There are a lot of reasons for not wanting to drill screw and tap your cheap DROs to the lathe. My reasons were that I didn't want to drill and tap holes because moving the lathe away from the wall to get to the back side seemed like way too much work to install $70 worth of DROs that may not even pan out to be good enough. If I was installing a DRO that was pricier, I would do it "the right way". If these inexpensive DROs turn out to be quite impressive over the long haul then I'll endeavor to mount them up more permanently.
:allgood:
Here's some photos of how the IGaging DROs are mounted up to my lathe and the process I'm using. I'm using 3M VHB (very High Bond) Tape. You can get it on amazon or Ebay. I went on the 3M site for surface preparation and temperature recommendations. Ideal temps are 68-degrees Fahrenheit. The surface must be thoroughly cleaned and degreased. I first cleaned it with purple power, you can use some other spray cleaner. Then i followed that with automotive wax and grease remover. The final step is to wipe it with isopropyl alcohol (rubbing alcohol). I'm not sure, but I think you can use denatured alcohol too. I used isopropyl because thats what it said to use in the directions.
The tape is temperature and pressure sensitive. I only keep my shop heated to around 60 degrees, so its a little too cool. So what i did was warm up the area where the bonding is to take place with a heat gun. Don't use a torch or you can cause all kinds of tempering and burning issues. Even with the heat gun, you have to be careful not to overheat any of the areas. Especially don't overheat the painted areas, as you can burn and strip the paint. I am also clamping all the bonding surfaces and periodically heating up the areas around them to activate the adhesive and to give the adhesive a good chance to ooze into all the micro-pores. I didn't sand the the surfaces but, i read that it can be beneficial to do so. I also read somewhere that if the surface is powder coated that there is a special tape for that surface. Apparently this stuff doesn't like to stick to powder coat.
So far this thing has been clamped up for about 10 hrs overnight. I'm gonna give it a full 24 hrs because of the shop temperature, heating the areas periodically with the heat gun, just to be sure it's not gonna come apart.
I was able to use the existing brackets that came with the DROs by doing a little creative reworking of the brackets.
Every lathe is a little different, some of the older lathes don't have too many flat and square surfaces to mount things to, so if you have one of those, this tape method may not work at all. On my SB9 I 'd be able to mount on the back side, no problem. But the cross slide is a different story, I'd have to lay the scale flat next to the cross slide. No matter what lathe you're mounting to, you're going to have to get a little creative making or reworking the brackets.
Anther method that might work is to use an epoxy putty such as PC7 to mount them up.
This is a picture of the lathe with the clamps on it clamping down all the mounting points.
The cross slide clamped up.
The back side clamped up.
A closeup of the back side mounted to the carriage.
Marcel