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View Full Version : enco angle table--sloppy fit and backlash



mikem
12-31-2008, 09:33 PM
Just got a 5 by 7 inch Enco angle table for $65 on sale. I thought that it would be good to be able to cut angles without having to move and then re-tram the head on my Bridgeport mill everytime. It tilts 45* one way and 15* the other.

The table looks good but the crank wrench for the angle adjustment is very poorly made and between the sloppy fit of the wrench and the backlash of the worm gear that moves the table, it takes about a quarter turn to get the table to reverse direction.

Is this normal? Is this going to be a pain to use? Should I have spent more money and gotten a name brand?

dp
12-31-2008, 09:37 PM
I bought a cheaper one without the crank just to avoid that issue. It required a bit of machining on arrival but works great. I think Tiffie has one similar to yours, crank and all.

SGW
12-31-2008, 09:44 PM
It sounds like you got what you paid for....

Whether it's usable in a reasonable way only experience will tell, I expect. Backlash, per se, is not necessarily a problem. All leadscrews have some amount of it. More important, probably, is whether or not you can tilt the table and maintain alignment perpendicular/parallel/whatever without slop in the bearings. Even that may not be a show-stopper if you have patience in doing the setup and don't try to tilt the table while you're actually milling.

Presumably this thing is going to see infrequent use? Personally, I think I'd probably use one a couple times a year. If you're going to be using it a couple times a week, after a few weeks you may decide you want something better.

lazlo
12-31-2008, 09:47 PM
It sounds like you got what you paid for....

I bought the same tilting angle table a year ago, and it's junk:

Send It Back? (http://bbs.homeshopmachinist.net/showthread.php?t=24049&highlight=send)


As you say, the surface of the table is nicely ground, and the fit into the curved ways is actually pretty nice. What's really disappointing is the worm-drive is really, totally, completely crappy. It's got backlash of at least a half turn of the crank. A lot of that is really sloppy fit between the worm and the worm wheel (the base of the table), but a lot of it is from a very primitive set of pillow blocks that hold the worm. The pillow blocks I can replace, but from playing with it, most of the backlash seems to be in the loose fit with the worm -- is there any cute way to fix that other than cutting a new, non-standard worm to fit the worm wheel cut into the base?

J Tiers
01-01-2009, 12:03 AM
That seems to be the downfall of many similar products..... bad fit on screws etc. You may be able to fix and use it, if you determine what the issue is. For your price, you can afford to spend a little time and stil be below a really nice one, pricewise.

handle and bearing portion of one screw from an x-y table I bought from J&L for a similar price (and which I fixed and am using happily). The bearing area is the rough part to the left. The dial was attached to the area with the left-hand pin hole, and the handle with nut at right.


http://img.photobucket.com/albums/0803/jstanley/chinlead.jpg

lazlo
01-01-2009, 12:13 AM
The biggest problem with the gigantic backlash on the worm feed, and why I really wish I had gotten the plain table (without the worm feed), is that when you release the lock bolts, the whole table drops 20 - 30. That's really annoying when you have a heavy workpiece bolted to it.

Mike: another thing you might need to check: the T-slots are out badly on a lot of these tables. If you read through my thread, I had Enco send three replacements, and each was worse than the previous. I ended up keeping the first, rusted table, because it had the nicest T-slot top on it. The others either had wonky T-slots and/or voids in the table top.

oldtiffie
01-01-2009, 12:38 AM
I have two worm-driven tilting angle-plates - a 7" x 5" and a 7" x 10". The worm is a bit "sloppy" (very actually) on the smaller but OK on the larger.

The condition of the worm doesn't matter at all. What ever its condition as long as it works its OK. It only has two jobs to do:

1.
not to "run-back" and so hold the load where you set it; and

2.
to be "fine" enough to set the angle you require and stay there until you clamp it.

I had to completely re-machine my 5 x 7 (other than the "cylinder") as everything was "out" by between 1.00mm (0.040") and 0.10mm (0.004"). It was a good machining project and it is now as true as my mill could make it - and that is very good. I left the worm drive as it was - with all the "slop" in it as it works very well. I couldn't see the need to "do it up" even though it was quite "do-able".

I only bought the larger one because the smaller one was a bit "small-ish" for my purposes but other than that it is now excellent. I have yet to see how good or bad it is, but what-ever the condition, I expect that I will (re)machine that one too.

