[ninefinger]

Well I am at the point that I thought I would send you all a link to my files. Currently, they are just a conversion of the original .SAT file to SolidWorks2011. I plan on continuing to improve the design, and make 2d drawings of the parts as well. Both the original files and my SolidWorks models are available at my website.
Automatic Lathe Tool Changer

Josh,

Is there any way you can down convert the files to SolidWorks2008 compatibility? (or Pro/e WF4 - its what I usually use)

Thanks,
Mike

[jeremy0203]

You can put any tool you want because you use a custom tool bracket. There are bolt holes on the from face and the outside of the tool changer. So you make this tool bracket to hold the tool however you want. Then bolt it to the tool changer.

This video has several tools on it.Scratch built CNC Slantbed Lathe - RUNNING! - YouTube

i love that guys lathe, i would so love to make me one of those

[jupdyke]

Mike: I saved the files as ProE format and added them to the website. Let me know how they look when you open them because I have never really gone from SW to ProE. Usually it is the other way around. Unfortunately you wont have the feature data. I know that SW has a feature recognition tool, maybe the new ProE does too.

For anyone else I am happy to convert my files to whatever you would like. Just give me a shout.

Jeremy: The lathe in that video is what inspired me to start this project. I figured I would build the tool changer first because it wouldn't cost too much to get started. Also, it makes a nice addition to my 3D modeling portfolio, I am planning on making some animations soon.

I added a photo-rendering of the tool changer to my website. If you check it out, click on the picture to see the large version and tell me what you think. SW amazes me sometimes.

Josh

[ratindahat]

After seeing his holders it makes more sense.

[ninefinger]

Thanks Josh - I'll check them out when I get home tonight.

Mike

[Sparky_NY]

One quick question. Is there a reason that we can't extend the grooves or shorten the teeth on the locking rings? The reason i ask is that it seems we have the potential to induce some radial movement in the locked position as it stands. if the teeth are too long then the angled sides will not lock together which would leave some play.

if the teeth are shortened(or grooves lengthened) slightly, we will lock on the angled walls which should keep the parts from having any radial play. Does that make sense? Am i overlooking something here?

your not overlooking anything there should be a slight gap between the teeth at the bottom flat when locked up, that way the angled sides locate everything exactly and lock up tight.

[ninefinger]

Hi Josh,

There are a few missing facets on the tool holder when converted to pro/e. Perhaps IGES or some other file interchange format?

Looking good though and I appreciate your efforts and willingness to share.

Mike

[jupdyke]

Mike,

Can you tell me which facets are missing? Maybe when I converted the files. Many of them I remodeled and I know that I didn't put in all the fillets around the edges, because I was lazy. Maybe my original files are the issue. It seemed like quite a few people were interested in them so I figured I would release what I had. I still want to turn it into some 2d dimensioned drawings as a pdf. And maybe make an animation of it being assembled to add to my portfolio.

Josh

[ninefinger]

Josh,

Well, it appears that there is some of the main body structure that is missing also. I've made a 3d pdf of the converted toolholder in Pro/e - have a look and you'll see what I'm seeing. A standard pdf of the assembly shows that the main housing did not show up (its in the list of parts but nothing there..) - sorry a 3d pdf of the assembly was too large to attach..

Mike

Edit: the 3d pdf of the tool holder didn't attach either - 2d will have to do..

[jupdyke]

Mike,

Thanks for letting me know. I wonder if the main housing is just not included in the assembly. I uploaded a v2 of the ProE which I re-saved the housing and tool holder separately, instead of as a batch with all the other files. I also uploaded an IGES file of these two parts. I am not eager to make IGES of all the parts because I can not batch process it easily. I will do it if someone needs it. But unless someone does, I am not going to waste my time.

Also, I am working on a new housing made from bar stock aluminum. 3/8" thick, 4" wide. The sections will be cut and bolted together to form the housing. This drops the price for the main housing be over half in raw materials. If I can get access to a decent tig welder I will weld the parts together instead of bolting. I am not overly fond of mixing inch and metric. But getting metric bar stock is much more expensive in the US and I don't want to convert the whole damn thing. /sigh I have not found an happy solution just yet.

Anyway, let me know how those files work for you. And attached is a picture because everyone loves pictures.

Josh

[Sparky_NY]

Did this project die? It was interesting at a time when I am very close to building my tool turret.

