MagXact scale install....chasing my tail on tolerances.

[coolidge]

Did you get more than a one page manual that was folded into four squares? I made the assumption that using the kit from PM would be easier than from someone else. After getting this one, I'm 90% sure the DR PRO kit would have been easier to install.

I received the 9 page PM installation guide bound between plastic covers with the shipment from PM. There's also an 8 page quick start user manual on PM's site and the full book user manual is available from Electronica the company that manufactures these DRO's.

The kit is exactly the same from either place in terms of hardware and installation so your frustration would be the same, only the frustration would cost you another $1,000. The other company only offers the EL700 (aka MagXact) in a 3 axis lathe kit for (cough) $2,000. That's almost $1,000 more just for an additional 8 inch 3rd axis.

The frustration factor is due to the irregular casting surfaces the scales need to be installed on. I have installed 4 or 5 of these prior, it varies machine to machine. The provided brackets work for some axis on some machines, others required some custom parts, different screws, fitting or just re-thinking it like going with an aluminum flat bar on lathe Z axis.

BE ADVISED - I installed a EL400 on a mill earlier this year. The X axis was losing it's damn mind! It would work then stop registering movement and lose position by large amounts. If you were moving the table left to right it would follow along for a while, then start counting backwards the other direction even though you were still moving in the same direction.

Troubleshooting took place with the vendor, their best guess was a faulty power supply board and they sent one. A few hours after that call I figured out the issue and fixed it. The serial ports, cables or both on that EL400 are garbage. I remembered plugging in the cables and they were so sloppy loose fitting I didn't think they were making contact with the pins. I had tightened them down with the thumb screws. Sure enough I took a screw driver and wiggled the X axis cable up and down while tightening it some more and presto problem solved.

I have not checked the MagXact yet but since the same company makes this stuff I'm half expecting the fit to be no better. So make sure the cables are snugged up good with a screw driver.

 

[coolidge]

but I'm getting a weird bow between the blocks that I just can't get out.

The scale end caps are probably not screwed onto the scale flat with the scale, but tilted up or down so when you screw them down it bends the scale bowing in or out. I recall having to loosen the end cap screws, press both the end cap and scale down flat on a flat surface while tightening the end cap back on.

 

[mksj]

On longer scales there are intermediate L shaped blocks that secure the scale and prevent it from twisting or bowing. You can make them out of aluminum. If I have an issue with flatness, I often will use 1/2" aluminum flat-stock mounted at 2 or 3 points to the machine and then attach the scale to that. In some cases I will use small set screws in the corners for adjustment as well as slotting for up down alignment. I have the same scales on my mill, they are not that fussy.