How Would You Make This Cutter

[CJ5Dave]

This is a cutter that goes on the end of an 18 inch tube, driven by a drill, to sample hay. I can buy the tubing, make the drill arbor end, but after I use up the cutters I have on hand I will have to buy or make these. I just bought a vertical mill, and looking over time for needed tooling. Turn it on the lathe first. Do I need an indexing head? What end mill cutter?

 

[D.sebens]

Probably hair brained but what if you knurled the end with a straight knurl. I don’t know how sharp it has to be for cutting hay.

 

[Martin W]

Maybe have a sacrificial rod that goes thru the cutter for support and between centers on the lathe, while you are grinding or cutting the angle. Maybe try knurling like D.sebens suggested for the cutting end with the rod still in place
You will likely need to harden afterwards.
Martin

 

[GeneT45]

Roughing out the shape on a lathe shouldn't be too hard. I'd try cutting the teeth in with a checkering file. If you need a lot of them, I'd probably make some sort of jig, but for one or two it probably wouldn't take more than a few minutes each. Bonus - you have a tool you can use to sharpen them in the field!

GsT

 

[CJ5Dave]

The ones I have are dull ones I resharpened with a file. Wanting to make several of them to sell. Thinking something like a dividing or indexing head.

 

[benmychree]

Does nobody make/sell these commercially?

 

[homebrewed]

1. Modify a hole cutter?

2. Awhile back I was playing around with making a castle nut-like piece, using my RT to cut the fingers. Adding more fingers would turn it into something like your item. It wouldn't have to be all that accurate for your needs. You probably need to harden it.

 

[woodchucker]

I would rough the outside shape, then cut the teeth with a double beveled cutter in an arbor.
Then I would put it back in the lathe and bore it.

 

[TMP-NET]

Admittedly a novice here so I defer to those more experienced but here's my 2c....

Considering the desire for production and the actual use..... The most precise dimension is the mounting end, as the cutting end likely has broader tolerance allowing a slight design modification...

- Start with thick walled pipe if possible,
- Envision a line of product facing cone to cone and back to back.
- On the lathe, repositioning as needed
- First turn down a shallow flat that will become the teeth
- chamfer the leading edge to make it "sharp"
- straight knurl the flat creating the teeth
- turn the taper
- turn the mounting portion to diameter but 2x length
- bore interior to size (if needed) but to 2x depth
- Part off the first finished part
- turn the next taper (opposite of first)
- turn a 2x teeth flat
- straight knurl the flat
- part off with a sharply angled chamfer/parting tool, creating the teeth as the second item separated
- Repeat.......

 

[CJ5Dave]

Yes, the cutter can be purchased from the competing manufacturer, but the cost uses up all the profit. If I have a $2000 Bridgeport sitting in the middle of the shop floor, would like for it to earn something.