The rocket itself is the dart, as it were. Of course, it wasn't originally intended to be a passenger craft, but here we are...
I do see exactly what you’re saying about the nose.
I do see exactly what you’re saying about the nose.
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Plasma Dart II Build Thread
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Payload Section
And now for some boring stuff, in contrast to exciting centering rings.
The payload section consists of a balsa 5055 transition, some BT50, and a balsa ogive nose cone. I started by CAing the nose in my current preferred fashion: one or two coats of CA, followed by sanding, followed by a coat of thinned CWF, followed by sanding. Done. While staring at the balsa transition, I thought: "Why not CA that thing as well?" Well, it turns out that there is a very good reason not to, beyond the simple matter of it not being necessary: it's very hard to sand. I decided I didn't need to go too crazy sanding the CA, since I would be filling in the remaining irregularities with CWF.
I glued the transition to the payload section body tube, then liberally smeared thin CWF over the BT and the transition. After sanding, it looks like this:
You can see that the transition is showing a lot more CWF than usual after CA, due to the fact that I didn't go crazy sanding the CA. Unfortunately I think the surface is a bit irregular; I might apply one more coat of CWF in an attempt to level it out. The joint between the transition and body tube i smooth as silk, however.
Oh yeah, I punched three altimeter holes. The picture shows one of them.
Next up: the nose cone twist lock. This will be the third rocket I've used one of these on, and the second BT50. Glad I had multiple copies printed back when I made them, still have some more left. For those who didn't see those previous builds: this is a 3D-printed lock mechanism so I can easily secure and remove the nose cone for access to the payload compartment. Here's a render of the BT60 version:
Here's what I started with:
I neglected to go back and see exactly how I installed these in the past, but figured I remembered well enough. First, I placed the two pieces, locked together, lightly into the end of a piece of scrap tubing, and slathered some epoxy onto the surface of the piece that would attach to the nose cone:
Using a piece of coupler, I pushed it slightly into the tubing, taking care not to disturb the epoxy:
Then I pressed the nose cone in, just enough to make good contact, and left it to cure.
The key to this whole process it so make sure that the epoxy stays where it's supposed to, so you don't end up gluing the whole assembly together. Happily, it came apart cleanly the next day.
Next, with the pieces latched together (as shown above)I applied some epoxy to the inside of the payload tube in the correct location, and inserted the whole assembly, and again let cure. This time, the hope is that the nose and attached piece will come out, and the anchor will stay in the body tube. Once again, success.
Back in the Biohazard days I made a little video to show it in action. It's very satisfying to play with.
The payload section is now complete save for the canards. We'll get to those soon.
And now for some boring stuff, in contrast to exciting centering rings.
The payload section consists of a balsa 5055 transition, some BT50, and a balsa ogive nose cone. I started by CAing the nose in my current preferred fashion: one or two coats of CA, followed by sanding, followed by a coat of thinned CWF, followed by sanding. Done. While staring at the balsa transition, I thought: "Why not CA that thing as well?" Well, it turns out that there is a very good reason not to, beyond the simple matter of it not being necessary: it's very hard to sand. I decided I didn't need to go too crazy sanding the CA, since I would be filling in the remaining irregularities with CWF.
I glued the transition to the payload section body tube, then liberally smeared thin CWF over the BT and the transition. After sanding, it looks like this:
You can see that the transition is showing a lot more CWF than usual after CA, due to the fact that I didn't go crazy sanding the CA. Unfortunately I think the surface is a bit irregular; I might apply one more coat of CWF in an attempt to level it out. The joint between the transition and body tube i smooth as silk, however.
Oh yeah, I punched three altimeter holes. The picture shows one of them.
Next up: the nose cone twist lock. This will be the third rocket I've used one of these on, and the second BT50. Glad I had multiple copies printed back when I made them, still have some more left. For those who didn't see those previous builds: this is a 3D-printed lock mechanism so I can easily secure and remove the nose cone for access to the payload compartment. Here's a render of the BT60 version:
Here's what I started with:
I neglected to go back and see exactly how I installed these in the past, but figured I remembered well enough. First, I placed the two pieces, locked together, lightly into the end of a piece of scrap tubing, and slathered some epoxy onto the surface of the piece that would attach to the nose cone:
Using a piece of coupler, I pushed it slightly into the tubing, taking care not to disturb the epoxy:
Then I pressed the nose cone in, just enough to make good contact, and left it to cure.
The key to this whole process it so make sure that the epoxy stays where it's supposed to, so you don't end up gluing the whole assembly together. Happily, it came apart cleanly the next day.
