ADA: Ask Doc Anything!

[DocsMachine]

In the interests of having something to talk about, how about an ADA, or Ask Doc Anything?

My areas of expertise are paintball, machine tools and machine work, old musclecar-era cars, some firearms and a little art and graphics, of course. I do not know everything- a lot of you know more minutiae on some specific markers- but I'll answer what I can.

Or if I don't know the answer, I'll make up something funny.

Ask me about the comic, ask me about the shop, ask me about paintball, ask me about the cat, ask me about my car, etc. Fire away!

Doc.

[macaco]

Thanks for coming back Doc!

[DocsMachine]

That's not a question!

(But you're welcome! Wild polar bears couldn't keep me away. )

Doc.

[russc]

For a guy just starting to get a small hobby shop going, what are the essential basics? For reference I've got a CNC Taig with a few sets of 1/4" end mills, and basic Shars 1/2 thou micrometer and calipers.

[snaparen]

more beer.

[Smapdee]

What’s the best time of year to re-seed my lawn?

[Meleager7]

Which guns, montneels and 68-specials excluded, can run on liquid co2?

i had Jordan fabricate a new Siphon tank for me a few months ago for my 68 special( brand new guardian 12oz, NOS siphon kit, scavenged co2 pin valve with no safety groove). And i’m curious what other guns i could try with it?

[MrKittyCatMeowFace]

My air America unireg has bad reg creep and ive decided to replace it with a bob long expansion chamber and rebuild a old agd flatline reg i have to run in the uni's place.

my question to doc would be what to set the output pressure at on the reg. or to put it better, how to tune my cocker so i blow it up.

[Siress]

This is stupidly broad and probably too difficult to answer, but I've always wondered on some level: What's it like living in Alaska?

Where can I find a lathe this small or smaller with the same functionality and rigid enough for 6061-T6?

[Carp]

If you had to be both, punched in the face and kick in the nuts, which order would you like to receive them? ie...face then nuts or nuts then face?

[DocsMachine]

For a guy just starting to get a small hobby shop going, what are the essential basics? For reference I've got a CNC Taig with a few sets of 1/4" end mills, and basic Shars 1/2 thou micrometer and calipers.

-That's actually a really good start. Just keep in mind the Taig is a pretty light machine, and can't "hog" metal off like... well, virtually anything else.

I'm assuming the Taig likely has the ER collet nose- grab a decent-quality set of matching collets (if you don't already have some) and a selection of various size endmills.1/4" shank is about the most the typical Taig should try to handle, but you can get other sizes of cutter like 1/16", 1/8", 3/16", etc. Since it's a CNC, if you'll be playing with 3D contouring, grab some 1/8" ball-end mills.

Do NOT buy the cheapest thing eBay has. You WILL get junk. Pay a bit extra for either name brand or from a reputable dealer- LMS, Shars, maybe, etc. If it comes in an "E-packet from China", you stand a very good chance of getting junk.

What do you have for a vise? Typically people will plunk a "screwless" vise on there, and that's not a bad option, but LMS has a proper vise with a screw which will be a LOT easier to use.

Don't worry too much to start with, with the micrometer- especially one that reads in half a thou. You'll wind up chasing your tail and fretting over thousandths. Grab a good quality digital caliper- a name brand like Fowler or Mitutoyo, it's worth spending the money- and don't worry when anyone tells you they're "not accurate enough". You're using a desktop, aluminum-framed machine to make paintball parts. You're not making aerospace rocket-engine bits, most times you can be within .003 to .005 and the part will will still work just fine.

What else... spend a couple bucks buying dedicated tools. That is, if you need allen wrenches, open-end wrenches or a spin spanner or something to regularly use the machine, buy spares so you can specifically leave those with the machine. You're not always going back to a toolbox or rummaging through a drawer to find them- plus you have spares. If the dedicated one goes missing- and it will- you have a backup in the regular tool box.

And of course with the CNC- learn your speeds and feeds. There's a LOT of Taig and Taig CNC users out there, and most of them have learned just what the machine is capable of. Pay attention, a proper chipload helps the cutter last longer, improves surface finish, reduces potential breakage, etc. Don't push it just to get the part done faster.

Hopefully that'll get'cha started.

Doc.

[DocsMachine]

What’s the best time of year to re-seed my lawn?

-Towards the fall. The seeds have a chance to germinate before going dormant for the winter, and also don't have to compete with as many weeds.

Doc.

[DocsMachine]

Which guns, montneels and 68-specials excluded, can run on liquid co2?

i had Jordan fabricate a new Siphon tank for me a few months ago for my 68 special( brand new guardian 12oz, NOS siphon kit, scavenged co2 pin valve with no safety groove). And i’m curious what other guns i could try with it?

