tube notching / fish mouthing etc

If you don't want to invest $$$, look for a program called "winmiter".Its freeware and very basic, but works fine.

You input the diameters of tubes you are joining and the angle of the join and it outputs a template you print, cut out and wrap around the tube, which gives you the line to grind/file to for a good joint.

Try this... www.harderwoods.com/pipetemplate.php

wrap a piece of paper round the tube and tape it up so you have a cylinder.

slide the paper off the tube.

flatten it.

line the the end of the paper up with the open end of the tube.

draw round the tube.

( at this point you should have a rectangle of paper with a circle drawn on it... )

next cut the circle exactly in half.

then cut out the semi-circle.

open the paper cylinder back up

slide it back onto the tube and draw round it.

remove the paper and grind to your line.

then keep offering it up and reaming the edge till it fits snug.

hope this helps. I'm not very good at explaining stuff...

this is basically what that programme does.

this is true, but from the description of what he wants to do, i pictured it would be a 90 ( dint know how to do the degree symbol ) join.

I have used that one. Very simple and works great.

you can buy hand operated, guillotine style notchers, we use them at work, wouldnt be cheap though and no good for anything other than 90 degrees!! don't forget that your going to lose 8 or so mil off your length when you notch it, probably wont affect you but worth noting!

Interesting looking assembly in that pic. What was the wall thickness out of interest? I tried making a jig for doing this a long time ago by drilling out a short offcut of steel bar to make a doughnut shape and then boring a hole at the right angle into the side of it in a four jaw chuck on the lathe. The idea was you insert the tube and use it as a guide for a drill the right diameter. It made a right mess as the big pillar drill wrapped the tube round into a big knot and sent the vice holding it across the workshop. So don't do it that way

The tubes in my pics above are 3mm wall but took about 10 minutes each to do: chop out a V shape with a cutting disc, round it out with a flap wheel and finish off with a half round file. That online coping tool puts axial lines in at 90 degree intervals which make a handy guide where to stop cutting each side of the V. Would have thought the same technique would work ok with thinner wall tubes too.

I always just use a 4.5" grinder with ceramic flap discs for spaceframes, haven't found anything faster yet...

Hi-What book or magazine is that info in? It looks very useful-and might go well with tea too!!