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Hello all,

I have finished my first CNC and had a couple questions about spindles. I am currently using a Dewalt DW660 (30K RPM) to cut wood and some plastic. It seems to work just fine, except there are a couple things I would like to improve and I suspect it may be a good idea to try another cutting tool. I have seen all kinds of spindles on Ebay or various sites but I am not sure if they are overkill for what I am looking to do. Would anyone mind weighing in with their experienced opinion?

Requirements/Questions:
1. Primarily used to cut wood and plastic.
2. Cutting Aluminium would be a nice benefit, but not essential
3. Collet size of ~<=1/8" at minimum. Some traditional wood routers have collets of 1/4", this is OK, but I need the ability to cut with smaller endmills. Do they make small endmills with such a large shaft?
4. Variable speed. I have a few endmills that have become dark after use. I assume it is getting too hot probably from spinning it at such a fast rpm.
5. Is it possible to get a quieter spindle? Routers are pretty loud, any chance a better spindle is more quiet?
6. Should I be looking at something that needs a VFD or water cooling?

Thanks!

[aarggh]

Spindles are simply far superior to consumer wood routers when it comes to CNC machining. The normal wood routers on the market have terrible runout, low life bearings compared to better tools, and are simply not designed for the duty cycles of cnc machines that can be running 8 out of every 24 hours for weeks at a time.

Spindles are far quieter and more accurate, and will last much longer than routers. I prefer water cooled spindles as you don't have any air circulation or fans to worry about clogging up with dust. Some prefer air cooled, but unless you have a very good dust extraction system setup, you'll be sucking and blowing dust and waste through the air path.

I have several of the cheap Chinese ones, in a variety of power ratings, and generally tend to use the 1.5kW one for most things. Depending on your wallet you could get a good Hitachi VFD to match the commonly avaliable spindle, or just a VFD/Spindle combo of the Huanyaun (or something like that anyway) variety. 'Despite all the bleating from people here about crappy Chinese stuff, I haven't actually seen many posts at all from people that actually had experienced failure of the cheap Chinese VFD's/spindles. The last 2.2kW VFD/spindle I bought off ebay cost me around $380 inc shipping, which I though was pretty damn cheap! Certainly far cheaper than some wood routers I've bought.

I'm more than happy with mine. I use it for wood/plastics/aluminium routinely.

cheers, Ian

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Thanks for the tips Ian.

Can you recommend one from...eBay? Any brands I should look at? Or maybe other places to buy from?

Thanks again

[aarggh]

Happy to help. As mentioned, a lot of people like to bash Chinese stuff, but just checking Ebay now, you can get a 2.2kw spindle and VFD for $320 (link below), which to me is an amazingly good price for such a great and extremely powerful piece of gear. If you've normally been using 1/2" collet routers of the larger variety like Hitachi TR12's or so for general woodwork, a 1.5kW will be more than sufficient for most things, a 2.2kW will blitz them.

The price jump from the common Chinese spindles to the better quality spindles is quite high, but when the spindles are so cheap, I figure why bother, put that money into cutters or better machine parts. If it burns out after a couple of years or so, it's very cheap to replace.

Having said that, the 1.5kw on my main machine has probably done well in excess of 1200-1500 hours over the last several years, and is as smooth and quiet as when I first got it!

The Hitachi VFD's with the Chinese spindles are quite popular as a better quality solution, as it's more likely the VFD will develope an issue before the spindle, and the models such as the wj or sj200's are very reasonably priced, but i'd still buy a Chinese set for economy, but maybe also buy a Hitachi, or a spare VFD, for if there is a failure, or you just want to go up a notch. Vectorless VFD's such as some of these better ones will allow you to machine at slower speeds with no loss of torque, so that fact alone is worth considering, especially for aluminium machining.

Again, I must qualify the failure statement with the fact that I have around 4 or so spare Chinese VFD's bought in case of failure, sitting around gathering dust the last several years! The good thing is they can be bought for as little as $50-$75 inc shipping which makes them a very cheap insurance prospect.

cheers, Ian

220V Water COOLE Motor Spindle ER20 2 2KW Inverter VFD CE Top Quality | eBay

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Great info!

I had a few more questions while I look:
1. If the spindle is water cooled, what kind of water pump do I need? Would a simple aquarium pump work?
2. If the spindle is air cooled, do I need any pump?
3. I would like to use smaller endmills...say around 1/8" or 3mm. Where would I get a collet for those? Ebay I assume, but how do I know the proper size for the spindle?
4. I am in the USA so I will need a 120V version of the VFD. I assume that doesn't matter for the spindle? Many of the VFDs on ebay are 220V, but they say that they may have 120V in stock.

At the moment I am only using my CNC for fun, so downtime is not critical...yet

PS. Love your signature...I am using 3 of these drivers in my current CNC. I thought about switching to Gecko, but didn't want to invest right away.

[aarggh]

I have a large plastic tub at the rear of my machine that holds around 6 litres of undiluted car coolant, and a fairly decent quality but cheap Chinese supplied submersed pump very similar to the attached pic, it's not overly powerful or large. I find I can run the machine for an 8 hour job, and the spindle will usually just be warm to the touch, for smaller jobs of 30mins or so, it barley gets above cool to the feel, so unless your workshop gets quite warm, you don't really need to worry to much about it.

Some people go to the trouble of adding radiators and fans, but I've never found this to be needed myself, and I just really, really, hate the idea of cooling fans in the workshop, anywhere near the cnc machine.

If you go for an air cooled spindle, no pump needed, but you will require really good dust extraction, unless you want to risk the spindle overheating when the fans get clogged with crap. Plus the fans will blow the debris everywhere too. The only people I've seen that were really happy with air cooled spindles, were people who had very good extraction solutions

The collets are easily and cheaply available, in sets or singly, usually ER11 up to 7mm for 0.8kW/1.5kW spindles, or ER16/20 for the larger spindles. I've bought sets to cover all sizes in metric and imperial, but really the only ones I use regularly are, 1/8", 4mm, 6mm, 1/4", and on rare occasions 1/2". The rest I've found to be a waste.

The input level to the VFD is the only connection you need to worry about.

So far as drivers, I couldn't recommend strongly enough to at least plan ahead for a G540, I can absolutely guarantee once you've hooked it up, you will never, ever, regret having bought it. After struggling with crappy controllers for ages, going to the G540 was almost a religious experience for me, the difference could not have been any more extreme. They aren't overly cheap, but I can assure you they are worth every cent. In fact, for all the features it has, they really could sell it for more without any trouble I'm sure.

cheers, Ian

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Thanks again, I am looking into the g540.

Since it has a parallel breakout, shall I assume that you use Mach 3 as well? I will certainly plan on using it for my next iteration.

[aarggh]

Generally Mach3 or Linux CNC are really the main choices for hobbyists using a G540. The beauty of the parallel port is that older computers that have one are a dime a dozen, so a lot of people buy 2 or 3 identical computers and just keep them as spares, so in the event of a hardware failure you can just chuck the hard disk in another and keep on truckin!

cheers, Ian