Thread: MD45/HM46/RF45 DRO Install as requested..

Hi Variant 22, brilliant work you have done with the DRO. I'm wondering the particular mill you have is it a General Tools mill or a Hare and Forbes mill.

Originally Posted by Alby123

Hi Variant 22, brilliant work you have done with the DRO. I'm wondering the particular mill you have is it a General Tools mill or a Hare and Forbes mill.

Thanks for the thumbs up Alby123. I am not going to mention the company, but if you search Google you can find it. It is the SM-MD45. The reason I am not mentioning the company is their service was terrible. It started out great, until they missed the delivery time frame they set (a month later than the "worst case"), then the mill turned up with damage, and missing a number of features listed on both their website and my invoice. To cut a long story short, they ended up giving me a $200 discount to make up for features which would cost me high hundreds to buy. They also made no effort to rectify the damage on the machine. I would never deal with or recommend that company to anyone.

HI,
Thanks for the Reply in regards to the Scale lengths and for the Tips. The Mill Drill that I have is a Top Tech DM-45. According to the My Manual the Table size and Travels are actually the same as Your SM-MD45. Table 800 mm x 240 mm, X:560 mm, Y:230 mm, Z:460 mm. I need to recheck the X (560mm), I seem to remember it being a bit less than what the Manual stated. So I am probably going to have to get at least one different length Scale.

I'll Edit that last bit. I am going to be fitting the Dro Scales to the Table Long & Cross Travel and to the Mill Head Travel. I have a Digital Scale (mini dro) that I bought of Shars for the Quill. Since My Z axis is longer than the 420mm Scale, I will have to either put up with a reduction in travel or buy another Scale to suit.

Just out of interest, what were the majority of bolts you used?

Great thread,it's helped me with mine. My y-axis is now looking similar to yours. I've been using M5 bolts for bolting the aluminium fixtures to the mill, and will probably be using m4 for bolting the rails to the aluminium - because it's what came with the kit and I have a few lying around.

Originally Posted by j3dprints

Just out of interest, what were the majority of bolts you used?

Great thread,it's helped me with mine. My y-axis is now looking similar to yours. I've been using M5 bolts for bolting the aluminium fixtures to the mill, and will probably be using m4 for bolting the rails to the aluminium - because it's what came with the kit and I have a few lying around.

I can't remember exactly. Either M4 or M5 SHCS I suspect. I think more leaning towards the M4 side. Basically whatever fitted between the scale slots, mount slots and whatever I had on hand. Sorry I can't be more specific than that - I removed the DRO from the RF and put it on another machine. That being said the RF is undergoing a CNC transformation (not recommended) - so DRO would have been made obsolete.

Originally Posted by variant22

I can't remember exactly. Either M4 or M5 SHCS I suspect. I think more leaning towards the M4 side. Basically whatever fitted between the scale slots, mount slots and whatever I had on hand. Sorry I can't be more specific than that - I removed the DRO from the RF and put it on another machine. That being said the RF is undergoing a CNC transformation (not recommended) - so DRO would have been made obsolete.

Haha, thanks, I am going to remove it from the RF within a year and CNC it too. Looking at stepper motors from the corner of my eye now - China's steppers with feedback seem promising (closed loop).

Couple more questions... Do you happen to know the angle of the dovetails on the front of the x-axis? I measured some photographs at 70 to 75 degrees (or 20 to 15).

Also, does your tramming fixture prevent the head from falling 'forward' as you loosen the main 3 tightening bolts? Although advantageous, I would be worried about the bolt's strength to do so. I am also hesitant to drill into this area to add any sort of stress concentration.

Originally Posted by j3dprints

Couple more questions... Do you happen to know the angle of the dovetails on the front of the x-axis? I measured some photographs at 70 to 75 degrees (or 20 to 15).

No idea on the dovetails. You can cut a paper template and fit and snip. Then measure. I could have a look on the weekend if you wish.

Originally Posted by j3dprints

Also, does your tramming fixture prevent the head from falling 'forward' as you loosen the main 3 tightening bolts? Although advantageous, I would be worried about the bolt's strength to do so. I am also hesitant to drill into this area to add any sort of stress concentration.

