SB Lathe

[johnm]

Folks -

I am having trouble visualising how a lathe is set up in conjunction with SB. Could somebody point me to, or post a picture? I am interested in the finding out more about this setup...

Thanks!

John
Lakeport, CA

[paco]

Hi John,

have you had a look at thoses documents:
1) (http://www.shopbottools.com/files/SBD139_000824Indexer.pdf)
2) (http://www.shopbottools.com/files/indexer.zip)

from this section. (http://www.shopbottools.com/manuals.htm%20)

[gerald_d]

John, what you are calling a lathe, is called an indexer by these folk.

Folks (as John likes to say
) -
I think that John wants to see pictures of indexers mounted under your tables' gantries.

[hespj]

John

Here are a couple of photos of my indexer. It consists of a headstock, tailstock and a couple of bits of ali track each about 2' long.


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I've mounted it by routing a shallow groove in the spoilboard with bolt holes which allow the head and tail stocks to be spaced as far apart as the length of the table. I have a 12" Z on my SB so am able to do this. It might not work well with the standard 6" Z, because the indexer itself is about 6" high. An alternative is to mount the indexer on the X rail of the SB - on its side rather than upright.

It's about 5" from my spoilboard to the indexer axis - 4" from ali track to axis.

I havn't been able to do anything with my indexer yet, apart from a few hours messing about, as I'm to busy with other things; so I'm not really able to comment on how useful/cost effective it is.

There seems to be several ways of actually using the indexer, from machining one side of an object, flipping it 180degrees and machining the other side; to "wrapping" a "flat" X-Y SB file aound a cylinder (Y becomes the 4th axis), to true 4th axis CAM software.

[jhicks]

I have always been fascinated by the indexer idea but know very little about it. I have a Legacy Ornamental mill and keep thinking that there must be a way to adapt it to the bot but haven't received much encouragement on that idea. Is there anyone near Chicago using an indexer that would like to share their experiences with it? Photo attached of some stair cases we worked on with the Legacy which I would love to be able to duplicate or market with the Shopbot consistency, repeatablility, and automation vs the one at a time hand tuning and turning of the Legacy.
If yes, please e-mail me at jhicks000@ameritech.net (mailto:jhicks000@ameritech.net).
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[waynelocke]

Jerry,
I used to have a Legacy. It was a good machine but I now use my Shopbot. I ended up selling the Legacy and my PR machine and almost paying for a new 5'X8' PRT with the indexer. I had the table fabricated so that I have 4'X8'over the table and the indexer is always set up. I purchased only the stepper motor and mount from Shopbot and used a Harbor Freight lathe with a fabricated extension. Here are some pics.
Wayne

[waynelocke]

Picture laoding problems.
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[jhicks]

Thanks, I have thought about swapping out the legacy as well for the indexer. How difficult was the conversion to go to software driven wrap around files?

[paco]

Nice setup Wayne!

Do you have any flex from this table built?

[dmdraper]

John H.,

Would you mind supplying a source list for the various pieces/parts you used?

Thanks,

Dave

[hespj]

Me? I just bought it from ShopBot - http://www.shopbottools.com/indexer.htm

John H

[waynelocke]

Jerry,
I started using Vector to make the toolpaths for doing spirals and columns but the indexer files that come with the Shopbot are sufficent. I don't have any experience wrapping graphics or similar files to the columns.

Paco,
I haven't noticed any flex in the table but it is pretty well braced and is all welded construction.

David,
I assume your question was to me.I use a Harbor Freight lathe which I think I paid about $170 for. I mounted it so that I could slide the stepper onto the outboard side of the headstock and use it as a regular indexer. I can also slide the stepper back and run the lathe, primarily for sanding. I mounted a simple toggle switch with a plywood trigger on the stepper to prevent being able to turn the lathe on with the stepper motor attached. I use the legacy chucks for mounting the work.

I don't use it a lot but it comes in very handy for a lot of things.

Wayne

[paco]

Hey Wayne!

Seem your lathe/indexer setup saved you some dollar right?! I think I like it... yes I do!

How does your stepper is connected/coupling with the lathe? What are the modifications involved?

Thanks for sharing the pics!
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I think welded table are stiffer... combined with some bracing; one can get a quite rigid frame. When I lift one corner of my table (which is also welded) it does'nt distord and tree legs lift thogeter!

[alabama_davo]

I have a new indexer in a box for sale. I built the table before I bought it and I like my table so much I think I'll just sell it..
please call it anybody is interested

Dave Patterson
205-222-6866

[johnm]

Wayne -

Thank you SO much for emailing pics of your indexer and the table plans! I think we are going to be able to place our order for a 'Bot next week!

More to come!

John Moohread

[robert_cheal]

I thought that I would pick up this tread with a few questions about lathes on a SB.

Has any one used one of these cutting tips?

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It comes from one of these Delta duplicators.

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Could some tip holder be mounted on the Z axis?
I am wondering if light cuts would work or if it will place too much deflection & vibration on the Z axis.