The 7 x 10 will take a 6" rotary table easily.

Those tilting tables are an excellent acquisition for the shop as they solve a lot of "tough" set-ups and can really save "space" - particularly "Y" - on a mill.

I have to say that the cast-iron was really first-class - beautiful to machine and a very good finish.

As a matter of practice, I always assume that I am going to re-machine my vises angle plates ant tilting tables etc. I just need a "seasoned" pre-machined casting and off I go. If it needs no machining, I am "in front", and if it does need machining I am satisfied as well.

lazlo
01-01-2009, 12:51 AM
The condition of the worm doesn't matter at all. What ever its condition as long as it works its OK. It only has two jobs to do:

not to "run-back" and so hold the load where you set it;

Yes, it does matter. The worm drive is so sloppy that it's worse than useless. There's so much slop in the worm drive that it "runs back" 20 - 30 when you release the lock bolts. This was the same on all four tilting tables that Enco sent me.

I really wish I had gotten the plain version of this table, because the worm drive takes away 30 of travel on one side already, and since it doesn't work...

mikem
01-01-2009, 03:05 AM
thanks guys. I wondered if it was just my table. It sounds like they are all bad. I'll try to check it out more tomorrow and report back.

BadDog
01-01-2009, 04:30 AM
I was just lucky that Robert (lazlo) and others posted experiences preceded my purchase. Based on their feedback, I bought a non-screw version and I like it very well. It works rather well and retains tram well enough for typical work, though it has to be dialed at the desired angle if it "really matters" to the thou. Over all, it was worth easily what it cost. And if I ever get around to working on my scraping skills, I'll take that "casting kit" and fix 'er up right... :D Lots cheaper than some raw casting kits, so I figure I came out pretty good...

oldtiffie
01-01-2009, 05:56 AM
Originally Posted by oldtiffie
The condition of the worm doesn't matter at all. What ever its condition as long as it works its OK. It only has two jobs to do:

not to "run-back" and so hold the load where you set it;


Yes, it does matter. The worm drive is so sloppy that it's worse than useless. There's so much slop in the worm drive that it "runs back" 20 - 30 when you release the lock bolts. This was the same on all four tilting tables that Enco sent me.

I really wish I had gotten the plain version of this table, because the worm drive takes away 30 of travel on one side already, and since it doesn't work...

I just checked my smaller tilting table. It has about 1/5 turn of back-lash and doesn't "run backward" under load if I free the tilting table clamps (which are the weak point as a heavy load tilted too far is hard to restrain unassisted). My "machinists jacks" or similar soon fix that. I don't even try to tilt past 15 degree on the side where the worm spindle extension is as it gets in the way of the supplied crank lever - although I use standard 1/4" square sockets on it. They are not made for heavy tilted loads and/or "hogging" - and few tilting tables are.

Its no different to the worm in the tilting head of a mill - and a few others.

I just wind it - or let it run- back and then take up the back-lash under load, bring it to where I want it to be, clamp it, check it and if OK - away I go.

Countering or allowing for back-lash in many things is just part of life in a shop - its a matter of making what you have work for you.

We don't live in a perfect world although what we have - or more particularly what I have - is good enough to do quite well.

I had a "non-screw" tilting table and it was the biggest mistake I made as it never pulled up "tight" and by the time I had "adjusted" the "pillars" it was way out.

Many tilting tables rely on a central bolt (or two) to hold the angle, but that is a lot of leverage when you get past 15 degrees.

Seriously though, once you get past 45 degrees, you have a problem and need to re-think your set-up.

I bought mine for several reasons:
- to mount a vise on so as to deal with plain angles without tilting my mill head;

- to mount the vise on so as to use it for compound angles without tilting my mill head;

- to have a "tilt-able"/angular smaller slotted table;

- it it much easier to set an angle on than using a rotating base on a vise;

- it solves the problem when a "nodding" mill-head would be handy or needed but isn't available.

- I can easily set it as accurately as my protractors will allow - 0.10 arc degree (6 arc seconds = 0.0017" per inch) - I can set it much more accurately if needs be - particularly if the angle is a multiple of 1/4 arc degree using my precision angle blocks. Mine are similar to these at:
http://littlemachineshop.com/products/product_view.php?ProductID=2553&category=
except that mine go down to 1/4 degree and will "wring" together - "Vertex".

