Part 10- Dove Tail Slide

 UNIVERSAL TOOL AND CUTTER GRINDER

 Message from the author: This is a continuous article intended to be updated by myself as new and better information is compiled. Any comments or additions for my article, please contact This email address is being protected from spambots. You need JavaScript enabled to view it.. If your information can be of help to these articles, I will include the information and your name. If you do not want your information or name included let me know. (James Long)

Purpose:

Dovetails and V-Ways provide a method of allowing two parts to move or slide in a straight line with minimum resistance as well as minimum side to side and up and down wobble or, as we in our trade  “no excess play”.

 

This section will be referenced in other pages of my articles as it pertains to many of the parts in the Index Head.

In the course of this article, I will discuss all the V-Ways to include the Cross Slide Drum, X-Y Tool Holder and all tooling intended to attach to the X-Y Table.

 

Cross Slide Drum and X-Y Tool Holder:

Measuring Dovetails:

Male and Female Dovetails must be measured in the each end

and the middle (three points).

 

 

I used .250” (1/4”) precision ground dowel pins for measuring.

The parts should be clean and there should be no rocking motion

with the pins in place indicating an imperfection in the Dovetail

machining. The measuring pins should touch the approximate

middle of the 45° side the flat bottom V-Way (see diagram # 002).

 

 

 

45° Dovetail Cutter

 

 

Start with the Cross Slide Drum Female V-Way:

 

We start with CSD because the X-Y Tool Holder always remains in the CSD.

Check the Female V-Way of the CSD. There are two sides of the

Female V-Way, Primary and Adjustable. The Adjustable side is not as

critical because the Adjustable Gib will line up with the Primary Side

 

Check that the Primary Side has a good straight cut.

There is no need to worry about the V-Way being set to perfectly true to the

Main Axle. This will be set when we calibrate the machine.

Tthe V-Way must be parallel with base pallet of the Cross Slide Drum.

 

Male Dovetail of the X-Y Tool Holder:

 

The Male Dovetail can be easily chucked in the mill vice.

Assuming you vice is square in the vice and the Mill Table, dial in the top surface of the Dovetail.

Measure and true the Dovetail as needed. The width must be consistent for the part to move

smoothly in the V-Way.

 

 

Female X-Y V-Way:

Once the Male Dovetail is completed, turn the part over, chuck it in the vice.

If your vice has been dialed in properly the Male and Female Dovetails will be 90° to each other.

 

***Note that the Male Dovetail is chucked to insure 90°

accuracy for the Top Female V-Way and only machine

the Primary side.

 

 

An excellent article on making Dovetails and Gibs@

https://johnfsworkshop.org/milling-machine-how-to-make/milling-machine-how-to-make-dovetails-links/making-dovetails-the-first-type-parallel-gib/

 

Lapping, the final frontier:

 

 (From Wikipedia)

 Lapping is a machining process, in which two surfaces are rubbed together

with an abrasive between them, by hand movement or using a machine.

Lapping involves rubbing a brittle material such as iron with an

abrasive such as aluminum oxide, jeweler's rouge, optician's rouge,

emery, silicon carbide, diamond, etc., between them.  This produces

microscopic fractures as the abrasive rolls about between the two

surfaces and removes material from both.

 

 

I used Glover 500 Grit, Silicon Carbide, Grease Mix.  Part # 39536

(very fine-get the smallest size container you can find, it lasts forever).

Other finer grit compounds I have read about are

Mothers Mag & Aluminum Polish and Simichrome.

 

An excellent Youtube on lapping can be seen @

https://www.youtube.com/watch?v=D6GIqhXcTh8

 

Put compound on the Top Slide and the Cross Slide Drum Dovetail

contact areas, assemble, lightly tighten the gib screws until there

is a slight resistance.  Slide back and forth the full length of the V-Way.

 

As the high spots wear down, you will have to keep tightening the gib screws.

You can feel the V-Ways get easier to move.  Remove the compound and

check the contact surfaces at regular intervals.  Completely remove and

d-grease the parts each time you check the progress.  This is most important

on the the last lap as the compound will continue to erode the part.

 

You can pretty much tell how you are doing by the look of the clean contact surfaces.

Only lap as much as necessary. The ultimate goal is to have 80% contact on both

V-Way surfaces. 100% contact is not necessary.

 

The Gibs:

I don’t think I need to say much about these as they are basically a flat plate with

indents for the Gib Adjustment Screws.

 

Before I purchased my grinder I read a lot of complaints about the Tool Holder

side of the Top Slide having a problem with the Gib coming out every time the

tool was changed. And this did turn out to be a problem for me.

I solved this problem by making the Gib longer and wider and milling out the

bottom center to create legs on each side of the Gib to prevent it from falling out.

 


Here is a good article on lapping on the working side of the Gib if you do not

have a surface grinder. The inside, where the adjustment screws touch does

not have to be smooth.

 

Lapping the Gib:

http://www.mini-lathe.com/Lapping/Lapping.htm

 

The Tool V-Ways:

  • Rectangular Tool Holder
  • Collet Tool Holder
  • End Mill Sharpener

 

All these tools and any other Tool Holders you will make must have

the same size Male Dovetail to be able to quickly change them into the

Top Slide.

 

 

 

Tool Holder Dovetails:

 

Measure all the Dovetails and mark the measurements with a Sharpie (see photo # 006).

 

Determine the smallest diameter Dovetail and match the other Tool Holders to that dimension.

 

 

 

 

Before any machining of the Dovetails do a complete check for parallelness in all directions.

Be aware that if any of the Dovetails are too far off of square and in need a lot of correction,you should to fix that first. If you do not spot this before machining, you may have to go back and redo all the Dovetails.

 

The last step is to lap in all the V-Ways until they work smoothly

(see Lapping, the final frontier)

 

 

 

 

I AM STILL WORKING ON THIS ARTICLE

 

 

 

Please contact me for corrections, additions or questions…..James Long

This email address is being protected from spambots. You need JavaScript enabled to view it.

 

Terminology of parts Disclaimer:

Several names of the parts have been taken from the Deckel Catalog; to insure you the reader, will always know what part I am referring to. I have applied the identification of parts from other machines, catalogs and some I created for a clear description of the parts function, (eg. Top Slide Tool Holder).