View Full Version : Removing seized small grub screws

12-11-2011, 05:14 PM
Hi folks,

Got myself a new milling vice, a Vertex K5, and the thing is baked in solidified shipping grease which doesn't dissolve with WD40 or brake cleaner.

Got most of it removed but I can't get to the underside of the moveable jaw in order to clean it up.


There is a locking collar in front of the handle which takes the thrust when you wind the vice out. It's a standard steel collar with two grub screws securing it, which the manual describes as 'tapered pins' (I presume they are just grub screws with a point on the end, which fits into a dimple).

The problem is they take a 2.5mm hex key and they won't budge. Tried oil, heat, various types of hex keys, nothing. Luckily the heads on them haven't shredded but they definitely won't move.

Any tips on what to try here? Usually when I encounter this problem it's on a motorbike and I get the air gun out, but I'm worried about buggering the hexagon up.

Should I just drill em out?


12-11-2011, 06:44 PM
Did you try shocking them? I have heated ones like it up to just less than the point of losing any temper and with the hex key in give it a shot of WD40.

12-11-2011, 06:51 PM
"Shocking them":

I would take a small, flat-ended punch that just fits in the socket of the screw and whack it a few times. Then, take the hex wrench and remove the screw.

12-11-2011, 06:52 PM
I needed to shim the end block on my mill vice and found that the screws are left-hand thread. ?????


12-11-2011, 07:28 PM
Use an old fashion impact driver, you know, the kind you whack with a hammer so that as it untwists the screw, it also drives the bit deeper into the head helping to prevent strip out.

12-11-2011, 07:34 PM
As the collar is taking the thrust from the moving jaw via the (lead)screw it is more likely than not that a tapered pin was used and not grub screws (due to the thrust). But as there are hex sockets it just might be that they are grub-screws.

As the "pins" have hex socket heads its quite likely that they will be very hard to drill.

I have the 4" version of that vice and its not bad. I cleaned it off with mineral turpentine and gasoline.

I didn't need to dismantle it as it worked well enough

12-11-2011, 08:55 PM
"mineral turpentine" Don'tcha love it? Do you know what turpentine is?

12-11-2011, 09:13 PM

Mineral turps:

Spirit of turpentine:

12-11-2011, 09:26 PM
Good examples of why not to believe in Wikipedia.
Turpentine is the sap of the pine tree. It is a very thick, sticky liquid. This was collected in the past by a process very similar to the collection of Maple sap for syrup. The bark was scarred and sheet metal guides delivered it to a can hung on the tree. This eventually resulted in the death of the tree after many years. It was distilled to "Gum Spirits of Turpentine". The other major product was pitch, a heavy resinous semisolid used to seal wooden vessels. Now the turpentine is a by product of paper manufacturing, extracted from the wood in the pulping process. It is now the source of many chemical products. The Spirits of turpentine is not such a common paint thinner these days but the fact remains that turpentine is a product of pine trees and has no "mineral" origin. What you are referring to is known in civilized countries as mineral spirits, and is roughly equivalent to the gasolines of of 80-90 years ago, before cracking and tetraethyl lead.

12-11-2011, 09:38 PM
Be that as it may, but the lable on that bottle in Wikipedia is the same as several in my shed/shop - "Mineral Turps":




maybe its different down here in OZ.

12-11-2011, 09:43 PM
So you just ignore what you don't agree with? I am from the Southeast US where turpentining (what the harvesting process is called) was VERY common. Turpentine is from Pine trees. Very simple.

12-11-2011, 09:51 PM
I'm not sure what the problem is. Things are called different names in different counties - Tiffie is from one of those.... As am I but living here forces adaption to the local names, mostly.

If he has a bottle labeld "mineral turpentine", then down-under it probably is a "non-tree" sourced product.

