1.7*0.74*0.4m Mill / Router building...

[Jonathan]

I'd be more worried about the effect of vibration on the VFD.

Yes I thought that too. I mounted it using those foam sticky pad things which, thinking about it, should damp the vibrations a little. Another issue is dust getting into the VFD which would reduce the efficiency of the heatsink.

[FatFreddie]

Carbon fibre dust is conductive...

[FatFreddie]

Runout isn't great - 0.05mm ish.

What were they quoting for runout? I was looking at some that were quoting ten times better than that - just wondering how reliable the claims are.

[Jonathan]

Carbon fibre dust is conductive...

True, and texalium which I'll machine at some point is going to be even worse. Apparently carbon fiber dust is worse than asbestos, so I will allways use the dust extraction with it anyway.

[Jonathan]

What were they quoting for runout? I was looking at some that were quoting ten times better than that - just wondering how reliable the claims are.

Yes mine was indeed quoted at ten times better than than.


I've decided to make a welded steel frame for my router. This is my initial design:



I will probably add a few more triangles to that, however I'd like to keep the front of the machine open.

In that drawing I've discarded the tall gantry sides and replaced it with a bit of 100x60x3.6mm steel box section, so now the 'gantry' is only 100mm tall, not several hundered mm. This should help with the stiffness.

Also I am intending to have the existing bed fit inside the frame and attach it to the 6 vertical pieces with a series of holes which will allow the bed to be raised and lowered depending on the size of the job. Most of the time I will have it as close as it will go to the gantry, giving only 100mm (ish) z-travel. I've not yet needed more than this so I think it's a good way of stiffening up the machine without compromising on working volume. It'll also gain a good bit of travel on the Y axis.

[Jonathan]

looking good jon,this ones allways been a favourite of mine on the tube,very simular,works well.
http://www.youtube.com/watch?v=hAS3GRE61jY

That one does look good, except for the position of the X-axis ballnuts which will cause uneven loading on the X linear bearings.

I'm not sure that the 100x60x3.6mm steel box section I've used on the sides is going to be sufficient. That cross section is weak with forces parallel to the Y axis. I may get some aluminium profile to fit there. Chip, can you remind me where you got yours please? What you used for your gantry sides looks about the right size.

[Jonathan]

Quick update. I've ordered the steel for the frame and it should be ready Thursday or Friday. I've now started dismantling the machine ready for the conversion. I'll post more here with pictures as it happens...

heres the place jon,http://www.aluminium-profile.co.uk/ i think it was 90mmx45mm i used.

Thanks for the link. I'm tempted to use it for the sides, but if I did I can't weld it. I think I will weld some steel sheet on to the ends of the box section to strengthen it.

[Jonathan]

I got the steel on Wednesday. Adey Steel were very organised and helpful. They cut the steel to the lengths I specified. They did accidently not give the offcuts from cutting my steel that I requested, so I went back and got it plus they gave me some box section free of charge along with some 6mm plate to practice welding with!! I'll use some of the extra box section to make the frame stronger if required..

Since then I have used my metal bandsaw to cut the box section - it's cutting very close to square now. I'm currently drilling lots of holes in it which will be used to support the bed at different heights. I intend to motorise the bed, effectively making it an F axis, to minimise the overhang of the Z-axis for each job.

I've ordered the ballscrews for X and Y (RM2510 and RM1610) - the tracking says they should arrive in one week, so my aim is to have the frame done by then.

The basic shape of the frame is going to be the same as in post #113, with a few extra pieces to strengthen it. The front is 'missing' to allow the Z axis to protrude past it at the end of the travel. I've used 50mm and 60mm, 3mm thick box section and 120x60mm, 3.6mm rectangular in places where I wanted a bit more strength.

Here's a couple of photos:

[Jonathan]

Slow progress with the frame, I've been getting distracted making other bits - such as spindle mounts:



I've drilled most of the holes required in the frame, just got a few more to work out. I think it's best to drill them all using the milling machine ... except I can't really do that with the holes for the linear rails as I'm not confident I will be able to weld the frame parallel enough. I'm using the bed support rails to clamp the three upright pieces of the frame in place to weld, not sure about the rest...maybe some sash cramps:

[Jonathan]

i,ll have to have one of those spindle mounts off you soon,when i get round to changing my z plates.

Excellent ... I'm hoping I'll be able to mill them on the router when it's done as that should be quicker, or at least easier, than milling them. I would still bore the 80mm hole on the lathe. I will also round off the two corners that look a bit thin.





I've just drilled fixing holes in the 100x60 box section for the bed jacking screw mounts. I just need to drill some more holes for the X axis ballscrew mounts and chamfer quite a few of the ends then the main frame is ready to weld.