Lathe tool post question

On my recently acquired Reed & Prentice lathe is an old style tool holder (lamp post style??) which really sucks.

But the alternative, get a modern stable setup, is a bewildering task. There are many styles and a large swing in prices. My lathe is a 12" and I could spend anywhere from about $100+ (Enco, piston style) to a small fortune for a KDK holder and what I really need to get is an education in the differences.

Can anybody here help me with this??

Regards Uwe

PS. I do not do production work, rather slow poke experimental tasks.

Reply to
Jaggy Taggy
Loading thread data ...

The cheaper piston type is like a CD compared to a perfect 33rpm LP. It will be a huge leap from your AM radio.

Reply to
Tom Gardner

You'll probably be happy with the cheaper Enco kit, which goes on sale at a substantial savings periodically.

Reply to
ATP*

Another alternative: Learn to use the lantern style toolpost (in other words, learn to grind tools for it). I have an old Logan which came with (most of) a lantern post as well as a newer style tool holder. I got the missing pieces and find that I use the lantern post almost exclusively. The reason I prefer it is that I have much better control over the cut. The newer style posts are, of course, superior if you want to run tools with replacable carbide inserts. But the problem with them is that the cutting forces tend to be a lot higher and the older machines tend not to have the power or rigidity to get good results. I find that the only time I use carbide is for cutting stainless, but I don't do that very often. I run mostly aluminum and a carefully shaped tool in the highly adjustable lantern post gives beautiful results with a minimum of profanity. Of course, you have to have a good tool grinder. Mine is a cheapie, but I made a good tool rest (normally set 7 degrees off from the centerline of the wheel) bought a good "fine" wheel for it and keep the wheel dressed square. I'm the first to admit I have a lot to learn about the art of grinding tools, but I find I can make one that does what I want without a whole lot of effort.

Reply to
Jerry Foster

1) carbide tools can be run in a lantern toolpost - the type with the carbide tip brazed to the steel shank. 2) HSS can of course be run in a QC type as well. 3) the best way to use a lantern toolpost is to remove and discard the 'tool holder' - the forged steel item that is typically used with its shank in the lantern toolpost, and the HSS blank held in the end with a square setscrew. Instead, use the largest tool which will fit in the slot of the toolpost, right in the post without any holder. It will need to be shimmed up to the correct height but this can be done with other tool bits or with simiar-sized bits of steel.

The increase in rigidity and the reduction in tool overhang makes a *big* difference.

Jim

Reply to
jim rozen

I ordered the quick change tool post from HF and was pleasantly surprised to find a nicely finished, precision tool, made in China. It has made a new machine out of my ancient 10" Atlas. The old rocker style toolholder was a real PITA. It also comes with a boring bar holder and cutoff tool holder. This all for under $100! Bugs

Reply to
Bugs

I agree Phase II AXA size would work fine. $89.95 Look back a few days and get the Free Shipping! code. Keep the lantern style for the odd project that requires it. After 18 months with the Phase II I have yet to need the laneter style for anything. BTW I've used the QC toolpost for a milling attachment on several projects. Works OK in a pinch.

Reply to
Rex B

Reply to
F. George McDuffee

I've had good luck with the wedge type Phase-II toolpost. The wedge posts are a bit more expensive than the piston type, and a bit more rigid, all else being equal. Phase-II makes both types. The toolholders are the same for either type. That said, many are happy with the piston posts for occasional or lighter work.

For a 12" lathe you'd likely want the '200' series (aka; "BX' series) size.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

You make the complete toolpost? That serrated base looks like a non-novice undertaking.

I recently made a block-style toolpost for a 10" Atlas. Design was loosely based > see

formatting link
Cheap to buy and easy to make using standard tooling [no

Reply to
Rex B

May be true. The 12" is right on the line. Depending on space between top of compound and CL of spindle, either may work. Should be a simple measurement of existing AXA and BXA toolposts: lowest toolbit height with largest (1/2" or 5/8") bit, and highest height with smallest (1/4"?) bit. CL needs to be within that range. Right?

Reply to
Rex B

Sounds about right. The 12" should work with either the AXA or BXA series. I suggested the BXA size on the theory that the largest that will fit will give the best performance. Cost is little different. The key factor is the tool height relative to the lathe axis height.

At home I have a Logan 10", and use the AXA series. I wouldn't want any larger for THIS lathe, but the AXA works well, and is a big improvement over the lantern style post. For larger tool bits I cut down some of the toolholders (lowered the slot). It weakens the holder a bit, but I've not found that to be a problem, they still work well.

At work I have a 14" Rockwell, and use the BXA size post. It MIGHT work with one size larger, but the BXA meets all my needs on that size lathe.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

The other consideration might be that you have a bigger hunk of steel between you and the work. Might be access/visibility issues on some jobs. I guess that's when you dig that lantern post outa the back of the drawer.

Reply to
Rex B

good point.

We found the major PITA for machining is not angular positioning but tool height. We don't normally use the base at all. We have Emco lathes with a stud in the compound rather than a t slot. We did however make up a base using a rectangular plate 3/16 thick with a spot drilled holes at the right radius. These were located using careful layout and a pin type locator. We get good angular repeatability.

We just purchased a rotary table as part of our gear making project [see thread on this about xmas time] and will try making a serrated base.

Some of our students want to be gunsmiths and are interested in fabricating a "armstong" slotter that they can use for cutting the space for the extractor when rebarreling rifles. I have located some pictures and plans for two english units. Anyone made one of these? Any comments or suggestions?

GmcD

Reply to
F. George McDuffee

As a follow-up to several emails that may be of interest ...

The KRF tool holders work very well for us. The plans are very helpful, but are "perfection." Very useful tool holders can be made from 1 X 2 hot rolled with a minimum of machining. It is helpful to make up a few "blanks."

