I want to DIY.. some questions please!

[Tenson]

Hi Ant,

I knew you got a CNC machine but only after reading about it on here as I haven't been reading DIYA much lately.When I read about your machine I thought 'oh, you too!'.

I'd love to go for a bigger machine but I just can't find the space. I moved a couple months ago and have a smaller workspace. But I did get a wife and a bigger listening room in exchange. I'm going for 2ftx4ft as sheets commonly come in that size, and also they fit in my car so I can collect myself. I thought about vertical mounting too, but I'm worried about the practicality of clamping work pieces in place, and I also want to make a dust/sound cover.

I got the spindle today actually :) I was unsure if I should get the 1.5Kw or 2.2Kw motor, but decided to go for 2.2Kw firstly because it was available from CNC4U at the same price as Chinese sellers, and also because I don't want to limit my cutting speed for the sake of £100.

So what are you doing for a water-pump, and does it need a radiator to cool the water? If so, I thought I might run the water through one of the alu extrusions.

By the way, Mr. ZappAutomation, please don't use the shredded paper for packing my floor is all messy now. At least get a paper shredder that makes long lines of it rather than flakes. :) Other than that thank very much for your great and fast service!

Fudge me, that's a big motor!! I hope my Z-axis can cope with 16mm rails and ballscrew.

[Tenson]

The 3020...notoriously shite in general and the principles used are barely suited to its own small frame

They are notorious for that, but it works superbly!!

[Jonathan]

I got the spindle today actually :) I was unsure if I should get the 1.5Kw or 2.2Kw motor, but decided to go for 2.2Kw firstly because it was available from CNC4U at the same price as Chinese sellers, and also because I don't want to limit my cutting speed for the sake of £100.

You made the right choice, but for the wrong reason! The main reason to get the 2.2KW spindle is that it takes ER20 collets which hold up to 13mm (i.e. 1/2") cutters, whereas the 1.5KW spindles are limited to ER11 which is only 7mm. I'm surprised CNC4YOU was cheaper than china - did that include the VFD?

So what are you doing for a water-pump, and does it need a radiator to cool the water? If so, I thought I might run the water through one of the alu extrusions.

Just get a generic brushless submersible pump, something like this one:

http://www.ebay.co.uk/itm/Water-Pump...ht_2757wt_1037

(seach around - you'll find cheaper ones)

No need for a radiator since if you have a decent volume of water the natural heat conduction to the atmosphere is sufficient. Just find a good size (20L ish) tank and ideally use de-ionised water with antifreeze.

By the way, Mr. ZappAutomation, please don't....

What did you get from Zapp?

Fudge me, that's a big motor!! I hope my Z-axis can cope with 16mm rails and ballscrew.

It will if done right - do post the drawing first.

[Tenson]

Mine has an ER16 clamping nut. I guess I can't use ER20 as the part the collet goes into (spindle shaft?) will be too small?

[Jonathan]

Mine has an ER16 clamping nut. I guess I can't use ER20 as the part the collet goes into (spindle shaft?) will be too small?

Yes the dimensions of the taper for ER20 are completely different so you'll have to use ER16, so upto 10mm:

http://www.ebay.co.uk/itm/FULL-ER16-...item231b785020

[Tenson]

Has anyone done this before?

Linear bearing - £6




Bearing taken out, and Ballnut put in:







Now it's not quite a perfect fit because the top of the nut is slightly ~0.5mm) taller than the top of the bracket housing. So one could either fit a thin sheet on top of the bracket, or trim the top off the nut if you can figure out how to do it. Or just account for it on the plate you are mounting.

Anyway, seems better than paying ~£35 for a ballnut housing? Isn't it?

[Lee Roberts]

Hi Tenson,

I see your cnc endeavours are coming along nicely!

I have toyed about a little with ball nut mounts myself using the "off the shelf" components, what I found with using the SMA units is the mounting holes for the Nut. If memory serves me right only two of the fixing holes could be used.

