Bits and cutters question

[Eric Mims]

Is ok to use mill cutters in a CNC router? You know, the type that has that notch out of the shank.. or is it bad for the ER25 type collets?

This isn't to replace the great woodworking bits that are available and work fine, it is to find more appropriate bits for milling aluminum/brass stock.

[jrj5x5]

Is ok to use mill cutters in a CNC router? You know, the type that has that notch out of the shank.. or is it bad for the ER25 type collets?

This isn't to replace the great woodworking bits that are available and work fine, it is to find more appropriate bits for milling aluminum/brass stock.

I don’t know but I look forward to a qualified answer as well.

[james mcgrew]

well i don't know about qualified, but i ain't gonna be the first to try it!!

jim

[Eric Mims]

MSC is having a sale on their Accupro bits today and tomorrow, so I took advantage and ordered some of their 4 flute chamfering bits, solid carbide, 60, 90, and 120 degree. They were 50% off and so came to 9 bucks each.. I'll report back with any success, failures.

[jrj5x5]

MSC is having a sale on their Accupro bits today and tomorrow, so I took advantage and ordered some of their 4 flute chamfering bits, solid carbide, 60, 90, and 120 degree. They were 50% off and so came to 9 bucks each.. I'll report back with any success, failures.

I could use $9 bits as well
Also I have used a 4 fluted 1/4 mill cutter, end mill style for roughing in white oak and it worked fine.

[Eric Mims]

Actually, I believe all the ones I ordered are smooth shanked, not having the Weldon Flat.. I read on one spindle company page that it wasn't a great idea to use tools with Weldon Flats on the shank in a collet type holder since the tool is unbalanced. But I still don't think it would be an issue if one were using small tools and light passes anyways.. from what I understand, the flats are there on bigger tools when extra set screw is needed to hold the tool in place.

I found another page that had some good collet info and mentioned the flats and said they can indeed be used in a collet but may reduce clamping force up to 30% on tool.

http://www.mmsonline.com/articles/be-kind-to-to-your-collets.aspx

I don't think the smaller ones like mine even have them, but we'll see.

[jrj5x5]

. When tightening the nut, torque down on it only to the value specified for this nut. Use a quality torque wrench to observe this limit. Exceeding the torque does not provide more clamping force; it just leads to runout. In fact, the more force is applied, the more the top of the collet wants to twist with the nut. Too much force can actually twist the collet’s top, deforming the collet, which will increase runout and reduce clamping force.
Hope this helps it is from the link ED posted.

[james mcgrew]

rocklears sale

http://www.rockler.com/product.cfm?page=17227&ref_id=6271&ref_t=Z&originid=68576006

[KeithG]

Maybe it's just me, but I have had a lot more of the bits from RB Router breaking. They had a great deal on them at the show, or at least I thought so. Maybe it's just a streak of bad luck but we've had 4 or 5 in a row to break.
KeithG

[james mcgrew]

i just started using them, they did well with the melamine, i haver moved the cnc to the new shop and when i stareted it up i moved it with out lokking well "snap" goes one of my jb bits!!

[james mcgrew]

http://www.vortextool.com/images/chipLoadChart.pdf

[james mcgrew]

that is one of the best selections of tapers i have seen

jim

http://www.wttool.com/category-exec/category_id/13816/nm/4_Per_Side_End_Cutting_Tapered_End_Mills

[james mcgrew]

http://www.toolstoday.com/c-454-in-groove-cnc-insert-engraving-tool-body-replacement-knives.aspx

[TomM]

http://www.discount-tools.com/endmills1.htm

[james mcgrew]

new bit station

jim

[TomM]

http://www.hartlauer-bits.com/HartlauerBitsList.pdf

[james mcgrew]

for good info page three of toms last post is one of the best explanations of router bit use i have read!!

we have copy'ed it and poasted it at both router stations

jim

[Unabiker]

This isn't to replace the great woodworking bits that are available and work fine, it is to find more appropriate bits for milling aluminum/brass stock.

