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Ironduck

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  1. I'm comming late in reading and now posting to this thread, and it is tempting to let the dog lie but in the oft chance that someone is still considering the OP I shall offer the following assessment. For me it has been both an interesting and disapointing thread to read. So many knowledgable Smiths in regards to methods that have worked for them, both in practice and in teaching settings, but I'm not sure that many were listening to each other or staying on the topic or kernal of the OP. Brian didn't help his cause much during his opening proposal or his early attempts to convey motivation of the same. I usually find Brian very good at explanations, but he failed to explain clearly what was deficient about the weld or the teaching method, and worse yet, failed to offer suggestions, early on before the emotions surfaced, as to how to mitigate the weld's shortcommings or a better method of accomplishing the weld. You made several attempts, but each was late in the game and at that point emotions seemed to be surfacing by all. Now if the weld was taught with a purpose and as a means of both building confidence and rudimentarily showing a simple forge weld, then I think all is well and good. But while the glow of success is still bright (during that teaching session) there needs also be an explanation or demonstration as to what the weld or method deficiencies are so that the student understands what to look for in a weld, and furthermore gives the student cause to consider what is going on near and at the boundaries of the joint so they can better choose jointery methods or preparation. Is this done in classes coving forge welding, I don't know. But it should be, otherwise the learning experience is more than just lacking. IMO kudos go to Anvil for his understanding of the OP and his methodlogical explanation of how to achieve a proper (translation: as near complete weld with most importantly, no loss of cross-sectional area at the weld or adjecent to it). Unfortunately others continued talking about end use, completely missing premise of the OP (poorly presented as it was I still understood that Brian wsa concerned about x-sectional area preservation as much as fusion along the boundaries. Now, I am not a disciple of any of the smiths that post on this or any other forum, though it would be a disservice to say that I haven't learned a good deal from each, herein or at demos. As was said more than once in this thread there was "a failure to communicate."
  2. Ironduck

    forge

    interesting design. With all the air currents flowing under, and cooling, your forge shelf, does the chamber get very hot (all things being realitive)?
  3. Ironduck

    Tongs with an attitude

    Too beautiful to use - definitely a display piece.
  4. Ironduck

    5# of 1095

    OD, I'm shocked that none of the experienced Smiths on this site haven't commented about your choice in metal. Do you really dislike your anvil that much that you'd use 95pt carbon steel on it? (a good bit higher concentration than is warranted - 45pt might be a better and safer steel.) You should always want your hammer a bit softer than your anvil (a hammer is a good deal less expensive to replace or repair than an anvil). Hopefully someone PM'd you, but that doesn't help the other new smiths that might see this chunk of steel and think that it's OK. You asked for advice, so that is my contribution (find some 1045 for your first hammer - also a tad bit easier to forge than 1095).
  5. Ironduck

    Mystery tool

    Ben Smith is the closest to being on mark. They were used by linemen to twist hard drawn copper overhead lines (making what was known in the 40s, and there about, as a Westinghouse splice). You needed two sets of the "crimpers", as shown, with a proper space between them and then they were rotated about the axis of the wires that were placed in adjacent parallel grooves. Some time during the 50s it became common to place the wires in a copper sleeve first and them twisting the bundle.