Your drive nut is properly one of if not the most critical part of an axis, personally I wouldn’t be happy with such a fixing, however I have seen machine’s up and running and only using the same two fixing points. I am guilty of being a perfectionist though with a little OCD topping to add to the flavour :)

In the end I decided to design my own drive nut mounts, I wasn’t able to machine them myself but another member on the forum was able to and did a great job for me. The price wasn’t a lot however they did stress that clamping was an issue due to the shape/design.

I have attached the finished picks for you to view, if you want the part details I am happy to post them for you.

.Me

[Tenson]

Thanks Lee! Four of the six screw holes can be used, so I thought that is enough. I also considered putting a bit of lock-tight around the nut before inserting it. Not too much, since it should come out again with a whack.

P.S. your mounts look like a super-charger!

[Jonathan]

Thanks Lee! Four of the six screw holes can be used, so I thought that is enough. I also considered putting a bit of lock-tight around the nut before inserting it. Not too much, since it should come out again with a whack.

I wouldn't put lock-tight round it. You'll need a bit of room for adjustment when you first fix everything together to ensure the nut can be set precisely concentric to the screw.

I've made a few ballnut mounts for myself and these for people on the forum:
\

I hope you're not intending to use those unsupported rails on this machine?

[Shinobiwan]

Hi Ant,

I knew you got a CNC machine but only after reading about it on here as I haven't been reading DIYA much lately.When I read about your machine I thought 'oh, you too!'.

Aye. I'd been looking longingly(as you do) at them for years but things fell into place the middle of last year and I suddenly found myself with a decent size workshop.

But I did get a wife and a bigger listening room in exchange.

Simon, it seems like we're in the twilight zone here. We've both bought a CNC, we build speakers and now we've both saddled ourselves with partners who moan about all the MDF dust we walk into the house or that the dinning room isn't an assembly area.

I'm going for 2ftx4ft as sheets commonly come in that size, and also they fit in my car so I can collect myself. I thought about vertical mounting too, but I'm worried about the practicality of clamping work pieces in place, and I also want to make a dust/sound cover.

You can build in a cover and have it vertical. Its more work in the design stage but can make for a really neat machine when space is an issue(when isn't it?). If I'd DIY'd I'd have likely done something very similar to this:

http://www.denfordata.com/pdfs/produ...cal-router.pdf

Very tidy package that would easily allow for a 4x4ft bed. All the crap falling into a pan at the bottom rather than all over the workpiece or into you rails etc. is another plus. Really there's not many downsides aside from increased build complexity and more awkward clamping. You could add vacuum bed later to solve the latter.

If your spending the sort of money I think you are then its worth considering.

I got the spindle today actually :) I was unsure if I should get the 1.5Kw or 2.2Kw motor, but decided to go for 2.2Kw firstly because it was available from CNC4U at the same price as Chinese sellers, and also because I don't want to limit my cutting speed for the sake of £100.

Good stuff but the ER16 collet might be a bit limiting. Can I ask why you choose that over the ER20? I looked around long and hard at cutters and most of the extra long series cutter are 12mm shank. These cutters allow thick(ie. 100mm) baffles to be safely machined.

So what are you doing for a water-pump, and does it need a radiator to cool the water? If so, I thought I might run the water through one of the alu extrusions.

Absolutely no need for a radiator/fan setup in this country, maybe the Sahara. I'm going for simple so that means a bucket with about 25ltrs of water, a dash of anti freeze and a regular submersible pump in the bottom. That's all you need and anything else is additional expense and not warranted. The only thing you need to watch out for is the pump head height capacity something like 3m is fine.

By the way, Mr. ZappAutomation, please don't use the shredded paper for packing my floor is all messy now. At least get a paper shredder that makes long lines of it rather than flakes. :) Other than that thank very much for your great and fast service!

Yep can't say I'm a fan either. No matter how carefully you try to remove things from the box that stuff still goes everywhere. I'm sure Gary is laughing whilst he's packing these things.