1 Attachment(s)
Here's A Hastily Modeled Computer Rendering Of What I Was Alluding To
This is a quick and general CAD rendering of what I hope will be the final iteration of my Automatic-Resin-Mixing Vat.
The dimensions of the vat itself remain basically the same. The only difference are the input and output flow ports.
These will be easily removable and allow for the adjustment of the angle-of-flow. They are designed to slide right into place.
The exact placement within the vat corner walls will be adjusted as soon as I take delivery of the HDPE plastic material I've ordered.
In the mean time I'll continue to run my flow tests with the 3D printed Automatic-Resin-Mixing vats I now have to work with. I'll be uploading those flow tests next week some time.
Incidentally, I went ahead and ordered that slightly more powerful Peristaltic Pump I mentioned in one of my previous post.
I'm starting to see the light at the end of the tunnel for this particular project. I really believe it's going to work out well as a resin mixing tool that doesn't need me to constantly monitor it as my prints are under way.
Please note; this is just a computer rendering. The final vat may have some very slight cosmetic changes but the purpose and the function will be the same.
HollowPoint
All Of The Parts I've Ordered For This Project Have Finally Arrived
My CNC mill has been sitting idle for a little over a year since delving into 3D printing.
What this means for me is that I've just about had to re-learn how to use my mill and the CAM Software that I use to convert my CAD models to the G-Code needed to be able to machine them into existence.
I just about have it all done. I'll be ready to do my machining next week.
I bought just enough HDPE plastic to machine two Automatic-Resin-Mixing vat prototypes. This means I have only enough room to screw up once and still get a good usable resin vat.
I'll also be printing one last vat with my filament 3D printer. I still want to experiment with letting one of my filament printed vats sit full of resin overnight. I want to see with my own eyes exactly if or how the 3D print resin affects the resin vat. The down side to this may be that I'll be ruining some resin if that experiment does go south on me but, I just can't wrap my head around how liquid resin could ruin a solid PETG plastic resin vat. The only way to know for sure is to try it.
I've been told by "Experts" that a 3D printed resin vat will not hold up when subjected to direct contact with liquid un-cured resin. If it fails, then those experts will be able to gloat and tell me, "I Told You So." If it succeeds, well, good. That's what I was hoping for all along.
I know my title states that all my ordered parts have come in; I take that back. I'm still waiting for the silicone rubber gasket material I need to be able to fill my vats with resin so they won't leak; then I can do the testing on the 3D printed vats.
I'll be back with another update next week.
HollowPoint
I'll Be Cutting Alot Of Air Tomorrow
Just to clarify; I'm not meaning to say that I'll be throwing alot of farts tomorrow. I got all my milling tool paths setup in my CAM software. The computer simulations all looked good but, I want to run through all the tool paths on the mill by letting it go through all the motions without actually cutting anything.
It's been a while since I programmed my mill or machined anything with it so, the pucker-factor will be high when I actually do the cutting. I anticipate my little CNC mill will be spitting out strands of black HDPE plastic spaghetti the likes of which I've never seen before on any of my projects. I've never machined plastics like this before.
I'm happy to report that I got that last 3D filament printed Automatic-Resin-Mixing prototype finished up. It turned out real well too; just like the previous prints. I also made the four little easily-installed, easily-removable and easily-adjustable input and output resin-flow ports.
I was running low on 1/2" aluminum rod so I made those flow-ports in such a way that I could test them with both the 1/4" inside diameter tubing used on the slightly larger peristaltic pump I recently ordered and the smaller 1/8" inside diameter tubing on that slightly smaller pump I had previously ordered.
Through a stroke of Sheer-Dumb-Luck, I found that the slightly larger pump did very well without having to go through the hassles of wiring it with the previously purchased little potentiometer in order to control the flow of the fluid I'd be pumping through it. That was relief because, there are two things that really I suck at. One is mathematics and the other is electronics.
