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donf
01-01-2013, 03:19 PM
I have made some chips with my redone Boxford lathe and all is well except for one small problem.
On my 8x import lathe 4 way post a ” bit was just a hair under centerline, now with the Boxford the much nicer turret post is set up for 3/8” maybe 7/16”. I tried to cut the carbide tool holders down yesterday. It didn’t go well. I had an idea they were hardened, and I was right.
I have a Sieg X3 mill so first I tried a light fly cut with a Latrobe 5/16 bit… that would make it about ten cuts around before the edge would be gone. Then I tried a brand new MA2L 1/2 end mill. It actually did worse than the fly cutter and now I get to learn how to re-sharpen those too! Since I just did a partial hair line cut on the end of one tool, its usefulness hasn’t been hurt. My little x3 mill did not like the light cut on hardened steel either, even in the first few strokes with a sharp bit.
So am I being foolish trying to make some of the carbide tool holder’s work with the turret tool post? I know I could just buy a 3/8 carbide holder, but I have a large stash of Kennametal and Valenite tcmt tcgt 32.5x inserts that will not work with the store bought 3/8” holders.
I could just buy an import AXA tool holder and be done with the whole problem, as that would get the height down where ” would barley fit the center line. So far in my limited experience I haven’t seen a need for one though. I have a large amount of shims and it doesn’t take me that long to set a bit up. Being very inexperienced in machining, the whole “how in the … am I going to do this” on each project takes so much longer than any minor shimming will ever take. The Boxford turret post is a really nice and solid piece too, if it was just an import 4 way it would be an easy choice. I was thinking if I could somehow mill the carbide tool holders to set at center height without any shims that would be very nice. I have a bunch of 5/16 and 3/8 USA made HSS bits so I could use those eventually, but I’m still getting intermittent results with my hand sharpening skills.
I started to list all my 1/2" stuff on eBay and buy all new 3/8" but I stopped as that might be foolish too?
Any suggestions or words of advice?

http://i228.photobucket.com/albums/ee288/earlysb1/Boxford%20CUD/cud15.jpg

Optics Curmudgeon
01-01-2013, 03:24 PM
4-way posts like that are used with shims under the tool to get on center. Yes, it's annoying, hence the popularity of quick change toolposts.

Pherdie
01-01-2013, 03:29 PM
First off, I'd hang on to the 1/2" tooling, you'll get nothing for it going through E-Bay. Then I'd use 3/8 with the current tool post. Both statements are predicated on the assumption you'll eventually find an AXA tool post a valuable addition to your tooling and will find a use for all your tooling, in addition of things to come.

tylernt
01-01-2013, 03:34 PM
Do you have a benchtop sander of some kind? You could sand those oversize holders down. Doing it by hand, you won't get a perfect result, but a slight error can probably be ignored and if you go too far you can shim it back up.

Gary Paine
01-01-2013, 03:37 PM
A couple thoughts come to mind. With a torch and a bucket of wood ash to slowly cool down in, the insert holders could be annealed for machining. In my shop, I wouldn't reharden because they wouldn't get so much wear.

If it isn't hardened, the post itself could be milled out with a wider slot on one side for the holder.

In either instance, I'd spend plenty of time making measurements first so the insert would end up exactly on centerline when you're done and you will not have to mess with shims.

donf
01-01-2013, 03:41 PM
4-way posts like that are used with shims under the tool to get on center. Yes, it's annoying, hence the popularity of quick change toolposts.

Thank you for the reply. Yes I really don't mind shimming, it takes maybe 30 seconds at the most. Every thing else takes so much longer. So what you were saying is go with a import quick change and ditch the English made Boxford post? I see on eBay some of the better 4 way posts used sell for more than the cheapo AXA imports - so are people buying them for collections or do they have advantages that I might not want to loose. I don't have anything to compare it to other than the post on my imported lathe or even worse the post on my 6" atlas. So far its a tank build wise, and If I can get the right height it will work ok for me.

Thank you all for the replies I will read though and follow the tips.

tylernt
01-01-2013, 04:11 PM
So what you were saying is go with a import quick change and ditch the English made Boxford post? ... or do they have advantages that I might not want to loose. If you don't mind shimming, and don't mind losing zero on your cross-slide (or compound) when changing tools, a 4-way is just as good as a quick-change -- if you only need to change between 4 tools.

However, as soon as you throw a 5th tool into the mix you're going to want another 4-way turret to swap in and out. Even so, when you look at per-tool costs, as long as a turret is 1/4th the price of a quick-change holder, turrets end up cheaper.