12-11-2011, 10:09 PM
If you want to cite Wikipedia, Here ya go:

From Wikipedia, the free encyclopedia
For other uses, see Turpentine (disambiguation) (http://en.wikipedia.org/wiki/Turpentine_%28disambiguation%29).
Turpentine (also called spirit of turpentine, oil of turpentine, and wood turpentine) is a fluid obtained by the distillation (http://en.wikipedia.org/wiki/Distillation) of resin (http://en.wikipedia.org/wiki/Resin) obtained from trees, mainly pine (http://en.wikipedia.org/wiki/Pine) trees. It is composed of terpenes (http://en.wikipedia.org/wiki/Terpene), mainly the monoterpenes alpha-pinene (http://en.wikipedia.org/wiki/Alpha-Pinene) and beta-pinene (http://en.wikipedia.org/wiki/Beta-Pinene). It is sometimes known as turps.[citation needed (http://en.wikipedia.org/wiki/Wikipedia:Citation_needed)]
The word turpentine derives (via French (http://en.wikipedia.org/wiki/French_language) and Latin (http://en.wikipedia.org/wiki/Latin)) from the Greek word τερεβινθίνη terebinthine, the name of a species of tree, the terebinth (http://en.wikipedia.org/wiki/Pistacia_terebinthus) tree, from whose sap the spirit was originally distilled (http://en.wikipedia.org/wiki/Distilled).[1] (http://en.wikipedia.org/wiki/Turpentine#cite_note-0)
Mineral turpentine (http://en.wikipedia.org/wiki/Mineral_turpentine) or other petroleum distillates are used to replace turpentine."

Considering how Wikipedia operates, maybe I should log in and change "mineral turpentine" to, oh, how about "bull****tatine". That is how accurate Wikapedia is. Anyone can post anything, accurate or not. Per the entry above, "mineral turpentine" is an imitation.

12-11-2011, 10:14 PM
Did he say it wasn't? All he said is that he cleaned it of with mineral turpentine, and has a bottle of it labeled as such. Follow his google links also... like this
one :http://www.recochem.com.au/files/downloads/Industrial_Mineral_Turpentine_PDS_Apr10.pdf

12-11-2011, 10:20 PM
For consistency, using Wikipedia, here is mineral turpentine (as I posted earlier) which is mineral based and has nothing to do with turpentine from trees (Note the label on the bottle):


And to see that there are no tricks there, here it is from Google - also as posted previously:


12-11-2011, 10:21 PM
So you just ignore what you don't agree with? I am from the Southeast US where turpentining (what the harvesting process is called) was VERY common. Turpentine is from Pine trees. Very simple.

Hey pal, OT is right. They sell mineral turpentine as a substitute for real turpentine. It's like Splenda or "I can't believe its not butter!". Here's the msds for it: http://msds.qsmart.net.au/MineralTurpentine.pdf

Yeah, it ain't turpentine from trees, but that doesn't mean it doesn't exist.

<edit> Come on, TDMidget ... did you wake up on the wrong side of the bed or something? What gives? It's a product name, for cryin' out loud. Do you complain about the maple syrups at Walmart that don't have any real maple syrup, too? OT says he used a product called mineral turpentine ... in the US we call it mineral spirits, but in the UK and, apparently, Oz they call it mineral turpentine. He didn't say it was the same thing as turpentine.

12-11-2011, 10:22 PM
Sigh,,,,,,,,,,,,,,Gotta be the full moon!!!!!!!!!!!!!!!!!!!!!!!!!!!!:rolleyes:

Don Young
12-11-2011, 10:33 PM
The grub screws might have been installed with some sort of chemical thread locker. If so, heat will help in removal. Also, heavy blows on a punch fitted into the bottom of the recess will often do the job. Be sure the collar is solidly supported so the shaft and bearings are not damaged.

12-11-2011, 10:35 PM
Loply - drilling them out may be tough but you may find that is your only option. Many of those grub screws from the East seem to be pretty crumby. I've found that even using an impact driver, I've broken the hex. Instead of rounding it, they just make a loud snap and it actually breaks the hex. Good quality grub screws don't do this, but I think it has something to do with the way cheaper ones are formed... anyone else run into this?

