Search found 229 matches

by Bob D.
Fri Jul 17, 2020 8:11 am
Forum: Lathes
Topic: Enco Lathe - Extended gib and tail stock clamp
Replies: 9
Views: 601

Re: Enco Lathe - Extended gib and tail stock clamp

Yeah, I screwed up in my reply, I meant compound and wrote cross slide. I knew the OP couldn't have really meant steadyrest...
by Bob D.
Thu Jul 16, 2020 10:39 pm
Forum: Lathes
Topic: Enco Lathe - Extended gib and tail stock clamp
Replies: 9
Views: 601

Re: Enco Lathe - Extended gib and tail stock clamp

Dan, To me it looks like the end of the gib is broken off. Generally a gib has a slot or pocket that traps a portion of the adjusting screw. The screw doesn't just push the gib, it also has to prevent it from being sucked in during movement of the cross-slide. I can't tell if those are metal chips/d...
by Bob D.
Tue Jul 14, 2020 8:26 am
Forum: Welding
Topic: Aluminium welding problem.
Replies: 10
Views: 695

Re: Aluminium welding problem.

Your only hope is to go back to a hammer and nails......
by Bob D.
Mon Jul 13, 2020 10:57 pm
Forum: Welding
Topic: Aluminium welding problem.
Replies: 10
Views: 695

Re: Aluminium welding problem.

You say your ground is negative.... are you using a DC mig? I TIG weld aluminum and that is done AC. Your results look like my TIG when I forget to change over from DC after welding steel.
by Bob D.
Wed Mar 04, 2020 7:25 am
Forum: Grand Scale Railroading
Topic: Brake System Design
Replies: 10
Views: 2928

Re: Brake System Design

Thanks for the brake pad info Kimbal.
by Bob D.
Tue Mar 03, 2020 11:17 am
Forum: Grand Scale Railroading
Topic: Brake System Design
Replies: 10
Views: 2928

Re: Brake System Design

I get being able to lock up the wheels and modulating from there..... At this point I'm trying to figure out how much mechanical advantage I need to design into the linkages for the shoe operating system so a pneumatic cylinder(s) can either operate it or overcome the spring force that applies brake...
by Bob D.
Tue Mar 03, 2020 9:02 am
Forum: Grand Scale Railroading
Topic: Brake System Design
Replies: 10
Views: 2928

Re: Brake System Design

Thanks for the reply. Tractive effort comes down to a line of contact between the rail head and wheel. My cast aluminum brake pad has 3 sq inches of contact area against a cast iron wheel. The wheel diameter must come into play too as it is a lever from the pad to the axle. So I'm unsure how to figu...
by Bob D.
Tue Mar 03, 2020 8:17 am
Forum: Grand Scale Railroading
Topic: Brake System Design
Replies: 10
Views: 2928

Brake System Design

My freelanced large scale loco has progressed to the point I'm designing the mechanical brake system. My question to all of you is this. How do you determine the force required to be applied to the brake shoes against the wheels to have effective braking? My assumption is you don't need any more bra...
by Bob D.
Fri Dec 27, 2019 9:28 am
Forum: Lathes
Topic: "Put it in 'R' for Race"
Replies: 12
Views: 5141

Re: "Put it in 'R' for Race"

Have several American lathes of that vintage where I work. They all reverse the motor electrically to change spindle rotation. Since your running a VFD I assume your motor is 3 phase. Find it hard to believe there are not two mechanically interlocked motor contacters in the electrical panel for forw...
by Bob D.
Fri Nov 08, 2019 9:48 am
Forum: General Discussion
Topic: Need to broach a square hole...
Replies: 8
Views: 2347

Re: Need to broach a square hole...

Layout your square hole. Drill out the corners with say a 1/8 drill. Put in the lathe, drill/bore 3/4” center hole. Use the lathe as a shaper to broach out the remaining indexing the chuck 90 deg. with a HSS tool. Finish up with some filing.