indexer/lathe combo for under $1K

[blackhawk]

Hello all - I just wanted to share my indexer/lathe combo setup that I recently completed for my 9648 PRT Alpha. I call it an indexer/lathe combo because I can easily switch between a stepper controlled indexer and a standard lathe ran by its own AC motor. I was able to get everything done for right at $900. That included buying the Rikon lathe brand new (on sale) and purchasing the Oriental motor and drive off Ebay. Luckily, I have access to a Bridgeport milling machine, so I was able to machine the stepper mounting plate myself. I also had to bore out the timing pulleys to fit the stepper and Rikon shaft on a metal lathe.

My pulley ratio came out to be 3.6:1 and on my first test piece it seems to be working fine. I can switch between indexer and lathe mode by just switching one belt on and one belt off. In the picture, I show both belts on just for clarity. The stepper belt takes a little effort to get off and on. I have it tightened just to the point where I can work it off the big pulley, but not have too much slack. In reality, I will probably use the indexer mode more than anything.

I really like the Rikon lathe. It can swing 12" on its own, but with my setup I can only do 8" because of the Shopbot table. I bought the extension bed and I can do about a 38" length until the tailstock hits the Shopbot rail.

If anyone wants some more specs or info, just post back to this thread. Randall's indexer tutorial really helped me out to get everything running. I probably would have never figured out everything without this forum. Pretty much all the knowledge to get this thing working was gained from all the posts right here. The piece in the last picture was my first test run.

[dana_swift]

Brad, that is an excellent setup. Looks relatively easy to do.

It clearly would have the advantages of a CNC lathe and indexer in one installation.

Supposedly "someday", SB is supposed to release a software update that allows the indexer to just have an RPM, so it can do both jobs directly.

Good work- and keep innovating-

D

[donclifton]

That really looks good. Woodcraft has that lathe on sell for 269.99. Very nice solution.
Thanks
Don

[jsooter]

Awesome. I really need to add an indexer to mine. That looks like a lot of cool applications

[donclifton]

I just ordered one for my router, I could not find the distance between the center and the bottom of lathe feet. Could you please give me that measurements I want to get things going while I wait for delivery. Any help would really be appreciate.
Thanks
Donald Clifton

[blackhawk]

Donald - I measure mine to be 13-1/2 inches. Let me know if you need anything else.

[donclifton]

Thanks Brad, I have some slates that came off an old Gerber router that I'm going to use to mount the lathe on. and I have 9" Z travel. I'm going to drop the slates down 9 1/2 inches from the table surface. Woodcrafter had the lathe on sell I got both lathe and ext. for $359 and free shipping. Thanks again for the help.
Donald Clifton

[donclifton]

Brad, Don't want to keep bugging you but what is the outside measurement of the legs front to back ( not bolt holes )? I'm rethinking my drop and will make it 13 1/2" instead of 9".
Thanks for the help I need all I can get
Donald Clifton

[blackhawk]

Donald - I don't mind at all, glad to help. The outside width of the legs are 7-1/2 inches. That measurement is the same for the lathe and the extension table.

Just in case you needed this measurement lengthwise...the main lathe feet are 27-1/2" and with extension is 55-3/4".

[donclifton]

Thanks Brad, that will help. I am tring to get the mount done before the lathe come. I have been using a Bayside gear head and it's a real pain to setup plus it just had a straight shaft. This way I can use a nova chuck or other attachment that will make like easier. Did you get your timing belts from McMaster?
Thank again
Donald Clifton

[blackhawk]

I got mine from mscdirect.com, but I'm sure McMaster sells them also. They are the XL style pulleys.

[donclifton]

Thanks I have bought from them also,can"t wait
Thanks again
Donald Clifton

[donclifton]

Brad, I decided to use gears to drive my indexer but other then that is just like yours. Works really well, This is a rocking horse leg I just finished made from western red ceder. It has 5:1 gear ratio and a 400oz hold nema 23 stepper motor.
Thanks for your help
Donald Clifton

[gene]

I really dont like you guys. LOL when i see you mcguiver type guys i feel so dumb! The indexers look fantastic as well as the projects. I am having a time with 3 axis's and you all throw in a 4th . I guess thats why i play checkers and not chess:rolleyes:

[blackhawk]

Donald - That looks good! How did you model the horse leg? Artcam?

