Tubing fish mouth

[deephis46]

What is the best way to fish mouth tubing? I have 4mm tubing..

Tyo

[sick86burban]

rat tail would be your best bet,more precise then a dremel, and everyone likes a nice tight fit joint rather then a sloppy loose one ;)

[J-FAB NOR-CAL]

Rat tail file,or chainsaw file,pretty much the same thing.Come in all sizes.

[War Pig]

Bench grinder.

[YoUnG_vErSiOn]

Originally Posted by War Pig

Bench grinder.

true, edge of the wheel makes an adjustable size, just keep going till you get the correct size.

[bob1961]

as said bench grinder then clean it up with 3/16" chain saw file ........bob

....

[badhoopty]

i notch with a dremel cutoff wheel and then finish the fishmouth with a 3/16" dremel chainsaw sharpening bit.

its a little bit costly but fast and pretty accurate...

[Big Daddy]

I just use a triangle file to put a small groove in the center then a rat tail to make the notch. It really doesn't take long at all once you get the hang of it. Just put the tube in vice with very little sticking out so it doesn't get a bunch of flex.

[dirtracer20]

hand grinder with a flap disc is the best method. this is my opinion from building dirt late model chassis when a end mill is not available.

[Duuuuuuuude]

Originally Posted by dirtracer20

hand grinder with a flap disc is the best method.

I disagree.

[deephis46]

How long did you guys fish mouth with rat tail file? I have tried 10 minutes one fish mouth

[sick86burban]

shouldnt take but a few minutes,thats thin wall stuff and should notch like butter.

[warriorsimi]

Originally Posted by bob1961

as said bench grinder then clean it up with 3/16" chain saw file ........bob

....

that is the way i built the showtime build, once you get started it with the bench grinder i put it in a vice and go at it cuts really quick.

[Big Daddy]

Originally Posted by deephis46

How long did you guys fish mouth with rat tail file? I have tried 10 minutes one fish mouth

It probably takes 2-3 minutes per joint of filing time.
I just put a dot with a marker on either side to indicate the direction I want it to go and line those up in the vise so I have a reference line when filing. The triangle file and grinder do the same thing. But my grinder isn't right by my bench and it takes forever to get up to speed so I use the file.

[bob1961]

Originally Posted by deephis46

How long did you guys fish mouth with rat tail file? I have tried 10 minutes one fish mouth

with my bench grinder it has the edges rounded a bit....then like said above i mark each side with a marker, then bout 2 seconds on the grinder will have it rounded just bout right....then a few strokes of the 3/16" round file cleans it up good, all in bout 4 seconds a joint....i have a piece of tube as a sample so i can see the fit....i never use my vise to hold the tube, just a leather glove and use my finger and thumb as guides for the file ....maybe i'll do up a video ........bob

....

[mjderstine]

i just use a chainsaw file. even with thicker walled stuff i can get a nice fishmouth in a couple minutes.

[deephis46]

Originally Posted by bob1961

with my bench grinder it has the edges rounded a bit....then like said above i mark each side with a marker, then bout 2 seconds on the grinder will have it rounded just bout right....then a few strokes of the 3/16" round file cleans it up good, all in bout 4 seconds a joint....i have a piece of tube as a sample so i can see the fit....i never use my vise to hold the tube, just a leather glove and use my finger and thumb as guides for the file ....maybe i'll do up a video ........bob

....

I have tried that, but it needs little bit practice for me to make a good mouth. Yup make a video for it

Originally Posted by mjderstine

i just use a chainsaw file. even with thicker walled stuff i can get a nice fishmouth in a couple minutes.

That's nice & clean joint...
And does the chainsaw file a triangle one?

[Postclanker]

Thanks for the picture mjderstine....I had no idea what this was about
You learn something new every day....love this hobby

[Charlie-III]

Originally Posted by deephis46

That's nice & clean joint...
And does the chainsaw file a triangle one?

A chainsaw file is round with a constant diameter. There are 3(?) different sizes and they have a fine tooth count.

I have a couple each of 1/8" & 3/16". I believe there is also a 1/4".

[mjderstine]

Originally Posted by Charlie-III

A chainsaw file is round with a constant diameter. There are 3(?) different sizes and they have a fine tooth count.

I have a couple each of 1/8" & 3/16". I believe there is also a 1/4".

what he said!

i use 3/16, as that is the dia of the tube i use. and yes there is also 1/4. the constant diameter is the best part since you never had to tweak it a lot. a rat tail file is a bit tapered towards the point, so you joint could be much less precise.

i dont start the mouth with a triangle file. just the chainsaw file. wear a leather glove on the hand that is holding the piece that is being filed too. it creates a lot of heat when you file these fish mouths, and you can even start to feel it through the leather glove. guys will also use a vise to hold the piece. but i feel like i have more control with it in my hand (that's what she said )

ah and since the chainsaw file is designed to sharpen, it will create VERY sharp edges, so be careful, you can easily slice your fingers with the fish mouth.