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View Full Version : Designing a 5c indexer--compromises, compromises. . . .



Jim2
12-29-2013, 04:32 PM
I'm wanting an indexer for holding small parts while machining on the mill and shaper. The mill is a Rong Fu-45 clone, and the shaper is a 7" Porter Cable (predecessor to the Logan 7"). I'd like to be able to tilt the work and have it fit on the shaper, which is quite small.

Anyway, here's what I came up with first:

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-003a_zpsb47a8255.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-003a_zpsb47a8255.jpg.html)

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-003b_zpsb8267cdb.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-003b_zpsb8267cdb.jpg.html)

The drawing shows a 1 7/16" OD worm w/ 3/4" diameter shaft. That uses up a lot of vertical room, but even so the design fails for lack of a locking mechanism to hold the work while milling. There is an eccentric "backlash adjuster" on the spindle that was difficult to fit in there with that over-size worm. Even with a right-sized worm, I'm unsure of how to get a lock on the spindle. I guess a clamping mechanism on the exposed lip could work, but it wouldn't be particularly elegant.

I think the best thing that can be said for this design is that there is a minimum of space between the work and the machine tool that will be working on it.

Well, at that point it was back to the drawing board. I wanted something physically smaller w/ less complexity. Plus I found jhe.1973's thread http://bbs.homeshopmachinist.net/threads/60225-Modified-Spindex which showed me how to source better gearing than what I had found on Ebay. There were lots of other good ideas in there, too.

Here's where I'm at now:

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-004a_zpsdad7cabb.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-004a_zpsdad7cabb.jpg.html)

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-004c_zps6f389c83.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-004c_zps6f389c83.jpg.html)

I've got a split-cotter here that locks the main spindle, so the locking "requirement" is satisfied. Going to the trunnion-style tilting mechanism results in a smaller overall size and a simpler design.

One problem that I see here, are that the dividing plate is way up there--interfering with the milling head or whatever--when the work is held horizontal.

Other concerns that I have is that the part that holds the worm and dividing plate may be difficult to make since it would require a 5/16" hole to be drilled 5 3/4" deep. Also, I'm not sure if I should be thinking about using some special materials or bearings on the rotating shafts, spindle, etc. I'm not sure if the pay-off in terms of usability or reliability would be worth it considering my skill level and the amount of use this device is likely to get. . . .

So, I'm wondering if anybody has any ideas to improve on either of these designs? Is there another design out there that might be better? Keep in mind that I'm a perma-noob that spends my days at a desk. This is a hobby for me, so I don't have access to lots of exotic tooling or the experience that many of you do. I can weld but not real well--stick only--so I'm trying to come up with a design that doesn't require that.

I've got more pics at http://smg.photobucket.com/user/jasch/library/Metalworking/5c%20Indexer?sort=9&page=1

thanks,

Jim

J Tiers
12-29-2013, 10:46 PM
I understand that you want to build this.

1) A number of years ago, HSM published a dividing head project by a now-deceased author who also did many many odd engines.
it could be scaled up as needed, or left as-designed. The spindle nose could be varied to suit your needs.

If necessary, I can go find the article and let you know author etc..... it is likely still available from VP.

2) of course, many makes of dividing head will do this job now, and be an appropriate size. I have an L-W which fits a 4" wide table.

3) You probably really want a rotary table that comes with a set of index discs for dividing useage. There are several brands out there with sizes of 4", 6", 8" etc table diameter.

Any of them will leave you lots of daylight under the cutter. Far more than any dividing head style unit. And many have the ability to use discs for indexing when turned up with axis horizontal.

Jim2
12-30-2013, 10:26 AM
I understand that you want to build this.

Yeah, it's cold up here in the northern tier. Without a reason to get out in the shop, I'll sit in the house all winter and get fat.




1) A number of years ago, HSM published a dividing head project by a now-deceased author who also did many many odd engines.
it could be scaled up as needed, or left as-designed. The spindle nose could be varied to suit your needs.

If necessary, I can go find the article and let you know author etc..... it is likely still available from VP.

That sounds interesting. I've ordered back issues before to get plans for a project. I looked at Ishimura and Google images, but didn't find much.




2) of course, many makes of dividing head will do this job now, and be an appropriate size. I have an L-W which fits a 4" wide table.

I've checked out Shars, Enco, and haunted Ebay for a while. Most of the units with the features that I want are either too large, too expensive, or of very questionable quality. I keep thinking I could make something better if I had the right design to start with.