Disclaimer: I use and like my 4-way just fine, so I may be biased...

Boostinjdm
01-01-2013, 05:41 PM
This is the wedge type. Find a discount code and get one. You'll thank me later.
http://www.use-enco.com/CGI/INSRIT?PMAKA=890-9636

becksmachine
01-01-2013, 06:02 PM
It might be worth the $15 to try a stub length 3/8" carbide end mill?

.020" depth of cut with fine feed would let you know real quick if you have any chance.

Dave

I couldn't tell from the OP whether the end mill already tried was carbide?

PixMan
01-01-2013, 06:35 PM
I'd ne happy to help you out with the toolholder issue. I've got a lot of experience milling or surface grinding toolholders down to a usable size.

Where are you located? Your location showing "USA" doesn't tell much.

donf
01-01-2013, 06:41 PM
Thank you for all the tips! :)
No, the end mill I tried was a M2AL. Its some type of import end mill that was only a few dollars more than the HSS end mill from Shars or Enco. I think I will buy a few nicer end mills just in case I run into something hard again even if I don't use it to cut the insert holders down.

Enco does have a good deal on the Phase II post. I did some more reading and the imported axa tool posts seem to be finding homes on a lot of nice machines here with no bad feed back.

donf
01-01-2013, 06:42 PM
I'd ne happy to help you out with the toolholder issue. I've got a lot of experience milling or surface grinding toolholders down to a usable size.

Where are you located? Your location showing "USA" doesn't tell much.

Medford Oregon is where home is. :)

BigJohnT
01-01-2013, 06:49 PM
To cut hardened steel with a carbide you need to take a cut big enough to pull the heat out with the chip. You need HP and rigidity to cut hard stuff, a skim cut will just dull your endmill due to the friction.

Your location is a bit hard to tell if your a neighbor or not to say the least...

John

donf
01-01-2013, 07:02 PM
To cut hardened steel with a carbide you need to take a cut big enough to pull the heat out with the chip. You need HP and rigidity to cut hard stuff, a skim cut will just dull your endmill due to the friction.

Your location is a bit hard to tell if your a neighbor or not to say the least...

John

Ok I changed my location. With the little X3 Seig mill I think I might be out matched then even with a carbide endmill. I thought is was a pretty sturdy mill until yesterday. It was moving all around even with a light cut attempt and I have it bolted to a steel bench. I may try to anneal the insert holders one at a time and see how they cut with a new endmill. I really don't care too much about them if something goes wrong. They were under $30 from Shars and did a great job for the money over the past few years.

Thank you for the replies!

BigJohnT
01-01-2013, 07:10 PM
Ok I changed my location. With the little X3 Seig mill I think I might be out matched then even with a carbide endmill. I thought is was a pretty sturdy mill until yesterday. It was moving all around even with a light cut attempt and I have it bolted to a steel bench. I may try to anneal the insert holders one at a time and see how they cut with a new endmill. I really don't care too much about them if something goes wrong. They were under $30 from Shars and did a great job for the money over the past few years.

Thank you for the replies!

Yea, your a bit far to drop by and cut them down here. If you can't throw a "rooster tail" of chips I'd say your out matched. The key after a cut is the material your cutting is room temperature, if that is the case then your pulling the heat of cutting out with the chip. Instead of a fly cutter try a smaller endmill.

John

J Tiers
01-01-2013, 07:56 PM
Don't modify the insert tooling. (it IS insert stuff, right?)

Get a QC post, if you want, OR make a proper toolpost. or maybe fix your shims....

I hate wobbly compressible stacks of shims.... My toolpost has a slot for EACH SIZE of tool. 1/4, 5/16, 3/8, and 1/2.

The slots are cut so that the proper size tool ends up with top on-center. That way there is no shimming, unless the cutter is one I just HAVE to use, and it has an edge below center.... I don't mess with that much, don't have to.

This whole thing about "losing position" has never yet been an issue for me. I keep thinking I ought to get a QC post, and then it ends up as no particular issue, so I don't..... I'd be solving a problem that everyone says I "just must be suffering from", but I don't seem to be. But I don't run the sort of production that requires swapping tools all the time if I can help it. I don't particularly like running production of any sort, I like variety.

I have a considerable amount of cutters, picked up over time in all sizes and shapes, so I can set up 3 or 4 positions with what I want, in whatever size fits the slots.

A decent post will take a chunk of steel and some time to mark it out and mill slots, drill holes and tap.... Then you can get rid of the box of shims, and cut a short but annoying step from your setup.

