Customer Reviews

Grizzly G8689 Mini Milling Machine

5 star:		(3)
4 star:		(3)
3 star:		(0)
2 star:		(1)
1 star:		(0)

 

 

As noted by a previous reviewer, this same model (all made by Sieg in China) are available from a variety of sources. I purchased mine from Grizzly, largely because of the support that Grizzly provides. If I were to purchase this same milling machine again, I would probably go with Micro-Mark which is about the same price. The big difference is that the Grizzly version uses 0.060"/turn on the x and y axis and 0.0625"/turn on the Z-axis, while the Micro-Mark uses 0.050"/turn on all axis. It's a lot easier to dial in, say a 0.384 movement at 0.050"/turn than it is to divide 0.0625 into 0.384 to determine the number of full turns and the add'l thousands needed to hit 0.384 exactly.

Anyone considering a small milling machine probably knows that you'll spend nearly as much on tooling as the initial purchase price of the mill. With this mill, plan on additional purchases of a belt drive kit ($120)to replace the noisey, failure prone gear train and an air spring kit ($40)to replace the cheesey torsion spring mechanism. Without the air spring kit, the mill head will occasionally drop 50 thou or so, resulting in an undesired gouge in your work piece. Both kits are available from LittleMachineShop.com (an Amazon supplier).

Provided that you don't push it too hard, this little guy will handle machining of small steel, brass, aluminum, delrin, etc. work pieces with accuracy of +/- a few thou. To do that, however, plan on investing a considerable amount of time on tuning the machine by polishing and adjusting the gibbs and tweaking the nuts on the lead screws to minimize backlash. Besides improving the performance of the machine, this tuning will improve your understanding of how all the pieces fit together to perform the milling function.

I bought mine from Harbor Freight, an attractive option if there is a store nearby. None of these mills are ready to run out of the box, a considerable amount of cleaning and fine tuning is needed first. However, someone who is interested enough in the intricacies of machining will not find these tasks much of a problem. The Harbor Freight mill has the annoying 0.060"/turn axis, but I solved that with a Sumatech digital readout kit. Another good economical choice in DRO's is Yadro. To save even more, just mount cheap digital calipers to the axis and read them directly. The bottom line is that you will spend at least as much as you did on the mill outfitting it with bits, vises, clamps, and useful improvements like the gas spring and belt drive modifications. However, once you've spent about $1,000, you will have a capable and accurate little machine shop on your workbench. For a small machine, it is surprisingly powerful. I've cut difficult to machine materials like stainless steel on it, breaking a few bits in the process but so far no parts of the machine itself.

A few companies sell basically this same machine in the United States. I myself bought one from Harbor Freight, and it is an OK machine within its limits. The thing about the Grizzly version is it has an MT3 spindle taper, which is basically a drill press taper, instead of the R-8 taper that most other companies in the United States offer. R-8 is not a world standard by any means, but here in the US it is by far the standard spindle taper for "small" (as in Bridgeport size on down) vertical milling machines. Why Grizzly continues to offer their machine with the odd taper is beyond me. If you buy the Grizzly version, spindle tooling will be somewhat harder to find, probably more expensive, and if you upgrade to virtually any larger mill later on you will have to buy it all over again. Also the MT3 taper, in drill presses, normally does not use a drawbar whereas R-8 always uses a drawbar. For this reason MT3 has a more gradual taper so the tool wedges and does not drop out. What this means in milling machine use is that the MT3 taper tools wedge tighter in the spindle and are harder to eject when you want to eject them than R-8 taper tools.

I can understand Grizzly maybe offers better customer service on many machines. But all the parts of this particular machine are readily and cheaply available from LittleMachineShop.com anyway, so unless it is initially defective I see no big advantage. And HF has come through for me on customer service for defective items in the past, though they sure don't seem to emphasize service much on their site or in their catalogs. LMS is actually recommended by the Chinese manufacturer of these machines as a world-wide service parts supplier, by the way.

There are about 3 or 4 other companies that sell a version of this mill. Grizzly has the best motor and table that I have seen. Micro-Mark has a different scale on the feeds, but if you go with a digital readout, it doesn't make a difference. Plain and simple, this is the one to go with.

I have the Grizzly G0516 Combo Lathe/Mill
Same milling head and column as the G8689 Mini Mill.
MT3 spindle nose versus R8 is a good comment.
I have used both styles over many years.
Each machinist has their own preference. R8 can deliver a lot of torque to a tool bit whereas Morse Taper can slip. However, the Minimill has very limited power and having R8 on the spindle nose is like having a Caterpillar Bulldozer blade on a John Deere farm tractor. Just my 2 cents worth.
There are some other things that apply to all iterations of the Minimill.
Nylon drive gear, poor fitment of the gear train giving undue backlash and noisy running. It is what it is, a simple milling machine. Poor quality control at the factory can generate frustration. I wanted to fit a Dial Indicator on the column and planned to use the lower stop for the purpose. Couldn't remove the stop w/o lifting the whole milling head off the column and triming the dovetail fit on the clamp.
Then I found the clamp interfeared with the scale on the column, had to mill a relief on the clamp. The scale doesn't match the head location very well on the combo machine. The head feed rack is too short for all milling applications. I fitted an extra rack in the slot. Now have full head travel. I agree with the observation about the counter ballance spring. It's not worth much.The spring is deficient when using the machine as a drill press. I use the microfeed for all milling operations.
Grizzly service is just super. Nothing like it from any other Machine Tool Company in the US and that is the truth! I ran the service & engineering support operations for a machine tool company and we could never match what Grizzly provides in terms of support and spare parts.

Great service Grizzly!

The Grizzly version uses 0.060"/turn on the x and y axis and 0.0625"/turn on the Z-axis, while the Micro-Mark uses 0.050"/turn on all axis.
For the metric oriented hobyist, the Grizzly is easy to convert to metric measurements.
0.060"/turn is 1.524 mm/turn (only 0.024mm or 0.0009" inaccuracy).
In addition, use a 30 division dial and each division is 1.524/30=0.05mm (0.0508mm or 0.0008mm accuracy).

Fast shipping, came well crated, works great after clean up and setup. If you are serious in tolerances than disassemble, lube and reset machine and it is a winner.

Use it as a hobby machine and small one off items.