[donclifton]

No, a friend of mine son is a 3D artist. I didn't use the lathe motor on mine, I figured the indexer could do anything I needed. I ordered a nova chuck for it today. Thanks for the help I have be wanted to do this for a while.
Donald Clifton

[donclifton]

Just wanted to post a link to my indexer cutting gears. I use to cut my gears on a knee mill but the router table works really smooth and a lot faster.
http://www.youtube.com/watch?v=lCehWAFQTYw
Donald Clifton

[frank134]

Ronald. I wanted to ask. what did you mount the leg to ? Is that aluminum and if it is where did you get it.
thank
frank

[myxpykalix]

Hey Donald,
Did i hear "Hi Grandpa" at 0:51 sec. ?

[donclifton]

The mount was made from 1/4" aluminum plate and the slates that the lathe is mounted to is T-Slotted slates from a Gerber Router. Yes that's one of five grandkids. I think one might even be a future botter.
Don

[road_king]

Brad,

Do you have the part numbers for the pulley and the belt?

Thanks,
Gerald

[blackhawk]

I bought both pulleys and the belt form MSC Industrial Supply. They are common parts, so any industrial supplier should carry them. The MSC part numbers are 35375864, 35376003, and 35369743. You can punch these numbers in on their website and it will bring up all the specs. mscdirect.com

[road_king]

Thanks Brad. I'll be ordering them today.

Gerald

[hunterland]

Brad which indexing motor did you buy off ebay and did you have any trouble setting it up with your shopbot. Thanks Don Hunter

[blackhawk]

I bought an AS98AA drive/motor package that included an ASM98AA motor and an ASD30A-A driver. I had to buy a ribbon cable and motor extension cable from Shopbot also. I was able to get both to work with a little help from Shopbot tech support. I had to use a certain combination of resolution settings to get the drive working correctly. I had no problems with the motor.

Shopbot buys their drives from Oriental with special programming, so if you buy a drive from somewhere else there are a few differences. Like I said, I played around with my drive and got it to work fine. You can also send the drive to Shopbot and they can program it to their standards for around $15.

[gene]

I wonder how much the motor / driver and electrical hook up items are from shopbot? I like this lathe setup that is a lathe as well as an indexer

[myxpykalix]

As Dana said early on in this thread:
"Supposedly "someday", SB is supposed to release a software update that allows the indexer to just have an RPM, so it can do both jobs directly."

It has been a year or two since this has been talked about with no action so far (as I know)...so if you are thinking about setting up an indexer i'd go ahead and setup a lathe motor rather then waiting for the software update:rolleyes::mad::D:( lol

[gene]

I cant remember the thread but there was talk of the motors getting very hot after an extended run time. That is why i would prefer this type of setup . Then you use the lathe motor for its designed purpose turning anr roughing to a cyclinder and the indexer motor for its designed purpose of small incremental turning . I am NOT a very mechanical person for trouble shooting so if the electrical came from shopbot and the rest from another suppiler , or both from shopbot then i would feel more secure with this type of setup:confused:
I hope that makes sense :rolleyes:

[myxpykalix]

Gene,
I don't think that we are talking about an extended turning times to complete most of these parts. If you go to this video:
http://www.legacycncwoodworking.com/demo-videos/
go down to:
Turning Demo - Combining machining, turning and carving techniques (http://www.legacycncwoodworking.com/demo-videos/2010/10/14/turning-demo-combining-machining-turning-and-carving-techniq.html)
and watch the way those turnings are made with a large diameter core box bit you'll see the stock isn't turning any faster then on a shopbot and this to me is a far faster and superior cutting strategy for symetrical turning then with a small bit running up and down the piece bumping one degree at a time, ect.
And the finish is almost good enough to not have to sand the part. I have made parts on my manual legacy that can be done faster then on the shopbot (in some cases).

[gene]

I have a legacy with the motor for turning the parts but i havent used it in a long time. They sure have came a long way with their machines. I like the auto change spindle . that could save alot of time .

[myxpykalix]

I have a 900 with the turning motor prox switches and just about every add on they had at the time. I'd like to sell the whole shootin match. I've been trying to figure out how i could adapt my rotating table to the indexer.

