By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

face milling

All Topics | Latest Posts

Search for:  in Thread Title in  
bricky30/12/2020 08:12:38
482 forum posts
48 photos

I have a arc euro three insert face mill cutter and using on a SX3 mill.I have been taking .5mm cuts and with new inserts and the head wags side to side at 400 rpm.Is the cut to deep and the feed to fast.I find that my flycutter at 75mm sweep at.5mm and 400rpm creates barely a murmer at the head ,can someone put me right.Feed for both was 1" per minute.

Frank

David George 130/12/2020 08:24:27
avatar
1521 forum posts
472 photos

Hi Frank what diamiter is the cutter and what style is the tip and what material are you cutting. It sounds like you are running it to slow perhaps a picture may help if you can post as well.

David

not done it yet30/12/2020 08:35:37
5776 forum posts
20 photos

The diameter of the face cutter and workpiece width may have some bearing on feed rate and depth of cut? Is that 75mm too? Your fly cutter, all things being equal, will be cutting three times the effective tooth load of the three-insert jobbie.

Martin Connelly30/12/2020 08:49:58
avatar
1690 forum posts
181 photos

If the tool is Ø75mm and the material is mild steel then you should be running at about 300rpm and upping the feed to somewhere between 5 and 10 inches per minute. You are over speeding and under feeding which results in rubbing not cutting.

400 rpm and three cutting edges is 1200 passes per minute at the cutting face. In that same minute you are travelling 1" so the result is each tooth is trying to cut off 1/1200" which is 0.00083"/0.021mm. This is definitely going to be rubbing when using carbide inserts.

Martin C

Alan Waddington 230/12/2020 09:08:41
523 forum posts
87 photos

Have you got a link to the tool, or a photo ? Asking because i bought a cheap 3 insert face mill once (Not from Arc) and it was useless, could never get a decent cut from it, and my mill is industrial sized.

Try running it with one insert and see if that makes any difference.

Martin Connelly30/12/2020 09:30:07
avatar
1690 forum posts
181 photos

Using one tooth instead of three is the same effect as upping the feed by a factor of three. Maybe you should have tried a faster feed than you were using.

On Monday I was using a Ø16mm 2 insert cutter on aluminium at 1300rpm and 350mm/minute feed. This produces large chips not small particles of debris and with a very nice finish.

Martin C

PS if there is a runout error of maybe 0.002" from the highest to the lowest insert then the 400rpm and 1" per minute feed will result in only one tooth cutting, one possibly rubbing and one not doing anything apart from sweeping away debris.

 

Edited By Martin Connelly on 30/12/2020 09:55:28

JasonB30/12/2020 10:08:06
avatar
Moderator
20248 forum posts
2207 photos
1 articles

Sounds more like you are using one of the indexable endmills that take the triangular inserts that ARC no longer do than the current face/shell mills.

I've had a Glanze version of the same too in 40mm dia and get a decent finish with that on steel and cast iron. Probably run that at 800rpm and feed of approx 150mm/min. If you have a 50mm dia one then around 650rpm would be a reasonable starting point and same 120mm/min feed

bricky30/12/2020 10:49:02
482 forum posts
48 photos

That is correct Jason it is 40mm.I have been milling 2" flat mild steel.

Alan Waddington 230/12/2020 11:31:12
523 forum posts
87 photos
Posted by Martin Connelly on 30/12/2020 09:30:07:

Using one tooth instead of three is the same effect as upping the feed by a factor of three. Maybe you should have tried a faster feed than you were using.

PS if there is a runout error of maybe 0.002" from the highest to the lowest insert then the 400rpm and 1" per minute feed will result in only one tooth cutting, one possibly rubbing and one not doing anything apart from sweeping away debris.

Agree with the above, using one insert pretty much puts you back to using a fly cutter, but should rule out any issues with the arbor/body alignment. On the cheapo i had, the triangular inserts were so far out from each other it was never going to cut correctly, you could see the differences by eye. Plus the actual insert angle looked wrong.