Where did you get your dividing head? Are there any dividing heads that come with 5c collet? I just bought a 4-jaw chuck w/ a 5c mount, so I'm thinking this would give me the versatility that I want.




3) You probably really want a rotary table that comes with a set of index discs for dividing useage. There are several brands out there with sizes of 4", 6", 8" etc table diameter.

Any of them will leave you lots of daylight under the cutter. Far more than any dividing head style unit. And many have the ability to use discs for indexing when turned up with axis horizontal.

I've seen some, but most don't tilt. I thought about buying a tilting table or adjustable angle plate, but they just take up more room, and quality seems to be questionable on the ones I was shopping. I've got an 8" with the dividing plates, but it is too large for the shaper.

I had been thinking of buying a spindex and small tilting table, and then doing some mods. I understand they're not really designed for milling, but it would be sized right for the shaper I've got. An 8" rotary table just isn't going to work with that at all.

Jim

Stepside
12-30-2013, 11:40 AM
Jim

Here are pictures of the indexer I built for my small CNC mill. To give an idea of size, the chuck is 3 inches in diameter.

The good news is that it does not require a worm gear. The bad news is it requires different plates for different gear counts.
http://i1148.photobucket.com/albums/o563/72stepside/DSC_0451.jpg

This is an early picture, I have made a couple of modifications that make it more rigid. As it is built, it will tilt in excess of 45 degrees.

Pete

Timleech
12-30-2013, 12:11 PM
I have an early Haas 5c indexer, which is based on an ordinary spindex type unit but with stepper motor drive via worm and wheel. Have you looked at the possibility of adding worm drive to a cheapy spindex?

Tim

Alistair Hosie
12-30-2013, 12:21 PM
I Hve one of these from the american owned co.jbs cheap and cheerful does a great job so why unless it is going to bring you pleasure would you make one albeit yours does look good anyway I wish you fun with it Alistair

Timleech
12-30-2013, 01:38 PM
Here's a style of indexer that I haven't seen another example of. Intended for grinding, I have used it for very light milling jobs but wouldn't dream of putting it near a shaper.
It would fulfil some of your criteria, but not rigid enough 'as is'.
Adjustable to any angle in vertical & horizontal axes, and 20 & 24 hole indexing rings on the spindle as well as clamping at any angle.

http://i559.photobucket.com/albums/ss38/Timleech_2009/Workshop/Habitindex-1_zps90cea72e.jpg (http://s559.photobucket.com/user/Timleech_2009/media/Workshop/Habitindex-1_zps90cea72e.jpg.html)

http://i559.photobucket.com/albums/ss38/Timleech_2009/Workshop/Habitindex-2_zpse5775e87.jpg (http://s559.photobucket.com/user/Timleech_2009/media/Workshop/Habitindex-2_zpse5775e87.jpg.html)

Tim

Jim2
12-31-2013, 11:27 AM
Sometimes I kinda get tunnel-vision when I'm working on something like one of the drawings above. I shoulda been doing my homework first, maybe. Yesterday I googled "dividing head plan", and came up with a couple of designs that might get me closer to where I want to be. Check this out:

http://www.youtube.com/watch?v=j8_rduPVM64

This guy made a very nice, compact little unit out of a chunk of aluminum w/ brass bushings. I would be pretty happy with it--just a few mods and it would have the 5c spindle I want.

This other guy made his dividing head into a universal unit by bolting some disks on the sides and making a base!

http://homemadeindexinghead.blogspot.com/


Hmmm. . . . Maybe these two ideas might work pretty well together? I'd have a compact unit with the versatility I'm looking for. I guess it's back to the drawing board.

Now, there are a couple of other questions that I don't have straight in my mind. The designs I'd worked on earlier allowed for taking up the lash between the worm and the wormwheel. I don't see that feature in the youtube clip above. Maybe that's something that I shouldn't bother with? Also as far as bearing material goes--my understanding is that bronze would be best, but brass would probably be fine for the type of usage I'm talking about. . . . Any thoughts on this?

Jim

PStechPaul
12-31-2013, 11:47 AM
I found a spindex on eBay for pretty cheap, missing some parts that might be enough to keep you busy:
http://www.ebay.com/itm/NEWS-YUASA-5C-SPINDEX-SPIN-INDEX-GRINDING-MILLING-FIXTURE-JIG-MACHINIST-TOOL-/221344370070

Jim2
12-31-2013, 12:16 PM
I should get one of those just so I'd know what everyone is talking about. Do you have one?