The rubber gasket material I ordered also finally showed up so I was able to completely assemble my newly 3D-filament printed Automatic-Resin-Mixing vat. I filled it with water just to see if it would leak, and to do some quick tests with the new pump. So far so good. I'm letting it sit over night filled with water just to confirm that it doesn't leak
Once I confirm that it's not going to leak while holding a less viscous liquid like water, I'm sure it will do fine holding a thicker liquid like 3D print resin. I'll then fill that same 3D-filament printed resin vat with some 3D print resin and let it sit for a day or two. I'm really curious to see if that non-cured liquid 3D print resin will do any kind of damage to that PETG filament printed vat.
I mentioned before that I was told by the "Experts" that pouring liquid 3D print resin into a 3D printed vat or container would have detrimental effects on those 3D printed containers; or in my case, resin vats. These "Experts" know more about this kind of stuff than I do but I'm holding out hope that they have never personally done such a thing themselves. They were just offering their advice based on what they'd read and not actually on what they'd ever done to prove their claims.
Heck, even if these "Experts" are right and my 3D printed vat melts away into oblivion, I'd be real happy just to have that 3D printed vat hold up for two or three print sessions before it showed signs of failing or succumbing to whatever negative effects that 3D print resin might impart.
That would be more than enough time for me to print up a couple of batches of single cavity bullets molds. This would then allow me to prove my own theory that, thoroughly mixing the added porcelain powder to the factory formulation of the resin I use to print my bullet molds will in fact increase the heat resistance of the molds; and thereby increase the service life of the 3D printed bullet molds.
I don't want to get ahead of myself though. I'll just have to take it one step at a time. I'll try to take some photos of this latest 3D printed Automatic-Resin-Mixing vat within the next couple of days so I can show you all where I'm at with this project. Even if the 3D printed vat doesn't work out, I know now that the HDPE plastic vats that I'll be machining in the next day or two will work out when subjected to prolonged contact with 3D print resin.
I'll be back with more updates later.
HollowPoint
The Torture Testing Of My 3D Printed Automatic-Resin-Mixing Vat Has Begun
This is just a short video update to show you all where I'm at with this Automatic-Resin-Mixing Vat Project.
As always, my video quality is very low so again I'll be asking you to pause the video whenever you see any kind of text coming on screen. This text is generally something that I screwed up during my ramblings or something I forgot to include.
In addition to this PETG filament 3D printed prototype resin vat, I'll also be machining two additional vats out of HDPE plastic within the next couple of days. That way if my torture tests fail to produce the desired results I'll still have a couple of usable Automatic-Resin-Mixing Vats to work with.
There is an embarrassing side note to all of this. It's something that I had not taken into consideration in the designing, machining or printing of my resin vats. I had not considered the fact that with the larger inside diameter hoses I'll be using to pump my resin into and out-of my Automatic-Resin-Mixing Vats, this means that the four or five ounces of resin I have left to work with will not be enough to actually print my next batch of single cavity bullet molds.
Initially I'm more than sure that everything would work as designed but, even if I put all four or five ounces of the resin I have left into the vat, enough of it would be sucked out of the vat in fairly short order that I'm afraid I'd run the risk sucking in air and blowing out bubbles on
the input flow end. I can't run the risk of bubbles getting into my resin mix. That would be a terrible mistake to make.
If I were printing another batch of single cavity bullet molds without the Automatic-Resin-Mixing Vat as before, I'd have more than enough to print three more bullet molds.
This just means that I'll have to save up some more nickles and dimes to buy another full bottle of the High Heat Resistant 3D print Resin before I can actually print more bullet molds. With the thoroughly mixed resin that this Automatic-Resin-Mixing vat was designed to deliver, (minus the air bubbles) there's a far, far better chance of ultimate success.
I think it's still going to work out for me because I still have the HDPE plastic vats to machine and test, followed by the fabrication of four more input and output flow ports and possibly having to fabricate a couple of the small rectangular metal frames that fit on the underside of each resin vat.
The 3D printed frames I'm using now seem to be working fine but I'd feel more comfortable with ones made of a more rigid material than PETG filament.