  6. Peter, Thanks for your interest in my optimization of JasonM's original post. I don't have any dimensioned drawings for the entire treadle hammer, except for the free-body diagrams of the Hoecken's mechanism, as the rest of the treadle hammer would need to be sized according to the user. (I'm 6'-2" tall and what would be comfortable for me for the type of use I would want for this hammer might not fit the needs of most others). The wooden prototype that I threw together was aproximately 1/2 scale, and was mostly just cut on the fly - no drawing for the frame (only the Hoecken's mechanism). As in the PM I sent you, I will look about my boxes some time over the next two weeks and dig out these drawings and calculations and forward to you what might be useable or readable (I tend to do a lot of margin scribling and doodling on my drawings while I'm thinking, so I'll probaly not send much of that). But If I recall most, if not all, of the critical size ratios for the linkage is shown in one or two of the pictures I inserted in my original post. Tubbe, I'd be interested in what the arm and linkage ratios were that you used (Maybe I'll try to scale them off your lego mock-up). Placement of the ram pivot points in front of the ram would make for a more compact hammer mechanism, but the drive link operating within the space of the throat (space between the ram, or anvil, and the column) reduces again your available working space if one where workiing a larger piece. (it's all a trade-off no matter how it is designed). I'll be interested in doing some calcuations to see if your optimization of the linkages maintains as straight a line as the Hoecken's. At first glance I like what you did, but I fear that the change in geometry and pivot rotation points will cause some front to back oscillations. What was your expected ram travel for a specified arm length? -Charlie
  7.     Daniel, I'm a bit late to the parade, there's been a good deal of deserved encouragement and positive feedback given by others, but I'd like to offer some unsolicited recommendations. Now please don't take any of this negatively. You're young and show tremendous talent (you tongs are well made), so this is all the more reason that it would be a crime if you were to leave the craft prematurely due to frustration, fatigue, or injury (I mention that only because you seem really tense in the film - relax your shoulders and breath naturally). Now for the benefit of others, digital cameras are notorious for showing hot metal as being hotter than it really is, so my first suggestion is to let that beefy chunk of metal soak up some more heat and reheat it long before it gets to cherry red (that's likely what it was when the video showed orange). You'll find the metal moves easier and you don't have to work as hard (more on that shortly). A good example of what I'm talking about is at 3:26 into the clip - you'll notice the outer surface of the metal is moving lengthwise but the center is not keeping up (that's one of the reasons for the spikes at the end of your stem). I realize that tapered stems are all the craze, and I'm not going to comment on their time or place, but what you desperately need is a set of butchers, a set tool, and someone competent to strike for you when you are trying to move stock that size. Making bottom tools out of 1-1/2" stock on a 100kg anvil with a 1.5kg hammer without someone striking is boarder-line madness. The persistence that you show is commendable, but we should be working smarter not harder - the craft is more enjoyable if you're not beating yourself up at the anvil. Besides, you've got to make that arm, and all its joints, last a long time yet. (I won't belabor this point any further - I've taken off my medical hat.) Otherwise, real nice work. Be the future of the craft. -Charlie
  8. Dale, I'm not sure I know what tongs you are calling "round nose", unless you are talking about farrier's tongs? As for making the jaws on your tongs, always consider their intended function. For example, box jaw tongs made too light or thin will not do well to hold thick material, and conversely rivet tongs made too stout will draw too much heat from the rivet before you get to upset the rivet. Considering that you're just starting and looking for information, I would like to add to the reference that Francis Trez Cole provided, The Blacksmith's Manual, thought slightly off topic, you might be interested in other "free" manuals that were published by The Rural Development Commission (RDC) such as The Blacksmith's Craft, Wrought Iron Gates, and others. You can download PDF versions of these at http://www.hct.ac.uk under the reference or download tab (just can't remember right now). Another good site for information is ABANA or doing a search on the Internet Archive (search for tongs, blacksmith, metal work, etc). Good luck with your hammering, Charlie
  9. Deadlines definitely work for you. Not quite traditional celestial Pisces in layout, but unquestionably elegant in form. -Charlie
  10. Fancy word - well as ciadog already stated: "Door lites", but possibly Door fenestration is more what you were looking for. And regarding the iron work - very nice indeed, and all in eight hours - I trip over too much stuff in my shop to be able to work that quickly.
  11. TubularFab, The candle holders look real good. Your trouble with maintaining uniform pitch could be addressed by instead of curling the rod individually, take two rods (or three rods if you want a really steep pitch) side by side and wrap them simultaneously around your form (pipe, large rod, or some other mandrel) and when you've got the coil length you want just uncoil the rods from each other and finish the ends as necessary. The extra rod (s) will determine the pitch and help in maintaining uniformity in the wrap, and it also means one more gift for someone - Just a thought. -Charlie
  12. Arranged as they are, they're look good - but they might interfere with use of your anvil. ;) Or is that why your wife liked them, so you'd spend more time inside with her.
  13. Dave, Looks nice. I have to second JohnB's suggestion regarding the guide tube for the latch handle - but that would be for your next stove. Also regarding the handle it looks like it will be terminating somewhere in close proximity of the stove's heat surface - maybe it would be better to have had it angled differently and had the handle portion more loosely spaced like that of the old parlor stove lifting handles - better cooling (looks like a tapered coil springs wound around the shaft of the lifter). Overall, nice work. -Charlie Had to go back in and edit my post, which I made before seeing the last of your photos. (just deleted a bit about a impingement or baffle plate. Regarding you draft, how high above the roof line or nearby obstructions is the top of the flue?
