ballmill Posted February 18, 2011 Posted February 18, 2011 I used http://www.flashnet.dk/rts/ to get dimensions for a set of 1 lb rocket tooling and started turning the spindle on the lathe. I used a taper attachment for the 1.25 degree taper however it appears it must have been off. I ended up with my correct .130 diameter and the end of the spindle but near the bottom it is about .340, much smaller than the actual .375 it was supposed to be. Being completely new to black powder rocket design, how much performance am I going to lose? I also realize I'm going to have to modify the hole sizes for my rammers. Maybe it would be best to start over at this point.
dagabu Posted February 18, 2011 Posted February 18, 2011 You are cool, just add 1-2% more charcoal to cool the burn. If it CATOs, add 1-2% more charcoal. Go slow but the nozzle is still in the OK range. Congrats on the new tooling
ballmill Posted February 18, 2011 Author Posted February 18, 2011 You are cool, just add 1-2% more charcoal to cool the burn. If it CATOs, add 1-2% more charcoal. Go slow but the nozzle is still in the OK range. Congrats on the new tooling Thanks! Hey, did you get my PM about your tubes for sale? If you still have some, I'm interested.
dagabu Posted February 18, 2011 Posted February 18, 2011 Yes, sorry, I have been a little overwhelmed with spring coming. Hang in there and I will get to it. Email me, K?
millhouse Posted October 2, 2011 Posted October 2, 2011 Ok now,i also have a question. I bought everything for my tooling. Now my question is - how do you drill the rammer hole without a drill stand? I mean have anyone got any ideas for drilling a straight hole with a cordless drill?Another thing is what ID nozzle should i make for a 16mm ID tube? I think something about 8mm should be just ok for a core burnner?
Mortartube Posted October 2, 2011 Posted October 2, 2011 I use an 8mm choke in my core burners and a 3mm choke in my endburners with a 16mm I.D
millhouse Posted October 2, 2011 Posted October 2, 2011 Cheers, also,what BP ratio ar you using for this tooling?
WonderBoy Posted October 2, 2011 Posted October 2, 2011 (edited) Here is a good page about making tooling by Dan T, he outlines a good way to drill the center of the ram: http://pyrodan.privatedata.com/fireworks/nozzleless.htm Edited October 3, 2011 by WonderBoy
Mortartube Posted October 2, 2011 Posted October 2, 2011 (edited) My core burners use unmilled willow BP in these ratios. It is all sieved to the consistency of talcum powder. I have homemade sieves so haven't an accurate mesh size. KNO3 68% Sulphur 14% Charcoal (AF) 18% My end burners use the usual 75/10/15 Kno3/S/C BP which has willow charcoal and is riced with + 5% dextrin. This is milled for 10 hours in a rock tumbler. Edited October 2, 2011 by Mortartube
guntoteninfadel Posted October 3, 2011 Posted October 3, 2011 Ok now,i also have a question. I bought everything for my tooling. Now my question is - how do you drill the rammer hole without a drill stand? I mean have anyone got any ideas for drilling a straight hole with a cordless drill? What material are you making the Rammers out of? Even if you were making them out of wood it is going to be more than a little difficult with a cordless. A drill press would be doable but difficult at best. Nighthawkinlight had some way of boring those holes and he is a preverbal genius when it comes to accomplishing the impossible. I'm sure he will see this post and reply. If it were me I would find someone with a lathe. The charge should be less than lunch money and the results would be far better than off center and un plumb(crooked)!
dagabu Posted October 3, 2011 Posted October 3, 2011 (edited) Ok now,i also have a question. I bought everything for my tooling. Now my question is - how do you drill the rammer hole without a drill stand? I mean have anyone got any ideas for drilling a straight hole with a cordless drill?Another thing is what ID nozzle should i make for a 16mm ID tube? I think something about 8mm should be just ok for a core burnner? Making a centered hole in wood is easy. First, take the dowel and set it on the edge of a flat surface like a table and with about 1" overhanging the edge, roll it for several inches back and forth. Look closely at the end when you see the center that hardly turns, mark it with a pin or tack. Hold the pin or tack in the center and roll the dowel back and forth, if the pin or tack feels like it is centered, without wobbling, then you are ready to move on the the next step. Now take a small drill bit, perhaps 1/8" and chuck it up in a hand drill (powered) and put that bit where you made the mark with the pin or tack. Drill in about 1/8" and then lay the dowel back on the table. TRICKY PART!! With the dowel slowly rolling, drill the 1/8" bit all the way down into the dowel, you will feel if the bit is straight or not as it will wobble. Move up the the size drill bit you need for the rammer and following the same roll-&-drill routine, drill the larger hole. When you are done, you should have a perfectly centered hole. Also, 8mm is the right nozzle size for a BP spindle using a 16mm tube. -dag Edited October 3, 2011 by dagabu
millhouse Posted October 3, 2011 Posted October 3, 2011 Thank you guys,i will try these mentioned methods. My rammers are going to be wooden.
dan999ification Posted October 6, 2011 Posted October 6, 2011 (edited) i struck lucky with making the base and spindle first, put a tube on it insert the rammer and give it a tap this should leave a mark at centre, then a tube in a tube in a tube was used over the rammer to centre the drill similar to the washer method i suppose,i used a 9v cordless and al, even drilled the base and inserted brass rod spindle, starting with a bit that is smaller than you need may help as i found there was some minimal movement enlarging the hole this way, go in a bit offer it to the spindle and go again bit by bitpics to follow, finished them in an afternoon with minimal tools [hacksaw blade, 2 files, 2 drill bits, 120, 400, 600, 1200 paper to polish]dont know what i was scared of and that i was actually gonna pay for something so simple to make even for me. dan.edit they work on the ground test the first flight will be finned Edited October 6, 2011 by dan999ification
millhouse Posted October 15, 2011 Posted October 15, 2011 Ok. Tryed many methods,but this method shown on Dan's page worked the best. Although better results were achieved when i turned the rammer and held the drillbit in place,instead of drilling with a drillbit spinning. Ah,you know what i mean. Today i finally made some 16mm rockets with a 8mm nozzle and 6mm core. They worked pretty well, despite what the BP i used was 2 or 3 years old and kind of too slow. Anyways,i am planning to invest some more money and make a pro tooling for 16,25 and 35mm rockets, on a normal lathe. Anyone got any plans? Thanks in advance guys!
guntoteninfadel Posted October 16, 2011 Posted October 16, 2011 The profile Dag uses works well and you really have to have some HOT bp to cato. Its not his original as I understand but he might email you the specs.
millhouse Posted October 18, 2011 Posted October 18, 2011 Guys i wanted to know how much can your rockets lift?For example,lets take 16mm ID rockets. I tested mine,using standart BP ratio and 8mm choke for a core burnner and it lifted 70gr pretty easy. How much can a 16mmd end burnner with a 3mm choke can lift?
dan999ification Posted October 18, 2011 Posted October 18, 2011 Guys i wanted to know how much can your rockets lift?For example,lets take 16mm ID rockets. I tested mine,using standart BP ratio and 8mm choke for a core burnner and it lifted 70gr pretty easy. How much can a 16mmd end burnner with a 3mm choke can lift? 10mm id 2.5mm choke is to me a 3 oz rocket it can lift 3 0z thats normally a 30-35g payload the stick and motor make up for the rest,you may need to go bigger on the choke to avoid cato but i would say it should lift 70g payloads 100g ish with the stick and motor.i only base this on the fact that 10mm id is half the surface area of 16mm id. dan.
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