Search found 188 matches

by mrfoo
Wed Nov 18, 2020 3:28 pm
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

It is certainly true that, where what you're making doesn't have to interface with some other precision part, you don't ultimately care about exact dimensions. However, you do care about fit, and that requires measurement. Take the example of a sliding fit, sub 10mm piston in bore, not uncommon in w...
by mrfoo
Tue Nov 17, 2020 1:20 pm
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

Hey, that's not totally cheap shit throwaway stuff, it'll probably be more than OK. Wedge style is a good call. Watch out for chatter, a QCTP brings the tool out away from the topslide, effectively it's hanging out in the void, any slop in your gibs will show itself here, particularly if you're doin...
by mrfoo
Mon Nov 16, 2020 7:11 am
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

I'd suggest you need metrology stuff more than you need a QCTP. At the very least a plunger type comparator and a finger type DTI, plus a decent mag base. The indicators you can get new from SHAHE on AliExpress, but avoid chinese mag bases like the plague - get yourself a good quality second hand on...
by mrfoo
Wed Nov 11, 2020 1:57 am
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

I kinda wish mine had automatic feed and thread cutting :) How's accuracy? Have you done all the alignment checks? If you don't have a machinist's level to level the ways, it's worth doing a quick eccentricity / alignment check using "Rollie's Dad's Method", i.e: Take a reasonably long piece of rigi...
by mrfoo
Tue Nov 10, 2020 1:12 am
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

Do you mean between movement and display? Yeah. My (cheap, admittedly) digital calipers have a noticeable "catch up" time between any fast movement and the display finally catching up. Even the Mitutoyos have it to a lesser extent, although I believe in that case it's more to do with LCD latency. I...
by mrfoo
Mon Nov 09, 2020 1:27 am
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

Neat.

Do they have the slight lag we see from, for example digital calipers? What happens if you run the carriage fast?
by mrfoo
Thu Oct 29, 2020 1:27 am
Forum: Pneumatic Cannons
Topic: PVC Primer/Glue says DO NOT TEST WITH AIR
Replies: 8
Views: 727

Re: PVC Primer/Glue says DO NOT TEST WITH AIR

PVC primer and cement are solvents. They physically attack the surface of the pipe and fittings, and can produce weak spots exactly where you don't want them. PVC pressure rating charts give the rated pressure for constant pressure conditions, with the pipe properly supported, and without pressure s...
by mrfoo
Mon Oct 26, 2020 6:52 am
Forum: General How-To & Discussion
Topic: JSR's workshop chronicles
Replies: 58
Views: 10412

Re: JSR's workshop chronicles

Nice, a much cleaner setup than my workshop. Hell, even your rustic stock stand is cleaner than my workshop :) I like your mill vice. Watch out with the LEDs, depending on the type they have a strobe effect that can make spinning things appear to be still, or jut simply give you a headache if you're...
by mrfoo
Thu Oct 22, 2020 6:25 am
Forum: Pneumatic Cannons
Topic: Concerning video of a Piston Valve Cannon bursting
Replies: 10
Views: 650

Re: Concerning video of a Piston Valve Cannon bursting

Do you think his can suffer the same fate as theres ? Don't make me bring out Bob the Angry Flower. It's a 2" cannon, as opposed to the original's 3". For the same piston construction, the piston will have a mass that is at least 4/9 (2^2 / 3^2) less than that of the larger cannon. The force applie...
by mrfoo
Thu Oct 22, 2020 12:24 am
Forum: Pneumatic Cannons
Topic: Concerning video of a Piston Valve Cannon bursting
Replies: 10
Views: 650

Re: Concerning video of a Piston Valve Cannon bursting

Do you think it would of been better to put a funneled reducer from the chamber to the barrel instead of an abrupt one? No, I think it would have been better to not use PVC. My guess as to what's happening is that the piston shoots backwards as intended, the pressure behind it perhaps blows off the...
by mrfoo
Wed Oct 21, 2020 12:26 am
Forum: Pneumatic Cannons
Topic: Concerning video of a Piston Valve Cannon bursting
Replies: 10
Views: 650

Re: Concerning video of a Piston Valve Cannon bursting

There's a lot of mass in a 3" piston, and PVC is fragile. The break at the barrel end was clean and exactly at the stress riser where the reducer meets the valve body, looks like shock fracture rather than pressure rupture. Lesson to learn - don't do that. At 2:00 or so, he says "That's not funny. I...
by mrfoo
Sun Sep 20, 2020 3:05 pm
Forum: SpudFiles Discussion
Topic: pages won't open
Replies: 18
Views: 1540

Re: pages won't open

Thanks for all your work, man.
by mrfoo
Fri Sep 11, 2020 5:40 am
Forum: SpudFiles Discussion
Topic: pages won't open
Replies: 18
Views: 1540

Re: pages won't open

All appears to be working again for me, many thanks to @PCGUY
by mrfoo
Mon Sep 07, 2020 1:44 am
Forum: BB, Airsoft, and Pellet Guns
Topic: Let's talk nerf blasters
Replies: 4
Views: 500

Re: Let's talk nerf blasters

I could always make my own, but it would be too powerful and might kill someone, so that idea is out.
I thought that was the idea?

Seriously, though, 150 bucks for a (high performance, admittedly) plastic toy gun? Tha fukk? I'd be far more inclined to try the nexus pro.
by mrfoo
Sun Aug 30, 2020 3:36 am
Forum: SpudFiles Discussion
Topic: pages won't open
Replies: 18
Views: 1540

Re: pages won't open

It certainly seems that any access to viewtopic.php with the 'p' parameter set causes a 500. https://www.spudfiles.com/viewtopic.php?f=6&t=27162 gets me to this thread mostly OK, but https://www.spudfiles.com/viewtopic.php?p=388828#p388828, which should take me to the first post of the thread hard 5...