-Almost all Nelson-based pumps can handle it pretty easily, the problem is usually getting it "charged" in the first place.

The thing is, while most unregulated blowbacks can handle liquid CO2, none are really designed for it. The primary issue is the chamber volume- the IconZ and SMG/68-Specials, had pretty small valve chambers, which is in part why they had to run liquid in the first place.

Most other markers have much larger valve chambers, intended to run gaseous CO2, or of course HPA. You can feed 'em liquid, but you'll generally go way over velocity, and have atrocious gas consumption.

You could take something like a typical Spyder clone, and fab up some sort of "devolumizer", kind of like people have made for WGP-based pumps, when running 12-grams.

Apart from that, there's not much. VM-68s, of course, Sheridan pumps and older Snipers (early models would be the best) maybe the early Illustrators, etc.

Doc.

[DocsMachine]

My air America unireg has bad reg creep and ive decided to replace it with a bob long expansion chamber and rebuild a old agd flatline reg i have to run in the uni's place.

-The Unireg is an inline, goes on the gun. The Flatline is a supply tank. Two different things. I like the Flatline, though they're getting old enough it's time to seriously check the O-rings before airing it up, and I'm not sure I'd run it as the primary regulator for the gun.

The UniReg is dirt simple, your creep is almost certainly due to an old main seal, or possibly- though less likely- a scored primary valve cup. I'm told somebody is making replacement seals, grab one of those and see if the creep goes away.

my question to doc would be what to set the output pressure at on the reg. or to put it better, how to tune my cocker so i blow it up.

-Kind of too open ended. That's like asking "how do I improve my car's performance". Well, there's lots of ways, but the same stuff that's going to work on a '68 VW Super Beetle isn't going to work on a 2020 Dodge Charger Hellcat Redeye.

However, the common trick is to "sweet spot" the gun. Set the tank (if it can be set) to about 800 psi, and then set your inline reg low- to the point the gun clearly has low velocity, but still fires. Shoot it over the chronograph as you incrememtally, and slowly, raise the pressure. You'll find a spot where raising the pressure more stops giving you more velocity. This is your "sweet spot".

If you have too much velocity, turn the spring adjuster down, or swap to a lighter spring. If your velocity is too low, crank up the adjuster a bit or swap to a stiffer spring.

That's a VERY simplified and basic description- you'll have to keep playing with the LPR pressure to keep the gun cycling as you do this, and this really doesn't address springing for best efficiency, but it'll at least get you started.

Doc.

[MrKittyCatMeowFace]

Thanks doc for the info. I didn't know someone was making new seals for the unireg, thats cool! Think im still gonna do the flatline (would rather it be a center flag). I know that the flatline goes on the tank. What i meant to sat was the expansion chamber would go in the uni's place. Just as a grip you know instead of having just a bottom line (And more bob long parts on it). I saw agd website sells everything for the flatline still so im in luck because it really needs a complete rebuild. Tank is at 850psi so were close.

[Tracker]

can you drill and tap a half block pump arm to 4-40 for an A/T pin for me? for... science

[DocsMachine]

This is stupidly broad and probably too difficult to answer, but I've always wondered on some level: What's it like living in Alaska?

-I both love it and hate it.

I'm not a "big city" guy, I prefer small-town living. I know my business would likely be a lot better if I were based in, like, LA or Dallas or Boston or something, but I prefer the small-town life. Summertime weather is great- right now, "night time" is about an hour long and even then still isn't fully dark-dark.

The flip side of that is that honestly, summer only lasts about three months. June, July and August. There's still plenty of snow on the ground in April, May is usually still muddy and nothing's green 'til the end of the month, and by September, it's cold and rainy and the leaves are falling off the trees. Statistically speaking, we'll have our first snow by mid-October.

Right now, you couldn't entice me away with a stack of cash and a naked supermodel. (Okay, maybe just the cash... ) but in the middle of winter, when it's dark dark from literally 5 PM to 9:30 AM? If you told me you had a small slice of cheesecake, I'd walk to the airport and hock a kidney to fly down to get it.

Where can I find a lathe this small or smaller with the same functionality and rigid enough for 6061-T6?

-Good luck. Virtually no small lathe has a turret. The closest you'll find is something like an EMCO Compact 5, but those have thoroughly antiquated software and drivers, meaning you'll have to do a nontrivial upgrade to make it work. They're also popular with home-shop types looking for the same thing, and so go for stupid money even in parts.

Even disregarding the turret, your choices are slim, Taig or Sherline, maybe, or a converted desktop import.

Doc.