Of course, if you drill them out it won't be pretty... you'll probably bugger up the cast iron pretty quick as the drill tries to wander from the (presumably) hard screw.

By the way, they do make tapered pins that screw into place. They can be very difficult to remove as you are fighting the friction of the taper.

12-11-2011, 10:41 PM
If you intend to drill them out, use a left-hand drill. Often they will just unwind at some point

12-12-2011, 01:07 AM
Drill it out, re-tap it, put real set screw in it and your done.

12-12-2011, 04:02 AM
Sigh,,,,,,,,,,,,,,Gotta be the full moon!!!!!!!!!!!!!!!!!!!!!!!!!!!!:rolleyes:

or they've been drinking Meths ( Methylated Spirit ) :D

12-12-2011, 06:27 AM
Hi folks,

Thanks for the advice.

This collar only takes the thrust when winding the vice OUT, not IN, so I don't think it needs to be strongly held in place... I can't see that it would be designed to allow you to clamp something by winding the jaw out?

In any case I think I will resort to more heat tonight and try again, if that fails I will drill it.

Unfortunately I don't own an impact wrench that you whack with a hammer!

The reason I wish to remove it is because I found quite a bit of very hard (solidifed) grease in places such as underneath the jaw plates and underneath the gib strips. This obviously was impairing performance and makes me think there's probably some underneath the jaw too, meaning it's sitting on solidifed grease rather than on the vice bed, probably leading to jaw lift and other inaccuracies.

12-12-2011, 09:50 AM
In any case, why didn't you buy a Kurt? Or a chink copy?

12-12-2011, 10:10 AM
Availability, pretty much.

I'm in the UK.

12-12-2011, 12:21 PM
Just cut the collar off, and make a new one. No sense in destroying tools (or wasting mineral turpentine!) on something so easy to reproduce.

12-12-2011, 01:20 PM
WD40 is not a penetrant.
Gently heat up the area and us kero, or mineral spirits thinned with acetone.
WD40 is for spraying on wet ignition wires.

12-12-2011, 03:45 PM
or they've been drinking Meths ( Methylated Spirit ) :D

"Denatured Alcohol" in the US

12-14-2011, 11:02 AM
Hi folks,

Just to let you know what the outcome was - I ended up grinding the thing off.

Tried all the tips from this thread including numerous different applications of heat, tried hammering in an oversized torx bit and turning that. In the end after the second broken key and second broken drill I gave up and grabbed the angle grinder.

Gotta hand it to the Chinese, for all the stupidity of these buggers being seized on a brand new product, they sure found some hard metal to make them from.



As you can see I made a bit of a mess of the shaft, but I will fill this and repair it on the lathe.

Was it worth it? I think so, the underside of the bed was only making contact on two tiny points as it has been finished real badly, you can see a bright line near the edge where the casting is rough. It looks like it was faced on a miller at too fast a speed and perhaps with a blunt spot on the tool.

In addition I was able to measure the thickness of the part of the bed that the moveable jaw gib strips act on. As I suspected it was variable - it got 4 thou thicker towards the fixed jaw, which explained why the handle got harder to crank as the jaw moved in. I will scrape or lap that out.

And lastly it was evident upon stripping that the gibs were fouling on the paintwork on the body of the vice, can't tell whether this was stopping the gibs from pulling flush when adjusting or whether it just added friction, but I'll be glad to sort it.

The whole thing needs a bit of TLC then it'll be good as gold. About what I expect from cheap(ish) Chinese products.

12-14-2011, 02:33 PM
Ya gotta do what ya gotta do. Looks good to me. The shaft will be covered anyway. Make a new collar and GET TO WORK! :D

Gotta run now. Going to fill up the truck with some mineral diesel. :cool: