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View Full Version : Building a cnc dust boot / dust skirt extractor



craynerd
12-03-2016, 10:17 PM
The Isel machine I recently overhauled is running really great and I recently built a dust boot for it. I've been using it for a few weeks and I need to change the bristles but it is working well. Any advice or opinion would be welcome.


http://www.youtube.com/watch?v=jqDR3b1lLxg&


http://youtube.com/v/jqDR3b1lLxg&

JAZZCNC
13-03-2016, 11:32 AM
Nice job looks like works well. Regards the cutting I suspect your problem wasn't speed but DOC.? It looked quite shallow bigger chip would have removed the heat with the chip and stopped melting.

craynerd
13-03-2016, 12:09 PM
Nice job looks like works well. Regards the cutting I suspect your problem wasn't speed but DOC.? It looked quite shallow bigger chip would have removed the heat with the chip and stopped melting.

WOW!!! I've got the same issue with HDPE now but only using a 2mm cutter. It is melting a few mm above the tip of rage end mill, setting hard and then scratching the work piece! I keep setting shallower depth of cut... So you think I should go the opposite. Regarding cutter spindle speed, what should that be?

JAZZCNC
13-03-2016, 12:50 PM
Common mistake is to go shallow when the answer is often to go deeper. Also reduces tool wear because cutting too shallow is most common cause of excess tool wear.
However small cutters are slightly more difficult to deal with because of there tendancy to want to snap for no ryhm or reason.?

Rule of thumb for run of mill sizes ie 4mm up is DOC 50% diameter. Below 4mm then drop to 30% or lower for really tiny cutters.

Obvioulsy cutter type and coating ie Carbide Ti etc will be very differant to HSS so you'll need to adjust accordingly. Carbide tooling is more expensive but often worth the expense because you can cut deeper and faster and with less tool wear. It's not uncommon to cut 100-150% dia with carbide tooling in some materials.

So many factors come into play but don't be afraid to cut deeper you will get a shock just how deep you can cut with some tools and materials. It's worth sacrificing a few tools/materials to find the limit or best setup because if doing lots of the same material it will save you time and money in tool wear.