Crystalmaster 8 flat lap machine

I’m considering the purchase of a Crystalmaster 8 flat lap machine
and would appreciate any advice or thoughts from those that have had
experience with this piece of equipment or other flat lap machines. I
would use this machine for inlay but also for cabbing, and would
especially appreciate any thoughts concerning this equipment for
cabbing. I have had a couple of comments regarding this equipment as
hard to cab with. Currently, I use 8 inch diamond wheels but dislike
them for flattening the backs of cabs. All thoughts greatly

John Barton


I'm considering the purchase of a Crystalmaster 8 flat lap machine
and would appreciate any advice or thoughts from those that have
had experience with this piece of equipment or other flat lap

While I do not use the Crystalmaster, I use and old Sapphire
faceting machine for this purpose. My cabbing machine is a Covington
8" Combo unit. You are right in that it is a bugger to polish the
backs on a round wheel, you would think it would be easy.

I made a couple of changes to the sapphire so it would work better
for me. I put cork around the splash lip and I put a bar across the
top of the plate with cork attached to the face. The cork is for when
a stone slips, it may(has)chip, and second as the drag of the stone
is often more than my finger grip on a wet slick stone. The bar works
well for me to retain the stone. To start with I use a 300 diamond
plate and then to a 600 and 1200 and progress to 2500 wet ‘n’ dry, I
dampen the top of the plate to hold wet ‘n’ dry paper and then on top
I have a drip on. I did not have good results using the diamond
films, it was hard for me to hang on to, and the water trick on the
back did not seem to work as well, the film wanted to hydroplane. Not
knowing what your top plate will be, make sure you dry it off, mine
is aluminum and depending on the stone will cause pits if you don’t.
When this happens the only way to clean it and keep your plate flat
is to chuck it up in a lathe and go over the face lightly.

I have had a couple of comments regarding this equipment as hard to
cab with. 

I have not tried to cab with the sapphire, but would suspect it to
be a bugger unless you make a plate that has a foam top to contour
with. A hard surface for me just will not blend the surface well or
to my liking. I just see no way to get optically smooth curves from a
flat hard device.

Hope this helps, it has been my experience to date with cabbing.


P.S. Rotate the stone while on the lap, keeps it from slanting to
bad. At least you won’t notice it as much, there is nothing to be
done to actually keep it from curving a little when laid on a
straight edge, there will always be hydraulic pressure in the middle
you can not over come and I have found it useless to try.

Haven’t used the Crystalmaster, but I have used the All-U-Need for
around 10 years. I cut my teeth (pardon) on a flat lap. I have an
arbor with round diamond wheels, but dont use it much. How can you
get a flat surface on the thing? Also, on the flat lap I can get
right down to eye level with the wheel if I want to, which is hard
on the other machine. In any case, I do intarsia, so a flat lap is
the only option. The only thing a wheel is good for in my opinion is
removing material fast.

Hi…my Flatlap is an Ameritool. I have never used the one you are
mentioning, but wouldn’t hesitate to acquire it.

I do all of my channel inlay pieces (flat/to precisely match/fit) on
it. When I have all the pieces set in the bracelet/bead/pendant,
etc., I use the graduated grits to finish - doming/rounding,
polishing to the end. I also do cabbing, very easy - have been using
this type of machine for over 20 years when I started with the All
You Need, which is still working like charm. I do have the Raytech
standard Lapidary equipment, which I use as a teaching too, but my
students like the flatlap the best.


Thats funny todd, The only thing I use my “all u need” for is to get
the flat surfaces I use expandable drums to get nice arcs on the
stones I cut!

How can you get a flat surface on the thing? 

You get a flat surface with a round wheel by putting your material
against the wheel, holding it in the same place and turning the
material around in a 360 degree rotation.

I have not had a problem getting a flat polished surface. My Genie
has a place on the end where you can add a flat lap, where the
polishing wheel with leather would go. I found out about that after
years of making flat backs on cabs with the round wheels. Of course,
it is easier on small cabs than large ones easier with softer
materials than harder materials.

How do you get a dome on a flat lap? I do not have experience with
cabbing on flat laps, round diamond polishing wheels with some give
when pressure is applied sure make it easy to get a smooth polish
fast. I have done pieces for intarsia using a round wheel, and have
been able to get right angles on small pieces I need for them to fit
together tightly.

I think we can learn to adapt to any machine to get the results we
need. Sometimes desire and perserverence with skill and patience
allows us to overcome rules and limitations.

Richard Hart

John I was just looking at new catalog that came out from Arrow Head
Lapidary Supply and saw the 8" you are referring to. Their sale
price is $521.00 and you need to buy the companion kit for
$210.00…pretty pricey- $730.00.

Why don’t you check out Ameritool - quite comparable in performance
and more reasonable? The whole 8" with the accessories is only
$579.00 complete. Ameritool is in Redding, CA telephone: 530-223-
They are great to do business with.

I use a little footfeed attached to the electric cord…I don’t
shut off the unit and when I want to use the machine, I just step on
the pedal and have power - what a saving instead of moving the hand
down each time to turn the knob. I also use warm water in the little
reservoir - saves the fingers from being in cold water.

Both of them have a small cup to collect the water and slurry. I use
one of the hospital plastic tubs and don’t have to empty so often.
Don’t reuse the water in the cup, nor put the slurry in your drains.
It would plug them up pretty fast…most of the slurry I put on the
roses. Controversial - I don’t think I am grinding anything to
pollute the soil! HAHA

Have a great day.
Rose Marie Christison

I guess I’m biased since I started on a flat lap. When making
intarsia, even on a flat lap, it can be hard to get the perfect
flatness required to get NO visible seam between the different parts.
That is one way to tell the real quality of the piece IMHO. To do
this while also trying to get a 90 degree edge, AND just the right
width of the piece (what you see from the front), all at the same
time can be tricky, even on a flat lap. I dont see how it would be
possible on a round one. I guess the technique Richard mentioned of
rotating the piece against the round wheel would be good enough for
flattening the back of a cab for setting, though it will not be
perfectly flat, as I require in my work.You can also put soft pads
under the sanding disks on a flat lap, and get comparable results to
wheels. I suppose sets of round wheels might be faster in a high
volume production environment, since you can quickly switch sandin
from one wheel to the next.

Todd Welti