  14. That first one is beautiful - real fluid design and finish. She's got an eye for it. Circle CP Forge, nah. Work like that she deserves her own touchmark. -Charlie
  15. The adze looks fine. If you make another one, or more than that matter, you might want to shape the handle eye like that of a pick or mattock (tapered or cone shaped with the larger dimension on the top). The reason is that during use a lot of pressure is place along the top of the tool (wood surface you are working) causing the head to pull from the handle - therefore the need for a tapered socket. Good luck, and keep up the nice work. -Charlie
  16. Very nice - nicely sized scrolls. I like the upset feet on the first one. Might you try making your collars with a bit of shape to match the feet (they'll look like they belong) - a length wise fullering along a bar about the same width of the scrolls (or maybe 12mm) so that the center is thinner than the edges (use a large enough fuller so that the edges of the bar will be the thickest part - as if upset like the ends of the feet), then cut to length and form for collars. Boy, I hope I explained that clearly. -Charlie
  17. VaughT, jhinks2013; - I'm of he opinion that it would be ill advised to motorize this linkage without some significant beefing up of the linkage (thicker arms and trussed center pivot point (B). Since this linkage only uses, at best 180 deg of rotation at Ao, larger beefier arms will add additional inertia to overcome with each change in direction and this will reduce your efficiency (something in the linkage has to give). Additionally, your motorization linkage would need to be able to absorb and accommodate the shock of impact and any change in impact travel as a function of material thickness (That is part of the function of spring or strap linkages on most power hammers). Think about this for a moment. Lets consider a small version of this treadle hammer, something where the pivot arm "a" has a length of 4 inches - this means that the long arms will be 20 inches long and the ram will travel approximately 17 inches vertically (more than enough room to accommodate most any tooling (dies, punches, chisels, etc), your work piece and have room for accelerating the ram. Now would you want to stand in front of a 25 or 50 lb ram suspended on some relatively minor mass arms cycling at a rate of 200 or 300 times per minute - as you would likely want with a power hammer? Treadle hammers and power hammers serve slightly different needs - they each have their place, even if there can be overlap in use. Steam train linkages are just a bit different, but you must keep in mind that with train linkages the travel was a constant distance and there was little need to accommodate impacting forces. Now I'm not going to say you can't motorize this type of linkage, but I wouldn't. For all the trouble that you'd go through, the ram would never travel as securely at higher cycling rates as you'd want, and need, it to do (partially due to the nature of all the linkage). Additionally your wheel to drive this linkage would need to be of significant enough diameter as to negate one of the key features of this mechanism - that of compactness. If you want a power hammer for drawing, etc, just build a power hammer (there are numerous plans on this site for tire hammers that are very good) - you'll be far happier, likely safer, and have more time for forging. Most, possibly all (I need to think about this one), treadle hammers that I've seen that were motorized were poor substitutes for the power hammers that their builder's wanted them to be. -Charlie
  18. Sorry, but in the interest in trying to direct someone from making a misguided mistake, I am going to rain on the parade. Budgets are tight and all, but doing anything short of having a solid steel (or CI) anvil base for your power hammer, that you've likely just spent days or weeks building, is the same as spending $200USD on the finest hand hammer only to use it on a 25lb ASO of low grade Cast (?). No matter what you fill that tank with, or how tightly you pack it (even if you fill the voids with hot lead), you will never get the rebound needed to efficiently counter the blows of the ram (I guess, unless your ram only weighs 1lb - and I doubt that). Your power hammer will still work (even if the cylinder is left empty), but you likely will not be anywhere near as satisfied with its performance as if you where to acquired a proper anvil for it. I've looked at so many well designed and crafted power hammer mechanisms that were mated up to dead anvils - just sad to see all that energy and effort go to naught. You have to do what you have to do, but you can't pack concrete, sand, rust, old car part, or anthing else anyone else can think of, tight enough to come close to even the poorest grade CI (the resultant the material densities and Youngs Modulus are not even on the same page as solid steel). Weight is important, yes, but it is far more involved than just weight. Weight will help keep the entire assembly from dancing across your floor, but for the ram's blows to be effective at moving metal, the blows of the ram need to be countered (reflected may be a better word to describe what the anvil needs to do) by a suitably sized mass of equal or better strength (and since I going out on a limb here and speculating that your ram face is some type of mild or possibly tool steel, it would mean that you should use a suitably sized mass of solid steel to reflect the blows of the ram). When I state "suitably sized" I mean at a bare minimum a 10:1 mass ratio (anvil to ram). I believe there is even a chart to this effect listed in one of this forum's pages on power hammer construction, if not I'm sure that ABANA would have this information for you to verify what I've just written about. Good luck on your choice.