Jim

PStechPaul
12-31-2013, 02:11 PM
No, I don't have one, but I do have a rotary table. I bought it about ten years ago and never used it. It was still in the original shipping box (falling apart from dampness and mildew), and sealed in plastic. I figured it was time to take it out and see if I can really use it. A dividing head may actually be more useful, or perhaps a "spindex"?

http://enginuitysystems.com/pix/Rotary_Table_0735_800x600.png

http://enginuitysystems.com/pix/Rotary_Table_0734_800x600.png

http://enginuitysystems.com/pix/Rotary_Table_0736_800x600.png

Jim2
12-31-2013, 03:51 PM
That looks like a nice one. You sure could have done a lot worse--trust me!

Jim

PStechPaul
12-31-2013, 04:38 PM
It still had the receipt with it. $184 including shipping:

http://enginuitysystems.com/pix/Rotary_Table_0737_800x600.png

Just about the same thing is on eBay for $230 with shipping:
http://www.ebay.com/itm/6-Horizontal-Vertical-Rotary-Table-/271355534372

It might be good to have a dividing plate for it. Perhaps these would work:
http://www.ebay.com/itm/Dividing-plate-for-6-8-10-and-12-rotary-tables-/180856888044
http://www.ebay.com/itm/Dividing-Plates-Set-for-HV4-HV6-Rotary-Table-with-its-working-manual-/221328737014

Maybe I should contact the original seller. They seem to be still in business, although maybe not on eBay:
http://toolsupermarket.com/

Jim2
01-01-2014, 10:09 AM
The second set that you referenced (3 plates, made in India) looks to be the same set that I have. Mine are nominally 4 1/2" in diameter. The sector broke without ever being used. Here's a pic.

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/IMG_4206_zpsc7c44a38.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/IMG_4206_zpsc7c44a38.jpg.html)


These plates were supplied for use with a Rotary table that has 90:1 ratio (4 degrees/turn). I think they will work just as well w/ most any ratio. I plan to use them on my dividing head.

I'm working on another design, and will probably post some pics within the next few days. . . .

Jim

Weston Bye
01-01-2014, 11:34 AM
Here is what I will be presenting in the upcoming issue of Digital Machinist. I have a lot of Sherline tooling so I designed the spindle to accept the tooling. Threaded spindle for chucks and faceplates and #1 Morse taper for collets. 40:1 worm gear, stepper driven.

http://img.photobucket.com/albums/0803/Weston/A-Indexer_zpsf9663b8c.jpg

Jim2
01-05-2014, 07:52 PM
That's very nice, Weston. You're in playing at a much higher level than I am. I'm not ready to go to CNC yet, either.

Here's where I'm at now:

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-005a_zps85f35a26.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-005a_zps85f35a26.jpg.html)


Another view:

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-005b_zps4eb703bb.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-005b_zps4eb703bb.jpg.html)


Here's some detail of what I plan to do with the spindle:

http://img.photobucket.com/albums/v280/jasch/Metalworking/5c%20Indexer/5cIndexer-005c_zps93f1e84e.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5c%20Indexer/5cIndexer-005c_zps93f1e84e.jpg.html)


I'm planning to do the body very similar to the way that other fellow on YouTube did it.

http://www.youtube.com/watch?v=j8_rduPVM64

I'm planning on keying the wormwheel to the spindle, and using retaining rings to hold it in position. The red ring dealy at the back is a nut that will be threaded to the spindle with a bolt to lock it in position.

I'd like to put a grease zerk on there somewhere and fill the body with grease, but I'm concerned that my lock won't be very effective if grease gets in there. Will the split-cotter be effective with grease in there? Should I forget about the grease? I could just put a gits oiler or the like on instead. Is there a better way?

D@#^!, the Packers just lost to the 49ers. . . .

Jim

trackfodder
01-05-2014, 10:06 PM
I just bought an indexer and angle plate from Wholesale Tools that is adequate for my needs and very sturdy. Not as much fun as building one, I guess. Whatever floats your boat.

J Harp
01-05-2014, 10:29 PM
Wayne Hanson built a nice looking one. The build write-up starts in HSM Volume 20, Number 3, May/June 2001.

Philip Duclos built another nice one. The article is in one of the books offered by Village Press. I don't recall if it's in one of the Projects books, or in one of the Metalworking series.

