allrocketspsl Posted February 15, 2012 Share Posted February 15, 2012 Here`s another piece of the puzzle http://i770.photobucket.com/albums/xx341/colinspyro/shell%20pasting/basiclayout.jpg Another piece of the puzzle almost finished you know Col after careful thought i could make that is the center post holding the shell rotating at a certain rate to the outside whell,are they connected some how?I mean i could hand rotae i bet and get good results? All Link to comment Share on other sites More sharing options...
Col Posted February 15, 2012 Share Posted February 15, 2012 (edited) With the wheeled version, the shell speed changes along with the angle. With the smaller machine, that one uses a fixed angle and shell speed although each shell size would need a different speed. The small machine rotates at 120rpm, the large wheeled machine 100rpm. I`ve been wrestling with VB.net code all afternoon to sort out some automated control, last time i coded anything was on a ZX Spectrum Edited February 15, 2012 by Col Link to comment Share on other sites More sharing options...
Zmuro Posted February 15, 2012 Share Posted February 15, 2012 I draw this machine in SolidWorks, without motors but just to get the feeling of size. I wouldn't worry about speed control that much, I'm more trial and error guy. You could synchronise shell rotation with second motor which has a speed control. http://shrani.si/t/r/HR/1jTk3AdR/pasting-machine-3.jpg http://shrani.si/t/3A/Od/ZWeDwEZ/pasting-machine-1.jpg http://shrani.si/t/1V/Cb/3Asy5NSz/pasting-machine.jpg http://shrani.si/t/b/5b/4xjJVVSo/pasting-machine-2.jpg Link to comment Share on other sites More sharing options...
dagabu Posted February 15, 2012 Share Posted February 15, 2012 I draw this machine in SolidWorks, without motors but just to get the feeling of size. I wouldn't worry about speed control that much, I'm more trial and error guy. You could synchronise shell rotation with second motor which has a speed control. http://shrani.si/t/r/HR/1jTk3AdR/pasting-machine-3.jpg http://shrani.si/t/3A/Od/ZWeDwEZ/pasting-machine-1.jpg http://shrani.si/t/1V/Cb/3Asy5NSz/pasting-machine.jpg http://shrani.si/t/b/5b/4xjJVVSo/pasting-machine-2.jpg Looks like the pictures didn't post, Z. -dag Link to comment Share on other sites More sharing options...
Zmuro Posted February 15, 2012 Share Posted February 15, 2012 (edited) Looks like the pictures didn't post, Z. -dagI see the pictures just fine. Anyone else having problem seeing pictures? Edited February 15, 2012 by Zmuro Link to comment Share on other sites More sharing options...
Zmuro Posted February 15, 2012 Share Posted February 15, 2012 I uploaded pictures to forum in case anyone else is having problems. Link to comment Share on other sites More sharing options...
dagabu Posted February 15, 2012 Share Posted February 15, 2012 That's pretty sweet Z. It looks pretty easy to haul too if the frame can be kept that flat. -dag Link to comment Share on other sites More sharing options...
Col Posted February 15, 2012 Share Posted February 15, 2012 Nice graphics. If you are going to use multiple angles you`ll need fairly tight control over the speed and angle change. Controlling everything via a pc is the best option. Link to comment Share on other sites More sharing options...
FrankRizzo Posted February 16, 2012 Share Posted February 16, 2012 Looks good, Zmuro! I can see the pictures in your original post, and in Dag's reply. Must've been a server glitch. Link to comment Share on other sites More sharing options...
allrocketspsl Posted February 16, 2012 Share Posted February 16, 2012 thatnks i gotta make one of those for sure Link to comment Share on other sites More sharing options...