One custom item we made that is popular with the students is a tool block that mounts a 5/8 jacobs type chuck using 1/2 X 20 setscrew into both the chuck and the block. This allows power feed drilling/reaming. The centerline of the drill chuck and the tool post should be in line to avoid any tendency to twist. [We made two ...]

The 1_1/8 diameter tool post works well with no flexing or chatter for us. 1_1/8 is as large a diameter at the standard 5C collets will take. Water hardening drill rod from Enco seems to be the best choice for the tool post.

The tool post hole can be bored on a lathe using a faceplate or 4 jaw, but a sharp 1_1/8 Silver and Demming drill is close enough.

The shanks of most tools such knurling tools, parting tools and and carbide holders are soft [enough] that you can drill mounting holes to allow these to be attached to a KRF style blank. Two

1/4 X 20 cap screws (with blue locktite) seem adequate. Again not perfection, but very useful tooling at minimal cost as this allows the utilization of donated large shank industrial tooling and large carbide inserts. Negative rake carbide tooling will work but power and speed are marginal with our lathes.

If you stick with the screw sizes shown on the prints, a single "Smitty" hex key set will work for all the screws. If you use a larger clamp screw [3/8 in place of 5/16] you will need two seperate "Smitty's"

Reply to
F. George McDuffee

There's actually not a lot of difference between the AXA and BXA sizes. Every little bit of added rigidity is useful, however, so use the largest size that will fit your late. The limiting factor is center height, as we've been discussing. And, yes, there are times when the old lantern post is still useful. I also find a bunch of the European style block toolposts useful for larger sized and odd tool bits.

Dan Mitchell ============

Dan Mitchell ============

Reply to
Daniel A. Mitchell

Good information. Next one will incorporate some of these suggestions.

Reply to
Rex B

[ ... ]

[ ... ]

I agree with both choices -- as they match the ones which I made for my 12x24" Clausing -- 200 series Phase-II (same as BXA size for Aloris and some other brands, whose tool holders you can also use with the Phase-II toolpost).

My considerations were:

1) The AXA/Series 200 size was at its maximum range on a 12" lathe so I figured that the next size up would be under less stress on heavy cuts. 2) The Design of the wedge style pulls the holder against the flats on either side of the dovetail, producing a more rigid lock-up than the piston style, which pushes the holder *away* from the body of the toolpost, producing lock-up only on the angled sides of the dovetail, allowing for a bit more flex.

I later discovered another reason for preferring the wedge style. That is that the angle through which the locking lever swings on a wedge style is limited, while it shifts about 90 degrees towards the chuck when you shift from the turning (side) dovetail to the boring/facing dovetail (side towards the length of the workpiece). And when there is no tool holder on the toolpost, it is free to turn a full

360 degrees, which can bring the handle into contact with the spinning chuck. At least one poster here in the past encountered this very phenomenon, resulting in the plastic ball grip on the end of the locking lever turning into shrapnel when hit by the chuck's jaws.

Note that once you have used the quick-change toolpost, you will not want to go back to the lantern style for most things -- nor will you want to go to a turret toolpost. The reason for this is that each tool gets its own toolholder, which has an adjustment nut which can be locked in position so every time you drop the tool holder onto the toolpost and lock it, it will be at the same height. Even when you are not in a hurry, you may be reluctant to change tools to a more appropriate one if you have to stop the spindle and re-adjust the height of the tool. (The same reasoning applies to a quick-change gearbox for threading and turning when contrasted to a change gears style, where you must get your hands rather messy changing the gear train to get the proper feed rate. (You *will* have to change to get the proper pitch for cutting threads, which may make you postpone learning to cut threads.)

With a lantern style, you have to tweak the height of the cutting edge each time you replace it.

With a turret style toolpost, you have to place a stack of shims under the tool's shank to bring the edge up to the proper height. This is not too bad for a production run, where you load the turret with the tools you need for that project, and rotate to bring up the next one as you finish one part of the task. There, the time for the setup to height can be swallowed in time saved in the actual production -- even over a quick-change toolpost. But for the kind of work which you suggest you will be doing, the quick-change toolpost will make life easier and your time in the shop more productive, and thus probably more satisfying.

The other style which you mentioned, the KDK -- if it is the one which I am thinking of -- is *very* nice, but *very* expensive, especially in this country. It allows you to drop on the tools at 15 degree increments, so if you like to cut with angled tools, this would be the one for you. But the price may discourage you from getting enough of the tool holders to cover all of your tools, so you lose time swapping tools in tool holders and having to re-adjust the height.

This is where the Aloris/Phase-II style really wins. There are lots of makers of the tool holders, and they interchange between the different brands (except in some cases with piston-style posts, where the depth of the dovetail is too great, since the piston *has* to press on the bottom of the dovetail, so the depth of the dovetail is more critical. With the wedge style, the dovetail on the toolpost increases in width to lock the holder to the post.

I hope that this helps, DoN.

Reply to
DoN. Nichols

Jerry thanks for your note. While in the end I will probably buy a modern type tool post you pointed out a few things that I had not thought of, namely that this old Reed & Prentice might not be tight enough by design to make heavier cut. I also should keep in mind the importance of a correctly shaped and sharp bit. Here it would be interesting to see what you consider a 'good' tool grinder?

And after all I might look at that old lamppost tool holder and try to find the verastility you mention.

regards Uwe

Reply to
Uwe

Yes, this was actually the main reason for me to consider an alternative to the lamppost style. As I said I do not do production work and I am not a trained machinist, I sometimes 'design as I cut' and along with that goes a fair amount of changing bits, a real pain with the old style holders and a source a great possible error.

Uwe

Reply to
Uwe

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.