[plemon]

Hey Donald,

That does look great. I've been needing an indexer and that looks just the treat. Two things though,

Is that a playstation controller I see in one of your pictures?

Also, what type of hold down system are you using for your table?

Phil

[dougo]

Brad, I am working on an indexer that is going to be setup like yours. Could you show more pictures of how you have the plywood mounted to the Shopbot that the lathe is mounted on and also of how you have the stepper motor mounted to the lathe?

thanks,
Doug

[blackhawk]

Doug - Here are a couple of pics. The first one shows how I attached the plywood deck to the Shopbot legs. I used two pieces of uni-strut and attached one to the front and one to the back of the Shopbot legs. I just bolted down through the plywood into the uni-strut. I was just barely able to get a nut up inside the uni-strut.

The second pic is a 3D view of the CAD model that I used to setup the motor mounting. The dark grey 90º motor mount was purchased directly from Oriental Motor for less than 20 bucks, well worth it. The base plate in light grey was machined by me on a Bridgeport knee mill. I drilled and tapped holes into the Rikon lathe and then bolted the base plate down to the lathe with 4 socket head screws. I have a dimensioned drawing of the base plate if you are interested.

[dougo]

Thanks for the pictures Brad and I would appreciate the drawing of the base plate. I am going to need any help I can get.

[bob_dodd]

I wanted to thank Brad for shareing all the info , I'm also in the process of putting togather a lathe / indexer , Just waiting on the motor mount from Oriental motor . I needed to extend the X aluminum extrusions and rails 8 inch to clear the cnc table . I also enlarged the pulley bore on both to make fit the shafts , I machined the 3/8" thick aluminum plate that the stepper mount will attach to , on the cnc with a .250 up cut end mill @ 3" a sec. & .003 step down ,
11850

11851

[bob_dodd]

needed more room
11852

11853

[Brady Watson]

What's nice about using a lathe is that it has a real headstock with bearings suited for turning. I never liked the idea of relying on the stepper's gearbox bearings to take all the thrust & radial loads.

-B

[kurt_rose]

Hi guys. I just finished installing a Harbor Fright lathe and am very unhappy with the piece of junk. should of known better. How do you guys running the Rikons like it when running it as a cnc lathe. How deep of a cut and at what speeds are you running? My current project is a good size spindle from 4x4 cedar. talk about tear out!!! I'm just trying to get everything dialed in and have the Rikon on the way. Any input would be greatly appreciated. Thanks in advance ,Kurt

[frank134]

Hi Bob Can I ask where you got the added rail from. I like to move my indexer father out the back like your. so I need to extend my rail like you.
thank frank

[bob_dodd]

Frank , the aluminum flat stock is from 8020 , i machined the countersunk mounting holes with the cnc , the hardened rails are Bishop Wisecarver #2 you can get it from http://www.cadcamcadcam.com/cncmachinecomponents.aspx

The rack gear is .5" x .5" I think the pitch is 20 but I'll have to check as I've had the rack gears a year or so now Bob

[frank134]

thank you and if you can get back to me on the pitch that would be great. who did you get the 80/20 from?

[bob_dodd]

Frank the aluminum stock & extrusion i got on ebay from 80/20 , I'll check later today about the pitch when I get back into the shop Bob

[bob_dodd]

Frank you have a PM

[GioAttisano]

I'm currently setting up an indexer/lathe combo for my shopbuilt CNC router. I'd like to know what rotational speeds you guys with lathe modes have found useful for what type of work (diameter, wood species). I"ve been thinking slow is where its at, actually buying a grearmotor to give me 40-200 RPM, but unsure if that makes sense. Thanks!

[Brady Watson]

In lathe mode, you want to go a lot slower than you would initially think. Keep in mind that at 1 revolution per second (60 RPM) on a 3" diameter part, the bit is effectively cutting 3 X pi (3.1416) or about 9.5 inches per second(!)

My recommendation is to gear things down for max torque at low rpm, and a max RPM of about 300, to get the most versatility.

-B

[MogulTx]

I am setting up a Rikon to go on my machine. From your photographs, it looks like you guys set it up so that the centerline of the turning is relatively close to the Z zero for the machine. I am designing the structure that will hold the lathe at the moment- which will define where that centerline rests... and I am thinking that I will set my centerline about 1" below table bed, on the assumption that I will always have some material at the center of the piece I am turning, which will not be removed, so I will rarely get to the center line of the part with my bit, and the machine should be able to be set up to reach the center line anyway... is this about how you guys see things?