Next, with the pieces latched together (as shown above)I applied some epoxy to the inside of the payload tube in the correct location, and inserted the whole assembly, and again let cure. This time, the hope is that the nose and attached piece will come out, and the anchor will stay in the body tube. Once again, success.
Back in the Biohazard days I made a little video to show it in action. It's very satisfying to play with.
The payload section is now complete save for the canards. We'll get to those soon.
Nicely done. Nifty design and asembly process. But...
When, especially in low power stuff, would you need this sort of lock rather than a tight friction fit?
When, especially in low power stuff, would you need this sort of lock rather than a tight friction fit?
Friction fit would work... but especially with a flimsy BT50, I don't like having to worry about how tight it is. With the lock, I can make the nose cone nice and loose, and still not have to worry about losing it, period.
Just a fun thing, not required but nice.
Just a fun thing, not required but nice.
Canards
Here are the little canards:
Yes, of course I papered them.
I glued them to the payload section and here it is, finished:
If you click fo the larger image, you can see the vent holes just above the aft part of the fins. That spot should be under a decal, so it will be a bit less visible than if it were in the white area.
Here are the little canards:
Yes, of course I papered them.
I glued them to the payload section and here it is, finished:
If you click fo the larger image, you can see the vent holes just above the aft part of the fins. That spot should be under a decal, so it will be a bit less visible than if it were in the white area.
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Wow, what a relief! I was thinkin’, “is he crazy? Those two tiny holes would spoil the whole look of the rocket if they were on a white background!”
I spent a few minutes trying to think of a cute way to integrate the holes into the decor, but I couldn't think of anything good. If I had the whole rocket festooned with little hatches and ports and warnings I could do something there, but I don't want that to be the only place for such a thing on the rocket.
GlenP
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Polka dots? A red max helmet with a bullet hole? Lots of ways to camouflage a vent hole. Or just put a label next to it that says: VENT.
I suspect BABAR was being facetious that those little vent holes have a snowballs chance in a rocket plume of detracting in any way from the overall rocket, which I am sure you realize. I applaud your attention to the details.
I suspect BABAR was being facetious that those little vent holes have a snowballs chance in a rocket plume of detracting in any way from the overall rocket, which I am sure you realize. I applaud your attention to the details.
A "vent" label would probably be exactly what I'd put there if there were other similar sorts of things elsewhere on the rocket. My Accur8-skinned rockets have endless small details like that but in general I don't really know how to do all that stuff in an intelligent way. If John Pursley designed this rocket it would look very different I suspect.
Yeah I picked that up.
Mounting the Rings
What is more fun than talking about centering rings, I ask you?
The rocket has 4 of them, excluding the motor mount. All mount onto the BT50H core tube:
Numbers indicate order of attachment. The red arrows point to 5055 rings that attach the BT55 midsection. The blue arrows point to the two rings that bookend the warp core, and support a transition. All are 1/8" plywood. I really like plywood centering rings, find them easy to work with, strong, and don't weigh much. The downside is that their fit is not always quite right. In this case, the two 5055 rings were a bit small in the outer edge, and so were sloppy in the BT55. I fixed that by gluing a strip of copy paper around the circumference of each ring, and then sanding until the fit was nice and snug. Perfect.
I also realized that it was stupid to purchase rings specifically for heavy-walled BT50. It's so easy to just sand the inside of the rings to expand the diameter just a tad; I should have just bought all BT50 rings and sanded as necessary. Oh well. The ones I ended up using here were actually BT50 rings, sanded out until the fit was just the right snugness.
Anyway, ring 1: I was really paranoid about getting the warp core bookends exactly straight, because they'd be visible and also needed to mate with the transition shroud perfectly. So, in addition to drawing a placement circle around the tube, I dry-fit the BT55 to the front and put the transition on. After positioning the ring on the glue I slid the transition on to make sure fit was correct. In the end that wasn't really necessary; first, I got the position of the ring sufficiently correct just using the placement circle; second, by the time I slide the transition on the TBII had grabbed pretty tight and left me with no way to to any adjustments. Fortunately, everything went smoothly.
