pyrothrust Posted December 18, 2011 Posted December 18, 2011 When you've had a rocket motor go bang while hand ramming, you give up on this pretty damn quick, unless your lacking in cells. I had protection on a 3# BP motor ( which I have probaly made over 200) when a bit of fuel pinched on the top of the spindle. and of she went , upwards ,sideways with one heck of a lot of smoke. Other than ringing ears I can joke about it. The googles and gloves saved me luck did the rest. and shit I was being careful, Never hand rammed a motor since. and since going hydraulic the consistency is far better than any hand ramming.
dagabu Posted December 18, 2011 Posted December 18, 2011 When you've had a rocket motor go bang while hand ramming, you give up on this pretty damn quick, unless your lacking in cells. I had protection on a 3# BP motor ( which I have probaly made over 200) when a bit of fuel pinched on the top of the spindle. and of she went , upwards ,sideways with one heck of a lot of smoke. Other than ringing ears I can joke about it. The googles and gloves saved me luck did the rest. and shit I was being careful, Never hand rammed a motor since. and since going hydraulic the consistency is far better than any hand ramming. Double Amen! I only pound 1/2" and smaller rockets and have two arbor presses plus a hydraulic press to handle anything I might need pressed. -dag
allrocketspsl Posted December 18, 2011 Posted December 18, 2011 When you've had a rocket motor go bang while hand ramming, you give up on this pretty damn quick, unless your lacking in cells. I had protection on a 3# BP motor ( which I have probaly made over 200) when a bit of fuel pinched on the top of the spindle. and of she went , upwards ,sideways with one heck of a lot of smoke. Other than ringing ears I can joke about it. The googles and gloves saved me luck did the rest. and shit I was being careful, Never hand rammed a motor since. and since going hydraulic the consistency is far better than any hand ramming. any metal in the comp?
pyrothrust Posted December 19, 2011 Posted December 19, 2011 (edited) No metal in the mix just a reasonable slowish not too hot BP for this size motor, I did not stike the spindle as I was already at the top of the spindle and had just gone to a solid ram with a 3/4 ID raise above the sindle Edited December 19, 2011 by pyrothrust
firebird Posted December 19, 2011 Posted December 19, 2011 No metal in the mix just a reasonable slowish not too hot BP for this size motor, I did not stike the spindle as I was already at the top of the spindle and had just gone to a solid ram with a 3/4 ID raise above the sindle Now you have me curious . You were a full increment above the spindle? Did it happen on a strike or when you were removing the drift? We have seen on 2 occasions where removing the drift may have caused problems . I also have had one go in my hands very very early on . It was my fault. Thank God it was a cheap lesson. Second degree burns to 3 fingers and a little on the hands. Grabbed the wrong drift lesson learned ( I hope ) One thing to remember IF- When you stick a drift . STOP do not try to un-stick it with force. Put it in water swallow your pride and let it soak. We all stick drifts even the best have and still do it on occasion. So don't jump on the high horse it happens. I am not saying this is what happened to you but I am very curious about your incident . The more we know about the hows and why's the better we are at prevention.
dagabu Posted December 19, 2011 Posted December 19, 2011 Now you have me curious . You were a full increment above the spindle? Did it happen on a strike or when you were removing the drift? We have seen on 2 occasions where removing the drift may have caused problems . I also have had one go in my hands very very early on . It was my fault. Thank God it was a cheap lesson. Second degree burns to 3 fingers and a little on the hands. Grabbed the wrong drift lesson learned ( I hope ) One thing to remember IF- When you stick a drift . STOP do not try to un-stick it with force. Put it in water swallow your pride and let it soak. We all stick drifts even the best have and still do it on occasion. So don't jump on the high horse it happens. I am not saying this is what happened to you but I am very curious about your incident . The more we know about the hows and why's the better we are at prevention. If I may add a little? Twisting the rammer and twisting the motor on the spindle IMHO is the real culprit when it comes to popping a rocket. I have a habit of only turning a motor on the spindle 1 full turn while lifting up and then I immediately feel if the spindle is warm or not. In some cases, I have found the spindle to be very warm after removing the spindle and I adjusted the pressure down so that it would release easier. If it were possible, I think that an ejector for motors where the finished motor, motor with a jammed spindle or whatnot would take care of almost all the motor popping issues we have seen. The one that happened right between Firebird and I last summer was a real eye opener and had the position of the motor been vertical instead of horizontal as it was, there would have been injury for sure. The conclusion was that it was the twisting that caused the comp to heat and ignite the motor. I had my entire family plus a couple visitors standing no more then 15' from the motor and none of use were injured in any way except for some ear ringing. As Firebird says, Thank God. -dag
Col Posted December 19, 2011 Posted December 19, 2011 I have one thing less to worry about then. My spindle removal method solves most, if not all, of the frictional issues. They pull out easily in a straight line with no twisting even when they are stuck solid.
dan999ification Posted December 20, 2011 Posted December 20, 2011 my new tooling has the same feature, is the bottom of yours threaded or do you press it out? dan.
Col Posted December 20, 2011 Posted December 20, 2011 Its internally threaded Dan, the entire spindle pulls straight down through the base using a nut and a stack of M20 washers on the threaded rod from an old G-clamp.
dan999ification Posted December 20, 2011 Posted December 20, 2011 Its internally threaded Dan, the entire spindle pulls straight down through the base using a nut and a stack of M20 washers on the threaded rod from an old G-clamp. snap . dan.
