Another Hendey Refurbish

[682bear]

This afternoon I began machining a t-slot nut to mount an Aloris CXA tool post onto the compound...



...and discovered an issue with the compound.

I was using guage blocks to measure how thick to make the lower part of the t-nut... and found that the bottom of the upper lip on both sides of the t-slot is worn in the middle... there is a .015- .020 'arch' worn under the lip...

The only way I can see to fix this is to disassemble the compund and set the top slide up on the milling machine and use a keyseat cutter to skim about .020" off the bottom of the t-slot lips. I'm not sure I really want to do that because it will weaken the lips... but if the t-nut is only contacting the lips on the corners, it not only will be more likely to break the corners off, but also will not allow the toolpost to have a solid, rigid mount.

So... I think I'll give it a try... maybe next week.

-Bear

 

[682bear]

Well... I went ahead and set the compound up and skimmed the bottom of the t-slot lips...



I took about .015 off the right side and .030 off the left... that gave me about 80% cleanup and both lips are now the same thickness... That should work fine.

-Bear

 

[682bear]

This afternoon I finished the t-slot nut...



I made it the full width of the compund so it would be supported the full width. The front lip has already been broken and repaired sometime in the past, so may be more easily broken now.

If it breaks again, I'll have to mill it out and replace it with a steel block, but I'd rather not have to do that.

-Bear

 

[682bear]

I just couldn't wait any longer... I manufactured some chips on the Hendey!

I turned a piece of aluminum... my 'test bar'... it was about a 5 ½" long cut, then measured both ends to check for taper.







It tapered about .0002" over 5 inches or so... I'll call that 'good enough'. I'm not working for NASA, anyway.

You may have noticed in the first picture that the live center is extended way outside the tailstock quill... that is because it left the factory with the Hendey standard 2 ½ morse taper.

2 ½ morse taper tooling is unobtainable now... most people with Hendeys open the quill up to MT3 so they can use modern tooling. I will probably do that.

-Bear

 

[FOMOGO]

Would definitely say that .0002 is close enough. Don't think many new machines would hit that mark over 5". Nice work. Mike

 

[Beckerkumm]

What do you get when you run something shorter, say 3" without the tailstock? I've found that i can correct with a tailstock to a few tenths in your example but without it I am generally running more like .001 over 3" unsupported due to wear in the bed. Dave

 

[Braeden P]

The problem with my lathe is that the tailstock can not be adjusted. Other than that it is pretty accurate (0.00005 runout) not bad for an 80 year old war machine.

 

[Beckerkumm]

I'm not even sure I can measure .00005 so I continue to be impressed with the old Hendey. Some old US lathes have a reputation for hard ways that stand up over time and use. Monarch is one and I'm guessing Hendey is similar. My Smart Brown bed is supposed to be hardened but I believe it is somewhat softer based on the wear I feel. I've been told that holbrook, another English lathe has a harder bed than the S and B. Dave

 

[682bear]

I'm not even sure I can measure .00005 so I continue to be impressed with the old Hendey. Some old US lathes have a reputation for hard ways that stand up over time and use. Monarch is one and I'm guessing Hendey is similar. My Smart Brown bed is supposed to be hardened but I believe it is somewhat softer based on the wear I feel. I've been told that holbrook, another English lathe has a harder bed than the S and B. Dave

I think Braeden was talking about his Hardinge...

This old Hendey was made in 1921, long before Hendey began hardening ways... they are not very hard, but are in excellent condition. I haven't tried to measure any wear that may be present, because, as the old saying goes 'The proof is in the pudding'... If it cuts accurately, I don't get too hung up on the amount of wear present.

My old South Bend has very noticeable wear on the ways and is still very capable of producing accurate parts.

If I get a few minutes today, I'll take a cut without the tailstock and let you know the results...

-Bear

 

[682bear]

I made a quick setup with a 1.125" piece of 1215 and made a cut a little over 3 inches long... just skimmed .010 off...

Here are the results...



1.1138...



1.1135...

About .0003" taper... I'm very surprised...

However, you may have noticed that the taper reversed itself unsupported. With the tailstock the taper is bigger on the end. Without the tailstock, the taper is smaller on the end... that is interesting.

Either way, I'm pleased with the results so far.

-Bear