Becoming hobby machinist in the near future.

I started on the DRO installation. Came across the first issue which is that the cross slide scale will cover the cross slide locking screw :(
The instruction included were not very good, and the video from DRO Pros (which is very useful) avoided that topic. I did not want to loose the locking functionality so I emailed QMT/PM to see what the options were. They sent me a PDF that showed more details on the installation with a couple of "options". The solution that looked least invasive was to build a shim to hold the scales and reader head far enough away from the slide body that I could get a wrench in to the slot and lock using a hex bolt.

First order of operation was to produce a bolt that fit. I had on the right size but the wrong length. I cut it down to size and removed the thread "shoulder" near the head so it would be able to screw in closer to the body. Then I shaved a few thou off the head to make it have a lower profile.

After that I checked my wrenches and determined that 8mm of space would be enough, so to error on the safer side I decided to go with a 10mm thick shim. I would need to add the same height to the scales and the reader head, so I decided to start with a single bar of mild steel and square it, then face it down to 10mm thick and the correct width (28mm) to fit the scale (vertically) and the reader (horizontally). Once the piece was sized I cut 3 pieces (two for the scales at 23mm and one for the reader at 62mm) with my fancy power band saw (okay it is an inexpensive dewalt hand held unit but it does the job). From there I faced the ends and brought them to final size (21mm and 60mm). Then I milled a slot on the scale risers. Later today I will mill the slots for the reader riser.

I will most likely need to find some longer screws. Alternatively I could have mounted the risers and tapped them for the current screws, but I was thinking that I wanted the screw to touch the lathe rather than just screwing in to the riser. This way the riser is just a shim and not integral to the setup beyond adding distance.
 
Did they show the aluminum locking head from the other side like Mark, and David have done?
I found it....
www.hobby-machinist.com

Pm1340gt Cross Slide Lock Mod For Dro Machines

One of the issues when adding a DRO scale to the cross slide is that it often blocks the ability to use the lock. On the PM1340GT, they use a 6mm Allen screw on the right side of the cross slide which is completely inaccessible with the mounted DRO scale. I considered various options, but I...
www.hobby-machinist.com www.hobby-machinist.com
 
Aukai said:
Did they show the aluminum locking head from the other side like Mark, and David have done?
I found it....
www.hobby-machinist.com

Pm1340gt Cross Slide Lock Mod For Dro Machines

One of the issues when adding a DRO scale to the cross slide is that it often blocks the ability to use the lock. On the PM1340GT, they use a 6mm Allen screw on the right side of the cross slide which is completely inaccessible with the mounted DRO scale. I considered various options, but I...
www.hobby-machinist.com www.hobby-machinist.com
Click to expand...
This was not one of the options shown. I think because it makes using the steady rest harder. I think the most I am adding has less overall impact than the mod in the above post. I will post pictures when I get finished, but since the distance is pretty short I think the risers will be ok. I also like the fact that the solution I am using does not put my hand closer to the chuck :)

Although now that I look at that solution I guess it does not really require any modification to the lathe (no hole drilling to put it on). That is slick. I am guessing the the lock is not are secure as a screw into the ways, but also will not put dings in the ways like I imaging too much force on the screw will do... Lots to think about. The beauty of the riser is that later if I want I can just remove them and move to using something else.
 
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I mounted my cross slide scale on the tailstock side, and positioned the scale for an access port to the cross slide locking bolt. The bracket is a piece of 1/4" thick aluminum angle with a window cut into it. Full details are here.

IMG_5655.jpeg


Stainless sliding cover.

