Thread: Mill DRO

I would recommend using 5mm angle for strength when something gets dropped and because it has enough thickness to tap into to save drilling a heap of holes into the table.
When you start adding them up there is 2 for the scale and 3 or 4 for the scale cover, where as you can get away with 2 or 3 holes in the table to mount the angle and all the other holes go into the angle only.
Not sure what your table is set up like but I was able to remove the original table end stops and incorporate them into the angle holding brackets to save holes in the end of the table.
You may get away with the power feed stops in their original T slot depending on the scale size and your table height.





You can see the 2 counter sunk socket screws holding the center of the angle in this photo, they were the only holes drilled.


The T nuts on the end don't need to be any longer than about 25mm to hold the angle and I think you will be fine with vibration because the angle is flat against the table. I painted both the angle and the table before mounting to stop rust and before final fitting I put a bead of no more gaps along the top to stop anything getting down their as well.



Dave

Dave is your scale going to be mounted vertically or horizontally?

I mounted it vertical, it has been mounted for a while now.
You can read more about it here
http://www.woodworkforums.com/f65/in...0-52-a-115786/

If you need any other pictures or that, let me know



Dave

Originally Posted by pipeclay

Is it possable to mount the scale directly to the table without the use of the Angle,if not I would think that you would need to use what ever material thickness would be best to eliminate Vibration and Resinance,these 2 factors could have a bearing on the accuracy of your Readout.

That is what has been done by whoever fitted the DRO to my mill... The scale for the X-axis is bolted directly to the BACK of the table, and the sensor is bolted directly to the saddle.

The Y- axis scale is bolted to the right hand side of the knee, and the sensor is mounted to the saddle via a bracket constructed of TEN MM plate! Seems like overkill to me, but it works I guess. It seems to have some kind of leveling screws installed into it as well, presumably for fine adjustments. Odd, as the plate seems to sit flush against the saddle anyway

However, my scales have an endcap on either end with a hole through them for the bolts, Stus scales don't seem to have that?

lol That thread should help me out. I'll have a read and have another look at my mill tomorrow. I'm pretty sure my T slot is higher up the side of the bed than yours

What are the black blocks for to the left and right of the X axis gib locks?

Stuart
They are the table travel stops. I modified the right one to be a table stop/cable clamp.

Jekyll
That is the standard factory way they fit the X axis scale, thats where it was originally fitted to this mill..
On my old mill I mounted the scale on the back but still use a 5mm angle to protect it. It wasn't enclosed like I did on this mill so I used the standard scale cover on it.
On my old mill I drooped a few thing over the back of the table and was glad the steel angle was their to protect it. I also once ran the table into the column when I was concentrating on something else, but again the table protected it.

With your Y axis, he must think the same as me,lol
I built my brackets out of 10mm steel contoured to suit the mill and angle over the scale as well, an overkill but again if they get hit they won't get damaged.
I think Stuarts scales will be the same with the hole in each end cap.

Dave

Dave I thought so but I could see anything that would press against them.

Jekyll my scales have hole on the ends, I forgot the pictures were so bad. I would like to put it on the front to save Y travel if I can(and I think I can do it without drilling as many hole.I will do some more checking tomorrow.

Stuart

Nvm Dave They are table stops, not "adjustable table stops", got it.
Stuart

They are the full table travel stops from factory, they contact the blocks on the ends of the table to stop to over running it.
There was no way I was going to be able to get the power feed limit switch under the scale so I built everything out wards so it would all fit. It worked out good because the scale and reader head are fully protected from abuse and coolant.
The flat bar I enclosed the scale in with is 6mm thick and protects the scale from knocks from the front as well as giving extra strength to the angle. I use the belt sander to remove the scale and polish the top and back of the angle and also the flat bar. It also saves trying to fit the standard scale cover under the angle.
I was hoping to get away with only one hole in the table, but after trying it with a clamp I found it would be better with 2.

Dave

Yeah I worked that out reading your thread.
Mine doesn't have stops like that. One end has a bolt in the T slot so the power feed stop cant only go so far. The other end winds in until the handle hits the Y axis gib lock. I'd like include an adjustable table stop as part of the powerfeed stop(maybe not really needed with a DRO). I many need to bring the angle iron 10mm off the table to make it work.
I'll try and get some angle tomorrow so I can show you guys what I have in mind. I think I can get 50x50 in 6mm, I''ll go for that if I can.
Stuart

Well I bought two 1300mm lengths of angle iron today 50x50x6 and 65x65x5 the 5mm turns out to be more like 4.5mm. So I'm going to use the 50x50.

To still be able to use the stop T slot I'm going to bring the angle iron forward from the bed by about 12mm. The bed is about 300mm longer than the scale so I have 150mm of support each end. Pretty hard to draw in paint Put I'll just see how it goes as I dont need to drill any holes in the bed to try it.
So the first thing I need to make is a couple of 150mm long T nuts and matching plates to go between the bed and the angle iron.

I might even try making them on the shaper so they are nice and flat... I need all the practice I can get hehe..
Stuart

Hi Stuart,
From the looks of it your table is thinner than mine, working out mine took a long time, a heap of measuring and a lot of dummy set up's.
Another option I looked at while designing mine was to put a aluminum T slot track on the front of the enclosed angle. That way their was no need to worry about the original track in the table.
I was lucky that I had room so I didn't need it, but it might work for you. It would make adjusting the stops easier and still have the full length to slide them along.
The aluminum place sell all sorts of track for boats, trucks, etc to pick from.

Dave

Great idea Dave. I'll keep going with my idea for the minute as when it turns out that it sucks, I'll easliy be able to switch over to you idea.

The biggest worry about the way I'm doing it at the minute is just how much trouble swarf going into the gap could be.

So far today I've cut to 155mm lengths of 25x 10 bar and set them up in the mill. Its a slow day lol

Stuart

I think the table is about the same thickness. 70mm
The bottom of the 10mm opening of the T slot is 25mm from the bottom of the table.
So its still possible I'll be able to do something pretty close to what you have done. I'll get the angle bolted on and then have another look.

I took my inspiration for mounting my X-axis scale on a HM-52G from Dave's excellent work/idea, which he has linked to previously in this thread. My mill has a different type of power feed arrangement to Dave's, and that is one of two things I havent completed so far - the mount for the powerfeed switch and a splash guard that will mount to the X-axis reader mount, and extend up behind the X-axis front cover.

I had a few options with the Y-axis, but I decided on one that needed a largish mounting block to bring the front of the knee to the same width as the mating surfaces of the Z-axis. The photos of the Y-axis show this red block under the front of the scale/cover. I also utilised the mounting bar that was supplied with the scale - it is supplied with 4 socket head grub screws - one at each corner - to enable levelling in all 3 axis. While I had my machine apart I installed new chip guards in the Y-axis which has extended the Y-axis travel to 240mm, with nothing more than some work with tin snips, 5" grinder and a file. Another of Dave's ideas, but I decided not to add a block to the front of the knee to increase movement as my scale is only a 250mm.

For the Z-axis, I needed to create a block that allowed for the tapering of the column at the top, and a mount for the first of three right angle brackets that transfer motion to the reader head. I used the same layout for this mount that the scale mounting bars use - 4 socket head grub screws to enable levelling in all 3 axis. For the scale body I again utilised a scale mounting bar to enable levelling.

The placement of the DROs on H&Fs machines didnt look too convenient to me, so I made a pivoting offset arm that allows the DRO to swivel to a lot more positions, and can be lifted off in 5 secs if need be. It still utilises the original DRO arm, in addition to the offset arm.

If you want anymore photos to illustrate something, give me a yell.