# SB1007 "Heavy Ten" Impressions and Experiences



## jaek (Nov 25, 2022)

This lathe deserves its own thread, even though Grizzly may be discontinuing it.

Note: Take everything I say with a grain of salt. I am a self-taught hobby machinist, with most of my experience is on a MicroMark 7x16 mini-lathe. My goals in upgrading were a larger work envelope, more low-speed performance especially for threading, and general improved performance. Living on a hill a city means I have limited space and weight capacity for tools.

The SB1007 is almost an exact copy of the Emco Super 11. You can read all about the original on www.lathes.co.uk - it was a high quality machine.

Unboxing was pretty straightforward. The lathe came with minimal accessories - a 3-jaw chuck w/ reversible jaws, an outboard spindle spider, an MT5 to MT3 adapter for the spindle, a 4-way toolpost, and a variety of tools. The spindle is D1-4 w/ MT5 taper, the tailstock is MT3, the lead screw is 8 TPI. Cross slide and compound slide lead screws are metric - 2mm and 1.25 mm respectively. Initial spindle break-in and test cuts went fine.

Stay tuned for more.


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## jaek (Nov 25, 2022)

*Motor*

The original Maximat had a two-speed motor and a four-speed geared headstock. The SB1007 has the same user interface, but behind the scenes is a Delta VFD022E21A with two preset speeds and a three-phase motor. The VFD is configured with a five-second ramp-up/ramp-down time, and the "Jog" function actually puts the lathe into forward mode.

True variable speed only requires replacing the 1-2 switch with a potentiometer and adding a tach, plus some control panel rewiring and VFD reprogramming. The 10k pot was $41 from automationdirect.com, a tachometer and modbus adapter were another $40 from Amazon.

After more time and false starts than I'd like to admit everything ended up working. My next steps are to add a 12V power supply inside the cabinet to power the tach and a braking resistor for faster stops. After that I might try to hook up a limit switch or proximity stop for threading to a shoulder.

It's a little surprising that Grizzly didn't configure the lathe with variable speed to start with, but they must have had a reason.

Pictures to follow.


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## markba633csi (Nov 25, 2022)

41$ for a pot? That seems high
It is odd that they omitted variable speed
Does the onboard VFD not have enough aux power to run the tach?


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## jaek (Nov 25, 2022)

It’s an industrial pot with mounting and actuator and everything, not just bare leads. I could have spent more for sure.

Not sure if the VFD has a spare 12V output. Will have to check the manual.

The design is a little weird - probably contributes to the high price and what must be low sales.


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## markba633csi (Nov 25, 2022)

I checked- it has a 24v output but only good for 20 mA. Probably will need an external tach supply


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## DavidR8 (Nov 25, 2022)

You can also get 120v tachs.


			https://www.amazon.com/Tachometer-110V-230V-Measurement-Accuracy-Digital/dp/B08CHKHNBN


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## jaek (Dec 12, 2022)

One quirk of this lathe - the height from the top of the compound to the spindle axis is only 23 mm aka 0.905". This is a little small for an AXA toolpost. 1/2” tool in a standard tool holders won’t fit. 1/2” in an oversize holder or 3/8” in a standard holder do work.  The normal Dorian holders will hold a 1/2” tool. Boring bar holders are generally fine; cutoff holders are generally not.

Just something to be aware of.


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## Dabbler (Dec 12, 2022)

jaek said:


> the height from the top of the compound to the spindle axis is only 23 mm aka 0.905"


That is very small...  wow.  then it is a 0XA for you if you go QCTP.  You might be better of with a 4-way, winch is more robust in the smaller sizes.


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