The tramming fixture was merely to put a bit of pressure on the points needed whilst tightening the bolts. Essentially stopping it pulling off center. It's since been removed. I would probably make it in steel if I were to use it again. It was only bolted to the machine at one end. The other end the screws preload the head tilt. It does absolutely nothing to stop the nod - which quite frankly is significant with these machines.

Originally Posted by j3dprints

Haha, thanks, I am going to remove it from the RF within a year and CNC it too. Looking at stepper motors from the corner of my eye now - China's steppers with feedback seem promising (closed loop).

I'm running Nema 34 servos with additional encoders on the rear shaft. Keeling branded. 850oz on the X and Y and 1150 on the Z.

That being said, I would think carefully before you commit on the CNC conversion. If I were to do this again I would go with a much more capable machine to begin with. Remember that more capable machines really only consume the same footprint in your shed as the 45. My Deckel FP2 for instance takes about the same amount of space as the RF.

Use the RF to learn, have fun, enjoy the shed. Mine got me started and gave me a lot of joy. Then move on to something else when you know what your doing, before getting in too deep and dumping money into it.

Anyone that owns a boat or a pool knows what I'm talking about...

Originally Posted by variant22

No idea on the dovetails. You can cut a paper template and fit and snip. Then measure. I could have a look on the weekend if you wish.

The tramming fixture was merely to put a bit of pressure on the points needed whilst tightening the bolts. Essentially stopping it pulling off center. It's since been removed. I would probably make it in steel if I were to use it again. It was only bolted to the machine at one end. The other end the screws preload the head tilt. It does absolutely nothing to stop the nod - which quite frankly is significant with these machines.

I managed to make a few dovetails, just using the bandsaw and a file. Not very accurate but they don't need to be - accuracy will come from shimming, slides etc.

Question - The reader head seems to have some 'spring' in it, and likes to sit at an angle. Did you force it parallel with the slide when you bolted it in? If it's not free to move where it likes it causes some (very small) deflection.

This is a big job, I just finished the x-axis and y-axis scale mountings. Boy my shoulder has had a workout.

Did you force it parallel with the slide when you bolted it in?

You should set the read head parallel to the scale. There is a specification for how parallel this should be. Most of the DRO's don't come with very good instructions (read useless). As for most things Grizzly in the US has good manuals that they have written, if you can work out which model you have. With a DRO it is pretty simple. Just look for a Grizzly DRO instruction manual.

The read head has springs in it to cause this tendency to sit at an angle. Straight is how it is designed to sit.

Dean

Originally Posted by Oldneweng

You should set the read head parallel to the scale. There is a specification for how parallel this should be. Most of the DRO's don't come with very good instructions (read useless). As for most things Grizzly in the US has good manuals that they have written, if you can work out which model you have. With a DRO it is pretty simple. Just look for a Grizzly DRO instruction manual.

The read head has springs in it to cause this tendency to sit at an angle. Straight is how it is designed to sit.

Dean

Thank you, mine came with none. I have done this now (Easson manual) and the DRO is working. Wow, quite a few days work and probably more than a metalworking novice like myself should bite off. I intially thought "OK DRO purchased I'll just wack it in in a couple of hours when it gets here" lol...

Still, it was pretty awesome to see a full turn of the handwheel come up as 2.5mm (correct). then 5, 7.5, 10, etc. for each full revolution. And back to 0, so it holds its place. Hopefully it all holds up under load. For now though I need a rest...

Thanks to variant for a great thread. I did mine slightly differently, and I got a 150mm z scale for the quill (I rarely move the z).

"OK DRO purchased I'll just wack it in in a couple of hours when it gets here" lol...

I know what you mean. I spent many hours working on my X axis scale mount and then realised that my idea was taking up too much room so I pulled it all out and I am still trying to decide what to do.

I have fitted the Z scale and it works well, but I rarely make use of it as I have got used to using the compound for precise movements and I am not going to put a scale on it.

Dean