An alternative, which you may have already done, is to mill some fixed shims of thicknesses which fit the tools you have and which put them on center. Then it isn't 30 sec, its 3 sec to grab the right size and stick it in. You only need 2 or 3 of each size, keep them in the drawer with the cutters of that size.

You would cut at least one side of the existing post to accept the 1/2" shanks.

.

donf
01-01-2013, 08:03 PM
Thank you for the help. I learned a bit about using my mill from your posts. I think I'm almost at the point of buying an import AXA post. I think people are relativity happy with them as I couldn't find much bad at all as long as I order the wedge style. I really didn't see the need yet, but if more experienced people say I will end up there anyway, I might as well do it now and not over work the little mill. I do have one AXA holder already that came with some other parts off the internet and confirmed that the height is just under center line with the 1/2" carbide bit.

donf
01-01-2013, 08:13 PM
Don't modify the insert tooling. (it IS insert stuff, right?)

Get a QC post, if you want, OR make a proper toolpost. or maybe fix your shims....

I hate wobbly compressible stacks of shims.... My toolpost has a slot for EACH SIZE of tool. 1/4, 5/16, 3/8, and 1/2.

The slots are cut so that the proper size tool ends up with top on-center. That way there is no shimming, unless the cutter is one I just HAVE to use, and it has an edge below center.... I don't mess with that much, don't have to.

This whole thing about "losing position" has never yet been an issue for me. I keep thinking I ought to get a QC post, and then it ends up as no particular issue, so I don't..... I'd be solving a problem that everyone says I "just must be suffering from", but I don't seem to be. But I don't run the sort of production that requires swapping tools all the time if I can help it. I don't particularly like running production of any sort, I like variety.

I have a considerable amount of cutters, picked up over time in all sizes and shapes, so I can set up 3 or 4 positions with what I want, in whatever size fits the slots.

A decent post will take a chunk of steel and some time to mark it out and mill slots, drill holes and tap.... Then you can get rid of the box of shims, and cut a short but annoying step from your setup.

An alternative, which you may have already done, is to mill some fixed shims of thicknesses which fit the tools you have and which put them on center. Then it isn't 30 sec, its 3 sec to grab the right size and stick it in. You only need 2 or 3 of each size, keep them in the drawer with the cutters of that size.

You would cut at least one side of the existing post to accept the 1/2" shanks.

.

Yes the tooling that I was trying to cut down is insert tooling. I really don't care about that either, but a year ago I had the "great idea" to buy a lot of name brand inserts thinking I would always have the tool holders. That's where the dollars add up a bit. I bought a set of shims off someone and made some, so yes it doesn't take long at all to get the right height.

tylernt
01-01-2013, 09:20 PM
This whole thing about "losing position" has never yet been an issue for me. I keep thinking I ought to get a QC post, and then it ends up as no particular issue, so I don't..... I'd be solving a problem that everyone says I "just must be suffering from", but I don't seem to be.I haven't had a problem either, but since I'm a newbie I wouldn't know better anyway. Apparently though, it's not a big deal.

J Tiers
01-01-2013, 10:08 PM
I haven't had a problem either, but since I'm a newbie I wouldn't know better anyway. Apparently though, it's not a big deal.

It can be if you run a lot of the same part, and need to swap cutters for different portions of the part, but cannot afford to "un-chuck" the part until it is completed, due to losing center.

if you CAN un-chuck, you may be able to run each operation on every part one after the other, and move to the next cut and tool before running all again with that cutter. That usually takes longer and loses precision. But it is do-able, and better than re-setting up for each individual part and cut.

I don't do that sort of production, so I flat don't care. Plus I have a turret setup, which can fix some of those issues (not all).

danlb
01-01-2013, 10:33 PM
The biggest advantage to the QCTP is that it is quick change. If you have enough tool holders you tend to use the right tool for the right job instead of using whatever tool is mounted. When I had a turret I would often use the tool with the 90 degree edge for normal turning because it was a hassle to swap to a proper roughing tool. I have more than 10 tools in QC holders, so I swap the right tool for the right job now. It takes 5 seconds.


Dan

rohart
01-01-2013, 10:38 PM
This shimming - every tool you use should be stored with the shims that will bring it to centre,

I use a QC Dickson post, and I don't have enough holders. I have a few holders with my 'goto' tools, and they stay in the holders. Then I have two holders for varied tools. They are both set to an identical height, and every tool in the drawer has its own shims. I need to reshim every time a tool gets more than a touch up, of course, but to shim a tool each time would be laborious. I even kept tools with their shims when I ran a lathe with no space for any holder.

