Well here goes... Aluminium frame router design

[CharlieRam]

Cheers everyone, what about the ends of the X supports. Could there be an issue of strength where i have cut into the box section, I am hoping it wont matter so much at the end of the travel as the carriages will still actually be on full box section, only by about 25mm though. I could glue a 5mm steel plate under those areas.
One last thing for now, will 4mm thick steel be strong enough to tap through for bolting the rails?
Cheers, Charlie

[Tinkerer]

Hi RouterCNC

I thought I would go to the effort and recognise your outstanding work on the stiffness calculator. It has removed guesswork on my part and/or countless days of research. Thank you. I had your v7, but see it has been improved with v8! Again many thanks.

Richard

[CharlieRam]

Well, after a long break....well more finishing other jobs :-)
Design 14 is ready for your scrutiny, pretty much everything is designed to size apart from bolts. just working out a BOM at the minute to work out the costs. The bed is part welded and part bolted but I am wondering if I could bolt the whole lot and still keep a strong structure? what are your thoughts.
I have included the full sketchup model so you can have a good look if you want, all components can be ungrouped and moved along there respective axis so have fun!
Thanks, Lee

[CharlieRam]

Hi guys, what is your opinion about swapping the angled box section for 5mm thick steel plate, will it significantly alter the strength, have a look at what I mean below. All corner braces would be the same as the white one if it is ok.
Also I am considering having the frame bolted together rather than welding other than the flanges that are welded to the upright pillars suspending the X axis, if it is all bolted I would be able to dismantle to make any mods or changes but in your opinion would it still be rigid enough.
I've just ordered my Rage 3 saw :-) and when I get paid in 4 days the steel will be ordered but it comes in at just under £200 and if I can swap some of the box for flat I could save about £40. every little helps!
Thanks, Charlie.

[toomast]

I would not use steel flat-bar in there. I understand that it is easier to build it like that but I doubt you gain much with this design. In order for diagonals to work effectively other ends must be connected as well. So I would advise box section for diagonals + connect the other ends with box section too. For diagonals you can use smaller profile. If you want to keep adjustment option then you must weld the end-plates and use bolts.
I'm currently redesigning my machines frame - adding connections for the other end of the diagonals and making profile smaller but thicker.

[Boyan Silyavski]

I would use no diagonals at all as the structure seems right to me. However i will use 10mm thick plate for the bolt on connections. That should do it

[CharlieRam]

Thanks for the quick replies guys.

I would use no diagonals at all as the structure seems right to me. However i will use 10mm thick plate for the bolt on connections. That should do it

Hi Boyan, when you say no diagonals, you mean to remove all angled box sections? and then swap my 5mm plate for 10mm on the existing bolt plates, the reason I chose 5mm was because it would be easier to weld to the 4mm box section (I think!)
Cheers, Charlie

[Boyan Silyavski]

Thanks for the quick replies guys.

Hi Boyan, when you say no diagonals, you mean to remove all angled box sections? and then swap my 5mm plate for 10mm on the existing bolt plates, the reason I chose 5mm was because it would be easier to weld to the 4mm box section (I think!)
Cheers, Charlie

Yes,
and if you do the small effort of designing and welding additional bottom plates where the threads will go, i am sure about that.

There is no problem welding 10mm plate to 4mm box section, on the contrary, the weld when properly done will make things stronger


Anyway, you could just buy 6m flat 10mm thick bar and cut it to many pieces with the Rage.

[CharlieRam]

I have been looking at the X drive and have modeled up what I have in mind, I was originally thinking twin motors but I didn't want to tie up a 4th drive, so if I go for the following method would the belt length cause too much issue (I have worked out the belt length and the nearest standard length from Zapp is 1895mm) and also would a nema 23 do it or should I go upto a nema34. In the first image the belt is housed in a 50x25 3mm thich channel, in the second I have moved it up to show the belt run. This gives me about 2mm inside the box section in all directions clearance. Should I expect more belt sag or whip , I am hoping if they are tensioned OK then it will be sufficient but as I have no experience of using belt drives I have no Idea!
Cheers, Charlie

[njhussey]

I've got a Nema 34 on my X axis, in theory a Nema 23 would do it but I wanted to be sure....