IMG_5745.jpeg
 
Rodneyk said:
This was not one of the options shown. I think because it makes using the steady rest harder. I think the most I am adding has less overall impact than the mod in the above post. I will post pictures when I get finished, but since the distance is pretty short I think the risers will be ok. I also like the fact that the solution I am using does not put my hand closer to the chuck :)

Although now that I look at that solution I guess it does not really require any modification to the lathe (no hole drilling to put it on). That is slick. I am guessing the the lock is not are secure as a screw into the ways, but also will not put dings in the ways like I imaging too much force on the screw will do... Lots to think about. The beauty of the riser is that later if I want I can just remove them and move to using something else.
Click to expand...
I followed what Mark did on my lathe. Besides locking the slide in place I’ll actually use it to put more drag on the slide so I can fine adjust a little easier. It locks the slide extremely well. I can’t imagine the set screw would do any better.
 
Yesterday I was able to put the DRO on the Cross Slide. I still need to put the cover on, and route the cable (and adjust the entire set up down since as it sits there is not enough room for the cover plate). It works!

It is taking longer than expected because I had planned on getting the Lathe in the winter but missed the boat so it was delayed to spring. I am a beekeeper (hobby) and in the spring that takes a lot more time...


Dro001.jpg
 
Whew... I finally finished installing the DRO on the lathe. It would have been nice to have a second set of hands at least to remove and install the splash guard, but I was able to manage myself with only a limited number of curse words and one minor cut on my finger (which happened opening a plastic bag with my newly sharpened pocket knife :).

So my take a ways:

1) It was not as hard as I thought it would be.
2) Watching the DRO Pros videos really helped, the documentation provided really sucks even though it looks like they tried to make it good. I think the issue is that the guys who wrote it need to watch someone who has never installed one do it with their doc, and fill in the blanks when the person says WTF now.
3) Drilling and tapping is scary to do on a brand new piece of equipment.
4) I broke one pilot drill in the process, cheap drill.
5) I broke one .25" endmill when I was shortening the debris guard for the long scale. It was going so well but I accidentally bump the feed rate when I heard a vibration. My mill it really too small to mill that part so I was amazed how well it did. Also note the endmill was one I got on eBay as used endmills by the pound. And I have been using them to cut mild steel. The price was perfect for me to get a bunch of play endmills that I would not be upset if I broke.
6) There is not a great place to mount the head with the given bracket on the 1340GT, I put it on the side of the electronic cabinet. DRO Pros example lathe has a place to mount on the front of that box. It is still very visible in within reach. Later I might try an move it.
7) The back of the ways bulge slightly so in mounting the long scales I used the grub screws aggressively to get the scale clear of the bulge. I took me longer to get the scale flat than just about any other operation.
8) On the back of the cross slide I found a set of predrilled holes that almost perfectly matched the bracket for the long side reader. I decided to use those rather than drilling new holes, but it meant I needed to mill the slots a tiny wider to get a good fit. Those holes might be used for some other attachment, but for now it is going to be my DRO reader.

I probabaly should have taken some pics but I forgot.

Next step, cleaning up the mess I made, then re checking the level
 
Oh and I ordered a cheap Tach on ebay as was noted in some other posts. I guess I still have a bot of drilling and tapping to do...
 
I know this will not be too exciting to most of you, but it is very exciting to me. Today I successfully cut a 20tpi thread on a rod. This does not fit anything, is not to spec, is pretty useless since it is not a standard size, but it is my first time single point cutting a thread,

Threads001.jpg


I used a few steps:

1) faced the end of the rod
2) turned down the rod by the smallest amount possible and
3) cut a way a small landing zone for the thread to stop (did not cut deep enough but at least I did not break the insert)
4) Chamfered the end to give is a softer lead in
5) Slowly cut the thread using 2 techniques (both I set the cross slide to a Zero height to start and used the compound for depth of cut)
a) I used the half nut (Engaging and releasing) for part of the thread to make sure I understood getting back on the thread after moving the carriage.
b) I used the half nut permanently engaged for the second part.

In both cased I set the proximity stop to stop when the tool reached the landing zone.

The one major discovery is that the compound scale is 90 degrees out of phase so to get a 29.5degree cut I needed to set it to 60.5 degrees.
 
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