Its a matter of half a minute to whip a tool and its shims out of the holder, into the drawer, another one out, screw down and go.

Carld
01-01-2013, 11:41 PM
donf, buy a QC tool post, it will be the best tool you ever buy for your lathe. Put the four way tool post in a box and store it somewhere. You'll probably forget where it is and never use it again. I used them at work for years and put up with a four way at home until I retired and started doing more work at home. It didn't take long before I wished I had replaced it when I bought the lathe and I started adding tool holders for it.

donf
01-02-2013, 12:30 AM
Thank you all for the input. I spent the afternoon reading and trying to figure it all out. I am having another member (PixMan) cut down the insert holders for now and that will get me a lot of usable bits with the tool post I have now. The holders I'm having cut are not that nice of a set, it only cost me $30 or so about five years ago from Shars, so I don't mind altering it to get me going for now. I will start looking to pick up a quality used QCTP pieces as they show up on eBay or Craigslist and budget allows.

PeteM
01-02-2013, 01:36 AM
I'm not sure what the center height of your lathe is, but from the looks of your 4-way post you will find that AXA toolholders (if they bottom on your compound) will also put a 1/2" tool above center height.

There are two fixes for this. One is to hang to the holder over the edge of your compound (less rigid, not always possible in, say, threading with the compound at 29.5 degrees. The other is to buy import AXA size holders and cut the opening just a bit wider.

donf
01-03-2013, 02:52 PM
I'm not sure what the center height of your lathe is, but from the looks of your 4-way post you will find that AXA toolholders (if they bottom on your compound) will also put a 1/2" tool above center height.

There are two fixes for this. One is to hang to the holder over the edge of your compound (less rigid, not always possible in, say, threading with the compound at 29.5 degrees. The other is to buy import AXA size holders and cut the opening just a bit wider.

I was trying to figure out the exact height to have the 1/2" insert holders machined too and then I found another problem. The length is too long to put more than two in the post anyway. The four way post really seems designed for short stubby 3/8 HSS bits, but if it was, I don't know why the tall gaps in the post. After messing with it I'm giving up on modifying any of my 1/2" carbide tooling with the original post and will just have to get better at hand grinding HSS until I get an QCTP.

The lathe is a 3656 5" (10") Boxford. I have been able to substitute a few parts from a South Bend 10". I have one China AXA holder that came with some other parts. It looks to me that with this one at least, a 1/2" bit will be just a hair under the lathe center line. I think I will just order a import AXA TP and go from there. If something has to be modified then I will do so. The other post I was considering was the Omni Post, but I have emailed the company with questions with no response, so that's not a good sign.

http://i228.photobucket.com/albums/ee288/earlysb1/Boxford%20CUD/IMG_00941.jpg

Carld
01-03-2013, 04:01 PM
Most the time you can only get two tools in a four way and not have them interfere with each other or the work or lathe. Occasionally I could set up three tools that didn't interfere with anything especially if you didn't have to move the cutter off perpendicular to the work axis.

tylernt
01-03-2013, 04:51 PM
Most the time you can only get two tools in a four way and not have them interfere with each other or the work or lathe. Yeah, for a turret to really work well you need at least two or three of them. I use one turret for rough facing, rough turning, finishing, and threading, and a second for parting and boring. Plus I keep a third around for odd jobs so I don't have to disturb any of my regular tools.

I got HSS facing and a turning tools plus two other tools in the same turret by putting them in crooked and changing the grind to compensate. You can see how they are arranged in this video: http://www.youtube.com/watch?v=h0qZpucVYo8

donf
01-03-2013, 06:30 PM
I ordered a Phase II wedge AXA kit from Enco with the discount code and will be putting the 4 way post away. This was turning into a hassle that I didn't want to mess with. Thank you for all the feed back and advise. Especially to PixMan who was going to try and mill down the insert holders for me, but now hopefully it will work without that. :)

Boostinjdm
01-03-2013, 07:34 PM
What code did you use? I just made an order, but I forgot a few things.

donf
01-03-2013, 07:55 PM
What code did you use? I just made an order, but I forgot a few things.
I think it was DECWEB only good for 15% off $150+ It expires in a few days
PRSDEC was another code I found but I didnt use it as it was free shipping and couldn't be combined.

donf
01-04-2013, 10:11 PM
Done! All the 1/2 stuff works fine now. :)
http://i228.photobucket.com/albums/ee288/earlysb1/Boxford%20CUD/cudpII.jpg