weird cut

[stevehuckss396]

Hello Men!


I am needing to cut an unusual slot. I am making a whistle and need to cut 4 tubes with this profile to make the blow holes. I cant use an end mill because the corner is not a right angle. I was thinking about a band saw and file but I would like to keep some form of precision as I don't know if the sound will be affected buy the shape of the notch.

Any ideas on how to cut 4 of these exactly the same?

 

[aonemarine]

This is one of those things where an old shaper works out well. You can do it with a dove tail cutter then trim back the little jib with a file or saw.

 

[Swifty]

You could make up a quick cutter, a bit of HSS parting blade soldered to a mild steel shank, then grind the end at 15deg. I have a few cutters that I made this way, some just have radius corners, others have intricate profiles.

Paul.

 

[Scott_M]

Hi Steve

You did not say what the material was. Or how thick the wall is.

With a surface grinder it would be a very simple matter of dressing the wheel at 15 degrees. Without one you can still do it in the mill with a mounted stone dressed to the proper angle. For a small job like that, I do not think material is a big issue.It would even work well on Brass or alum.

I say grind it.

Scott

 

[stevehuckss396]

Thanks for the suggestions. I'll look into both ideas!

 

[AussieJimG]

Do you have any photos Swifty?

Jim

 

[stevehuckss396]

Hi Steve

You did not say what the material was. Or how thick the wall is.

With a surface grinder it would be a very simple matter of dressing the wheel at 15 degrees. Without one you can still do it in the mill with a mounted stone dressed to the proper angle. For a small job like that, I do not think material is a big issue.It would even work well on Brass or alum.

I say grind it.

Scott

I should have mentioned it is aluminum tube. Don't know what wall thickness yet as the mail man still has it.

 

[reefman]

if you have acsess to a tooling grinder you could modify a endmill or like scott said you could use a grinder with a 15 degree angle on the face of the wheel.

 

[jwcnc1911]

How accurate does it have to be? If it's pretty forgiving you can make it many ways. If you want precision you will need a form cutter or use a grinder. I recommend a grinder, you will be greatly pleased with precision and surface finish.

If you can't come to a conclusion you're happy with, PM me - I'll grind you some. It looks pretty simple. I could set them up and grind the feature in stock and send it to you for finishing to length and width.

 

[stevehuckss396]

How accurate does it have to be? If it's pretty forgiving you can make it many ways. If you want precision you will need a form cutter or use a grinder.

By precision I meant better than a band saw and file. I'm just looking to make all 4 as close to the same as I can.

I am considering making a cutter and tilting the head on the mill 15 degrees.

 

[Scott_M]

The only problem with a cutter is not distorting the thin wall tube. Grinding would be more forgiving and have less cutting force.

Scott

 

[canadianhorsepower]

Steve----
:idea: how about using a fly cutter you could grind your
cutting tool to specs. and securing the 4 pieces side by side
they would be identical after only one x pass on the mill

my 2 cents

Luc

 

[jwcnc1911]

Great idea Luc, i didn't think about a flycutter. So rarely use a manual mill any more.

With a flycutter you'd only have one tool to grind and would get a surface finish that is pleasing.

 

[canadianhorsepower]

Great idea Luc, i didn't think about a flycutter. So rarely use a manual mill any more.

I use flycutter on my CNC mill to clean large area

maybe I'm lazy :fan:

 

[RonGinger]

Several years ago the New England Model Engineering Society ran a demo at Cabin Fever where we used a lathe and mill and made a neat brass whistle with a slider. We handed them out to kids and drove everyone at the show nuts with them.

One of our guys made a fine cutter to make that cut- like a dovetail cutter but upside down. Ive still got the cutter, Ill loan it you want it, send me email.

 

[Paulsv]

Since you are cutting aluminum, you could use a dovetail router bit. They are available in different angles, including 14 degrees. Do a search on "dovetail router bit 14 degree." If you are worried about distortion, just take small cuts instead of cutting it in one pass.

 

[stevehuckss396]

The only problem with a cutter is not distorting the thin wall tube. Grinding would be more forgiving and have less cutting force.

Scott

I don't have a grinder.

 

[stevehuckss396]

Steve----
:idea: how about using a fly cutter you could grind your
cutting tool to specs. and securing the 4 pieces side by side
they would be identical after only one x pass on the mill

my 2 cents

Luc

I don't have a flycutter but I could get one. I was thinking of making a cutter so I could set the head of the mill to angle and setup the tube horizontal in the vise. Setting the tube to 15 degrees seems like a accident waiting to happen.

 

[stevehuckss396]

Since you are cutting aluminum, you could use a dovetail router bit. They are available in different angles, including 14 degrees. Do a search on "dovetail router bit 14 degree." If you are worried about distortion, just take small cuts instead of cutting it in one pass.

I'll check into it, thanks

 

[stevehuckss396]

Several years ago the New England Model Engineering Society ran a demo at Cabin Fever where we used a lathe and mill and made a neat brass whistle with a slider. We handed them out to kids and drove everyone at the show nuts with them.

One of our guys made a fine cutter to make that cut- like a dovetail cutter but upside down. Ive still got the cutter, Ill loan it you want it, send me email.

Thanks Ron!

If i'm still stuck maybe I can pick it up from you at Zanesville if you are going.