When you are installing DRO scales, they must be placed so that they are working within the same plane as what they are measuring. The instructions provided with the scales state they must be parallel and perpendicular to the machine slide movement within 0.1mm (.004"). Unfortunately, most of the cast surfaces of the mill are not square to the machined surfaces, mostly due to pattern draft. We will have to install square surfaces onto the mill for scale attachment points.
A DRO is probably one of the most important upgrades you can make to a manual mill. By removing concerns with screw backlash or losing count of hand wheel rotations, the DRO allows you to work faster with less chance of user error. Even compared to a new mill, the linear scales of a DRO system are much more accurate than typical mill lead screws. Add in a few advanced features such as center function, bolt circle function and the ability to easily switch from metric to imperial units and it's easy to see why a DRO system is such a popular upgrade.
The Grizzly G0678 mill has been a good mill, but from the very first day of ownership the oil lines have always had a slow leak. After the mill sat for a week or so, one side of the oil system would always drain down into the drip pan so it would take several pumps from the oiler to get the system full and flowing again. The DRO installation was coming, so it was time to get this annoyance fixed.
While the handwheels on the Grizzly G0678 mill are large and of a decent quality metal construction, I wasn't very happy with the stock axis lock handles or dial lock thumbscrews. For the DRO installation, the lock handles for the X axis would have to be changed anyway so it was a good time to upgrade the knob hardware to something that's a bit nicer to use for all the lathe axes.
For several years I've been using a LED work light bought at the local home improvement center for machinery lighting. The promise of LED lighting is a bright, low wattage illumination source that will last a long time. While this light did great on the first two items, it didn't nearly have the promised lifespan. I could just replace the light with a new one, but then I would have to adapt the custom mounting bracket for a different light, so it's easier (and cheaper) to repair the old one.
Several years ago I chanced upon a really good deal on an almost complete Greenfield Tap & Die 2" diameter threading die set. On the lathe, most of the time I just single-point threads of the size covered in this set, but sometimes it would be handy to use a die, especially for tapered threads like NPT. Because of it's long handles, using the set's die holder is impossible on the lathe so I will need to make a holder to support the dies with the tail stock.
Construction continues on Mr Pete's DA Wobbler steam engine so make sure to check out Part 1 of the build first. With machining on most of the parts completed, it was time for the initial fit of the cylinder to the plinth to determine the location of the steam ports. In his video, Mr Pete showed a clever trick to get these ports perfect the first time. A small sharpened rod is inserted into the ports in the cylinder and used as a transfer punch to mark the position of the steam holes in the plinth.
In the early spring, Mr Pete of Youtube fame posted a series of videos about constructing a Dual Action (DA) wobbler model steam engine from bar stock. While I already had an unbuilt casting kit from PM Research of a similar design (the 2A kit), I thought it would be a good idea to build this engine first as a learning experience. When you screw a part up, it's easier and quicker to make another from bar stock than order a replacement casting from the manufacturer.
Several years ago I made a LED spindle light for the mill. While it worked well enough at first, over time I became dissatisfied with the amount of light it produced and the lack of an oil-proof enclosure was making it unreliable. It was time to build a new one and improve upon the original design by sealing the LEDs in epoxy and ramping up the light output with 3 COB halo rings.
While this Kreg featherboard fit reasonably well to my new Dewalt table saw, I wasn't that enamored with the plastic wedge-lock friction-fit hardware. It's a universal design created to fit as many sized miter slots as possible and while it works reasonably well a direct fit into the miter gauge T-Slot would work better. Luckily it looked pretty simple to convert the hardware to use custom milled aluminum T-Slot holders.