dangerousamateur Posted July 14, 2012 Posted July 14, 2012 If you had the choice of material, what whould you choose? steel spindle and steel rammers or steel spindle and aluminium rammers? Is it problematic to use a steel rammer on a steel spindle, sparks ect? Or just paranoia?
graumann Posted July 14, 2012 Posted July 14, 2012 (edited) no steel, no steel anywhere. Brass or aluminium. Edited July 14, 2012 by graumann
dangerousamateur Posted July 14, 2012 Author Posted July 14, 2012 Well, there ARE some commercial tooling sets with steel spindles... Why would they do that if it's dangerous?Only they use aluminium rammer on them. So this combinations seems to be safe...? Steel on steel would make me nervous too - but maybe this depends on the type of steel... Is it necessarily unsafe?
WSM Posted July 14, 2012 Posted July 14, 2012 If you had the choice of material, what whould you choose? steel spindle and steel rammers or steel spindle and aluminium rammers?Is it problematic to use a steel rammer on a steel spindle, sparks ect? Or just paranoia? A steel spindle would be okay with aluminum or brass rammers (and they're my preference). The main problem with a steel spindle is that the steel would be eaten by the nitrates if any moisture is present (even atmospheric) and the user weren't careful to clean it well (and oil it) after every use! A brass spindle would work very well. Brass spindles plated with hard chrome would last a very long time (up to ten years of daily use in industry). A steel spindle with steel drifts sounds like an accident waiting to happen (not if, but when it goes bad!!!) The only steel I use for spindles is 300 series stainless steel (non-magnetic, non-sparking). Safety First! WSM
dangerousamateur Posted July 16, 2012 Author Posted July 16, 2012 The main problem with a steel spindle is that the steel would be eaten by the nitrates if any moisture is present (even atmospheric) and the user weren't careful to clean it well (and oil it) after every use!Is it THAT severe in practice?I mean, usually my BP is of course dry, otherwise i would not use it... Not exsiccator dry but air dry... After use I would wash it with water & rub it with WD40 or something...
Shadowcat1969 Posted July 17, 2012 Posted July 17, 2012 Is it THAT severe in practice?I mean, usually my BP is of course dry, otherwise i would not use it... Not exsiccator dry but air dry... After use I would wash it with water & rub it with WD40 or something... The other issue that I can see with a steel spindle, is that there is possibility for friction between the fuel and spindle when they are separated. Even by using a puller and pulling the spindle straight, there will be a moment at release that, IMO, COULD cause more friction (or chance of spark) than what I would be comfortable with taking as a chance. Even with the most pure chemicals we can find, there is always the chance of getting a tiny bit of contaminant in there inadvertantly that could be spark causing when rubbed on steel. Just my personal opinion on it. I will always stick with Aluminum, Brass or Stainless Steel.
dagabu Posted July 18, 2012 Posted July 18, 2012 Keep in mind that this issue goes well beyond the issue of friction and any possibility of sparks (do we really think any of is capable of causing a spark by pulling out the spindle?), the larger issue in my mind is the inability of steel to be smooth, or at least as smooth as stainless, aluminum, brass etc. Under a scanning electron microscope, you will see the crystallization of all the metals listed above and you will see that steel is dreadfully hard to put a "shine" on while stainless has a lattice work and aluminum has a relatively flat plain. The last concern is the concern of corrosion and the destruction it causes in short order on spindles. I have several old (now 25 years plus) spindles made from grade 8 bolts that when oiled, held up remarkably well over the years but were a complete bitch to pull out of the finished rocket while brass almost falls out... -dag
Col Posted July 25, 2012 Posted July 25, 2012 I use brass for spindles and rammers, T-6 Alu is ok but it doesnt seem quite as rigid or as slick as polished brass. Stainless is the best for tube rolling mandrels. Dag, If you want a brass spindle to fall out, give it a final buff with the slightest hint of silicone grease (servisol) on the cloth.
dagabu Posted July 25, 2012 Posted July 25, 2012 I use brass for spindles and rammers, T-6 Alu is ok but it doesnt seem quite as rigid or as slick as polished brass. Stainless is the best for tube rolling mandrels. Dag, If you want a brass spindle to fall out, give it a final buff with the slightest hint of silicone grease (servisol) on the cloth. I use Jig-a-Loo (dry silicone) since I found silicone grease to inhibit the core burn slightly. We don't have Servisol here in the US, Marvey's has it in a 14.7mL tub for $1.99 US at the Home Depot and is the same item. With a fast whistle, you don't notice but with a marginally slow BP fuel, it is a bit too much. I do agree with the use of it for Salicylate whistle rockets, they are really sticky. A bit of Marvey's on a Q-tip spread out inside the rammers helps with cleaning too. Thanks for the hint Col. -dag
Col Posted July 26, 2012 Posted July 26, 2012 We dont have Jig-a-Loo here so i guess it all balances out Here`s another tip, for the final buffing use dry crumpled up newspaper.. Its also very good for getting the initial residue off a brass spindle before you use the polish.
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