Ping Anthony

Have you tried any PCD inserts with chipbreakers like these:

http://www.youtube.com/watch?v=gLRJdMDvbpY

or these http://www.tirotool.com /
I have a customer with a chip control problem in aluminum and need to find something that will either break the chip or roll it up tight.
Carbide would be fine too, just so long as it works.
TIA
--

Dan

CNC Videos - <http://tinyurl.com/yzdt6d
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

IMO the trend towards trying to find a magic bullet where it concerns tool design when the goal is to solve basic chip control issues is unwarranted when considering that the effective application of simple and well known techniques like peck drilling etc generally provide excellent results given low quantity runs such as the one time RD work.
--




Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Agreed. This is a high volume shaft turning deal though, so it's worth the effort. Especially if they can get it to run overnight unattended.
--

Dan

CNC Videos - <http://tinyurl.com/yzdt6d
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Okay then yes molded chipbreakers definately work wonders for getting rid of hairballs...as you undoubtedly already know, the effectiveness of any particular molded chipbreaker geometry ( particularily the land width ) is largely dependant upon maintaining feed /speed as well as doc within a relatively narrow range..thinking I might even have geometry and feed speed recommendations for sorta thing as in earlier times the tooling research group at the lazy b had thorougly tabulated data for the turning of 7075 whereas our own cutter grinders would grind the chipbreaker in house to spec--Ill try and check on monday...pretty sure I had cribbed a copy for myself and if so maybe I'll scan the relevant portions.
--




Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'd appreciate it, even if only from an academic POV.
I'd like to elaborate on this particular situation as it has me fairly well pissed off. But I better not. I have no doubt that I can get the chip issue under control. The machine has a 2,000 psi 8gpm coolant pump plus a huge flood coolant pump. And it's rigid as all get out.
I already have some proper inserts coming too. They have a GP DCMT insert in there right now so I don't know how they expected that work.
Anyway, it would be a good excuse to try out one of those nifty inserts in the video at no cost to me. But I'd at least like some hope that they would make a big diff.
--

Dan

CNC Videos - <http://tinyurl.com/yzdt6d
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yup--even though your supplier will have guidelines it's interesting to see cutting parameters charted in a tabulated format alongside the groove location and geometry.

Well one nice thing about the molded chip breakers of today is that they arent as finnickey when it comes to doc--the land width typically being variable ( widening as doc increases )

Suggest supply the tooling rep with cutting data that are currently being used--this gives you the best chance of obtaining a performance base line and with little or no need to modify existing part program the initial tryout is not a difficult or time-intensive task.......once reliable chip handling is verified then perhaps tweek the insert and /or fine-tune production rates upwards via program modification.
--


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Dan, I haven't tried either, but that's about to change. I didn't even know those existed. Looks like a really good thing. Most of what we do now is a separate chip breaker. BTW, you need to make a trip south sometime :)
--
Anthony

You can't 'idiot proof' anything....every time you try, they just make
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'd like to come down there some day. If I ever have the excuse I'll get in touch.
Meanwhile, I saw an ad or something a short while ago. I'm about 99% certain it was from one of the Japanese tooling companies. They were touting PCD inserts with molded in chipbreakers. Of course I can't remember which one or find the info, so while searching the web I came across the two German companies and the video.
I'll see if I can get info on Monday. I'll let you know the cost, then later if they worked for us.
--

Dan

CNC Videos - <http://tinyurl.com/yzdt6d
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ran some parts today with the PCD inserts with the chipbreaker. We went with the ones from Becker. We started with a DCGT32.51-CB2. This chip breaker is supposed to be for larger DOC and higher feed rates. We were in the sweet spot for DOC and at the low end for feed rate. It didn't work. We had a very typical PCD chip. A long straight wire without any curl. Kicking up the ffed rate resulted in severe wrapping of the chip around the work. We ran a fairly large quantity of parts at 0.003" IPR with no issues with the chip wrapping or interfering, but that really wasn't what we were after.
So we switched to the DCGT32.51-CB1 insert. This is the finishing chipbreaker. We were over the recommended DOC (but plenty of PCD for the cut)for the chip breaker and were in the middle of the recommended feed rate. The first part we made very tight spirals which were breaking at about a 9" length. We kicked up the feed rate to 0.004" and the chips were breaking. Very short C and S shaped chips. Except in one area with a slightly different DOC. But we still had tight spirals around 4"-7" long and very straight. We kicked up the rpm another 1,000 and the situation improved.
We ran over well 100 parts and half filled the hopper with fine broken chips. Amazing.
I have to say these things really work well but are very sensitive to DOC, feed rate, and surface speed. We are running low SFM for a PCD at 1155 SFM, bit so far so good. The parameters of the cut are 7075-T651 Aluminum, 0.06" DOC, 1155 SFM, 0.004" IPR feed rate.
Very cool product. Well worth a try. In your case you should probably try all the styles and maybe all the vendors. I think there are three. Anyway with some playing around you'll be breaking chips. They come out of the conveyor like grey sludge.
Becker also offers wipers which we didn't get a chance to try. Due to the geometry of the cut we had to use the 55 degree insert. I hope to get an application for the wiper one of these days. If you get that to work that would make a serious gain in cycle time.
--

Dan

CNC Videos - <http://tinyurl.com/yzdt6d
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Great report Dan. I haven't had a chance to check those out yet, let alone order any for testing. Buried doesn't even begin to describe it.
--
Anthony

You can't 'idiot proof' anything....every time you try, they just make
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.