Here everything is staged for gluing:
After that one was set, I glued on #2, right up against it. It didn't need to be perfectly flush, but it was easy to just push it as far as it would go. #3 was glued a hair below the end of the tube, with just enough space for a bit of fillet. Here are the first three rings, installed:
The launch lug "pocket" was aligned with a lug line I made on the tube:
Cruising along, so far so good. (<-- this is usually a signal that trouble is coming)
I dry-fitted ring #4, starting by aligning the lug pocket to the same line as shown above. Then I saw this:
What you are looking at is one mark being misaligned at the same time another mark (the lug pocket) *is* aligned. In fact, on the second ring, *most* of the marks were not aligned to the body tube marks. This was a puzzle; I thought I had checked all this, and anyway how could everything be off like this? I double-checked with my little template and it seemed like I had marked the ring correctly. What the heck?
Well, the answer seems to be that my little template was inaccurate. After all the times I used scripts to generate my various templates, I did that one by hand in a drawing program, doing it in a way that I *thought* was guaranteed to be accurate. Apparently not! After pondering this situation for a little while, I concluded there was really only one thing to do. The lug pocket on ring 4 *needed* to align with the pocket on ring 1. So I positioned ring 4 with the pocket properly aligned, and then re-marked *both* rings so that all marks were in line with each other. The end result of this will be fine but imperfect; the lug will not be perfectly centered between the two fins. No biggie, and lesson learned: double-check all home-made templates before using them!
Now I could glue on ring 4. Once again I got the position correct just as time ran out with the TBII.
At this point I realized that I could do something I've been wanting to do since I first planning this build months and months ago: test the launch lug mounting. I sanded the two ends of the lug piece until it was the correct length, and then slid it into place:
Frankly, the fit is amazing; each pocket holds the basswood piece very snugly, and the length is just right so the two ends slide in with a nice bit of friction. To me it feels quite solid; for the first time I truly feel that this cockamamie scheme will work.
I might have just a bit of work to do to make sure that the lug is sitting level across the two rings; in that picture it looks like the left side is a bit lower, but I don't know if that's an illusion of the picture or not.
In this picture you can see the paper-covered surfaces of the two BT5055 rings on the right.
What is more fun than talking about centering rings, I ask you?
The rocket has 4 of them, excluding the motor mount. All mount onto the BT50H core tube:
Numbers indicate order of attachment. The red arrows point to 5055 rings that attach the BT55 midsection. The blue arrows point to the two rings that bookend the warp core, and support a transition. All are 1/8" plywood. I really like plywood centering rings, find them easy to work with, strong, and don't weigh much. The downside is that their fit is not always quite right. In this case, the two 5055 rings were a bit small in the outer edge, and so were sloppy in the BT55. I fixed that by gluing a strip of copy paper around the circumference of each ring, and then sanding until the fit was nice and snug. Perfect.
I also realized that it was stupid to purchase rings specifically for heavy-walled BT50. It's so easy to just sand the inside of the rings to expand the diameter just a tad; I should have just bought all BT50 rings and sanded as necessary. Oh well. The ones I ended up using here were actually BT50 rings, sanded out until the fit was just the right snugness.
Anyway, ring 1: I was really paranoid about getting the warp core bookends exactly straight, because they'd be visible and also needed to mate with the transition shroud perfectly. So, in addition to drawing a placement circle around the tube, I dry-fit the BT55 to the front and put the transition on. After positioning the ring on the glue I slid the transition on to make sure fit was correct. In the end that wasn't really necessary; first, I got the position of the ring sufficiently correct just using the placement circle; second, by the time I slide the transition on the TBII had grabbed pretty tight and left me with no way to to any adjustments. Fortunately, everything went smoothly.
Here everything is staged for gluing:
After that one was set, I glued on #2, right up against it. It didn't need to be perfectly flush, but it was easy to just push it as far as it would go. #3 was glued a hair below the end of the tube, with just enough space for a bit of fillet. Here are the first three rings, installed:
The launch lug "pocket" was aligned with a lug line I made on the tube:
Cruising along, so far so good. (<-- this is usually a signal that trouble is coming)
I dry-fitted ring #4, starting by aligning the lug pocket to the same line as shown above. Then I saw this:
What you are looking at is one mark being misaligned at the same time another mark (the lug pocket) *is* aligned. In fact, on the second ring, *most* of the marks were not aligned to the body tube marks. This was a puzzle; I thought I had checked all this, and anyway how could everything be off like this? I double-checked with my little template and it seemed like I had marked the ring correctly. What the heck?
Well, the answer seems to be that my little template was inaccurate. After all the times I used scripts to generate my various templates, I did that one by hand in a drawing program, doing it in a way that I *thought* was guaranteed to be accurate. Apparently not! After pondering this situation for a little while, I concluded there was really only one thing to do. The lug pocket on ring 4 *needed* to align with the pocket on ring 1. So I positioned ring 4 with the pocket properly aligned, and then re-marked *both* rings so that all marks were in line with each other. The end result of this will be fine but imperfect; the lug will not be perfectly centered between the two fins. No biggie, and lesson learned: double-check all home-made templates before using them!
