Part 10- Dove Tail Slide
UNIVERSAL TOOL AND CUTTER GRINDER
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:
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@
Lapping, the final frontier:
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 @
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.
Lapping the Gib:
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
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
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).