Sorry I'm late to the party. I cut miles of aluminum with my ol' Billhog using Onsrud O-flute cutters, #63-620. They are a little on the pricey side, but are really inexpensive once you see how long they last. Here's a link to the Onsrud pdf: https://www.onsrud.com/oc/pdf/O_Flute_Aluminum_Brochure.pdf

[james mcgrew]

thanks i have purchased some of onsruds "o" flutes but have yet to use them how about feeds and spindle speeds, any norms for basically pocketing??

jim

[Joey Jarrard]

Jim
the O flute bits from onsrud are great. We mill 3/4" plate with these at about 50 ipm with cooling mister with a depth of .1 to .15. aluminum comes in diffrent grades and this will need to be looked at as to speed. We get a smooth cut on 6061 this is a hard grade. what you want is a good chip this moves the heat away from the bit. we can cut 6061 stop the spindle and touch the bit it is cool to the touch. this is what gives you a long tool life. Southeast tool has a cutter that is comparable with onsrud the price is a little better.

But remember all CAMheads (owners) get 10% off list price from hartlauer and SE Tool from us.

that is my shameless plug today I am sorry. NOT!!! [lol]

[Unabiker]

For feeds n speeds, cutting .080" 6061-T4, I get nice smooth cuts at 18,600 rpm and 115 ipm. This is with a Koolmist water based mist dribbling on it. Chips coming off are pretty hot, but the bit stays nice and cool.
Most of my routines have some pocketing and some straight up full bit width cutting and I use the same feed rate for both. For the pocketing parts, I'm using a 95% stepover.

[james mcgrew]

thanks

jim

[Eric Mims]

what angle are you going into the aluminum at, or are you always coming in from the side?

[Unabiker]

I'm plunging straight down with the plunge feed rate set at 30% of the cutting feed rate. Once it's through, everything is coming at it from the side.

[Joey Jarrard]

I plunge to I go the set bit depth of .1" and do it at about 15 - 20 ipm. this slow rate gives the cutter time to void the chips.

Biker thanks for your feedback its great when we all help eachother this will always set us apart from the others.
Thanks

[Unabiker]

Always happy to help.
Now if I could just find a way to keep the aluminum chips out of my boots.

[Eric Mims]

just to clarify, you both are plunging straight down at a 90 degree angle? I was told to always go into aluminum at a shallow angle. The Onsrud you guys use does ok with straight plunge?

[Unabiker]

Yup. Straight down at 90 degrees. I'll post a Youtube vid of it later on this evening.

[Unabiker]

Here are a couple of short aluminum cutting videos that I shot this afternoon:
http://www.youtube.com/watch?v=Ax8YDKhmoHA
http://www.youtube.com/watch?v=KGs2H1JG6D0

[Joey Jarrard]

[fantastic] looks great man, the router looked good. Do you find that the roller hold down works good or fair? also do you have any marks left by the chips.

The chip load looed great keep up the cutting and posting you are a asset to have here, Thanks

[Unabiker]

The rollers work ok for their purpose. The upcut bits generate a bit of lift on the aluminum, and the rollers do a good job controlling this. My shop has quite a bit of humidity variation, which plays havoc on my spoil board flatness. The rollers help keep this in check to a lesser extent. I am also using 9 drywall screws per 4'x4' sheet of aluminum to keep everything in place.
Just for yucks, I played with the feed rate yesterday. I was able to really crank it up to 170 ipm without seeing any decrease in cut quality. I'd go faster, but I will have to go back and re-program things in visual mill as the original feed rate was set at 85 ipm.
FYI, the chips coming off in the video are about .013" thick.

[james mcgrew]

http://www.ncprogramming.com/index.html

[Russ Revels]

I am getting to the point that I need to start thinking about surfacing my spoil board. What bit is recommended for resurfacing? I would hopefully would only have to take about .05 off the board.

Russ

[james mcgrew]

i use a 1.25" dia mortise type bit and mill at .015 on the first pass and if this cuts the entire table level good, if not i do another pass. got a video on this coming

jim

[Russ Revels]

Thanks Jim,

I will contact Joey and see about getting one of those bits for my tool rack. I will be watching for the video.

I am not in a hurry since I will be in Rhode Island for the next month. That is if the snow lets up enough to drive a truck up there.

Russ

[Unabiker]

For surfacing the spoilboard, I'm using a 3/4" 2 flute straight cut bit, taking .005". Bit turns at 12,500rpm, feed at 400-600 ipm. Takes 15-20min to do the 4'x8' board.

[Russ Revels]

I will give that a try when I get home. I have a 3/4 straight bit in my router bit set.

Thanks,
Russ

[Southeast Tool]

The bits with the weldon flat will hurt the collets over time. the biggest thing also is that the runout will/may be increased from incorrect holding of the tool.