Now I could glue on ring 4. Once again I got the position correct just as time ran out with the TBII.
At this point I realized that I could do something I've been wanting to do since I first planning this build months and months ago: test the launch lug mounting. I sanded the two ends of the lug piece until it was the correct length, and then slid it into place:
Frankly, the fit is amazing; each pocket holds the basswood piece very snugly, and the length is just right so the two ends slide in with a nice bit of friction. To me it feels quite solid; for the first time I truly feel that this cockamamie scheme will work.
I might have just a bit of work to do to make sure that the lug is sitting level across the two rings; in that picture it looks like the left side is a bit lower, but I don't know if that's an illusion of the picture or not.
In this picture you can see the paper-covered surfaces of the two BT5055 rings on the right.
Midsection
One of the many mundane issues I spent too much time thinking about on this build was the shock cord attachment. It would make complete sense to attach the Kevlar to the forward centering ring, but then the Kevlar wouldn't be nearly long enough to pull back through the back of the rocket to attach the elastic. And I prefer when possible to keep the Kevlar inside the body tube.
I eventually concluded that in a BT55, if the Kevlar loop came close to the end of the body tube, I could thread the elastic through it with tweezers without too much trouble. And so I attached the Kevlar around the first ring, and tied the loop to stay just inside the tube. I dry-fit the tube on many times until I got the loop placement just right.
Next I glued on the BT55. I put a ring of glue around the second ring (up against the larger 3rd ring) and a ring of glue inside the body tube about an inch up, and then slide the tube on quickly and forcefully. It settled in very nicely. The glue at the end squeegeed out and I smoothed it into a fillet, and looking down into the BT55 showed a nice ring of glue got pushed out there as well:
So this tube is well-glued. The very tight centering rings helped ensure that the tube is on straight (i.e., there's no play *at all*), which is good because there's almost no other way to verify proper alignment on this design.
Finally, I glued on the transition and smoothed out all the seams with some CWF, and this section is finished:
The shroud seam is positioned in line with the launch lug, so it should be out of sight most of the time. It's smoothed out fairly well, but probably will still be visible under the gloss paint.
One of the many mundane issues I spent too much time thinking about on this build was the shock cord attachment. It would make complete sense to attach the Kevlar to the forward centering ring, but then the Kevlar wouldn't be nearly long enough to pull back through the back of the rocket to attach the elastic. And I prefer when possible to keep the Kevlar inside the body tube.
I eventually concluded that in a BT55, if the Kevlar loop came close to the end of the body tube, I could thread the elastic through it with tweezers without too much trouble. And so I attached the Kevlar around the first ring, and tied the loop to stay just inside the tube. I dry-fit the tube on many times until I got the loop placement just right.
Next I glued on the BT55. I put a ring of glue around the second ring (up against the larger 3rd ring) and a ring of glue inside the body tube about an inch up, and then slide the tube on quickly and forcefully. It settled in very nicely. The glue at the end squeegeed out and I smoothed it into a fillet, and looking down into the BT55 showed a nice ring of glue got pushed out there as well:
So this tube is well-glued. The very tight centering rings helped ensure that the tube is on straight (i.e., there's no play *at all*), which is good because there's almost no other way to verify proper alignment on this design.
Finally, I glued on the transition and smoothed out all the seams with some CWF, and this section is finished:
The shroud seam is positioned in line with the launch lug, so it should be out of sight most of the time. It's smoothed out fairly well, but probably will still be visible under the gloss paint.
Finishing the Warp Core (for now)
I installed the rear transition; really got a good fit and the whole thing looks great. I noticed, though, some dubious alignment between the motor tube attachment markings on the shroud and the cage piece markings on the rear ring. And so I endeavored to update my markings on the rings yet again, this time with a fin marking guide:
Then I put some nice new dark markings on the rings:
Those rings will eventually be painted black, so I'm not concerned about covering those marks. The reason for the need for accurate marks is that I'll need to mask those areas when painting, to preserve clean glue points for the cage pieces, and they must be perfectly aligned between the two rings. I should have done the whole thing with the marking guide like this in the first place; my little printed template actually just caused me trouble in the end.
