Dave's Router

I have started building my router. The plan is that it will be a Kress (at least to start with) based 3-axis job with a cutting area of about 900mm x 600mm x ~220mm. I am attempting to over engineer so that it should be able to cope with aluminium, and be as flexible as possible.

The design involves two steppers and ballscrews on the X-axis so that I can unbolt some of the baseplate and put large objects (and flat objects on their side) into the router through a hole in the table.

The X and Y are on 20mm supported rail, and my plan is to use 20mm unsupported rail for the Z axis.

So far I have bought a scary amount of aluminium and other stuff and built some of it into a Y axis gantry - the photos are looking at the back of the Y axis
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Looks nice dave, keep the pics coming mate :)

Hi Dave. It looks like you are building the exact machine I would like to. I'm a fair way behind you, as I still trying to work out the terminology. Are you following a plan or is it your own scratch plan?

It is very much out of my head, the plan tends to change quite radically up until I actually start cutting metal - it is more fun this way. And as soon as I actually see a part I immediately think of a better way of doing the next step.

I am not entirely sure of the stiffness of the 50mm square Al beam with the supported rail on top, but it probably isn't bad. I think a bigger problem is fighting it turning into a parallelogram which is why I made the plate which is sitting on the top in the photo. If I started again I would have made one of the Square Al beams 5 inches longer so I could put a good triangular cross bracing plate overhanging the end.

Progress is going to be slow for a couple of weeks, as it is the Science Festival here in Cambridge and I have many many other things I have to build for it.

After a long interval - due to having many other things to build (most of which could have done with a CNC router - but the timings didn't work), I am starting to think about getting back to it.

I was going to use 20mm unsupported round steel rails for the Z axis. I was going to attach the rails to a plank of 12mm aluminium at each end. But just having received the rod and looked at it, it seems pretty rigid, the aluminium is going to involve more machining and use up space (I can probably get the router 20mm closer to the Y axis without it.

So I was wondering if I could get away with just clamping the router support at one end of the rails, and a stepper motor support at the other end, and just use the rails and a ballscrew for the axis, with no scaffolding. It is going to be a bit less stiff but not hideously so as the rails were unsupported anyway, possibly a bit more prone to twisting, but this isn't going to move the router very much, and the rails have got 4 well spread out bearings.

I haven't seen a design like this so was wondering if anyone else has done this and have I failed to think of a critical bending mode?

How you getting on with this one dave?

It has been very quiet for a while - I do a lot of science outreach, and science week is a killer for me, and the subsequent month has been catching up on the stuff I should have been doing in the runup to it.

I now have the Z axis bits, and I have just spent the weekend playing a sliding puzzle game with racks of dexion shelving to get an extra rack in so I can try and absorb some of the pile of junk that was accumulating on the floor of the workshop. But at some point this week I should be able to get back to it. I think I might have to bite the bullet and start on the x axis... Starting maching big expensive pieces of ali is a bit scary.

Have finally managed to do something to the router, and set up the base. Though quite how drilling 16 holes in the profile took most of a weekend, I am not sure...

At some time soon I am going to have to build some form of flying motor support cantilevered out over the rails... It seemed like a good idea at the time

I was doing really well, I have managed to mount the Y axis on slides and it all seems to work well.... Then I decided to try turning a ballnut around on its ballscrew...

I got it off ok onto the nice piece of tube Zapp sends with it. I think I then made the mistake of trying to put it back on the motor end not the floating end...

result balls all over the floor which I am never going to be able to find. I really hope I can get some more... Any suggestions?

Hi,

Have you managed to find them or replace them yet, if not let me know.