Hafco AL900A lathe, is anyone able to identify what it really is?

Hello all. I have made some progress over the weekend along with other jobs.

I made up a "peep sight" to align the head with the tailstock live centre point. I used a piece of 23mm idiameter alloy roughly 3" long cut off the 11" bar from earlier on. Bored it out with a 1/8" drill bit. I knew that I had a piece of alloy that was an offcut from one of my Dad's jobs 3 decades ago, so went and fished that out. Other than the hole being a bit big, it was a lovely fit as was into the spindle. You have to win some!
So inserted some alloy sheet metal and drilled it to 1/8".
Sighting through the plug, then through the the bar, allowed me to aim the headstock at the centre point. The peep sight concept meant I could move to and thro and forward and back until the various circles touched each other and gave the desired accuracy. I did need to black the centre and then highlight the last 5mm of the point with white paint. I also need to black the plug, but even then reflections made a nuisance of themselves so hung a cardboard box over it as a hood.
See photos.
20180623_140431a.jpg

20180623_120700a.jpg


The headstock was aligned as best I could, then verified by my wife and a friend who dropped by.

The other job today was to pull the 4 jaw and 3 jaw chucks apart and clean them out. Multiple
reasons, one is Bob insisting I do it, the other because the 3 jaw had a noticable tight spot
about mid jaw movement. But mainly it was so I could clean out what I suspected was a swathe
reservoir between the mounting plate and the chuck proper.

- 4 jaw - removed cap screws, but cannot separate it. Any suggestions? Don't want to force
anything into the gap as don't want to risk burring mating faces.

- 3 jaw - came apart very nicely. See photo for what awaited me. After cleaning everything up,
I greased it with graphited grease and reassembled. Now that the swathe reservoir is empty,
there was no issue with screwing it back onto the spindle. This proved itself when I did a test
cut on the bar and the runout of the work is 1 thou.
The runout of the back plate and chuck are both 4 thou, the same as before disassembly and
cleaning, looks like nothing can be done about that.
20180624_151559a.jpg

Now to the swathe reservoir - what a dumb design! My first thought is to put a bead of silastic in there. Does mean that it must be cleaned off next
time chuck is pulled down and will make doing so difficult, but it will stop the swathe collecting in there and then constantly finding its way into the chuck inards: but mostly stop it finding its way onto the spindle thread every time I screw the chuck back on. I did consider an O ring, but the natural curve of the ring will still allow fine swathe to build in that area.
Does anyone have any other suggestions what I could use that will compress easily and block that area off?

Regards
Doug
 
Was the 4 thou runout on the backplate after cleaning etc and measured by itself? You can take a skim cut on the back plate to return the run out to zero. When one buys a back plate for a chuck, it a first step to fit the new plate, even a fully finished one.

As for splitting the 4 jaw, loosen the bolts again a couple turns and tap on the heads to push the chuck off.

See here. https://www.hobby-machinist.com/thr...ed-spindle-backing-plates-for-my-lathe.19802/
 
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Pierre

Further cleaning and work today.

I pulled the back plate off the 3 jaw chuck and installed an O ring to seal the swathe reservoir. Failed to notice the alignment mark on the back plate so had to do the process a 2nd time when the chuck runout was 7 thou.

I now have the backplate and 3 jaw chuck both at 1 thou runout. Very happy with that.
So no need to machine the backing plate.
Thanks for the link.

Running a 19mm alloy bar between 3 jaw chuck and live centre in tail stock I am getting 30 thou taper over 200mm. Adjusting the leveling legs
seems to be an exercise in futility.............

Regards
Doug
 
Pierre

Further cleaning and work today.

I pulled the back plate off the 3 jaw chuck and installed an O ring to seal the swathe reservoir. Failed to notice the alignment mark on the back plate so had to do the process a 2nd time when the chuck runout was 7 thou.

I now have the backplate and 3 jaw chuck both at 1 thou runout. Very happy with that.
So no need to machine the backing plate.
Thanks for the link.

Running a 19mm alloy bar between 3 jaw chuck and live centre in tail stock I am getting 30 thou taper over 200mm. Adjusting the leveling legs
seems to be an exercise in futility.............

Regards
Doug

Doug some progress, but still problems, welcome to the world of hobby machinist with a preloved machine. I take it you have squared your headstock and that is turning without taper.

The next step is to adjust the tailstock. You should find an adjustment where you can slide the top part of the tailstock across sideways. Can you post a couple of pics of your tailstock good close ups from front and RH end. so we can see how it's put together leave your levelling screws where you feel they are near correct for now.

Slide the tail stock up to the headstock with a center in each. you will see they are not lined up, so we have to adjust that. Let me know if you want me to call.
 
Bob

I have the tailstock and headstock aligned (well, I think I have), but this taper thing is getting really vexing.

It is apparent that fiddling with the leveling feet is not working. so am assuming I need to go back to basics. Your point about centre to centre is
worth trying, however, I have no way of putting a centre in the headstock that I am aware of. Besides that, the spindle hole is 1 1/2" I.d. which would be a pretty huge Morse taper?

All that I can think of is to cut a point on a piece of short bar in the 3 jaw chuck?

Regards
Doug
 
Bob

I have the tailstock and headstock aligned (well, I think I have), but this taper thing is getting really vexing.

It is apparent that fiddling with the leveling feet is not working. so am assuming I need to go back to basics. Your point about centre to centre is
worth trying, however, I have no way of putting a centre in the headstock that I am aware of. Besides that, the spindle hole is 1 1/2" I.d. which would be a pretty huge Morse taper?

All that I can think of is to cut a point on a piece of short bar in the 3 jaw chuck?

Regards
Doug
Exactly put a piece of scrap in the chuck ,machine a center point on it and slide the tailstock up to it I bet they don't line up. BTW the headstock should be a #4 or 5 MT.
 
Exactly put a piece of scrap in the chuck ,machine a center point on it and slide the tailstock up to it I bet they don't line up. BTW the headstock should be a #4 or 5 MT.

If adjusting the leveling feet isn't fixing it then obviously it's something else. My bet is the tailstock. the previous owner may have set it over for special job and never put it back.
 
Bob, will do, hopefully tomorrow.

The tailstock is adjusted exactly even. I will be surprised if it is the problem, but as I am out of clues, I will investigate that.

Doug
 
Bob, will do, hopefully tomorrow.

The tailstock is adjusted exactly even. I will be surprised if it is the problem, but as I am out of clues, I will investigate that.

Doug

Doug, if as you say, the tailstock is adjusted exactly even, what was it aligned too, how do you know it's correct. the problem you have is exactly what happens when it's not adjusted correctly. the standard method of turning a taper is to adjust the tailstock over. The little mark on the end is usually as useful as t*ts on a bull. I've never seen one that was correct.
 
Bob. I have adjusted the headstock with my peep sight arrangement post #141 from how it came, so am concerned that if I now fiddle with something else (tailstock), I will have altered a 3rd setting that was possibly factory. Given that the leveling is a an exercise in failure I need to try something else. But this will introduce yet another unknown.
1) Leveling
2) Headstock
3) Tailstock

If the tailstock adjustment fails then I will have a lathe with no possible factory reference parameters left.

Then what do I do?

Regards
Doug
 
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