[How-To] Tips for removing a stubborn lathe apron

[keeena]

I'm having a hard time getting my lathe's apron removed from the carriage. As far as I can tell its only attached with the 4 SHCS thru the carriage. The dowel pins (may be tapered?) are visible in the top of the carriage. I've got the apron to a point where it does wiggle a little bit, but that's it. I've done some moderate tapping thru the heads of the 4 bolts, but apron refuses to budge. I don't want to really give the bolts the BFH; feel like I'd break something.

All the control rods are removed, cross slide removed, etc. Nothing else appears to be holding it other than the 2 dowels.

Any tips?

 

[bulgie]

I'm having a hard time getting my lathe's apron removed from the carriage. As far as I can tell its only attached with the 4 SHCS thru the carriage. The dowel pins (may be tapered?) are visible in the top of the carriage. I've got the apron to a point where it does wiggle a little bit, but that's it. I've done some moderate tapping thru the heads of the 4 bolts, but apron refuses to budge. I don't want to really give the bolts the BFH; feel like I'd break something.

All the control rods are removed, cross slide removed, etc. Nothing else appears to be holding it other than the 2 dowels.

Any tips?

Heat gun?

 

[keeena]

Heat gun?

On what part? The apron itself or the heads of the tapered pins?

 

[woodchucker]

your rods are all removed?
Your carriage lock is removed? (sometimes threads through apron)
what kind of lathe? pics to see what you have going on?

 

[Pevehouse]

Pictures would really be good in a situation like this. I have my apron off and tore down right now

 

[bulgie]

On what part? The apron itself or the heads of the tapered pins?

Well every job is different, would prefer to have more info and pics, but in general you want the heat on the part that loosens its fit as it thermally expands. Sometimes that's obvious, like a steel part stuck in aluminum, definitely heat the Al, since it has a higher thermal expansion coefficient. If it's an Al part stuck in steel, heat will make the fit even tighter, so it's not as helpful. (These are general examples, I know there's no aluminum in your apron.)

If you can't heat just that part (the one that fits looser as it expands), generally heating everything often helps too, in a couple different ways. Sometimes repeated cycles of heating and chilling will get you some movement, can help the penetrating oil penetrate.

Do the tap-tap-tap to knock things loose while it's still hot.

It's not a panacea, but it's one of the arrows in your quiver.

 

[keeena]

Yeah, I didn't include pics initially because apron-saddle assembly is typically a pretty standard design: just a few bolts and dowels/taper pins thru the saddle down into the apron. But you're right - never hurts to have pics.

In any event: problem solved. I used a mini-sledge (5lbs / 2.3kg) on the SHCH heads and the extra mass/shock did the trick. Didn't require any swing per se; just let the hammer drop from increasing height. I made sure I had nearly fully thread engagement to spread the load and help avoid damaging. Before this I started w/ a soft-faced dead blow, then a 2lb brass hammer.

Probably should have mentioned the lathe is about 40 years old. Cutting oil that had wept into the taper pins and then dried up is what really caused this sucker to stick.

 

[Pevehouse]

Glad to hear you got her off

 

[woodchucker]

The pics would have been to see if you were overlooking something, and to give us a clearer pic of what was going on.
Everyone can and has missed something at some point in their life, that head smacker..
Glad you got it out.