Chipping of blade from buffer.

I have been doing some restoration work with buffers recently. My tool of choice is the HF 8" buffer; which I know is a lil fast, but I found the link to the Grizzly buffer too late!
Question is that I have had some issues with minor chipping along the edge of some blades and even a toe chipped. A running theme seems to be that blades that are fully hollow or thin grinds are much more likely to chip? Is the issue technique, grind, tool used, or a combination of it all? I have had some success with thin grinds though, but always great outcome for half hollow and thicker. Thanks in advance for your replies.


Andrew

4 inch wheels
Light pressure
and above all else

DO NOT Run the wheel into the edge, if you are buffing spine to edge, you have to make SURE that the edge is pointing straight down and that the buffing wheel is not impacting into it, rather than just gliding over it.. Someplace on here I have pics of this and it makes way more sense seeing it rather than explaining it...


Keep in mind that a 8 inch buffer running at 3450 is the same SFPM as a 4 inch Buffer running at 1725 :hmmm: the 4 inch wheel also lets you get into the hollow better


here

http://straightrazorpalace.com/works...tml#post623194

Thank you very much that makes a lot of sense with the pictures. I was applying some torque and touching the edge to the buffing wheel. I am currently running six inch wheels since that's was the smallest I could find locally, but will order the four inch wheels ASAP. Do you always run the razors perpendicular to the buffer? There were times I would slightly angle them for comfort/getting into areas better; is this okay? Thanks again.

Reading the thread I linked will show several ways the people use the buffers...

I personally almost always follow the same direction as the original grinder did, so for most razors that is Spine to Edge, Yes I know that that isn't technically correct but Edge to Spine doesn't work too well on a buffer :p

I try and follow the same direction, going across grain I feel makes the razor look funny but that is just me...

Quote:

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Originally Posted by gssixgun

Keep in mind that a 8 inch buffer running at 3450 is the same SFPM as a 4 inch Buffer running at 1725 :hmmm: the 4 inch wheel also lets you get into the hollow better

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I think you got it mixed up 8 inch buffer running at 1725 is the same SFPM as a 4 inch Buffer running at 3450

I continue with the grind as well, but use a dremel which I need to be *very* careful with... both with buffer wheel speed, direction, proximity to the edge. Blue magic, flitz, white paste all seem to work well.

Next to safety face shield, the most important thing for me to remember is not to lax in my attention to any of the things I mentioned above. The moment I do, giiiingt! burrrrvv! scratched tang, shaved buffing wheel.

Quote:

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Originally Posted by Bruno

I think you got it mixed up 8 inch buffer running at 1725 is the same SFPM as a 4 inch Buffer running at 3450

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:brunoisright

Swmbo won't be happy to see another shipment of buffing wheels, but it's a necessity evil right? Wet shaving seems to about seeing how close one can get across the board whether it's a shave or your girl's last nerve.

4 in wheels as said, Castwells for good quality wheels and use plenty of water when the blade First begins to heat up. I use a cut off water bottle near the buffer cause you will knock it over.

I run 2 wheel of the same grit so one is drying, while the other is in use. Also mark the rotation of the wheel when first used and mark the grit of greaseless in magic marker high enough on the wheel to be read over the stabilizing washers.

Let the wheel do the work, pressure just heats the razor and prematurely wears off the compound. Rake your wheel and trim with a sharp scissor before loading the first time. AND WEAR A MASK.

Castells has very good buffing primer as does Metal polish for aluminum, silver, brass, chrome, stainless steel, copper and bronze from English Custom Polishing..

And here is the link to The Now & Zen of Custom Metal Polishing from English Custom Polishing in PDF, a good read and a wheel size/ speed chart.

Yeah I learned the hard way about prepping my wheels with rake and scissor. The wheel was the only thing not covered in compound!

Thanks again everyone for all the tips. I ran a new batch of restores through the buffers with no issues. Thank god since my first stubby was included.

As far as I know, regarding Surface Feet Per Minute (aka sfpm, sf/m, sfm) the rough rule of thumb is that the sfpm = 1/4 diameter of the wheel x RPM of the spindle, thus an 8" wheel on a machine rotating at 3,600 rpm at the spindle will be 7,200 or thereabouts ((8/4)x3600). So a 6" wheel would have a sfpm of 5,400 and a 4" wheel 3,600.

Obviously this is just a rough and ready guide, as the outer perimeter of the 4" wheel must spin somewhat faster than the spindle, which is an altogether thinner diameter in cross-section. It works well enough, though.

I may be totally wrong of course, but I have used this rule of thumb for many years with no mishaps - no overheating, no ruined tempers, no heat discolourations, no chipping of the blade, etc, etc, etc.

In other words, on the same spindle rotating at the same speed, a larger wheel spins faster at its surface edge than a smaller wheel - a handy way of controlling sfpm buffer speed. I use a stepped pulley system to enhance the effect, using larger/smaller pulleys on the motor connected to smaller/larger pulleys on the buffing arbour.

Which leads to a little puzzle, the closer we get to dead centre of the spindle the slower the sfpm, so one would expect to find a zero speed at the exact centre of rotation. But - this is not the case, as even an elemental particle spins around its own nucleus...

In the old days (this gizmo has patents from 1901 - 1904 on it, pic courtesy of Practical Machinist) you had a hand-held device (a 'cut-meter') to tell you the spindle speed:

Attachment 165271

Oh for the simple life... :)

Regards,
Neil

That's a really cool looking tool.