If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
I was just checking out 10KPete's pin spanner and I thought, "It's just like mine!" And then I saw he has put a joggle in the arms. Dang! Why didn't I think of that?
Regards,
Preso
I was just checking out 10KPete's pin spanner and I thought, "It's just like mine!" And then I saw he has put a joggle in the arms. Dang! Why didn't I think of that?
Regards,
Preso
'Cause ya didn't hafta reach down in a recess to get the lock nut!!
You should have your spanner marked or engraved with maker and date for future owners.
'Cause ya didn't hafta reach down in a recess to get the lock nut!!
You should have your spanner marked or engraved with maker and date for future owners.
Pete
Well 10KPete, I have accepted your challenge and filmed the result!
I purchased a diamond drag engraving tool a few years ago with the goal of being able to accurately engrave graduations on cylindrical surfaces like indexing dials and the like. Mine was fairly cheap however if you want to go all upmarket you can buy a Tormach drag engraver. I got mine from Ebay and it looks like a home shop job or maybe a limited run but it works beautifully. I cannot find the Ebay listing for the one that I purchased but the link to the Tormach unit is here http://www.ebay.com.au/itm/CNC-spring-loaded-Diamond-drag-engraver-tool-bit-mill-router-mach3/253147391928?hash=item3af0c2a7b8:g:UIgAAMXQVhFR9Ty x
I don't like the thought of driving delicate rotary engraving tools into steel on a CNC mill because the tolerance on the Z travel is very small and if you get it wrong you'll smash the cutter every time. The beauty of the drag engraver is that the plunger carrying the diamond point is spring loaded and will exert just the right pressure to engrave to a given depth with plenty of tolerance (up to 2 or 3 millimetres.)
Cheers,
Preso
Preso, I'm familiar with drag cutters as used in the vinyl sign shops. But I've never heard of one for that use!!
Very nice. Now you've created an heirloom..
We purchased a spring loaded rotary engraver from L2 to engrave stainless nameplates that are far from flat. We are very pleased with the results. We use CamBam single stroke fonts and the lettering is very sharp.
The short answer is that it does not.
Preso suggested that the tip goes down to -1 mm, but I would have to disagree. The spindle goes down to -1 mm, but what that is doing is compressing the stiff spring inside the shaft. The drag action then ploughs the diamond tip through the metal to a depth set by the combination of the force, the shape of the diamond tip, and the the hardness of the steel.
If the surface is not flat (constant Z), the spring compression will vary a bit, and so the depth of the engraving will also vary a bit. One would not normally inspect the width of the engraved lines that closely, so it does not matter.
The other way of doing this is to have a floating face which actually rubs against the stock surface being engraved, and the diamond tip (or carbide tip) sticks out a short distance - say 0.2 mm. After a couple of passes the floating face will be rubbing on the surface of the stock and the diamond will be in a groove of known depth.
In practice the difference in the results is rarely significant.
Cheers
Roger
PS: There is both L2 and 2L in the engraving business. Confusion reigns.
holesaw arbor for my mill. 25mm shank, 5/8 18 thread for holesaws. goes to MT4 collet and carier in spindle.for quick&dirty holes in plates before boring and tube notching
Last edited by Kolacek; 05-17-2018, 03:32 PM.
Reason: pictures edit
on most of arbors you do not have perfect timing between thread and lugs and there is allways gap between arbor and back side of holesaw. then the holesaw is "wigling" on arbor and all the axial load goes through threads. so i made threads sliding inside bore, with keyway and "dogpoint" setscrew antirotation feature.
and M6 hex capscrew is pulling holesaw tightly to arbor. So all axial load is supported by back of the cuter and pins takes all the torque.
edit: setscrew wil be flush with the surface, this one i had on hand.
Last edited by Kolacek; 12-10-2017, 02:37 PM.
Reason: .
Comment