Need help identifying this toolpost

[fratskop]

Hi all,
I’ve tried this on another forum already with no luck but here goes: so i recently bought a colchester mascot 1600 for a reasonable price given the state of it, problem is that it came with no tool holders i have no idea what kind of post it is thats sitting on there now here’s a picture:
I have only ever worked with the dickson type toolposts so this is very unfamiliar to me. Some measurments: the total width of the block is 106 by 106 mm, the height is 80 mm and the Outer end of the dovetail is 73mm ( metric lathe, so sorry for no values in inches)
I have searched the web far and wide for something that resembles it, but to no avail. Hoping to have Some luck here since i just wanna buy Some holders for this or else i gotta buy a new post.

 

[NortonDommi]

Or make some toolholders. How close is it to an AXA 250-400 or one of their other sizes?

 

[fratskop]

Or make some toolholders. How close is it to an AXA 250-400 or one of their other sizes?

I guess it comes closest to a CA at 4 inches (or 101.6mm) but i cant find any dimensions of the dovetail itself, only Total width and height. I could try to make Some myself but i dont really trust myself that much with stuff like that since ive never done it before

 

[WCraig]

For the quick change toolholders that Shars sells, they have a diagram showing the key measurements of the dovetail attachment:

Eg:

For a CXA toolholder, the dimensions are:
H: 0.555"
L1: 2.202"
L2: 1.681"

Get the same series of measurements from your toolholder and that should have determine what you've got.

See: https://www.shars.com/products/tool...ders/turning-and-facing-holder-1-type-301-cxa

Offhand, it does not appear to me that the angle of your dovetails is 60 degrees, however.

Craig

 

[T Bredehoft]

Offhand, it does not appear to me that the angle of your dovetails is 60 degrees, however.

With two parallel surfaces on each corner it almost has to be 45º

 

[fratskop]

For the quick change toolholders that Shars sells, they have a diagram showing the key measurements of the dovetail attachment:

Eg:

For a CXA toolholder, the dimensions are:
H: 0.555"
L1: 2.202"
L2: 1.681"

Get the same series of measurements from your toolholder and that should have determine what you've got.

See: https://www.shars.com/products/tool...ders/turning-and-facing-holder-1-type-301-cxa

Offhand, it does not appear to me that the angle of your dovetails is 60 degrees, however.

Craig

Here is a more up close image, looks to me to be somewhere around 60 degrees, unfortunately i dont have a protractor at home (yet) so ill just have to take Some more measurments and calculate it

 

[Bob Korves]

Pay attention to what Tom posted, they are 45 degrees or very close to it. Edit: The angles look different because you are not looking straight down on the part. Check the slots for parallel sides with a caliper, and don't let the internal corner radii mess up the test. If those slot walls are parallel, then the dovetail angles must be 45 degrees.

 

[fratskop]

If those slot walls are parallel, then the dovetail angles must be 45 degrees.

Makes sense, problem is i am now even more clueless as to what type of holder this is. ive never encountered a 45 degree dovetail before and cant find any information about something similar to this. guiss i'll have a go at making some myself.

side note: i also find it very weird that the clamping pistons are only on one side and not central, what makes even less sense to me is that they are on the 'back' side of the dovetail because to me it seems logical to put them on the front side so the clamping force is closest to where the cutting forces will take place

 

[Latinrascalrg1]

Thats a 45°ish angle as measured by overlaying a protractor over the overhead picture. If that picture is not perfectly taken directly above the tool post will change this of course.

Im guessing its a home made tool post.

 

[fratskop]

Thats a 45°ish angle as measured by overlaying a protractor over the overhead picture. If that picture is not perfectly taken directly above the tool post will change this of course.

Im guessing its a home made tool post.

tried this and it is indeed a 45° angle. you could be right about it being home made since i have never encountered a post like this one and cant find anything similar on the web. so, if i were to make a holder myself, what material could you reccommend? (i guess something that could be hardened seems logical)