By that time I should have the money saved up to buy another bottle of resin. I'm inching my way toward the finish line. I can't wait to print out that next batch of bullet molds. I'm optimistic about the greater durability of my next set of those prototype bullet molds now that I've come up with a way to keep my resin thoroughly mixed.
In the end, I believe that all of this will have been worth while. Not just for me but for any 3D-Print-Nerd that happens to be a bullet caster or mold maker who dreams of 3D printing molds that are able to cast certain types of metals; metals that were formerly out of reach of the 3D resin printer.
Thanks for sticking around for as long as you have. I'll be back to show you all how the machined HDPE plastic Automatic-Resin-Mixing Vats turned out.
Even though it's outside the scope of a couple of the 3D resin print groups that are following this project, I may video record some short snippets of the machining process of those HDPE resin vats too. Why? Because there's more to resin 3D printing than just resin 3D printing.
I'll be back.
https://youtu.be/Amv5r0brkcg
Day Two Of My Automatic-Resin-Mixing Vat Torture Testing
So far so good.
Neither the vat itself or any of the pieces of different types of materials I've left emersed in my 3D resin filled vat show any kind of deterioration or damage. In fact, at this point they all appear to be in no different condition than they were a couple of days ago when I started this testing.
I contacted those "Experts" that had cautioned me about my 3D resin vats not holding up and I got a sense that they were sort of back-peddling in regard to what they had told me.
As I had kind of suspected; none of the three "Experts" I had consulted about this had ever really tried it themselves. Their words of caution were based mainly on book learning more than actual hands-on experience. I'm not knocking them. I only wish I had as much book learning experience as they do but, on the other hand, if I did have this kind book learning under my belt I most likely would not have even tried this to begin with. Sometimes ignorance really is bliss.
So what does this mean in the grand scheme of this project?
Well, I still plan on finishing up the machining of my HDPE prototype vats and using them first but, what this really means is that now I can simply 3D print my Automatic-Resin-Mixing vats as needed; and I can be confident in the fact that they will not melt away or deteriorate into oblivion in short order as was indicated by the "Experts."
Regarding the HDPE vats that I would be machining yesterday:
I did my "Air-Cutting" tests, and everything went exactly as my computer simulations showed that they would BUT, when I went to do the actual cutting on the part, I could immediately tell that something wasn't right cause my end mill was cutting into parts of my HDPE block that it was not supposed to cut into. Fortunately, I caught it in time so as not to ruin a perfectly good piece of HDPE plastic.
Have you ever heard the saying, "Measure Twice, Cut Once?" Well, I did this. I always to this with my projects so this was not to blame for my end mill shaving off parts of my plastic block that it was not supposed to. So this kind of left me scratching my head.
Upon careful inspection I found that the culprit was caused by me "Assuming." When I had cut my blocks of HDPE to size on my table saw, I had "Assumed" that the blade on my saw was at a perfect ninety-degree straight up and down angle to my work piece. Unbeknownst to me it was tilted just enough to result in one side of my HDPE block coming out wider on the top of the block than on the bottom of the block.
So, when I placed it on the mill for machining, I had placed it with the thinner side up. This meant that when I indexed it before cutting, my end mill would naturally be off by the same amount that my crooked saw blade (my "Assuming") had left me with.
Since I caught it in time, I was able to just trim down and square up my block of HDPE and salvage this block of plastic. This also meant that I had to go back into my CAD and CAM software and redo my models and my tool paths to compensate for the slight dimensional changes I had to make to salvage my blocks of HDPE.
I think I got it under control now. Even if I still manage to ruin both blocks of my HDPE vat workpieces, I can still fall back on the fact that if I do manage to screw this up I can simply 3D print them now.
There's light at the end of the tunnel. I can see it more clearly now.
HollowPoint
1 Attachment(s)
All Of My Automatic-Resin-Mixing Vat Components Are Finally Done
All of the components for my Automatic-Resin-Mixing Vat are now completed.
I've ordered some additional tubing for my 1/4" Peristaltic pump. The tubing I had previously ordered was a bit too stiff for me to easily thread in and around the tiny work area within my small resin printer.