Jim2
05-06-2014, 09:37 AM
Well, I actually built the indexer! With a little further inspiration from jhe.1973 in http://bbs.homeshopmachinist.net/threads/60225-Modified-Spindex?highlight=amazon+worm, I was able to source some gears from Amazon, and come up with a design. Here are a couple pics

http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4568_zps0af186e1.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4568_zps0af186e1.jpg.html)


http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4574_zpsb0a37bd7.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4574_zpsb0a37bd7.jpg.html)


http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4575_zpsa2ca9e76.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4575_zpsa2ca9e76.jpg.html)


http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4576_zps77504cc0.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4576_zps77504cc0.jpg.html)

Jim

Jim2
05-06-2014, 09:37 AM
Here are a couple shots with everything buttoned up and the last one using simple indexing to make a 4-sided nut.

http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4605_zps9ac0464f.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4605_zps9ac0464f.jpg.html)

http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4606_zps68788262.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4606_zps68788262.jpg.html)

http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4608_zpsfe2b845c.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4608_zpsfe2b845c.jpg.html)

http://img.photobucket.com/albums/v280/jasch/Metalworking/5C%20Dividing%20Head%20Final/IMG_4602_zps6697f7ce.jpg (http://smg.photobucket.com/user/jasch/media/Metalworking/5C%20Dividing%20Head%20Final/IMG_4602_zps6697f7ce.jpg.html)

The indexer features both simple indexing via the pin accessed from the "back", and direct indexing with the worm, worm-wheel, and indexing plates. The worm shaft is a two-piece affair. One end has the crank. The other end is threaded into a sleeve that rotates within the body of the indexer. This "sleeve" has a knob on the side of the indexer opposite the crank. To utilize simple indexing, the worm is dis-engaged from the worm-wheel by disconnecting the crank end of the worm shaft from sleeve and knob end of the shaft. The spindle is then free to turn in the body of the indexer.

So. . . . What have I learned? Well, I probably would design a different styled spindle lock if I had it to do over again. The split cotter seems to be quite effective. It's just that it sticks, which makes it a pain to use. I actually had to re-design half of the split cotter, so that the loosening action would "un-stick" one half of the split cotter, and then you have to hit the lock lever with your hand or mallet or something to release the other side. Like I said--it could be better, but it seems like it locks the spindle pretty well, and it is compact--so it could be worse.

All in all, this seems to beat the collet blocks I had been using!

Jim

RichR
05-06-2014, 10:52 AM
Hi Jim2
Very nice workmanship.

The split cotter seems to be quite effective. It's just that it sticks, which makes it a pain to use.
Mark the surface of the split cotter that grabs the spindle. Reassemble and work the lock a few times. Check the cotter for a shiny spot. Thats probably where
it's sticking.

rowbare
05-06-2014, 11:10 AM
Very nice work!

bob

Jim2
05-06-2014, 02:05 PM
Thanks, for the compliments.




Mark the surface of the split cotter that grabs the spindle. Reassemble and work the lock a few times. Check the cotter for a shiny spot. Thats probably where
it's sticking.

I had the cotters in place when I bored the hole for the spindle, and the finish seems to be quite good. I think the taper involved is just too small--a design issue, not an implementation problem. . . .

Jim

Jaakko Fagerlund
05-06-2014, 03:22 PM
Jim, could you install spring between the cotter halves?

RichR
05-06-2014, 04:22 PM
Hi Jim2
[QUOTE]I had the cotters in place when I bored the hole for the spindle, and the finish seems to be quite good.[QUOTE]
I had presumed that much. If you try my suggestion, it would not surprise me if you saw a shiny spot near where the two cotter halves met.

Jim2
05-06-2014, 05:27 PM
Hi Jim2

I had the cotters in place when I bored the hole for the spindle, and the finish seems to be quite good.
I had presumed that much. If you try my suggestion, it would not surprise me if you saw a shiny spot near where the two cotter halves met.

You may be right! I had to make a replacement for half of the split cotter because I messed up the original when I made the release mechanism. It seems like the replacement doesn't "stick" like the original does. I guess it may have slightly more clearance on the flatter portion of the curve than the original.

Unfortunately it is quite a chore to fish that other half of the split cotter out of there. The support is pinned to the base, and one of them must be removed to access a setscrew that holds the bushing for the spindle. I'm not sure that I want to go through all of that just yet. I'm going to keep that in mind though as I'll probably end up tearing it down at some point before too long.

Jim

Jim2
05-06-2014, 05:28 PM
Jim, could you install spring between the cotter halves?

No, there's no room in there. It is quite stubborn in any case, and would take quite a substantial spring to loose it.

Jim