  19. Matthewj, Creative and absolutely beautiful work. I'm fairly new to this forum, so I don't think it's up to me to make a formal welcome (I'll leave that to the members with more time - I was suprised that 20+ views by others before me yet no one had made a response) but as a Mainer it's nice to see your caliber of work in the state. Based on the examples shown of your work I'm sure you'll be able to teach us all something. -Charlie
  20. Jason, I saw this post about 3 weeks ago and just had to go digging around in my files for some of my old drawings as I had worked on this design some years ago but never did anything beyond a bunch of sketches and calculations (too many distractions). For your benefit, and that of others interested in straight-line linkages, I shall share here some of my findings and suggestions regarding adoption of a Hoecken's mechanism to the a treadle hammer. By no means do I consider myself the final word on this mechanism, nor should anyone else, as there are many more experienced smiths here, and probably more than a few engineers, on this forums that could share a great deal more knowledge regarding these mechanisms and treadle hammers in general. If you're interested in greater detail or further explanation of my my calculations I shall gladly present them (I've got about 20 pages of notes and calculations on this design and about again that many pages of free-body diagrams showing forces at all the pivots under various conditions). I've learned a lot from others on this, and other, sites and believe in sharing information if it helps further the craft and saves someone from having to reinvent the wheel. Now, first off I need to state that this design might not produce the same or a greater amount of impact force as some other treadle hammer designs, say the late Grant Sarver's hammer with “whip,” but all designs are a trade off of sorts. Where Grant's might have had a the advantage of energy stored in the spring added to the force of gravity, its space requirements in the smithy were significant, whereas this design will yield a very compact foot print and still offer a very potent impact force. In my opinion if you're looking for a treadle hammer for drawing out quantities of metal, get a power hammer. IMO treadle hammers are great for limited forging elements, shaping, punching etc when you need a bit more oomph than a hand hammer can provide or a third hand, but for long draws or production work, a power hammer is hard to beat. For the general audience: The Hoecken's mechanism is unique in the category of the straight-line linkages due to the fact that it deviates off true straight line by less than 1% over the portion that is “straight-line” (approximately 60% of the travel of the wheel or rotation of link “A” in the drawings). Additionally the linear velocity of travel of point “C” (see drawings) is relatively constant over this duration of travel. No other straight-line linkage mechanism, that I know of, can boast to this claim – if someone knows of one please enlighten me, as in my research I have not found another. Now to maintain these characteristics of travel it is very important to adhere to the linkage ratios. As you increase or decrease the ratios of the arm lengths relative to “a” you cause “C” to travel in an increasingly divergent and oscillating motion having a backwards “s” curve or forward “s” curve, respectively. Depending on the mass of your ram, overall weight of the entire assembly and construction quality this could prove harmful to your linkage or downright dangerous to the operator. Now, Jason, as for your posted “design” (using your start and stop limits considering the 3 o-clock position as zero degrees and the 9 o-clock position as 180 degrees and your use of a wheel for your drive geometry, the ram will experience, not accounting for initial start acceleration of your foot placing the mechanism in motion, an 11% acceleration over the first 30 degrees of rotation and then the ram velocity will be constant (of course considering that your foot is descending on the treadle at a constant speed – which it likely will not be) over the next 120 degrees and will decelerate 9% over the last 30 degrees of your 180 degree wheel arc. I will suggest an improvement to this in a bit. I believe you mentioned that you were thinking of using roller chain and sprockets to the drive the mechanism. May I offer a cause of pause regarding this plan. The additional mass of a roller link chain will cause you to have to work harder to over come its inertia without any appreciable benefit – you may find a cable and sheave (pulley wheel) a better option (far less expensive and lower mass). Now before someone starts mouthing off about cable stretch relative to the roller link deformation under load – park it! Under the forces that any “normal human can directly exert on a short length of 3/16 inch diameter, or better, 7x19 cable will never amount to anything worthy of mention. Next, may I suggest that you reduce the face area of your ram (6x6 to something on the order of 3x3 or 3in