The new tubing is some of that silicone tubing. It's medical and industrial grade so I'm sure it will hold up well when subjected to extended contact with 3D print resin. My ongoing torture testing has confirmed that it would. The 1/8" tubing I was using for my 1/8" Peristaltic pump was included in my torture testing. It seems to be holding up real well so I see no reason that this incoming 1/4" silicone tubing won't work out for me.
I'll also have to make some slight mods to my printer as well. These mods will be in the form of simply altering the height of the two small vat-anchoring points.
My 3D printed Automatic-Resin-Mixing Vat is 1-1/2" tall. The factory Vat and the HDPE machined vat is 1-1/16" tall. It's a simple modification that will allow me to use either vat by simply adjusting the height of the little vat-anchoring-points up or down.
There is also a small 3D printed housing that I'll have to print for holding my pump in place within or outside of the 3D resin printer but, all of these have already been modeled and will soon be ready to print as well. I just have to decide if I want to place the pump inside or outside of my printer.
It's all coming together. I'll have the money I need to buy another bottle of the High-Heat-Resistant resin within the next few days.
Just to give you all an idea where I'm at with those Flow-Ports, here's a screen shot of the Flow-Ports as they'll be oriented on my filament printer's build plate.
You know: The more I get into this 3D printing stuff the more I'm thinking of selling my CNC mill and just buying a smaller verticle mill instead. It seems that for the kind of projects I've been doing and plan on doing in the future, I can just as easily do them on my 3D printers. Having a small or mid-sized verticle mill will still allow me to do some basic milling when ever I need to.
I'll be back when I get farther along.
HollowPoint
4 Attachment(s)
Now I Wait For The Stars To Align
I thought I'd gotten everything done that needed doing.
I also thought that since I live in Arizona I would have no need for an inline heater to keep my resin heated to the optimum temperature for printing with my newly finished Automatic-Resin-Mixing Vats.
It appears that the weather here in Arizona has conspired against me and we've hit a cold snap.
My printer runs in the back storage room where there is no air conditioning or heating. This means that if the weather continues to stay as cool as it's gotten then I'll also have to order the components to build a resin heating setup.
It's nothing that's really hard to do; it's just that it adds to the time it will take me to finally be ready to print some more bullet molds.
The original design of my Automatic-Resin-Mixing vat had already included the option to integrate an inline heating element.
The components I need to print in order to facilitate this inline resin heating pod had already been modeled. It's just that I didn't think I'd ever need to use it. Looks like I was wrong. (again)
I got just about everything else ready to go. The bracket that secures my Peristaltic Pump to the outside-back of my resin printer is done. The Pump-Housing has been printed. The tubing I need and connectors are all ready to go too.
Some of the money that was to be used to buy another bottle of resin will now be diverted to buy the couple of components that will make up my inline resin heater/reservoir.
Below is another CAD rendering of some of the components that I've modeled and printed and some (the smaller components) that I'll be printing in the next couple of days.
I've also included some photos of the partially assembled and installed pump-bracket, pump-housing and other components as well as a shot of the four finished Automatic-Resin-Mixing vats I have to work with once I'm ready to do some actual printing.
Now I just have to wait for my financial stars to align again so that I can get back on track for buying that bottle of resin. I have to mention here that this is just a hobby for me so I don't mind saving up expendable-income to do this kind of stuff. When it comes to budget constraints I like to be meticulous about it. I guess one could even say I'm anal-retentive about it.
Still, once I get rolling on a project I hate having to wait while I stick to my financial guns about all of this.
I'll be back with more updates as I get farther along.
HollowPoint
I Found The Money To Move Forward With This Project
It was right under my nose all this time.
I have a Spare-Change-Jar on my dresser that I put all my spare change in each time I empty out my pockets.
I generally use this spare change at the end of each year to buy my new hunting and fishing license. It's like an annual ritual that never fails me.
Just out of curiosity I thought I'd check and see just how much spare change I had accumulated this year. Wow: it was enough to pay for my fifty-seven-dollar Hunting/Fishing Combination license with enough left over to buy the Heating element and controller I need to complete the Automatic-Resin-Mixing Vat project.
