Headstock Quill lever Allen Screw?

baddlad · Post by **baddlad** » Fri May 01, 2009 7:42 pm

ok yeah that was like greek to me.

SDSSmith · Post by **SDSSmith** » Fri May 01, 2009 7:48 pm

baddlad wrote:OK I am about to give up on removing the allen screw in the headstock that holds the quill lever mechanism.

Just to be sure.....which set screw are you trying to remove. The one on top of the headstock that retains the quill or the one on the side that tightens against the quill return spring housing?

JPG · Post by **JPG** » Fri May 01, 2009 7:50 pm

baddlad wrote:ok yeah that was like greek to me.

How could that be? There are NO strange characters(other than the author:D ).

dusty · Post by **dusty** » Fri May 01, 2009 8:21 pm

mickyd wrote:If all else fails, you can easily drill it out, retap oversize and use a helicoil to bring it back to the same set screw diameter OR tap oversize and use what's called a half dog point set screw OR just drill and tap in a slightly different location.

I believe the allen that is in there is suppose to be a half dog.

dusty · Post by **dusty** » Fri May 01, 2009 8:34 pm

JPG40504 wrote:OK Mr Bolt expert:D WHAT is a half dog point set screw???????

BTW You might mention the Heli-coil solution requires special(expensive) tap and maybe an insertion tool(also expensive). Kinda extreme for ONE set screw, BUT it WOULD be closer to ORIGINAL!!!!!:D

http://www.mutualscrew.com/index.cfm?killnav=1

http://www.mutualscrew.com/department/half-dog-point-socket-set-screws-13083.cfm?refdep=Half%20Dog%20Point%20Socket%20Set%20Screws

charlese · Post by **charlese** » Fri May 01, 2009 8:46 pm

Are all of the set screws we have on the MarkV half dogs? Or is it just the ones with a circle seat? I ask these questions as I had never heard of half dogs before.

JPG · Post by **JPG** » Fri May 01, 2009 8:55 pm

charlese wrote:Are all of the set screws we have on the MarkV half dogs? Or is it just the ones with a circle seat? I ask these questions as I had never heard of half dogs before.

The set screws used to attach tools to the quill shaft are usually domed end. The ones holding it together(way tubes in end pieces) are cup. I have just recently learned the extended set screw is a dog/half dog. The set screws holding the spt tubes are cup(they usually leave a ring cut into the shaft being tightened to).
http://en.wikipedia.org/wiki/Set_screw

dusty · Post by **dusty** » Fri May 01, 2009 9:07 pm

charlese wrote:Are all of the set screws we have on the MarkV half dogs? Or is it just the ones with a circle seat? I ask these questions as I had never heard of half dogs before.

The only half dog that I know of is the one on the top of the headstock (for the quill). However, the help kit that I received had that one and another (longer) that I have not found a home for.

Another bit on info related to set screws:

http://icrank.com/cgi-bin/pageman/pageout.cgi?path=/data/screw/setscrew/setscrew_source.htm&t=2

I have heard that some of the Shopsmith set screws are made of a softer material. I have yet to find a source for "softer" set screws.

charlese · Post by **charlese** » Fri May 01, 2009 9:14 pm

O.K. Maybe I'm getting it. By "Extended tip" do they refer to only cup tips, or do they also refer to flat and rounded tips?

This from Wickipedia -
"...Set screws appear with a variety of tip types. The different shaped tips have different properties that engineers can utilize. If an engineer were to use a detent to ensurce proper nesting of the screw, they might choose to use a cone point type of screw. One might might often need to use a flat point when the screw must press perfectly flat against a surface. The most common type is the cup point. This type works well because the surface is rounded so that a small surface area is in contact, but it does not have extremely high stress at one point like that of a cone point. Durability studies show that the cup point offers superior resistance to wear while maintaining a strong grip. [1]

Common points include the following:

Flat Point
Domed Point
Cone Point
Cup Point
Knurled Cup Point
Extended Point (Pilot Point, Dog Point) "...

dusty · Post by **dusty** » Fri May 01, 2009 9:23 pm

charlese wrote:O.K. Maybe I'm getting it. By "Extended tip" do they refer to only cup tips, or do they also refer to flat and rounded tips?

This from Wickipedia -
"...Set screws appear with a variety of tip types. The different shaped tips have different properties that engineers can utilize. If an engineer were to use a detent to ensurce proper nesting of the screw, they might choose to use a cone point type of screw. One might might often need to use a flat point when the screw must press perfectly flat against a surface. The most common type is the cup point. This type works well because the surface is rounded so that a small surface area is in contact, but it does not have extremely high stress at one point like that of a cone point. Durability studies show that the cup point offers superior resistance to wear while maintaining a strong grip. [1]

Common points include the following:

Flat Point
Domed Point
Cone Point
Cup Point
Knurled Cup Point
Extended Point (Pilot Point, Dog Point) "...

Sorry, charlese. I'm just a parts guy with a tool box. You are now asking questions that must be deferred to engineering.