Precision Matthews X Axis Power Feed

[mksj]

The mounting instructions are generic. The location of the limit switch depends on the axis and the machine. On the X axis it is typically mounted to the saddle as shown in the directions. Almost all drives are NOT machine specific and almost always requires fabricating brackets, standoffs, etc. to make them work. One of the biggest mistakes I see people do with DRO and drive limit switch installs is to try to use the stock brackets and kludge something together. Most of the time you need to mock up everything, make sure you have the appropriate clearances and then mount everything.

The wire at the bottom of the switch can be held in place with cable restraints to prevent it from interfering with other machine components. I would have no issues with using the saddle threaded holes or tapping new ones being very careful to not thread into something other than the saddle. In this case use the current holes in the saddle make a bracket and countersink the heads, then mount the switch to the bracket.

Quality of components is proportional to the price for the most part, but there are enough of these installed that I would be confident that although the switch my not look high end, that it will work. If I had a limitation as to the switch size or I wanted higher quality there are plunger type limit switches that could be used. I have installed these on custom axis drives that I have made.

 

[erikmannie]

Speaking of spacers, PM provides a pair of spacers that one can use instead of the single spacer pictured above. One of these alternate spacers is shown below.

 

[erikmannie]

I will probably use the single spacer:

 

[erikmannie]

Here is a photo of the height of the limit switch and the front of the saddle:

 

[erikmannie]

Here is the max height that I have to work with.

 

[erikmannie]

Here are the stops provided in the PM power feed kit. They mount in the dovetail slot at the front of the table:

 

[erikmannie]

It looks like I will have to remove the limit switch when I access the ball oiler. How often do you guys put oil in these?

I also note that the forum software sometimes rotates my pictures.

 

[erikmannie]

So what I was calling the spacer will now be referred to as the standoff.

My dad came by and said that drilling and tapping the saddle would be more work than using the existing threaded holes. I wonder what the saddle is made of; it appears to be a casting.

So I am moving forward with a plan to drill two holes in the standoff that came in the kit. The threaded holes in the saddle are M5 X 0.8. A 20mm shank is a little too long and a 15mm shank may be a little too short. I found some in 16 and 18mm. I will counterbore the standoff so that the limit switch can be flush up against it.

I will cut a clearance out of the standoff so that I can access the ball oiler. This would require me to remove only the limit switch when I want to oil here.

 

[erikmannie]

Even though I used plenty of grease, the grease doesn't seem to stay on the drive gear. I operated the power feed back and forth about 10 times.

 

[erikmannie]

I received the replacement bracket from PM. I will go easy on this one.