Or the other idea would be a side mounted bracket for a router. Not really knowing anything about indexers I think it would be easier to create cutting files on th X & Y axis.
I just picked up a Cummins Tools wood lathe for $99 with cutting up to 14" Dia. & 38" long.
I am thinking that it could be dropped in along the Y axis of the table and mounted between the table supports, then removed when not in use and a section of the table could be dropped back in place for regular routing. I have some projects where a cheap lathe setup would likely do what I need. I am also getting ready to create a new table base so it would be nice to include this if possible. If anyone has ideas that could help I would be happy to hear from you.

Thanks, Robert

[jeff_guinn]

Robert,
I have the same lathe & copy attachment. The tool bits are positioned just below centerline like a metal working lathe & cut very well. There is quite a bit of downward force on the bit. A 90 degree router/grinder will probably be better suited for this type of work.
Jeff

[waynelocke]

I have been actively thinking about this for several weeks but have not done anything concrete. If anyone else has, I would also like to hear about it.

Wayne

[Brady Watson]

Robert,
Theoretically it should work if you set the tool in a proper holder and mounted it to the Z-axis t-rail. Light cuts are a given...

Keep in mind that you will have a CNC lathe at that point, and you will not have the ability for indexed parts like barley twists, 3D relief statues and things that you cannot do on an ordinary lathe. You should be able to use the indexer profiler & PW to make the toolpaths. I would recommend beefing up the Z axis to deal with the increased load potential and adding 4 more v-rollers to it (total of 8).

-Brady

[gerald_d]

Robert, in lathes, with those tips, you are mostly cutting across the grain of the wood. With a spinning routing bit, held to the side of the job (use y-axis to control profile, fixed z), you can cut more with the grain (but not get sharp inner corner detail)

[waynelocke]

I have been thinking of mouting the cutter on the Y gantry like Gerald suggests. The assembly would bolt on or off and should be fairly simple.

Wayne

[robert_cheal]

It is nice to see the comments from everyone. If I end using a horizontal mounted router I would have to touch up inside corners by hand. The other thought I have is either mounting a cutting tip holder or router bracket to the Y Car with the fixed cutting bit or tip location. The center axis of the lathe would the same Z location. What I would like to be able to do is to clamp or bolt on a special cutting tip or a separate router with out having to mess with my regular routing set up. I think that mounting to the Y instead of the Z would be more stable. Perhaps Brady's suggestion on another topic about using the appropriate 8020 aluminum on the Y car would enable a specially designed removable attachment.
I would also like to be able to remove a section of the table a drop in the lathe when needed or at least until I needed to turn a part more than 38" long. In building a new table surface I would also need to work out vacuum zones etc. with a removable section. One way or another I need to make an option for turning parts. I will post my progress but right now I am still gathering possible ideas. Any more are ideas and discussion would be welcomed.

Thanks for now, Robert

[jeff_guinn]

Robert,
If you decide to use a tool bit holder here is some Delta info-
Tel#800-223-PART
46-408 Wood Turning Duplicator(Main Unit)
Ram(Tool Bit Holder) #1344077
Tool Bit #46-415
Chip Guard #1344105
All parts are available seperately.
Good luck,
Jeff

[robert_cheal]

Jeff,
Thanks for the information. Based on your experience with Delta 46-408 would you do it mounted to the Y car on a PRT? Would the cutting forces be too much? And if you would do it,what would your cutting speed and depth per pass be?

With all things considered thus far I would be curious to know what Gerald and Brady (and for that matter anyone else)would do. Router or cutting tip?

An indexer would be nice but for right now a lathe set up would work out.

Thanks for now, Robert

[robert_cheal]

More thoughts...

Adding to my last post.
I wondering the following for a starting point.

After modeling the concept in Auto Cad I see that on the dust foot side, using the standard mounted router with a long 1/2" router bit (2" cutting egde), cutting from the side of the piece I can likely turn about 6" dia. if the corners are cut off on the table saw.

The lathe body would need to be mounted below the table surface with the axis up far enough to make contact withe the router bit. When needed I could clean up sharp inside corners by hand with standard lathe tools.

My primary use for a lathe right now would to make various parts for one of a kind architectural details that are then molded and cast in fiberglass resin.

As described would any of this lathe set up work?

OK, I'll shut up now.
Robert

[beacon14]

In know this is not exactly what you are looking for, but I purchased an extra router mounting bracket so I could easily swap the router between standard and horizontal positions. With the router up this high you might be able to just bolt the lathe on top of your table.
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[robert_cheal]

David,

Thanks for sharing the photo that is an interesting idea.

Robert

[jeff_guinn]

Robert,
I wouldn't use the tool bit on the PRT gantry because of the downward forces created by cutting(scraping).David has a good setup. You can mount a long shaft grinder(Makita,etc.) with a .25" collet instead of the router if you need more cutting depth.
Jeff

[robert_cheal]

Thanks to all,
I read over everyones responses again and I feel like all gave excellent ideas to consider. I can visualize a entry point into my lathe adventure. When I get back to the shop I plan on looking first into a solution along the lines of what David has posted. IT would seem to be the best starting point I can always refine and adapt as needs change.

One question though.
what kind of router bits? Ball nose, V-groove, Straight flutes?

Thanks, Robert