wedge locks and slipping carriage

farley · Post by **farley** » Sun Nov 14, 2010 5:01 pm

when in drill press mode, my carriage slips.

so I read all the post on what to do.

I am going to put it back together but wanted to share a pix of the wedge locks because I don't know where "wear" would be.

I am assuming that the slanted part of the wedges are what grip the way tubes.

My wedges seem to be in good shape, but the shinny parts on both wedges are just that "shinny" also there is a very small dip on the shnny parts. Is that wear?

In the meantime I am going to put it back together and reverse the wedges.

just don't know what good wedges look like.

OK--Things seem better--maybe reversing the wedges did it. If someone tells me that is where wear is on the wedges appear,I'll order some next SS order

TIA

dusty · Post by **dusty** » Sun Nov 14, 2010 5:20 pm

farley, those don't look bad. I have seen wedges that look much worse and still work. In the picture, the sloping part on the right hand side appears shiny but that may be just glare in the photo.

I know you have extra tubes (partials). If the carriage has been removed, you could mount it on those extra tubes to see if they lock there.

If you don't get it fixed, bring your carriage and carriage lock mechanism and we can work on it here. I just remembered, you have a mini and a Mark V. You may not need that access but I am still here.

JPG · Post by **JPG** » Mon Nov 15, 2010 3:09 am

Not sure how you 'reversed' them since they are a left/right threaded pair. The wear is apparent, but as Dusty said, they do not look all that bad. You can file the wear notch back down flat.

More than likely they are not installed on the threaded shaft correctly. The easiest way to position them is to run them all the way towards the center, then while preventing them from rotating, turn the shaft until they are near their normal spacing(the end with the wing nut will be almost bottomed out).

Then install the headstock onto the tubes. They should lock on BOTH tubes after a few turns of the wingnut.

I just took a second look at your wedges. I believe they are 510/20 version.

What I posted above applies to the older '500' genre. I do not have enough history with the 510/20 version to be helpful, but there has to be away to adjust them!

farley · Post by **farley** » Mon Nov 15, 2010 10:04 am

by reverse, I mean, the right one has now become the left one and the left the right. they are not threaded, just slide onto the square shaft. These are for the carriage of a 510.

keakap · Post by **keakap** » Sun Nov 21, 2010 12:31 pm

farley wrote:when in drill press mode, my carriage slips.
...
TIA

The adjustment is, I believe, a big old nut on the end of the clamping arm. Test in 1/8 revolution increments.

A common "fix", though, is to use 4x4 blocks (or equivalent) between the carriage and base. If you most often position the carriage in drill press mode at about the same vertical, you'll probably get by with one 4x4.
(The basically same thing can be used under the table itself for extra heavy duty drilling where the table may flex a bit.)

Same idea holds true for horizontal boring mode, but it's easier: just run the carriage all the way to the right, using the base as a 'stop'.

Lodgepole · Post by **Lodgepole** » Mon Nov 29, 2010 9:30 am

Farley, I am apparently having the same problem as you. How did your switching the wedge locks work for you?

farley · Post by **farley** » Mon Nov 29, 2010 9:53 am

Little better, but than the other day small slippage.

so when I was done, I tighten the nut a little more, but since haven't used it in DP mode.

dusty · Post by **dusty** » Mon Nov 29, 2010 9:57 am

A pair of new wedge locks is not that expensive. If I was faced with this problem, I would order a "new" set of wedges; but only after cleaning the tubes with mineral spirits and rewaxing and making certain that the faces of the wedges were smooth.

Locking the headstock and carriage is a function of friction. Anything that prevents the development of friction impairs the locking mechanism.

I would also clean and lubricate the threaded rod (headstock lock) to make certain it is not binding and preventing the tactile feel of locking.

Just don't crank down on the lock - that can easily become "bad news" for the tubes.

After oiling - Does everyone wipe down the tubes to remove the oil that was slung from the oil points (within the headstock).

Lodgepole · Post by **Lodgepole** » Mon Dec 06, 2010 8:56 am

Dusty,

I cleaned up the tubes and rewaxed them. The carriage now locks perfectly!

Thanks for the tip.