Setting up Fadal rigid tap

Setting up rigid tapping isn’t hard per se, but finding the right set of instructions was more difficult than I expected. ITSCNC and FadalCNC both have a ton of Fadal manuals and technical instructions, if you’re ever looking for info on your machine. For rigid tapping, ITSCNC has two helpful manuals: rigid tapping installation guide, and spindle drive installation guide.

The rigid tapping guide is not necessarily that useful if you already get the Fadal control scheme, as there really aren’t that many cables involved in setting up the whole system. But the settings changes in the spindle drive installation guide are really, really helpful (some more obvious than others). The big one is that your spindle will not run at all unless you change the control signal the inverter expects from 0-10V to +0-10V. The rigid tapping EEPROMs open both the forward and reverse relays, and use the full range signal to get faster spindle reversal (I assume, anyway). There are a bunch of other drive parameter changes described in the installation guide to get it working 100%.

Getting coolant set up

When I picked up the Fadal, one of the big upgrades I was looking forward to was easy to use coolant. I had bad experiences with coolant on my PM940: coolant growing stuff, limited pumping power and coolant volume for flood coolant, and poor efficacy from MQL/mist coolant. The Fadal enclosure and coolant tank solved most of those problems.

Picking a coolant is a game that even most of the seasoned vets on Practical Machinist don’t seem to have a good recipe for. I went with Trim Microsol 690XT because quite a few members of PM reported getting long life and no issues with smell or rust.

I mixed in a 5-gallon bucket, and checked concentration with a refractometer, to confirm it was in the 10% range, the poured the bucket in the coolant tank (which was already cleaned — I also replaced the coolant hose). For some people concentration alone isn’t the best indicator, at least according to some of the applications engineers for these products. Hard water or pH imbalances causes issues, the details of which are over my head.

Now the real issue starts once you have the coolant mixed and in the machine. That problem is the way oil which is mixing into the coolant, and which allows the growth of anaerobic bacteria that make the coolant smell (and presumably reduce the lubrication qualities of the coolant). I bought a NexJen 1500 oil skimmer, which uses a pump and float in the tank, as well as a small separate tank to actually skim. I hooked this up to standard 120V household timer, and it runs for about 1.5 hours every day, based on the results I initially achieved running it for several hours.

The Fadal makes some money

The first batch of parts off the Fadal — a rerun of some parts I made on the PM940 last year. So much easier to run (because of the ATC and better repeatability), and definitely valuable for helping my figure out my workflow and starting to optimize programming and running the machine.

The softjaws hold two parts in each of three operations. First, cutting one end to length; then cutting the other end to length and surfacing the curved surface; finally, drilling holes and putting in countersinks. All edges are deburred in the machine, which I haven’t done before (because without an ATC it meant manually changing another tool in, when I was already standing there and could do it by hand while the 3D surfacing was running). The only real learning experience there was implementing a trace toolpath to go around the top of the curved surface, which worked out nicely.

The other learning experience here (possibly re-learning, since it’s been so long since I did this on the PM940) is that it’s easier to leave a lot of extra material while saw cuttingĀ  to make up for angled cuts and poor surface finish. I left an extra 1/8″, turning a 1.25″ part into a 1.5″ part, but that took my defect rate from ~50% down to 0%. All of which goes to say, it’s probably better to just have a good saw.