Jump to content
APC Forum

Shell wrapper


rcfun42

Recommended Posts

Well a few weeks ago I seen a shell wrapper on u tube and started making one and have got it mostly done except the one bearing for the c clamp under the machine I cant quite figure out how it works and if anyone can help I would be grateful for the help. I have been wrapping them by hand for the last 4 years and getting so many to wrap it is hard to keep up with it but anyway if you want to see it it is home made shell wrapper and it is by fireworks 17 so if someone can help me that would be great. I will check back on Thursday for answers if any and thanks. rcfun42

Link to comment
Share on other sites

I built the machine. The bearing assembly uses a standard ball bearing. McMaster Carr has them. The one I used was 1.25" od x 0.5" Id 0.375" thick. Sandwich the bearing between a short 1/2-20 bolt and tighten a nut down.

You have to machine out a piece of metal to 1.125" diameter and deep enough to press the bearing into the piece and have the cut deep enough to accept the total thickness of the bearing and the bolt head. I machined the bolt head down to make it thinner. Then u need to drill and tap the closed end of it for 1/2-20 threads so you can use the coupling nut that is welded to the upright.

post-20656-0-33900000-1481683688_thumb.jpg

post-20656-0-31791400-1481683774_thumb.jpg

  • Like 1
Link to comment
Share on other sites

i use a thrust bearing on mine, as the load is mostly thrust not radial. If you drill out the threads in the holesaw and use a threaded rod that fits the hole, you can save on machining. Simply place the thrust bearing between the holesaw and a nut on the threaded rod. The nut is used to clamp and unclamp the shell.

Edited by Col
Link to comment
Share on other sites

I had thought about using a thrust bearing for this application but figured if I did it the way you did yours then you were limited to the clamping range of the internal depth of the hole saw. I also thought that with the hole saw just kind of sitting on the rod there would be some slop in that connection. Ball bearings can take some trust forces and still operate and with this force being so small I didn't see an issue with it. Regardless it is another way to achieve the same results.

 

Col

Do you have any pictures of your machine?

Link to comment
Share on other sites

I went with the non machining option cos forstener bits dont do so well in metal ;) I didnt use a hole saw for the lower clamp, just a piece of steel tube with teeth filed into it. As long as the tube id is close to the threaded rod od there`s no slop. I have different top and bottom tubes for each shell size. The top tube lengths are geared to put each shell size in the right place without any adjustments so its just a case of moving the bottom tube upto the shell using the nut behind the thrust bearing.

I think there`s some pics and a vid somewhere.. and after a quick look around:

http://www.amateurpyro.com/forums/topic/10890-low-budget-shell-wrapping-device/?hl=+wooden%20+pasting%20+machine

Edited by Col
  • Like 1
Link to comment
Share on other sites

i use a thrust bearing on mine, as the load is mostly thrust not radial. If you drill out the threads in the holesaw and use a threaded rod that fits the hole, you can save on machining. Simply place the thrust bearing between the holesaw and a nut on the threaded rod. The nut is used to clamp and unclamp the shell.

 

Do you have plans or a tutorial for building your pasting machine? I've watched a couple of videos and it's an nifty idea that I may try my hand at, but I'm far better at following written instructions than I am designing something solely based on what my peepers are seeing.

Link to comment
Share on other sites

Hi Mondo

I didnt do any plans, it was more a series of ideas (back of the fag packet stuff) for the different bits that were shoehorned to work with what i had on hand. A motorised version would be a doddle to make but it doesnt have the same appeal as hand cranked wooden gears :)

Link to comment
Share on other sites

Well after a lot of thought it suddenly hit me on the way the bearing works so now i'm about 90% done with the wrapper and hope it works as well as the one i'm designing after. It is working good so far so now all I have to do is get the angle right and i'm in business. Thanks for all the help on this project.

Link to comment
Share on other sites

Just make sure you get the shell centered up in the middle of the lazy Susan bearing. You want the shell to stick up through the bearing to where the gummed tape is put on just higher than the horizontal centerline of the shell
Link to comment
Share on other sites

That's what it looks like but I've never found any that pulled from the roll that easily without shredding.

Link to comment
Share on other sites

It looks like the shell angling mechanism may be a pain to construct. I noticed they changed the angle several times during wrapping. We can't see the workings but it looks like a hinge with the screw just above it angling the rod the shell is mounted on. The rest could be built from a cheap drill press.

Link to comment
Share on other sites

Another similar design but horizontal rotation, cellotape (non biodegradable) and masking tape (weaker and more expensive than gummed) with this one. Compact and nicely built though.

Link to comment
Share on other sites

OM I don't think that is an angling mechanism. It looks to me as if it is a slide mechanism and it is moved away from the taping arms if the tape starts creeping up onto the spollete tube. I like this machine, I use masking tape for most of my round shells. The tape I use is simple masking tape cut from the log in a chop saw. It's a lot cheaper then one may think,ive pasted 120-3" shells with a 20$ log from the paint department in HD. As long as the saw makes a strait cut the tape unwinds by hand without tearing. The chop saw needs brushed off with a wire brush between cuts otherwise the blade gets gooey and sticky.
Link to comment
Share on other sites

Link to comment
Share on other sites

×
×
  • Create New...