Thanks

MGM

[Brady Watson]

Set it lower than you think you need if you are going to be cutting 6" or greater dia parts. Drop that Z all the way down and then put the CL about 2.5" below that. If you HAD to, you could get all the way down to the center with an extra long cutter. Aside from this, most of your work will be from the top, so you need to account for bit length. Also consider if you would be machining off to the side, spinning and using the tool like an outside profile toolpath. I do about 99% from the top/apex of the workpiece.

-B

[Wildman]

I love your setup, I also have a Shopbot PRT Alpha and want to add a inder / lathe setup like yours, do you have the parts list you used to get your system up and running, and where you purchased them from?

Thanks

Jim Wildman

[blackhawk]

Jim - See posts #22 and #25. The only other parts are custom machined plates that I made out of aluminum.

[jon]

@blackhawk; Great set up! I have a few ASM911AADC2.65v motors and drivers leftover from my upgrade to ASM98AA-T7.2 motors and drivers. If I were to use the original ASM911AADC2.65v motor and driver to control the lathe, do you think its possible to source a pully set and timing belt combo to reduce my servo motor's rotation from 1:1 to 20:1 like Brady Watson suggests?
Does anybody have any experience with this, or could suggest a source?

Thanks, Jon

[blackhawk]

Jon - The belts and pulleys come from mscdirect.com. Just go on there and look to see if they have a pulley combination that will work for you. The part numbers that I used are in this thread if you search back several posts.

[sbd1]

Very helpful info Brad, thanks for taking the time to document & share it! I'm looking into setting up a lathe/indexer just like yours on my PRTalpha, but I've got to bring myself up to speed with a few technical items first. Hopefully some of you guys can enlighten me a little.

1) Gear ratio: I believe you said yours is 3.6:1, and in other posts people have mentioned using 5:1 and 18:1. Can anyone explain the consequences (other tan smaller steps & higher speeds) of these to me? Is it simply a matter of configuring the SB control software to match the gearing I want/have?

2) Motor, driver & cables: My X, Y & Z axes use Vexta ASM911AA motors with ASD30E-A-B1 drivers. I believe you used an ASM98AA motor and an ASD30A-A driver. I've been quoted a price from Shopbot for new motor, driver & cables, but because I'm in Canada the shipping & the current exchange rate make it fairly pricey. And it seems like Oriental has discontinued that exact motor, but I don't understand the significance of the part #'s, so maybe it's not important anyway. Can I just use the same motor & driver as you?

3) I could buy the ribbon cable and motor extension cable from Shopbot like you, but if I use the same motor/driver as you, would you be willing to share your "certain combination of resolution settings to get the drive working correctly" that Shopbot helped you with?

Keep up the good work eh.
Daren

[blackhawk]

Daren - Below are some answers for you.

1) The higher the gear ratio, the higher your resolution will be. You will also gain more torque. The drawback is that you lose speed at the indexer. You would really have to investigate the speed/torque curve of the motor and calculate your cutting torque to gain a real understanding. I think anything between 3 and 10 would be fine.

2) You may have to use the ASM911AA and ASD30E-A-B1 on yours since this matches what your currently have. I am not sure that you can mix in different drives in the control box. You could check with Shopbot. You can find these on Ebay most of the time.

3) You are going to need the ribbon cable and extension cable no matter what you do. The easiest way is to buy these from Shopbot. You'll spend way more time and money trying to get them elsewhere or make yourself. The resolution settings don't have any thing to do with the cables. These are calculated numbers based on your setup. Here is a link of an old post that I had that will help you some. http://www.talkshopbot.com/forum/showthread.php?17518-Formula-for-Unit-Value-calculation&highlight=resolution

[sbd1]

Thanks for sharing what you know about this with me Brad. It's obviously much more than I do, but like most of these things, once you've learned it they're actually pretty straight forward. I just noticed that Jon in BC said that he's got a few of the same motors as I do left over, so I'll see if he wants to part with one of them.
Cheers

[hunterland]

Hello Don what model Rikon lathe did you use for your setup. I know this is an old thread thanks Don

[blackhawk]

I used the 70-100 model Rikon lathe. Brad