Machined Aluminium Coax - Planning to build

[jackssmirkingrevenge]

Why didn't I thread them on ? Good question. Short answer; I suck at cutting threads.

I hear ya!

[Hrawk]

Slowly coming together.

Didn't get a lot done today. Tapped the rear plug and blowgun for the schrader valve.

Ordered some M4x6mm bolts for securing in the end cap & barrel cap.

[jackssmirkingrevenge]

This is going to be a nice little powerhouse when it's done.

It will be crying out for a scope and stock when its done, something like this: http://www.spudfiles.com/forums/step-by ... 17673.html

[Gun Freak]

Every time I log on, all I want to do is buy a lathe. Thanks a lot, man.

[jackssmirkingrevenge]

Buy it today before tomorrow, I wish I had bought mine with my first couple of paycheques.

[Hrawk]

Ok so I kinda got a bit sidetracked these last few weeks with exams and other boring stuff hence the delay.

Taking your advice I tracked down some nylon rod for the piston.

Today I quickly knocked up the barrel support/spacer and the piston.

Sure they may not look fantastic but they're out of site so I don't mind.

I need a bit more practice with the turning of the nylon but it's a nice fit and I'm sure more than functional.

Rubber face has just been epoxied to the piston and I should have it assembled for it's first test tomorrow.

[al-xg]

I need a bit more practice with the turning of the nylon but it's a nice fit and I'm sure more than functional.

Looks like you're moving in too fast with the parting/facing. When it's burning the material like that it will also tend to make a squealing sound. Use a load of coolant if you can.
What RPM did you run that at?

[matti]

I need a bit more practice with the turning of the nylon but it's a nice fit and I'm sure more than functional.

Looks like you're moving in too fast with the parting/facing. When it's burning the material like that it will also tend to make a squealing sound. Use a load of coolant if you can.
What RPM did you run that at?

You dont need coolant with nylon/plasitcs. But use HSS tool, and it needs to be very sharp ! Nylon is too soft for carbide insert tools.

[al-xg]

You dont need coolant with nylon/plasitcs.

It definitely helps with PP, PVC, ABS, PVDF, even POM but mainly to stop it from going everywhere.
Interestingly, the place I worked at used carbide tips all the time but that could also be because a lot of the harder plastics such as PPS were glass or graphite filled.

[Gippeto]

You dont need coolant with nylon/plasitcs. But use HSS tool, and it needs to be very sharp ! Nylon is too soft for carbide insert tools.

X2 Much better results with SHARP HSS on Nylon, Nylatron, Teflon or Delrin. Use an extra fine diamond file to clean up and polish the edge after grinding.

Edited for shpelung

[GonzoInferno]

Nylon will wear well in the launcher. But it will still be quite a thump towards those small M4 screws holding the rear cap on. And yes, the softer the workpiece material...the sharper the tooling needs to be.