I applied a nice coat of CA to both transitions and sanded them smooth. My current preferred technique for coating anything in CA (other than nose cones) is to apply some *thin* CA directly onto a cotton swab (I get the whole thing pretty wet but not dripping) and then wipe. I like that the thin CA spreads more easily and really soaks into the surface. Applying just a few drops directly onto the swab avoids mess (although obviously I protect the surface underneath).
On the rear shroud, I left a safe area around where the warp motor tubes would be attaching. You can see the lighter area around the outline where there is no CA.
Finally, just for laughs, I applied CWF to the warp core itself to smooth it out, and the core is done until the very end of the build.
Doesn't look like much yet given level of effort, but it should start getting more photogenic soon.
I installed the rear transition; really got a good fit and the whole thing looks great. I noticed, though, some dubious alignment between the motor tube attachment markings on the shroud and the cage piece markings on the rear ring. And so I endeavored to update my markings on the rings yet again, this time with a fin marking guide:
Then I put some nice new dark markings on the rings:
Those rings will eventually be painted black, so I'm not concerned about covering those marks. The reason for the need for accurate marks is that I'll need to mask those areas when painting, to preserve clean glue points for the cage pieces, and they must be perfectly aligned between the two rings. I should have done the whole thing with the marking guide like this in the first place; my little printed template actually just caused me trouble in the end.
I applied a nice coat of CA to both transitions and sanded them smooth. My current preferred technique for coating anything in CA (other than nose cones) is to apply some *thin* CA directly onto a cotton swab (I get the whole thing pretty wet but not dripping) and then wipe. I like that the thin CA spreads more easily and really soaks into the surface. Applying just a few drops directly onto the swab avoids mess (although obviously I protect the surface underneath).
On the rear shroud, I left a safe area around where the warp motor tubes would be attaching. You can see the lighter area around the outline where there is no CA.
Finally, just for laughs, I applied CWF to the warp core itself to smooth it out, and the core is done until the very end of the build.
Doesn't look like much yet given level of effort, but it should start getting more photogenic soon.
Coming along nicely. If you're really OCD about shroud and nozzle seams, you can consider a glue strip behind the seam instead of an overlapping glue tab. Both sides across the seam are level with each other, less filling needed. For future consideration.
Tally ho.
Tally ho.
I tried that once in the past and really had trouble with it; it's been a while but if I recall correctly I couldn't get the bend of the tab to match the rest of the shroud, and ended up with mild creasing at either end of the tab. I should probably go back and try it again now that I've had a lot more practice. In the meantime, I can usually hide the seam pretty well, either by CA+sanding+CWF or by simply putting it underneath something. Always room to get better in that area though.
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I think Chris Mitchelsson (HCMBANJO) in one of his blogs talked about doubling his transitions (draw and cut out two and glue them together.) Added strength.
Tagging along with the BARgeezer above, you could use scotch tape to fix the adjacent seams of the first one, and glue the second one on with the seam in a different orientation on top of the first.
(Acknowledging of course that this suggestion is coming me, from someone who frequently doesn’t even paint his rockets!)
For whatever reason I've not felt the need to do this, and I'm just using 65 lb card stock. Certainly a double layer "super-shroud" would be incredibly strong, but it hasn't seemed necessary at least on most of the ones I've done so far. If I squeeze my transitions I can dent them, but to normal gentle handling they feel pretty hard. Maybe I just haven't flown any of these enough times to experience flight damage.
Changing the orientation of the seam is definitely required when doing a supershroud, you don't want the seams stacked whichever way you do them.
The main shroud lesson I learned on this rocket is not to glue the small end, at least not with TBII, until after the shroud is in place. I had to manhandle the front shroud a bit to slide it over the glue, and that created a few defects in the finished product. Just glue the big end, slide it on, then apply a small exterior glue bead/fillet to seal up the front.
This suggestion is both silly and seriously the best way to do it: sand bevels into the paper edges so that as they overlap the combined thickness stays steady.
Not so silly; you can actually bevel off the paper edge on the outside pretty effectively if the overlap tab has been well-treated with CA, and that's what I normally do (@Gary Byrum uses this approach as well I believe). On the inside, it's somewhere between difficult and impossible to do that, but it usually doesn't matter so much inside anyway.
At the size I normally work, I find most shrouds pretty easy to do at this point; for this rocket I used the first two I made. I haven't tried to do anything like a Dr. Zooch where you need to make tiny tweezer shrouds, and making very long skinny shrouds where the paper need to bend to a small radius have defeated me (see: Ragnarok Orbital Interceptor).