round) to concentrate the ram energy. Next, to improve the overall efficiency of each strike in deforming metal, increase the mass ratio of anvil to ram (absolute minimum should be 10:1, though many would state that a minimum of 15:1 or 20:1 as a more desirable ratio – again simple physics will demonstrate the rationale for this). I mention this only because of your use of equal size masses on both ram and anvil in your earlier design (the linkage of which I would consider absolutely ingenious – It appears to be a mashup of a parallelogram and a contorted Peauclleier mechanism – why people keep comparing it to a Watts mechanism is not understood by me – but I'm a little on the slow side). The physics of deforming (smashing) metal between ram or hammer and anvil is neither a purely elastic nor inelastic interaction, but somewhere in between, and if you want to have the greatest effect on the work piece at the anvil, under the power of ram or hammer, you want, among other things, the mass and strength of your anvil to be such that it is able to easily counter and reflect any force that you impart on the metal to be deformed. Otherwise considering the modulus of the steel you are trying to deform (yes, temperature does have a function in the deformation, as does interface friction, etc) you will just be trying to put the anvil into motion instead of squishing your work piece. If someone needs empirical evidence to this concept, just find yourself a 1 foot length of the largest size railroad rail you can find (120 or140 lbs/yard) (I choose railroad steel as it is very strong steel – makes great dies - and readily available) anchor it to a stump of comfortable height, and heat up a 1” square piece of A36 steel to 1400 deg F, take your 3 lb hammer and strike the steel over the rail bead as hard as you can (one blow), quench it, and now take the other end of that same piece of A36, again at 1400 deg F and strike it the same on a 300 lb anvil mounted on a similar stump. If that doesn't convince anyone to the importance of a large mass ratio between anvil and hammer don't bother reading any further in my post as you'd be wasting your time. Now to improving on the posted design. May I suggest the use of a spiral instead of a wheel of constant radius to rotate moment arm “a” through its path. The rationale for this is such: Given the unique nature of this mechanism having near constant velocity at “C” relative to rotation of “A” (for the arc segment that you have selected to use - IMO approximately the best segment of the arc for this purpose), use of a circular path to drive “A” will result in kinetic energy in the ram dictated by the speed of your foot and approximated by the equation KE=(m*v^2)/2 (I'm not going to get into discussing impact forces, thermal energy losses, internal elastic energy losses or any other losses here – they are not important to the discussion at hand). (gravity will not enter into the impact force as the force of gravity on the ram is more than countered by the mechanism's return spring (more on this later). So, though it has been several decades since I took any college math or physics course (no I am not a teacher of either, nor am I an engineer), it is easy to see that the element of the equation that you want to maximize is the impact velocity (since velocity gets squared) - any incremental increase over the constant velocity achievable by a circle will result in a greater impact force, and we know this translates to more metal squishing. So in my drawings I have shown a spiral (equation shown in polar coordinates) that will result in pivot “A” traveling at near twice the velocity at the end of the 180 degree arc as compared to the beginning. There are many different spiral to choose from but the equiangular is in my opinion the best for this application. To add further to the acceleration, and therefore the terminal velocity of the ram, you could also add a toggle linkage to the treadle linkage to cause acceleration. I will not go into treadle linkages here as optimum selection would generally be dependent on the strength of the smith and size of the treadle hammer assembly. I would also suggest the use of alloy steel socket shoulder screws with bushings or bearings for pivots (don't even consider common grade 5 or 8 hardware as dimensional tolerances are suboptimal and the wear at the pivots and slop in ram travel will show in very short order – you could get away with that stuff in the treadle linkage but not in the ram linkage or mechanism). Remember that due to the number of pivot joints each thousandths of slop at a pivot is magnified at the ram proportionally by the length of the linkage arm. Now I'm going to simplify a lot in this next example, so for anyone who's a stickler for nth degree accuracy and inclusion of all the variables that could be included, forget it – there's not enough space nor time here to account for all the variables, nor is it warranted. Lets just show the difference in the terminal KE between using a circular drive versus the spiral that I suggest in the