Trying to choose Face Mask?

[superdank]

Ever since my first successful BP w/ Aluminum rockets started working properly, with drilled core and hotter RP for the drift, I have been absolutely, positively, hooked. I will (hopefully) never have to stop making them, but the more I make, the more a part of my brain keeps reminding me that the odds exist, even if very unlikely, of a CATO occurring during the ramming process, and as soon as the weather isn't so sweaty here, I will start using my welding gloves at all times.

 

It was when I came to thinking about the face mask that I realized the choice of mask will mean everything. I have one of those acrylic face shields, and thought of it first, but then I thought back to some of my first rockets that I video'd during cato, and even with a 5/8 tube, with end-burning fuel during CATO obviously has more than enough energy to imbed peices of acrylic..... well... you know....

 

SO... I have been thinking maybe there are good safety glasses for chemistry (CHM111 next semester or something that are affordable, and wont shatter, or a good brand of safety equipment like goggles or masks that probably wont shatter. As far as the welding gloves, I think I pretty much acknowledge that this hobby runs the risk of blowing a nice pair of welding gloves into shreds.

 

Again, I wasn't worried about ramming BP and other safe comps at all at first, and even after a semi-ugly accident that I had with dark mgal, I still never worried much about ramming (I do like to gamble I suppose) but as the batches of rockets have come and gone, I seem to get a little more uneasy each time. I want to at least protect my eyes.

[mike_au]

I don't have anything to back it up, but to me a decent pair of goggles seem tougher than any glasses I have found. Goggles will also help kept dust out of your eyes which is always nice when working with metal powders. I would suggest that you keep your face mask on as well, the more layers the better.

 

Have you considered getting a press and proper tooling? Ramming and drilling (esp. when your comp contains metal powders) is much more risky. It is also relatively easy to fit a blast shield to a press, something that is a bit hard to setup when ramming. I believe pressing also gives a slight performance boost.

[superdank]

About six months ago I made a press with some threaded rods, steel, and a small hydraulic cylinder. I have mainly used it for fountains so far.

 

http://i25.photobucket.com/albums/c87/gimmeabone/IMG_0358.jpg

 

I prefer ramming because it is much faster, and when I did try a couple of small rockets, the cases would bend a bit, seemingly because my cylinder and the casing were slightly at an angle.

 

I was thinking maybe there is a good kind of face-shield around, and maybe other good ideas

 

Edit: I use Al rods for rammers, so I suppose in theory ramming should be fairly safe

Edited August 18, 2008 by superdank

[superdank]

This is what I mean about even small casings going CATO:

 

http://s25.photobucket.com/albums/c87/gimm...ent=taunted.flv

[FrankRizzo]

Dank,

 

Your casings bent because of the way your press is designed. The threaded rod is very strong in tension, but it easily bends from side-to-side under pressure. You need to attach something to the front or back of the assembly (preferably a blast shield) to prevent the rods from bending toward or away from you during pressing. You'll notice that in Dan William's design, there is a very thick polycarbonate shield attached to the front. That shield is dual purpose, adding a degree of safety plus rigidity to the press.

 

 

http://fogoforum.us/img/press/press009a.jpg

Edited August 21, 2008 by FrankRizzo

[Miech]

Dark Magnalium; Even in Slow Burning Mixes, is EXTREMELY DANGEROUS.

Take it from me, it happened, and I am lucky it wasn't worse. MgAl X BN RP Comp ignitable via slight friction. Beware.

I suppose that means something like barium nitrate with red phosphorus and magnalium? I would rather expect the accident because of the red phosphorus, since it sensitizes mixtures in an extreme manner. I do not intend to say magnalium is a safe compound though.

 

For a face shield, I would think polycarbonate would be the best. It is used in almost every impact proof lab glasses I've ever seen, and it should be sufficient fire and blast proof. It doesn't shatter on impact as far as I know.

[tentacles]

Probably dark MgAl with just about any oxidizer is very dangerous, given the sharp shard shapes of MgAl. I'd think the reactivity would be especially high with nitrates, as MgAl has the reactivity to oxidizers of both Al and Mg, though it is less reactive than straight Mg.

 

Needless to say, you should start scrounging for a hydraulic press components. Dig around, ask around, you can find hydraulic pumps for the taking a lot of times. Try a wrecking yard, look for parting out of trucks with lift gates, or tow trucks, they will have power packs. Cylinders aren't tough to get, and you can just take the hoses off of whatever you take the pump off of. It will change the way you make rockets, I guarantee. Frank was telling me they made 30 rockets in a day at PGI - and had time for other things too, like eating, and the public display.

[superdank]

Dank,

 

Your casings bent because of the way your press is designed. The threaded rod is very strong in tension, but it easily bends from side-to-side under pressure. You need to attach something to the front or back of the assembly (preferably a blast shield) to prevent the rods from bending toward or away from you during pressing. You'll notice that in Dan William's design, there is a very thick polycarbonate shield attached to the front. That shield is dual purpose, adding a degree of safety plus rigidity to the press.

 

Veeeery Interesting

 

I had never looked at it that way, I usually don't get any problems from 1" casings, but I think I see how the rods could warp, I may just have to try that