8” Pratt Burnerd 3 jaw on a 1440 lathe

[lxcnc]

I bought an Eisen 1440E lathe (Taiwan made) a few months ago. I’ve been researching chucks, and I happened to find a good deal for what I was looking for on eBay.

I found a Pratt Burnerd forged, adjustable “Setrite” 3 jaw chuck, 8-1/4” with a d1-4 backplate, for $500 - it’s like new. I adjusted it to within .0005” using a ground rod. I am amazed at the difference in repeatability between this and the 6” Chinese chuck I was using.
A 50 pound chuck isn’t too heavy for a solid 1440 lathe is it? I definitely notice a difference in the time to spin up to speed. The lathe came with a 2HP single phase motor. I’m switching it to a 3 phase with VFD soon, won’t this help with the spin-up?

 

[pstemari]

You lucky dog!

That looks like the perfect chuck for that lathe.

Sent from my Pixel XL using Tapatalk

 

[lxcnc]

Thanks! I have had a lot of luck on eBay lately. I found an Aloris BXA tool post with 3 Aloris tool holders for $50! I had to take it apart and clean out years of chips, but it works like new now.

 

[Tozguy]

Why is the Serial No. blacked out in the picture?

 

[Firestopper]

That chuck is not too big for your machine. The rotating mass is beneficial for stable cutting. On your motor, single phase will always struggle vs 3 phase. Your 1440 should have a minimum 3 HP motor when you convert it to 3 ph. You'll love it and it will be easier on you electric bill in the long run. Ebay deals aren't as good as they once where, but if your persistent youll score. Nice chuck BTW.

Paco

 

[mksj]

Great score, I have the 6.3" PBA on my 1340GT, Bill has the 8" PBA. Quality wise they are up at the top of the heap for a manual chuck. The Setrites will repeat to better than 0.0004" with repeat clamping, which makes them great when a part is in/out of the chuck for multiple operations. Two things that I have found on my PBA worth noting, when you reverse the jaws be careful that they set properly and recheck the TIR each time they are reversed. The second aspect is the jaw tips are a bit narrow, so holding small round stock will often push out/wobble between the jaws. A collet system works better on smaller stock.

Agree with Paco, if you go to 3 phase/VFD in a 1440 size lathe I would opt for a 3Hp motor. Often you need to go with a TENV type inverter rated motor because of space constraints. You would want to program a ramp up acceleration on the VFD, something like 3-5 seconds. Braking wise, you will need a braking resistor and you have a lot of momentum in the chucks, I would recommend a 3 second braking time.

 

[wrmiller]

I bought an Eisen 1440E lathe (Taiwan made) a few months ago. I’ve been researching chucks, and I happened to find a good deal for what I was looking for on eBay.

I found a Pratt Burnerd forged, adjustable “Setrite” 3 jaw chuck, 8-1/4” with a d1-4 backplate, for $500 - it’s like new. I adjusted it to within .0005” using a ground rod. I am amazed at the difference in repeatability between this and the 6” Chinese chuck I was using.
A 50 pound chuck isn’t too heavy for a solid 1440 lathe is it? I definitely notice a difference in the time to spin up to speed. The lathe came with a 2HP single phase motor. I’m switching it to a 3 phase with VFD soon, won’t this help with the spin-up?
View attachment 255958

Dude, you stole that chuck!

As Mark said, I have the 8 1/4" PBA setrite on my 1340GT and after checking with Matt to make sure my spindle was stout enough (it is) to support it. It's been on the lathe since day one, and I've had zero issues with it. As you've discovered, it is a high-quality chuck that repeats like there's no tomorrow.

I have a VFD on my 1340GT, along with one of Marks super-duper control systems w/threading stop, and the soft start function of the VFD works really well at spinning this bad-boy up. I also have a three position spin-down function with one setting being <1 sec, another one at 3 sec., and the third is a combination of the two. I don't have a foot brake and the longer spin down is needed when spinning at 2k rpm as it's a lot of mass to try and stop at that speed!

Also, as Mark pointed out, there are better ways to grab smaller stock. I have a ER32 chuck with a 1" diameter stud that I stick in the PBA and true in for smaller stuff. But I'm in the process of getting a TMX set-tru 5c collet chuck and a 35 piece collet set for working with the smaller stuff, because it makes working with the small stuff a bit easier, and the fact that I get a bit nervous working up real close to this chuck when I'm spinning the heck out of it. This is the biggest chuck I've ever had, and it can be a bit intimidating at max speed and I'm trying to work right next to it!

 

[lxcnc]

Why is the Serial No. blacked out in the picture?

It’s not because of members here. I’ve seen where people search photos on the Internet to use in scams, such a as a bogus auction, or even re-use the serial number on a fake product.