Orac Programmed from Laptop & Associated Wiring Connections.

[TDIPower]

You have spent money.... No turning back now!!!

Pete

[Ridgeback]

Hi Pete,

Oh Blast, thought nobody would notice that little slip up. Perhaps you are right, no going back now as I will have to explain to the other half why I spent £2.49 for nothing. Can't have that now.

The plug taper gauge I was making for checking the spindle back plate taper, is now complete. Just need to measure it up, make some drawings and get it on the site for others to copy and use. My idea was to machine the back plate taper, using my Boxford lathe and then use the plug gauge to check it stage by stage. If I over do the taper depth, it can be put right simply by machining a bit off the front face to bring it back again. All this can be done without the need to remove it from the machine. I can't see too many issues with this idea so hence the reason for pushing forward with it. Once complete, it can be attached to the Orac spindle to machine the chuck register in situ to avoid any run-out problems if it was to be done elsewhere. My new (to me) chuck will be bolted onto the back plate via cap screws, through the chuck body from the front. Very simple.

All this is mechanical, something I am comfortable with. The pain will begin when the Laptop/Orac coms kick in!!! Can't Wait, NOT!!!

Cheers Colin.

[TDIPower]

I've got lots of 'projects' on the go but all thwarted by trying to recover from shoulder surgery a few weeks ago. Hospital appointments, physio, pain killers, frustration at limited movement/ability, having to do everything wrong handed and taking so much longer than it should. Hence having the time to spend on here and thinking about stuff.

Pete

[DavidB]

Ridgeback,

What gap are you aiming for between the chuck backplate and Orac taper when just placed on. I noticed with the D1-4 camlock on my Harrison M300 that it is maybe 0.1mm, I did check with a feeler gauge but can't remember, but even the cheap ones matched the more expensive closely. What I noticed was that my Orac had about 0.5mm clearance and while it could be pulled back it seemed excessively tight on the nuts to do so and as the design is basically the same I think my chuck mount is slightly on the small side. As far as I know the taper is just to centralise the chuck and the alignment is down to the faces meeting. The basic taper works out at 1:4 on diameter IIRC so that makes setting up fairly easy if you have a DRO and DTI.

[triac]

Colin

Old Machine Software ZIP file, open ORAC file and if DOS will work in your system or with DOSBOX downloaded you will be able to write programs and download to and receive programs from the lathe. Works for me in WinXP OK.

[attachment=0]OLD_MACHINE_SOFTWARE.zip[/attachment]

This file was downloaded from this site some years ago but I cannot find it on site now.

Emgee

[DavidB]

Triac,

Thanks for that, I hadn't seen it before so it might prove useful. I'll try it on my XP system and in all likelihood I'll be able to run it on my Linux system if I can figure the configuration as there are Windows and DOS support programs. I just checked the data plate on my Orac and it is late 1985 so should work with the software according to the readme file.

[Ridgeback]

Hi Guys,

Thanks for the messages and tips which are coming thick and fast. I am still waiting on the 9 Pin plug arriving, so there is no movement in that department at the moment. I will get round to looking at the Zip File software when I am in a position to use it. My Orac is an 84 vintage with all the original internals, so I hope it too is compatible.

Pete, sorry to hear about your health woes, hope you get mended soon and are back in your "man cave" normalising once again.

Regarding the Chuck back plate, I shall explain.

I work on CNC milling machines for a living and they come in handy in more ways than you can imagine. I placed my original back plate on the table, taper facing upward. I clocked in the bore with a DTI and zeroed the X and Z datum's, the Z datum was as high up the tapered bore as was acceptable to get a good reading. I then moved the machine X axis in a -ve direction (away from the taper), followed by moving the Z axis down as far as was acceptable. I moved the X axis back against the taped until the DTI read Zero once again. I noted both the X and Z dimension changes and used these to calculate the internal taper of the back plate, off my machine. I achieved "about" 6 DEG 9 Min 42 Sec. I say "about", because I noticed that there was some "marking" to the inside of the back plate taper probably caused by the spindle nose taper digging into it on tightening. DavidB, I think you are correct when you say that the faces do not meet willingly, much pressure on the 3 studs must be applied to pull it home, hence the marking. What sort of gap, I do not know as I did not check when I removed it. I feel that this method is not too bright because it must be either a "perfect" fit or one which is a little tight, in order to get it to run true. A smidge over and it will not locate well, creating room for run out.

My game plan is to make what I believe to be a correct fit using the taper plug gauge I made, take it a little further and this will enable me to be able to grind the front face back a couple of thou at a time until I achieve the fit I feel is correct. I think my back plate reproduction is going to be a little "Heath Robinson" to begin with as I have this anomaly in the original back plate taper to deal with. All part of the enjoyment of being inventive though.

What was wrong with a simple 90 Deg vertical register on the spindle, then a matching recess in the back plate which anyone can replicate at home?

Well that is me done for now. I hope the above is of some benefit to those who read this. Pics and sizes of my Taper Gauge will be uploaded later in the week, for those who are interested.

Cheers Colin.

[Ridgeback]

Hi All,

You win some, you loose some!!!

I have finally got the lead made up, the new chuck mounting plate is nearing its final fitting and the "old machine software" zip file loaded to my old laptop.
I had the machine ON whilst tightening up the back plate, when, for no good reason the screen/display shut down and this was followed by the smell of something cooked. If it doesn't rain, it pours. However, I always look for a positive in all negatives and I think I have found it. Imagine my frustration if this had happened whilst trying out the new lead and download, I could have spent ages looking for something which would have turned out to be unrelated. I still have the problem to solve though as there is no display and a nasty smell. Haven't found the cause yet. I might be some time before I get back to trying out the program download to laptop.

The good news, re the chuck back plate, my plan has worked a treat. I managed to get a fit where I could "Wring" the plate onto the spindle taper and it will hold itself in place without studs. The gap between back plate and spindle flange turned out to be about 0.06 mm. If I want to increase this gap, I only have to grind/turn a measured amount off the face of the back plate. I will download some pics of the method I used, later as this could be of use to others.

Cheers Colin.

[Ridgeback]

Hi All,

Just tried loading Back plate pictures but seem to have been cut off. Will try again!! Phew, made it.

The 3 jaw chuck is the one I wish to use on the Orac as it has my homemade interchangeable soft jaws (I have 10 sets). This will give me a wide scope of usage as I can make up my own set of Outside jaws with this. If anyone wants pictures of these jaws as a copy to make your own, just say and I will post them on this site.

There is a picture of the taper plug gauge in the original back plate. I set the original back plate up in my Boxford lathe, set the compound slide up to run parallel with the taper in the back plate bore, then replaced the back plate with the plug gauge blank and turned the same taper onto this. It was a case of trial and error by taking a cut and trying the back plate to see how it was fitting. This was continued until the gauge fitted the original back plate perfectly. Now the new back plate was set up in the Boxford and the reverse procedure carried out until the gauge fitted the bore in the new back plate. It then only left for me to drill and tap the stud mounting holes and holes for the chuck.

I hope my description is understandable so others might undertake this too. It has been a success. The final operation is to machine the chuck mounting register whilst on the Orac so that it has the best chance of running "true" to the spindle.

Good luck to those who want to have a go.

Colin.