Oxa 000 qctp fit my 6" craftsman?

[ROY@ESUACE]

Hi all:
Roy from Maryland, USA here. I'm an inexperienced lathe owner(Craftsman 6") but dream of building an IC engine some day. I'd like to get a QCTP for my lathe but the two OXA series 000s listed on LMS says you need 5/8" from compound to spindle center on one ad and 3/4" on another for the OXA 000. One is listed as TORMACH, and the other is not named, but the ads look the same. SEE #3048 on http://www.littlemachineshop.com/info/qctp.php Here's my question - I measure 17/32" from the top of my compound to the dead center point in my spindle. Can I use the OXA and just set the tool holders a little lower on the post, or does this cause some other problem? I like OXA because it's steel, and wedge-locked, not plunger. There is a T6 aluminum one offered by LMS, but the OXA, though a little more money, looks like a better deal.

Thanks in advance for your help
Roy

 

[Tin Falcon]

Do you have the craftman atlas or the dunlap.
what model no. ?
Tin

 

[Tin Falcon]

IMHO a qctp is a great and almost necessary first upgrade to a lathe.

I would need to look at the dimensions of the OXA .
I can tell you the distance from the top of a 1/4 bit to the bottom of an A@Z tool holder is .425. you can only lower a qc holder so much before it bottoms out. you can use a smaller bit like 3/16 for some adjustment. and you can always make a shim to raise the tool post.
seems like a oxa woulsd work but not totaly sure.
what part of maryland are you from.
Tin

 

[Rex]

Far as I know the 3048 is an Asian copy of the A2Z. I can't imagine why the minimum too height is different.
But I'd email or call Chris Wood at LMS and ask him directly. Nice guy, and very sharp.

 

[ROY@ESUACE]

Hi Tin/Rex:
Sorry to be so long answering, I've been out of town a few days.

Tin- I am from near Hagerstown, MD, in the mountainous, narrow part of the state. I have the Sears operating instructions & parts manual for my yard-sale find from about 35 years ago, showing model # 109-21270 on the cover. I just looked and the number on the serial plate is also 109-21270.

I guess my QCTP confusion comes in when I read "Minimum compound-to-spindle height is 3/4" for the 3048 and I only have 17/32". Is my 1/4" tool going to be too high on the QCTP to get on center on my lathe? That's what it looks like to me. I was thinking that I could make up the difference by lowering the tool holder on the post, but Tin, I think I see what you are getting at, the OXA holder may bottom out on the compound before I'm on center with he tool, where the A@Z would have .106 to spare at .425.

I just re-read the info on LMS website, it does look like the one I wanted is not recommended for mini's. The piston & T6 alum construction is the one I will probably go with. I just thought the wedge design, steel construction, and knurling tool included was worth the extra $30 with the OXA.

I don't really want to switch to 3/16" tools because I got about 20 - 1/4" tools with the lathe, and would like to possibly buy a set of "store-bought" tools some day. I never see 3/16 sets advertised. I do have a few 3/16" tool steel blanks if I had to make smaller tools.

Rex: I sent an e-mail to info at LMS to see what they have to say about using the 3048 with my mini.

Here's some more info about my lathe adventure:
With the lathe I got a face plate, lantern style TP, 4 jaw chuck, 2-#0 dead centers, a Jacobs 33 drill chuck, complete set of change gears, and the lathe was mounted on a table-top with motor & switch. I've made a dog for the face plate and tried my hand at threading(unsuccessfully) and grinding a few tools. I've tinkered around and made a few parts over the years, but have gotten more interested after lurking on HMEM for awhile now.

I have had a set of plans for an engine for some time, just never got started on it. Before finding HMEM I didn't know enough, and I still don't know much , but I think I'm learning enough to at least get rolling. Having no time because of too many other hobbies, and my honey-do list are other reasons for not tackling the engine.

Enough rambing. Thanks for your responses - I'll keep you posted on what LMS says.

Roy

 

[ronboult]

Hi Roy

I have a Tormach OXA QCTP ( from LMS) fitted to my Sieg SC4 lathe.
The standard Tool holder for this QCTP is labelled 250-001 and measures roughly 0.162" from the bottom of the holder to the bottom of the groove which holds the tool.

This means that with a 1/4' tool bit the minimum height from the top of the Cross Slide to lathe centre is 0.25 + 0.162 =0.412" With this minimum dimension you would not be able to lower the tool bit any further. If the distance is greater you may be able to use bigger bits. The 250-100 tool holders will accept 1/2" tools

I have many 260-100 holders and the 0.162 dimension varies from 0.146 to 0.162 on my different holders.

For what it is worth I originally fitted a A2Z Aluminium Piston QCTP ( from LMS) but have now changed to the Tormach OXA and find it much more rigid. I use 12mm cutting tools so I am not sure if you would notice the difference with 1/4' cutting tools.
Hope this helps
Ron

 

[Tin Falcon]

Roy :
OK you have the Dunlap version of the Craftsman. AKA the 109 these are not the most loved and easy to use machines but with some patience and perseverance I have seen nice stuff made on then. I have one like yours and another variant as well.

IIRC some of the Sherline tools will fit on it and this guy supports them as well .

http://www.homeshopsupply.com/upgrades.html

there are sites out there where guys have fixed these up and or upgraded then.

knurling tool included was worth the extra $30 with the OXA.

Maybe not. Plunge knurling puts a lot of force on the head stock even a short piece supported buy a dead center. The head-stock spindle on the 109 is pretty small . I would not use or recommend using a plunge knurl on a 109 you will likely bend the head stock spindle. if you want to knurl buy or make a scissors knurl the forces are much more isolated to the tool.

Photo from LMS plans available from LMS

As far as choice either the OXA or the A2Z should work on the 109. the OXA is no doubt better as it is made of steel and it is wedge style rather than piston. I do have a A2Z and like it and I like the fact it is american made. So always trade offs and choices.
Tin

 

[ROY@ESUACE]

Hi Ron:
Thanks for the response. This gives me hope that the oxa will work on my lathe. The cutoff blade holder will not work unless I want to adapt a blade shorter than 1/2" because my compound-to-center dimension is .527", just under 17/64". I would still probably buy the oxa post, even if the cutoff holder may not work. I see tormach cut off tool holder # 250-007 (See http://www.littlemachineshop.com/products/product_view.php?ProductID=3774&category= ) is angled UP (I assume) at 4 degrees. I could possibly use it backward, angling a reground blade DOWN 4 degrees. Anyway, I think I would go with oxa if this is the only downside. Do you know a dimension on the center between the wheels on the knurling tool?
Cheers,
Roy

 

[Tin Falcon]

Looking a bit more looks like the tor mach 3112 or the axa are the choices you have the other one has thicker tool dimension on the bottom of the tool holder.
tin

 

[ronboult]

Hi Roy
Sorry but i did not buy the tormach knurling tool.
LMS swapped it out of the kit for me & replaced it with another straight tool holder. You can't have too many straight holders(250-001)

I would suggest a scissors knurling tool as recommended above for the same reasons
Ron