[jupdyke]

Sparky_NY,

I am still around and I just checked that my site was still working. I had a little trouble with it for a short time. I am still planning on building this turret for my new lathe. However, time and money are my enemy right now. I just moved and am looking for a job. Hopefully I can get back working, which will give me the money to purchase parts for this project.

I also will have to find an mill I can use to make the parts, since I no longer have access to the old shop.

I am still around and I am sure other people are as well.

josh

[ratindahat]

Ok, so one more potentially stupid question from me.

When the tool holder rotates, is it just the spring force tying everything together? In other words, is the gear held to the shaft through spring tension alone?

[jupdyke]

Ratindahat,

I am not positive what you are asking and I think part of the problem is that many of the parts don't have clear names. The motor turns the shaft through a timing belt pulley which is connected to the shaft with a keyway. The shaft can slide forward and back freely and rotate at any point along the travel.

On the front of the tool changer there are two interlocking parts (sometimes called hirth coupler or locking rings). These help to realign the tool holder into one of 8 set positions. This means you can reposition the tools very accurately without needing the rotary motion to be very accurate. Another way to put it is: Even with some misalignment on the rotary motion the interlocking parts will correctly position the tool.

The motion forward and backward is accomplished by a pneumatic cylinder on the back of the tool holder. This cylinder pushes the shaft forward to disengage the locking rings and allow it to rotate. Internal springs push it back when the cylinder is retracted. This is nice because it means that the shaft and the cylinder are not actually connected, but rather push on a ball bearing to reduce friction and wear.

Because the forces on the tool should be pushing the tool into the machine or trying to rotate it the interlocking parts take all the load. The only limitation would be if you were trying to pull the tool away from the work piece (not a common lathe operation). Because the taper on the interlocking ring is steep it would take a lot of rotary force to pull the rings apart.

another option that some people have though about was to use the air cylinder to push and pull the shaft. It would be possible to get more force holding the interlocking rings together. But has other trade-offs such as complexity and requiring air pressure the entire time you are holding the tool in place.

I hope that helped answer any questions.

josh

[ratindahat]

you answered it. The main functionality i understand. I just didn't see a keyway, keyslot, or key in the model. It was the shaft/pulley connection i was asking about.

I've been working on my own version of this thing that is a little larger and has integrated holders for 3/4" tools on the face. If i ever finish it i will post up some models.

thanks for the response. I assumed a key, but assumptions aren't always a good thing to make.

[mofome]

If I can share my opinion I have looked at many turret designs and simplified it but this is a nice design just seems hard for the little guy to make I work with many engineers and I am a 20+ year machinist but at the end of the day simpler is better I can post a pic if I can figure out how it will look similar but simpler to build I think

[MRM RCModels]

Great thread. Got to make one

[jupdyke]

Hello again everyone. I finally got access to a good shop and they even have a cnc mill with a rotary table. I have been getting trained on the cnc and am working on some other projects to cut my teeth on. They also have a tig welder set to weld aluminum as well as a bunch of other things that will make life much easier. I really would like to make some or all of this project, but I don't have a lathe to put it on yet. Gotta finish up some other projects first. But if anyone was interested in working together to make one of these I would be happy to do some machining for you. If we can get a few people interested then I can set up the cnc mill and cut out several sets at once. We could even spring to have parts hardened, anodized and otherwise made more awesome. I am happy to do the machining, if people pay for the bits and stock material. I was thinking we could all chip in and build 4 or 5. In exchange for the machining time I would end up getting my stock paid for. Anyone interested?

Josh

[jupdyke]

Hello All,

I would like to start making some parts for this turret. The first parts I would like to make are the sprockets / hearth couplers. They are made of 4140 steel and hardened. I have access to a way to heat treat them and I think it will be free since they are so small. So if anyone is interested in building one of these and would be willing to pay for the material I will gladly machine a pair of the sprockets for you. Below is what I would need to do it. PM me if you are interested.

Raw round stock 4140 steel, 3" diameter at least 1.5" long. Mcmaster part number 8960K53
15 degree taper end mill Mcmaster part number 8936A95
We will also need to make a fixture to hold it. Here is a link to an easy way to fixture it.
http://www.ebay.com/itm/6-X-2-X-1-25...item45eda73e16

Let me know what you think,
Josh

[Kobi see]

Hey Josh, does your offer to machine a pair of the sprockets still stand?