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

When I was an apprentice I was given the job of restoring an old lathe, and one thing we did, was when we got the tailstock squared in we put two tapered locating pins into it. So if you wanted to move it you had to remove the pins, and when you wanted it back square you lined up the pin holes, knocked the pins in and it was spot on.
 
Bob

Thanks for the offer. All understood. I will PM my phone number to you. Don't want it on public display as I just received a spam email from a Chinese Carbide insert maker. They could have got my details anywhere, but I have been here the most.

My builder's level has reset-able vials. I detest those ones that can't be adjusted after they have been knocked or dropped.

Somewhere, in a safe place but currently unknown I have a Gunner's Quadrant. Don't know the accuracy of it, but gunners talk in mils, so assume it is pretty good. If I could only find it.......

Regards
Doug
 
A gunner's quadrant, I've probably seen one, as I was in the Artillery for a couple of years, but i don't remember it. I was probably not on the need to know list, as I was just the grunt, actually the gun tractor driver, to the real artillery guys the drivers were the lowest of the low, not really gunners at all. Once the guns were delivered to a site and set up the drivers were just there to fetch and carry.

With your resettable level that's ok as long as you know how to do it properly and how to check it. I'll keep you number secret if you want to let me have it it's up to you
 
Bob.
Gunner's Quadrant is placed on the breech of the gun. Typically for a gun not normally used for indirect fire (artillery is normally indirect fire) such as tank gun firing at something it cannot see. Your normal artillery unit comes with all the fancy instruments already on the gun or with the gun command.

Not worried about keeping my number secret as such, I just don't want to be answering the phone to half of India or China trying to sell me stuff I don't want.

Am thinking of having a chat tomorrow evening?

Regards
Doug
 
Tomorrow evening should be fine, say after 8.00 i assume you are on sa time,

Yeh the guns we had were pretty good considering they were made during WWII 25 pounders known as 9 mile snipers. Yes they certainly were indirect fire. we would set up a target we could see because we certainly could not see the real target. The gun surveyors would lay out all sorts of triangles and used lots of trigonometry to calculate where the target was in relation to were we were. Most of the time it worked and we hit the target.
 
Decided today to pull the chuck off and make sure there was nothing between the rear face and the spindle front face. As a base line I set up the dial indicator and turned the chuck by hand. Runout is 12 thou, that seems way too much to me?
Then locked the headstock gears and removed the chuck.
There was some dents and burrs on the rear of the chuck so I cleaned those off with an oil stone. The spindle face looked nice as did its thread.

However, the same could not be said for the thread inside the chuck. A bit scary actually. There were burs impacted into the thread the whole way down along with some bad damage (missing material) in the middle of the thread run.

I am guessing this is what happens when someone changes the chuck and does not clean out swathe first.

See photos.
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Then remounted the chuck and retested with the dial indicator. Runout was identical at 12 thou.
I then put the alloy bar back in and decided (without much optimism) to try and turn the far end and measure the difference to the chuck end to establish how far skewed the headstock is. As predicted, the alloy bar is too thin and it chattered badly. Sigh.

I will have to come up with a way to sight the headstock to the bed. I am tending to think I will use the 11" alloy bar and align to the centre bore of
it with the live centre in the tailstock. This should get me pretty close, then using a fresh bar, repeat the process and fine tune.
Another option would be to put a small drill through say a 3" long bar in the chuck and then bore sight to the live centre in the tailstock.
 
Did you indicate the spindle face and the M5 taper on the inside of the spindle? See yellow lines pointing to where to check.
C5DEDDFB-5ACF-4626-92DA-60E84EFF40B7.jpeg


I would be hopeful and look at the chuck as the source of the problem. Some missing material in the threads is not that much of an issue as the chuck will register on the front face of the spindle. Remove the back plate from the chuck after checking the spindle and install it. Now check again the mounting surface for the chuck. Maybe the backing plate needs to be refaced for example.
 
Did you indicate the spindle face and the M5 taper on the inside of the spindle? See yellow lines pointing to where to check.
View attachment 270248


I would be hopeful and look at the chuck as the source of the problem. Some missing material in the threads is not that much of an issue as the chuck will register on the front face of the spindle. Remove the back plate from the chuck after checking the spindle and install it. Now check again the mounting surface for the chuck. Maybe the backing plate needs to be refaced for example.

Yes definitely indicate the spindle face and the taper bore. I hope they are OK because if not it would suggest a bent spindle. And that is not a good result.
 
Pierre

Thanks for the info.

No I have not indicated the spindle face or bore, so will do so.

I had a talk to Bob last night and he agrees with you that I should take the back plate from the chuck, install the back plate and measure the run out of the back plate then go from there.

Regards
Doug
 
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