drawings. First I have to figure out how fast I can drive the ram down from the uppermost position to the lowest position (anvil face). Well I can't do that without having the treadle hammer build – and as I stated above I haven't done that (except for a wooded ½ scale prototype). But, though I feel fairly comfortable that I can stomp down 10 inches with my foot a good deal faster and harder than with my fist, I'll just use the downward speed (velocity) that I can swing my 2-1/2lb hammer over a 22+ inch arc. This ended up being a velocity of 3.65m/s (though not perfectly accurate, this was number was calculated from the number of hits on a flat piece of steel on my anvil over a 1 minute period – now at 45 seconds I could definitely feel a slowing in my pace but we'll go with the final 1 minute average anyway). So using that speed as a datum for our treadle speed I'll calculate the difference between between a 25lb ram using the constant velocity of the standard Hoecken's mechanism with a circular drive vs a spiral drive path to give a measure of comparison. If we take the KE equation I mentioned above to calculate the energy at the ram face just before it strikes the anvil after traveling from the top most point or zero degrees of rotation of the linkage (in this example lets just use the 180 deg rotation as the impact point). The height doesn't matter as the force potential from gravity is more than canceled by the force of the return spring. I could add potential energy (PE) but in this scenario it would not be a significant contributing force. So lets just go with KE, yes a simplification, but highly demonstrative. Now I have to remove the force of gravity from the ram's weight to find its mass for use in the equation. (I use metric units in all my calculations as the calculations and conversions are simpler – I don't like working with slugs, but I'll give the resultant to the equation in both metric and US common system of units.) First I convert the 25lb force to Slugs to kg mass, this yields: 11.36kg. Now using the velocity that I stated above for my ram velocity (though it would probably be faster if I were to use my foot on a treadle over a 10inch stroke), 3.65m/s, plug all this into the equation KE = (m * v^2)/2, yields 75.69 kg-m^2/s^2 (N-m) or 55.82 lbs-ft force. Nice mechanical gain but not really impressive. Now if I consider the use of the spiral where the terminal velocity will be twice (7.3m/s) that of that of the circular drive wheel then the resultants are: 302.7 N-m or 223.3 lbs-ft. That is a significant difference – one that will move some hot metal. I've gotten a bit too wordy already but I still need to share my thoughts on the return spring force. Though none of the springs that will be used on a treadle hammer will be Hookian (comply with Hooke's law, F=-kd) the spring constant concept still applies to this application. As the return spring stretches (ram moving downward toward the anvil) the force generated by the spring increases and is not just opposing the force of gravity but also the force you are generating by your foot on the treadle. To attempt at reducing this opposing force I would suggest the use of a spiral at the Hoecken's mechanism pivot for return. This spiral would need to be configured with the larger radius tangent to the return cable with the ram in the “parked” position and the small radius tangent to the return cable with the ram at the anvil (see drawings). It is a matter of moment arm length. Such as the force of the spring increases with displacement you want it acting on a shorter moment arm to reduce the torque generated. How short or what rate of spiral will be dependent on the “k” factor of the selected spring. I've tested the seven garage door type springs I've collected for these types of projects and they each have slightly different “k” factors (none of them is Hookian so you have to evaluate the spring over the range of travel you plan based on the size of linkage you are considering, to figure the torque needed to slightly better than balance gravity with the ram is “parked” and then figure the rate of spiral for when the ram is deployed). Well this is far longer winded than I had planned but this is the just the basics. I reduced the size of my images to below 300KB, after reading some posters stating that this was necessary for the inclusion of images. I wish I could've embeded the images in the text but, I'm new to all this forum stuff and maybe in time I'll figure it all out. I've included a few pics of the 1/2 scale wood prototype that was built to better show some of the geometry. If these aren't clear on the forum i imagine that I could email them directly if someone wants. I hope that these ramblings help you or others in some way in your consideration of this mechanism for use in a treadle hammer or provided things to think about for other designs – just remember they are all trade-offs, each having unique strengths and one or more weak points – only end application can determine what is “best.” -Charlie
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