I don't have, don't need and don't want a sine bar as I can make anything I need correct to 20 arc seconds (0.0001" per inch) - or better, on my rotary table/s.

- it is easy to mount an angle-plate or a "Spindexer" or a whole lot of other "stuff" that requires "tilting" that will almost anything else.

The tilting table should be a part of the kit for any/most shops.

Your Old Dog
01-01-2009, 07:36 AM
My 5x7 Enco has a lot of slop but it does all I need it to do. I just need the Worm to hold the table where I want it until I get the screws tightened up. It would be nice to have a velvet feel but not at the prices I'd have to pay for backyard home shop use.

aboard_epsilon
01-01-2009, 09:02 AM
I don't understand this problem ...arent you supposed to lock the table once you have arrived at the correct angle ...so why is backlash a problem ..

all the best.markj

sidneyt
01-01-2009, 10:07 AM
One alternative would be to get a swivel angle plate like this:
http://www.phase2plus.com/details.asp?pr=SWIVEL_ANGLE_PLATES&id=206

I purchased one of these from Enco a couple of years ago on sale and they still carry them in their catalog. Mine is nicely made. The T-slots are accurately machined and it swivels smoothly through 90*.

aboard_epsilon
01-01-2009, 10:38 AM
this is mine bought off ebay for 30

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/setup.jpg

full 180 degrees of travel ..

all the best.mark

lazlo
01-01-2009, 11:03 AM
I was just lucky that Robert (lazlo) and others posted experiences preceded my purchase. Based on their feedback, I bought a non-screw version and I like it very well.

That's right, rub it in Russ :)

Seriously, my two options to fix the problem are to just remove the worm drive altogether, in which case I end up with the plain version for $50 more than I should have paid, or re-work the worm drive so it doesn't fall.

The latter is a Hell of a repair. From playing around with it, about 1/3 of the slop is from the crappy pillow blocks. Assuming the worm shaft and the screw spacing is standard (that's a big assumption), that part would be an easy fix.

The hard part is that the worm is crudely turned, so they cut the worm wheel into the base with a gi-normous manufacturing clearance. Reminds me a lot of the quill feed on my Mill Drill :) The only way I can see to fix that would be to braze the worm wheel in, re-hob it for a normal fit, and buy or make a new worm wheel.

If I consider my time at minimum wage, I can probably buy a Suburban tilting angle table for that investment of time :D

lazlo
01-01-2009, 11:06 AM
this is mine bought off ebay for 30

full 180 degrees of travel ..

I wish I would have gotten one of those Epsilon. It has much wider swing, so it can function as an angle block as well.

The plain tilting angle tables we're talking about go +- 45. The worm drive tilting angle tables go +45 - 15 (you lose 30 of travel on one side from the worm drive mechanism).

jkilroy
01-01-2009, 11:58 AM
I purchased the one with the screw, the screw sucked, I just took the screw off, it bolts to the bottom of the table. Works just like the "manual" one now. Too bad I spent the extra cash, live and learn.

dp
01-01-2009, 03:18 PM
Before I bought my table I handled a few that have the cranks and found them to bind and to have very rough action. Like a hand-crank coffee grinder. There was slop in the worm and it was pretty obvious the gear quality was low priority.

I still need to do a bit of lapping with the one I ended up with to free up some binding but it has been working out well. It definitely does not creep when locking down the tilt table which was a concern.

oldtiffie
01-01-2009, 08:01 PM
I must have been lucky as the worm and wheel were not bad at all. They were "slack" but of pretty good quality for the job they have to do.

The real "weak" points are:

1. the size of the screws holding the bearing blocks for the worm. They will "do the job" but they need to be considered if heavy loads at high tilts are used;

2. the tilt clamps as they are a friction clamp; and

3. there is only one pair of "feet" for clamping to the table (similar to most vises), but it is difficult to clamp to the tilting table by other means.

But, as said, given their limitations they are pretty good.

Also as said, when I got the 5 x 7 the errors were considerable, but the male and female rotating/part-cylinder parts were really good. That made re-machining a lot easier when I did it.

I haven't had a good look at the 10 x 7 yet but I plan to re-machine it anyway. The worm and wheel are quite good - much better than the 5 x 7.

The worm and wheel and the tilting cylinder were really good on both and they are what count as the rest can be recovered relatively easily.

I guess I was lucky as regards the quality of the worm, wheel and cylinders as it seems that others have not been.