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

Pierre and Bob

SUCCESS! :courage:

After quite a few hours of perseverance I am pleased to report that I now have 1 thou in 5 1/2" (length of my unsupported alloy turning bar) taper.

So, I will be content with that. Trying to attain perfection would be an exercise in futility!

The printer rod was a huge help in that it gave me a reliable reference. Due to the spiral mark from the sponge coating, which was not going to come off without being aggressive, I chose 2 reference points and retracted the dial indicator probe when moving back and forth between the 2. It can be done accurately if you are gentle. The reduced diameter RHS end gave me a handy cross-check that the bar hadn't deflected with all the dial indicator probing that happened countless times today as I could gently revolve the chuck by hand and verify the runout had not altered.

It was a very frustrating experience due to the spring in the headstock. In the end I put a washer under the cap screw closest to the operator. This helped reduce the spring/unpredictable movement effect. Until I did that, I was on a hiding to nowhere!

Initially the other 3 cap screws were also having an effect on the spring back too, but after much moving of the headstock left to right whatever was causing the issue with them disappeared from the equation and it was just the front right cap screw that was the problem.

But I was still faced with 40 or so thou spring when backing the screw off to move the headstock. I discovered that if I left the other 3 loose and cinched down this one (front right) all the way I could then predict the end reading give or take a couple of thous, so had to keep at it until is landed at the the desired tolerance. Then a case of gently cinching up the other 3 in a regimented order every time. Bit like doing up the wheel nuts on your car in that set pattern.

Running between centres was not so successful as I have a 14 thou runout even after re-zeroing the tailstock using the razor blade method and a freshly turned centre point in the 3 jaw chuck.
The live centre point does not seem quite right - I think it is giving me a false zero - I need to take a very close look at it and even with 2 pairs of magnifying glasses on I can't focus on it - the joys of getting older!
So will need to find a magnifying glass.

I knew that bedding down a lathe was a precise affair but never imagined it could by this finicky. However, I do think there is a back story to the history of this lathe that I will probably never know.
Congratulations!

I've been following this thread with curiosity. You've been getting great advice from obvious experts, and it's been a real education to me.

Hope you enjoy using your now-functional lathe.

Regards,
Terry
 
Terry

Thanks. It has certainly been a learning experience, the path put before me by Bob and Pierre has undoubtedly helped a great deal. I won't call any of this "easy", but without their help it would have been much more prolonged and I would have had to discover for myself (the repetitive way) how to solve the problems by trial and error - probably lots of errors...... Without their help I most certainly would have not had the correct order to tackle the taper problem.
I had believed it was a bed twist due to an out of level issue, rather than the headstock alignment it actually was. This was from reading lots of "how to" information on the internet which almost all fixates on levelling to be the crucial issue for a lathe. I know now that it is just one factor and to paraphrase Bob, "it is a starting point, just get it reasonably level, then move on to the other adjustments that could have been fiddled with at some
time in your lathe's past".
For sure, the worst issue for me has been that spring back when trying to aim the headstock. Until such time as I worked out how to deal with those cap screws that hold down the headstock and a method of allowing for the movement when they were tightened cost me many hours.

Regards
Doug.
 
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Bob, thanks.

Wondered what happened to you. Thought I would give it a bit longer before getting worried.

A good training job for me will be to make the height setting devices that go on the quick change tool holders.
For some bizarre reason, all 4 of my ones are missing.

On 2 of the holders there is a running thread with an allen key recess, but no cap screw head. These look too short to me to do the job as there would not be enough thread to project above the height device for a back nut to lock it.
On the other 2 the running thread is missing altogether along with 2 square head cap screws on each holder.

See here for what I assume they should look like.
<http://www.bison-bial.com/spare-parts-and-accessories/u-6876/0>
Why buy them when I have a lathe and can make them!

So, do you have any idea of how tight a fit the skirt on them is in the 2 cam like fingers that rotate out from the head?
<https://www.cromwell.co.uk/shop/spi...ts/t-00m-quick-change-toolpo-st/p/IND4454800K>
I would assume that they don't have to be a tight fit, because the lower finger would support the skirt, but, there is an upper finger and I doubt it is there for decoration?

Also, I went all over the QCT head trying to find any markings at all. There are none, likewise on the tool holders. You asked me about that quite a while back and I did not get to check it out till today.

Regards
Doug

Doug you have listed two different brands. There are quite a few of this design made by different companies in Europe, and they are not all interchangeable, so be careful. I'll have to dig mine out, it's a different brand again, I'll try to get some dimensions, and maye a pic or two The two flanges are actually on a helix and work like a cam, You would have to make them out of some pretty tough steel because they are hardened, A piece of axle steel would be good.

Send me a pic of yours so I can see what is missing, also note what the threads are, because I reckon I can get spares of some of the parts, if they are the same as mine.
 
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Bob.

I will get some photos tomorrow. I need to see if I can find some regular axle steel. That huge 2 1/2" inch dia one I have is almost mild steel in the centre so will not be suitable.

I realised I showed 2 different brands, that was just for quick reference. However I have no idea of what the correct version for mine would be. Chances are it came from Paramount Browns or Modern Tools(?) in Adelaide.

Regards
Doug.
 
Bob. In the meantime, here is a photo I just found of one of the tool holders. I note there is a letter stamped on the inner face. Hopefully there is more and it will mean something.
20180617_164703.jpg


Here is the normal view (with that SECO tip holder).
20180620_134735.jpg


Although I am clicking on "full image" for some reason this forum is displaying the photos in reduced size, so you cannot see the markings in the first photo.

Doug
 
Doug,
it may have although I have not seen that style in either shop, but that don't mean they haven't got them or maybe used to have them. If it is unbranded then maybe its a cheap chinese knockoff that is no longer around. They seem to have all gone to the Aloris style, which is much easier to get and a lot cheaper.

that larger dia shaft you have maybe soft in the middle but it will still be tough, and you can always heat treat it after machining, but it might be easier to get a smaller dia one from a car mechanic.

This appears to be a chinese knockoff of the American Aloris, which is what I have, quite happy with it. The genuine Aloris is about 50 to 80% dearer depends on any specials at the time. Note that your style tool post and holders cannot mixed with Aloris type, they are totally incompatible.

It is much easier to get spare tool holders and other parts for the Aloris type, they are also a simpler design making them more suitable to be made at home, although you do really need a milling machine or a shaper. Or milling capability on the lathe as I'm working on , but it will be while yet.
 
Bob. In the meantime, here is a photo I just found of one of the tool holders. I note there is a letter stamped on the inner face. Hopefully there is more and it will mean something.
View attachment 270826

Here is the normal view (with that SECO tip holder).
View attachment 270827

Although I am clicking on "full image" for some reason this forum is displaying the photos in reduced size, so you cannot see the markings in the first photo.

Doug

I ntice in that second photo that the tool is not setup correctly, you should loosen the 3 clamping screws and slide the tool to the right so that the back end is fully under the last screw, the way it is, it's not clamping correctly, it even looks as if that last screw is bent from using it this way.

Also how are you lockingh the tool holder onto the tool post without the clamping piece.
 
Bob

I noticed that and corrected it.

Because the height stop is missing, I have to set the tip height to the live centre point each time I change tools. It is a nuisance for sure.

Doug
 
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