Mumbles Posted December 20, 2011 Posted December 20, 2011 Not to kill your sense of ease, but this did start out as a discussion of removing the rammers/drifts, not the spindle. I do agree that every little part helps though. A good way to remove a spindle is just one less thing to worry about. Another thing I like that I've seen in certain places is dedicated wooden boxes for each set of tooling or identifying markings. When everything is jumbled together, or gets accidentally mixed, grabbing the wrong rammer can lead to poor endings. A stuck spindle is no fun, which is probably the least of your worries.
dan999ification Posted December 20, 2011 Posted December 20, 2011 we need internally threaded drifts . dan.
dagabu Posted December 20, 2011 Posted December 20, 2011 Not to kill your sense of ease, but this did start out as a discussion of removing the rammers/drifts, not the spindle. I do agree that every little part helps though. A good way to remove a spindle is just one less thing to worry about. Another thing I like that I've seen in certain places is dedicated wooden boxes for each set of tooling or identifying markings. When everything is jumbled together, or gets accidentally mixed, grabbing the wrong rammer can lead to poor endings. A stuck spindle is no fun, which is probably the least of your worries. Agreed, I have a wood block with holes drilled in them the size of the rammers so there is no mistaking one for another and I will be transitioning to boxing them up as well since they are less likely to be damaged. -dag
Col Posted December 21, 2011 Posted December 21, 2011 Not to kill your sense of ease, but this did start out as a discussion of removing the rammers/drifts, not the spindle. I do agree that every little part helps though. A good way to remove a spindle is just one less thing to worry about. Another thing I like that I've seen in certain places is dedicated wooden boxes for each set of tooling or identifying markings. When everything is jumbled together, or gets accidentally mixed, grabbing the wrong rammer can lead to poor endings. A stuck spindle is no fun, which is probably the least of your worries. I have a habit of wandering off topic..apologies for that It wouldnt be too difficult to make a puller that can utilise the tee bar hole at the top of the drift. The no pass line should provide at least 1/2" of space to work with. Drilling and tapping a hole would be easier given the choice, depending whether you want to drill a hole in expensive tooling The parts would be cheap, a length of steel tube, a few washers, some threaded rod and a nut . Of course Its better not to get the drift stuck in the first place but when (not if) it happens it`d be nice to have a safe way of shifting it even if it took a bit longer than the twist and pull method.
Mumbles Posted December 21, 2011 Posted December 21, 2011 If you ever really stick a spindle don't get brave and try to pull it out no matter what sort of contraption you've devised. It's better to swallow your pride, soak the whole thing and disassemble it. You'll still have metal on metal contact no matter how it's removed.
Col Posted December 21, 2011 Posted December 21, 2011 (edited) you got me confused now was that spindle or drift?I was thinking along the lines of a basic stuck drift where the comp has crept up between the spindle and the hollow drift. The risk of removing the drift is mainly in the friction If its stuck due to accidently using the wrong drift then the bucket of water would be the best plan, assuming you realised you`d used the wrong drift I only have one set of drifts per id so its not much of an issue but i imagine it could happen quite easily where there`s a bigger choice of tooling. Edited December 21, 2011 by Col
Mumbles Posted December 21, 2011 Posted December 21, 2011 Shoot. I got me confused too What I was talking about is sticking a drift onto a spindle. This is pretty rare, but can and does happen. Most instances I hear of happen when rammers get mixed up. IE if you use a BP rammer by accident on a Universal/Hybrid set, there is the possibility to get them stuck as the U/H spindle is wider than BP. It also happens from time to time when fuel (whistle especially), gets up between the spindle and drift, and sort of gets sandwiched. That is one of those cases where twisting would be bad, but a direct puller may not be so harsh on it.
dagabu Posted December 21, 2011 Posted December 21, 2011 Both are correct semantically. In the USA, the tern spindle has been associated with rocket cores while the UK has used the term drift. The term drift comes from early crude rocket making where a drift pin was used to form the tapered hole in the core of a rocket while a spindle is really a straight pin like that used in an end burner but over time was adopted to mean the same thing as a drift. The term nipple was then used to explain the short spindle of an end burner in the USA and has been pretty well accepted as such. -dag
Col Posted December 21, 2011 Posted December 21, 2011 (edited) I don`t think i`d want to take any chances with a drift stuck in a whistle motor, twist or no twist it would be going in the bucket Edited December 21, 2011 by Col
pyrothrust Posted December 25, 2011 Posted December 25, 2011 Rebuilt my whistle spindle and base so that the spindle removes from the base easy. I then drilled and taped the spindle internally so that I can know use a threaded rod and an alloy spacer to remove the spindle by tighting up a nut and it works a treat now very easy to remove . I was beginning to get worried about how tight the sindle is on these motors and was never able to pull them out other than by twisting the base back and forth which was scary.
Col Posted December 25, 2011 Posted December 25, 2011 Its surprisngly easy it is to shift the spindle using the internal thread, rod, nut method. I`m sure it`ll be adopted by commercial rocket tool makers before long.
nater Posted December 25, 2011 Posted December 25, 2011 Wolter and Firesmith both provide easy means to pull the spindle off thr motor. They attach the spindle to the base differently, so the means are different, but both are effective.
Col Posted December 31, 2011 Posted December 31, 2011 Hi nater, i haven`t seen any of the commercial tooling up close so i didn`t really know what method they used I pressed a few 3/4" motors for nye today and they all came off the spindle without any drama.http://i770.photobucket.com/albums/xx341/colinspyro/2011/nyerocketmotors.jpg
nater Posted December 31, 2011 Posted December 31, 2011 Do you rub a little graphite on your spindle before pressing? I bought some recently to try to see if that helps the motors release easier on my next batch.
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