NightHawkInLight Posted February 16, 2012 Share Posted February 16, 2012 (edited) That looks pretty good. Quite a bit of experimentation will be needed to get it working right I'm sure, but looks nice. A fellow pyro that's about 45 minutes away from me has made himself an extremely simple and very fast pasting machine. Does about 1,000 on it a year. I'll have to take some video next time I'm there to show you all. More or less he's got the shell on powered wheels with an electronic timer with various presets for each size shell. There's a bar above the shell that's under spring tension which applies a constant strip of gummed tape fed through wet sponges. You hit a foot pedal and the timer fires up the motors to spin the shell exactly one full rotation then shut off. You then rotate the shell by hand about the width of the tape and hit the pedal again. You can get fast enough at it that the shell hardly stops moving. Pastes a 6" shell in something like 4 minutes. Once the desired amount of layers has been reached you rip the tape, just throw a switch to bypass the timer and the motors constantly spin the shell until it's smoothed out to your liking. They end up looking extremely clean. Very simple and effective design that can be (and was) made out of scrap. Edited February 16, 2012 by NightHawkInLight Link to comment Share on other sites More sharing options...
Zmuro Posted February 16, 2012 Share Posted February 16, 2012 Nice graphics. If you are going to use multiple angles you`ll need fairly tight control over the speed and angle change. Controlling everything via a pc is the best option.On the pictures above there is 8" shell, so I guess the machine could be made a little smaller if the maximum size of the shell would be 8".Could you tell us a little more about controlling motors via PC? What kind of motors will you be using? Link to comment Share on other sites More sharing options...
Col Posted February 16, 2012 Share Posted February 16, 2012 (edited) I`m using a 3/4hp to turn the wheel and a pair of high torque (35lb-ft constant / 219 lb-ft stall) geared motors for shell rotation and angle change. Controlling motors via usb is fairly easy as there are plenty of boards available, the hard part is learning enough visual basic to get it to do what you want The board i have can control 2 dc motors independantly forward,reverse with pwm speed control.There are 6 digital outputs (need one for controlling the mains motor) and 8 digital inputs (useful for monitoring shaft rpm` s etc), some can be configured in software to act as limit switches which is quite useful for the angle change motor. Edited February 16, 2012 by Col Link to comment Share on other sites More sharing options...
Zmuro Posted February 16, 2012 Share Posted February 16, 2012 Where did you buy that controlling board and DC motors? I googled a little but they are quite expensive. Link to comment Share on other sites More sharing options...
skysparkler Posted February 16, 2012 Share Posted February 16, 2012 (edited) Hi I have a foto of my first job on a pasting tool and som iliustration similar to china factory small shell pasting machine http://v7.lt/images/1328944101.jpghttp://v7.lt/images/1328437830.jpghttp://v7.lt/images/1329362931.jpghttp://v7.lt/images/1328815382.jpghttp://v7.lt/images/1328576554.jpghttp://v7.lt/images/1326902065.jpgmaybe it will be helpful Edited February 16, 2012 by skysparkler Link to comment Share on other sites More sharing options...
Col Posted February 16, 2012 Share Posted February 16, 2012 (edited) @ZmuroI bought the board from an online store, including a 16A mains relay and transistor (for switching the 3/4hp motor), project box and usb cable it came to around $80 at the current exchange rate. I bought the motors locally to save on postage, they were around $94 the pair but should last a lifetime.I guess the total cost will come in under $300, which isnt too bad when you consider a wasp is probably around $2600 to import and thats without 50lbs of international shipping Here`s an example of the control program if you fancy downloading it for a look. Its only the first draft so its very basic but it`ll give you an idea of the sequence of events. Control ProgramWhen the program pauses at the end that initiates a time delay (eg 5-10 seconds) so you can cut the tape. When the delay expires it restarts the wheel and shell motors for the burnishing run and switches everything off when its done. The Burnish line isn`t coded as yet but it just shows the burnish run progress and also reports when the angle change motor has returned to its starting position ready for the next shell. @SkysparklerThats nice a bit of DIY Edited February 16, 2012 by Col Link to comment Share on other sites More sharing options...
Zmuro Posted February 16, 2012 Share Posted February 16, 2012 Did you already implement those functions, beside burnish? Do you have any formula to calculate shell rotation at different angles if the wheel is rotating let say at 60 rpm?Can you share a link to that online store? Link to comment Share on other sites More sharing options...