With what I was thinking, there's no difference between beveling the inside and the outside. Start with the flat piece of paper, cut out but not rolled. Bevel the top on one end (right edge in the picture, what will be the inside of the joint) and the bottom of the other end.
When I wrote "silly" I was thinking about beveling the edges of 20 or 24 lb. paper. If you're using 65 lb. cardstock (your previous post ninja'ed mine) then maybe it's not so silly after all.
When I wrote "silly" I was thinking about beveling the edges of 20 or 24 lb. paper. If you're using 65 lb. cardstock (your previous post ninja'ed mine) then maybe it's not so silly after all.
After the wood glue dries, I like to paint with thin CA all of my paper anythings: nozzles, fairings, shrouds, transitions. Gives them the consistency and toughness of thin styrene.
Also usually paint with CA the long pointy balsa nose cones, last inch or so. Like the WAC Corporal and Nike Smoke. Cuz I always seem to knock them over and break the tip even before first launch. Doesn't make them bulletproof, but less prone to breakage.
Also usually paint with CA the long pointy balsa nose cones, last inch or so. Like the WAC Corporal and Nike Smoke. Cuz I always seem to knock them over and break the tip even before first launch. Doesn't make them bulletproof, but less prone to breakage.
But styrene is always thin; its viscosity is slightly lower than water's.
Oh, wait a minute, did you mean polystyrene? My bad.
More precisely, vacuformed styrene.
Well, vacuformed polystyrene. Styrene is a volatile, toxic, carcinogenic, flammable liquid; they only thing it can be vacuformed into is a toxic, carcinogenic, explosive vapor.
Joe,
You need to educate these guys:
You need to educate these guys:
Well, someone needs to.
This is certainly way off topic, but Wikipedia would seem to support Joe here: https://en.m.wikipedia.org/wiki/Styrene.
I wonder if calling plastic “styrene” is just an incorrect colloquialism of sorts. I feel like I’ve heard it used in that way, but now I don’t know which plastic that would be referring to. Could’ve been either polystyrene (Most likely) or ABS I reckon. What Plastruct means on that bottle is a darn good question (probably polystyrene).
I wonder if calling plastic “styrene” is just an incorrect colloquialism of sorts. I feel like I’ve heard it used in that way, but now I don’t know which plastic that would be referring to. Could’ve been either polystyrene (Most likely) or ABS I reckon. What Plastruct means on that bottle is a darn good question (probably polystyrene).
I assume it's polystyrene, but I wonder why it's common only with this one material. You never hear of 3D printing with lactic acid, or storing your leftovers in ethylene containers. "My water pipes are all vinyl chloride."
Back to the build! Warp tube fitting, again
Advance-prepping everything can lead you astray, e.g.:
So now I had to trim something like a millimeter off each of the tubes. Fortunately, having acquired a clue since last time I cut these things, I taped the piece onto an old spend 13mm motor, using that to support the BT5 and act as a cutting surface. It is rock hard, way better than even a piece of coupler. Holy crap, now I am really pissed that I was too stupid to think of this the first time. Cutting was super easy and quick and clean and accurate.
My thoughts immediately went to cutting all new pieces, because I could do much better now. Alas, I know of no easy way to acquire new BT5 quickly enough. As far as I can tell, Hobby Lobby doesn't have any kits with a significant amount of BT5 in them for me to cannibalize, and certainly there isn't any such thing as a hobby shop near me that actually carries parts. I think I have enough on-hand for one new piece; perhaps I'll cut that one and just replace the worst of my three existing ones.
Advance-prepping everything can lead you astray, e.g.:
So now I had to trim something like a millimeter off each of the tubes. Fortunately, having acquired a clue since last time I cut these things, I taped the piece onto an old spend 13mm motor, using that to support the BT5 and act as a cutting surface. It is rock hard, way better than even a piece of coupler. Holy crap, now I am really pissed that I was too stupid to think of this the first time. Cutting was super easy and quick and clean and accurate.
My thoughts immediately went to cutting all new pieces, because I could do much better now. Alas, I know of no easy way to acquire new BT5 quickly enough. As far as I can tell, Hobby Lobby doesn't have any kits with a significant amount of BT5 in them for me to cannibalize, and certainly there isn't any such thing as a hobby shop near me that actually carries parts. I think I have enough on-hand for one new piece; perhaps I'll cut that one and just replace the worst of my three existing ones.
OK, it looks like I actually have enough BT5 for two new warp tube pieces. Gonna give it a go. I have taped together 3 13mm motor casings to act a cutting support for the tube.