Martin Connelly30/12/2020 13:08:39
avatar
1690 forum posts
181 photos

This is a "Little Hogger" Ø25 two insert milling tool. The inserts are as plain as you can get with a flat face. The workpiece is just a bit of scrap mild steel. This is what correct feeds and speeds does.

RPM 860

Feed 150mm/min

Depth of cut 0.5mm

Machine is the much maligned round column mill/drill.

Martin C

p1150564.jpg
JasonB30/12/2020 15:01:37
avatar
Moderator
20248 forum posts
2207 photos
1 articles

So this is my 40mm one running at 800rpm, feed of about 200mm/min, 0.5mm DOC doing a full width pass on some 40mm wide EN3. Bit of gear noise from the head at the end of the cut as the engagement falls off and does not quite pass the Sharpie test but not too bad a finish, would benifit from a finishing pass at about 100mm/min.

 

Edited By JasonB on 30/12/2020 15:40:38

bricky30/12/2020 15:23:19
482 forum posts
48 photos

Tank you all, I was feeding to slow and rpm not fast enough ,it is great to have such a quick response and a great forum.

Frank

old mart30/12/2020 15:55:58
2829 forum posts
178 photos

I have a Ceratizit 50mm shell mill with 5 inserts and on the side is the maximum rpm. 12200 maximum, and in the Ceratizit pdf it says that the screws should be changed at the same time as the inserts if that speed is used. The inserts have either 4 or 8 stations before they are worn out. I can only manage 3000 rpm and the depths and feed rates depend on the power available. Most hobby machines run out of speed before the carbide tools do.

Ron Laden01/01/2021 07:56:00
avatar
2173 forum posts
432 photos

Well be it right or wrong it seems that I run my 2 insert 25mm diameter end mill quite a bit faster than what the books and charts suggest. I have only been machining for a couple of years so not that much experience but I tend to let the machine (mill and lathe) the tooling, the cut depth, speed and feed and the finish point me in the right direction.

With the 25mm end mill I run at the mills top speed 2500rpm for cuts up to 1.5mm deep, the mill and the inserts are happy, the finish is excellent so I don't query it.

With steel and cuts up to 1.0mm deep I run with 1750rpm on EN1A and 1500 on EN3, 1250 to 1500 on EN8 though with a small part recently in EN8 the cutting area was quite small and 0.5mm deep so I went with 1750 and it was fine with a very good finish.

My thinking is that the tool is a 2 carbide insert cutter and it should be run in the higher speeds but I could be wrong and quite prepared to be corrected but as I say I am basing it on results that I get with the tool.

Martin Connelly01/01/2021 09:13:17
avatar
1690 forum posts
181 photos

Carbide will quite happily cope with high speeds but two issues are that as your rpm increases the feed rate needs to go up to keep the cutting process going and you have hotter chips flying farther and faster. If you only have manual feed or limited feed rates it is better to reduce the rpm to suit. At 2500rpm and 2 edges you would need to feed the work at about 450mm/minute, hard work if you are cranking a handle to do it.

A lot of machines in the hobby world have limited power so the compromise is between speed and torque means that lower speeds are chosen to give higher torque for cutting (geared or pulley drive speed selection). With electronic speed control lower speeds can reduce torque so they may need setting to a higher speed to get the best results.

Unless you have flood coolant rubbing creates heat in the tooling and workpiece that may cause issues if you are trying to achieve an accurate size. If you look at my video above you can see that I am producing chips that are going blue so I am in the good working range for the carbide inserts. The workpiece and tooling was not noticeably warm after the process as the chips carried the heat away.

Martin C

old mart01/01/2021 16:08:14
2829 forum posts
178 photos

When the edges are sharp, they do not impart much heat to the work, but if the work gets very hot, it is time to look at the insert. It may be possible to sharpen the fronts of the triangular inserts on a diamond lap. I have one which is about 150 x 70mm and double sided, 400/1000 grit. If used wet, that type could give the inserts a new lease of life. For a twin insert cutter, you would have to sharpen them in pairs and match the thickness so they cut evenly in the tool.

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Support Our Partners
ChesterUK
emcomachinetools
Warco
Eccentric July 5 2018
JD Metals
cowells
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest