Fluting Barrels Question

[GNERGY]

I have fluted a couple straight barrels but not tapered, how do you guys hold them. I will be using my Bridgeport and ball end mills.
Pics would be nice.
Thanks
Tarey

 

[Dusty Stevens]

Make them level with a dividing head to index. Also you need the horizontal mill attachment with flood coolant and a power feed thats slow slow. Flutes wont look right with a ball mill IMO

 

[ridgeway]

I've never fluted a barrel, but if I would set up a BP I would chuck it up in a index head or rotary table and support other end with a tailstock or center. Then slide an angle plate up against the middle to keep from deflecting. Then get a side cutter with desired radius in it and let her rip in low gear and a slow feed. Lots of tap magic steel or compare able cutting oil.

 

[Dusty Stevens]

A machine vise in the middle not bolted down clamped on the barrel helps vibration

 

[Will Henry]

I set the barrel level and use a convex slotting cutter on the side. I can set the taper to what ever I want. I use the vise, wide open, with the movable jaw opposite the cutter. This jaw can the be used to support the barrel or, if the barrel has a swamped or curved contour, it can be used to bend the barrel to where the side being cut is straight. WH

 

[Roeder]

Make them level with a dividing head to index. Also you need the horizontal mill attachment with flood coolant and a power feed thats slow slow. Flutes wont look right with a ball mill IMO

Well, unless you do it on a VMC. We just program a gentle vertical radius entry and exit move and the result looks perfect.
I know some guys that use a 3" by 5/16' groove cutter on an arbor in their vertical mill and cut the flutes from the side, just indicating the setup so that the side you cut on is parallel. About like WH describes. It does need some extra back up against the opposite side of the barrel to keep it from chattering.

 

[paperpuncher]

If you were willing to use a side cutting tool you can use a couple big hex nuts with set screws Just bore the nuts so they fit on each end and secure with a set screw Basic machining from there You could do it with a ball mill this way but it would be more involved and probably easier to use a dividing head and tailstock Also a mag chuck like on a surface grinder clamped to the table and up against the side opposite the cutter works pretty good to help the chatter

 

[GNERGY]

I have fluted only straight barrels so far, didn't have an indexing head, so here is an easy fix. I used a hex fitting and put some set screws in it to attach to the barrel and then used my machinist level on the flats to do equally spaced flutes. I have since picked up an indexing head. Coated ball end mills worked really well, don't need flood coolant, manufacturer recommends air blast for chip removal, plus I am feeding it really slow, I have time on my hands. I have a couple tapered heavy varmint hunting barrels I want to flute. I did have a gentleman send me a pic of his set up that will help me. I am going to flute my new F Open barrel because it will finish at 32 inches long and I shoot off of a bipod.
Anybody else have any pics of their setup to share.
Thanks
Tarey

 

[Dusty Stevens]

I like those jacks

 

[Shrek]

I like those jacks

Look pretty easy to make too !

 

[DaveTooley]

Here's my setup I've done hundreds and hundreds of barrels using this setup. 5C collet spinner and an adjustable center on the muzzle I made which is nothing more than an angle block with 3" long threaded center at the correct height to match the collet spinner. Indicate on the side of the barrel to align the barrel. Easy to get uniform depth or tapered depth if you're so inclined. For smaller barrels I use the v shape and a capture screw to eliminate spring back. For larger barrels I turn it over and use the flat side. Mounting studs are off center so I can quickly spin them out of the way when I'm rotating the barrel or changing one out. I use two per barrel for rigidity most of the time.

 

[shortgrass]

I much prefer a cutter such as this one over ball end mill. More teeth, 10 to be exact.

 

[DaveTooley]

Here's where I get my cutters. Reasonable sharpening rates and they will make you anything you can dream up.

AB Tools, Inc. | Carbide Cutting Tools and Milling Tools

AB Tools Inc. is a leading manufacturer of carbide cutting tools, mills and accessories. We even use our own products in our day-to-day operations.

abtoolsinc.com

 

[shortgrass]

I don't have pics anymore of my set-up, at least not in this 'puter. But, it consists of my #2 dividing head and its' center and 2 angle plates , for back-up. Now days, I use the 10 x 54" vertical mill with CNC at the shop, where I work, instead of the 'manual' in my gunsmith shop. The CNC is 'conversational', and the program is easily altered to 'fit' the barrel taper. We have a 4th axis, but I have yet to mount it for a fluting job, as I only cut flutes for myself. I still just use a dividing head, its' center and a couple of angle plates to keep deflection down. The dividing head I use is 'keyed' to the table slots. Always been close enough I can see no deviation in flute depth by eye. The only difference between the manual and the CNC is the surface to be cut needs to run parallel on the manual, which can take some time to set-up. And, the manual is belt drive so I can not set cutter RPM just where I want it. The CNC is variable speed, just enter the number.

 

[shortgrass]

Whatever cutter you choose to use, it can not be turned faster than it is calculated to turn, but feed rate can be altered. Select the proper feed rate, and the machined finish of the 'grooves' will show. Feed too slow, and the finish will be rough, feed too fast and you risk breaking your cutter. 70-80 SFM seems to be about right (for HS tooling), IMO and experience.

 

[ridgeway]

Here's my setup I've done hundreds and hundreds of barrels using this setup. 5C collet spinner and an adjustable center on the muzzle I made which is nothing more than an angle block with 3" long threaded center at the correct height to match the collet spinner. Indicate on the side of the barrel to align the barrel. Easy to get uniform depth or tapered depth if you're so inclined. For smaller barrels I use the v shape and a capture screw to eliminate spring back. For larger barrels I turn it over and use the flat side. Mounting studs are off center so I can quickly spin them out of the way when I'm rotating the barrel or changing one out. I use two per barrel for rigidity most of the time.

I like it...slick idea!

 

[Dusty Stevens]

Here is the best tailstock ive found. Easy to set the height to make the barrel parallel

Adj. Tailstock For 8" & 10" Rotary Tables - Grizzly Industrial, Inc.

This Adjustable Tailstock provides the support you need for longer workpieces. MT#2 taper. Overall size: 7-3/4" x 5" x 11". Mounting slot size: 1/2" x 7/8".

www.grizzly.com