Col Posted February 16, 2012 Share Posted February 16, 2012 (edited) The store is uk based but they may ship worldwide, My linkThe program will control the motors as it is but i`d like to incorporate more features, especially the digital inputs for realtime motor feedback.as the rpm will change under load. The math is fairly straightforward for a fixed angle, use the wheel speed, shell circumference and tape width to calculate the shell speed. Tape thickness and the number of overlaps will govern how much the shell grows in size per pass which affects the speed so there are a few variables involved. A fixed shell angle is easier to figure out but the pasting will be at least 4x thicker at the poles compared to the equator. Edited February 16, 2012 by Col Link to comment Share on other sites More sharing options...
Zmuro Posted February 17, 2012 Share Posted February 17, 2012 I took my SolidWorks model to next stage and added motors. I calculated shell rotation speed which depends on the angle of swing arm. On the video you can see pasting of 8" shell with 20mm wide tape at three different angles. Wheel rotates constantly at 60rmp.http://www.youtube.com/watch?v=70-q5jLP6lY Link to comment Share on other sites More sharing options...
NightHawkInLight Posted February 17, 2012 Share Posted February 17, 2012 Very cool, that looks like it might just work. When you get to the third position though, will you not be trying to paste over a deep crater formed by so much tape around the equator of the shell with none towards the poles? Perhaps it won't be an issue, it just seems like it would be difficult to get the tape to lay smoothly. Link to comment Share on other sites More sharing options...
Zmuro Posted February 17, 2012 Share Posted February 17, 2012 (edited) I know what you mean. Maybe it wouldn't be necessary to paste whole shell at each angle. I will have to look at chinese pasting machine video a few more times Edited: I looked the video again and the shell is fully pasted at each angle. Maybe I should use wider tape or narrower angles? The swing arm rotates 25 degrees each time. Edited February 17, 2012 by Zmuro Link to comment Share on other sites More sharing options...
Col Posted February 17, 2012 Share Posted February 17, 2012 (edited) NHL, i dont think it`s much of an issue as the transition points only form a slight step, its the the poles that have more of a crater http://www.youtube.com/watch?v=tX5bDcDzPKo Zmuro, Thats a nice animation. Its not easy to get a constant wheel speed as the glue and tape will alter the weight distribution as they are used up. My wheel weighs about 2kg fully loaded, the tape and glue will account for about 20%. The best plan is to use a fairly beefy motor, drive both shafts and spring load the top guide wheel to keep the wheel in firm contact with the drive wheels. That will give you maximum traction and minimise any slippage. This vid was taken after the drive wheels were locked onto the shafts with the collets. The wheel ran a lot smoother compared to the friction fit only drive wheels in the earlier vid. http://www.youtube.com/watch?v=OQjDBsx2vAY Edited February 17, 2012 by Col Link to comment Share on other sites More sharing options...
NightHawkInLight Posted February 17, 2012 Share Posted February 17, 2012 Now that I look back at the previous page on this thread I notice there is a video of the device, and my concern about the crater is negated because they don't actually even try to cover it. Here's the long form video with a compilation of machines including the one that is being discussed here, as well as a similar design at the end that pastes in what looks to be the same type of pattern but with no wheel at all: http://www.youtube.com/watch?v=sKr09cHIYC8 Link to comment Share on other sites More sharing options...
Col Posted February 17, 2012 Share Posted February 17, 2012 (edited) Skysparkler`s new design is the same as the non wheeled machine in the vid. The build up at the poles isnt an issue with a 2" shell as they dont need a lot of pasting. Larger shells would be more problematic using a fixed angle as they`d need a lot more layers. There is a way to use the fixed angle with larger shells which involves moving the poles after each layer (same as 3 axis, 7 axis hand pasting) so the buildups are distributed all over the shell. You`d have to use a magnet to locate the fuse like the Wasp. The main issues are keeping track of where the poles are..under the pasting and readjust the shell rotation supports after each layer to recenter the shell. Edited February 17, 2012 by Col Link to comment Share on other sites More sharing options...
californiapyro Posted February 17, 2012 Share Posted February 17, 2012 http://www.alibaba.com/product-gs/466260744/Shell_Pasting_Machine.html that machine in the video is available for $3500 dollars... would you rather have a WASP? Link to comment Share on other sites More sharing options...
Recommended Posts