MFT/3

[Bob D.]

I found an extension bracket on thingiverse for the MFT/3.

Printing out the second one now, first one looks good and has a nice fit.
It's 2 hours, 34 minutes printing time for each bracket.

I think I will use these to the right to add some offcut support. The brackets
are only 4-5/8" wide but should support a 6 inch wide piece of 3/4" material.
The bracket has 3 holes for using screws to attach the top. Only thing missing
is a spot for a screw to lock the bracket in position on the side rail of the MFT.

I haven't tried adding that as yet. I figured I'd print the file out first and see
how I liked it before I butchered it with my half-a$$ed CAD jockey skills.

Is it possible to import .STL files into Sketchup for editing?

Here's a link to the thingiverse page for anyone interested.
https://www.thingiverse.com/thing:3491303

 

[squall_line]

Based on the outline and the use image, they slot in from the side of the table, rather than just dropping on from the top, is that correct?

 

[Bob D.]

Yes, you can't lift them off. They have to slide off on the ends.

They are very snug but not a tight fit, just loose enough to slide
easily but they don't rattle or flop around.

 

[luma]

Is it possible to import .STL files into Sketchup for editing?

SU does STL import natively and can kinda-handle solid modeling if the model you import is, in fact, solid.  Good news, this one is!

Only thing missing is a spot for a screw to lock the bracket in position on the side rail of the MFT.

Maybe something like this?

If so, here's a zip file with that model in SketchUp format and also an exported STL ready to print.

 

[Bob D.]

Yes, that's what it's missing in my opinion. Thank you.

I will print it out and see how it looks.

 

[squall_line]

Only thing missing is a spot for a screw to lock the bracket in position on the side rail of the MFT.

Maybe something like this?

How would a bolt in that new location connect to the MFT Rail? Are you going to drill a hole in the MFT Rail?

View attachment 1

It's more about using pressure to wedge the extension in place by pressing a screw head against the rail.  The concern then would be denting the rail or pulling the top of the extension out if you tightened it too far.

 

[Bob D.]

Thanks for your thoughts everyone.

I printed with PLA and it is quite rigid. There is no flex and yes it's not a very robust part but it's not meant to be sat on.

I printed two of them and had a scrap of 3/4 ply that measures 5-1/2 x 27 inches so I secured that with some screws. You cannot lift it off the rail since the bottom is captured in the t-slot.

My thought on the hole that Luma added was to use a socket head cap screw with a nut locked on flush with the end of the thread. This would provide a large surface to prevent denting the rail. IT shouldn't take much pressure to lock it in place. The location of the hole Luma added I think will work but what I want to add is a pocket for a 1/4" hex nut. Then use a full threaded 1/4" SHCS which I will be able to turn using a hex wrench. Other possibility is to print a small knob to fit the hex head of a 1/4" screw and just reach in with two fingers and snug the locking screw against the rail.

I'll look at it some more tomorrow. I'm working on getting dust collection setup on the CNC so will be in the basement shop tomorrow. It's been too cold the last few days to work out in the garage shop. I do have heat out there but I don't want to heat all that space for something I can do in the basement shop.