I'm back in business. With any luck at all I'll be able to do my next single cavity bullet mold print next week some time. Hallelujah! Things are looking up.
In case any of you were wondering; if there had only been enough spare change for one or the other, I would have spent it on the hunting and fishing license for sure.
HollowPoint
2 Attachment(s)
Moving Along At A Snail's Pace
I finally got around to taking some photos of some of the alterations I've made to my 3D resin printer in order to accommodate the taller Automatic-Resin-Mixing vats that I printed with my filament 3D printer and that I milled out of HDPE.
Right now it looks like something out of Frankenstein's laboratory or, like I mentioned in my previous post; "It looks like a Jr. High-School science experiment gone awry."
No matter. I just want to get it to work for now. I'll deal with the aesthetics later.
I did some last-minute fitment tests with everything hooked up so I could raise and lower the build plate to see what kind of clearances I was getting all the way around.
I'm so happy I did these tests because I was fully prepared to do my first prints without ever checking my clearances.
By slowly lowering the build plate I found that I had failed to account for the thickness of the arm that the build plate attaches to.
My build plate would not go all the way down to the home-position. It stopped about a quarter of an inch before reaching the bottom of its movement because it was hitting the top of the rear-most vat wall.
I can easily mill off enough material from the raising and lowering-arm but, I don't want to make any kind of irreversible alterations to my printer.
Up to now, all the mods I've done to accommodate the new Automatic-Mixing-Vat can be easily reversed. At the very least, those mods can be covered over to make them look like they're supposed to be there.
What I ended up doing instead was milling a notch on the rear-most wall of the vat to allow my build plate to be able to travel all the way down to the home-position. Unfortunately, doing this means that I will no longer have a new vat that is capable of holding more resin than the factory vat.
This just means that it was a good idea to incorporate an additional resin reservoir to hold the additional resin I'd need to keep the vat filled high enough throughout the print session for the pump not to start sucking in air and blowing bubbles into the vat.
In some of my recent posts I made it a point to mention more or less, the estimated time before I'd finally get to the actual print session to print out my next batch of single cavity bullet molds.
I'm going to have to stop doing that because it seems that each time I throw out a timeline, something comes up to throw a monkey-wrench in the works. It's like I put the whammy on myself or my project by stating when I'll be printing another bullet mold.
At this point I just want to say that this project IS moving forward. I'm just reluctant to give any set date when I'll be printing up another batch of bullet molds; other than to say, Soon; hopefully very soon. I've got everything ready to go now, except for the free time to do it in.
UPDATE: Wouldn't you know it? After I went to the trouble of milling that slot on the rear-most wall of my 3D printed Vat in order to get the clearance I needed for my Build-Plate to reach its Home-Position, I discovered that I could have simply lengthened the little metal trigger that trips the Homing/Limit-Switch just before the Build-Plate reaches the Home position.
This will require another modification to get the build plate to reach down low enough into the taller Automatic-Resin-Mixing vat to get to the Home-Position. I wish I would have discovered this earlier. It would have kept me from hacking up a perfectly good 3D printed Automatic-Resin-Mixing vat. Now I have to make a couple of easily swapped-out little extension plates.
Imagine if I would have gone ahead and milled off some material on the arm that the Build-Plate attaches to. I'm glad I decided against it. This is what happens when I get into to much of a darn hurry.
Oh well, I have enough filament left on that last roll of PETG filament I bought to print out one more of the taller Automatic-Resin-Mixing vats; then I think I'll be home-free. I've already started that print. It should be done when I wake up tomorrow morning; unless of course, I just put the whammy on myself again.
HollowPoint
3 Attachment(s)
That's What I Get For Being Impatient
My Automatic-Resin-Mixing Vat worked great. It showed absolutely no negative effects by being subjected to either the resin or the pump flow.
Weaving the pump-hoses the way I did left me with plenty of clearance for my Build-Plate to freely move up and down.
The Build-Plate and Limit-Switch mods all worked reliably as intended and yet, the attempted print was a dismal failure.
I did get a partial print out of it but that partial print showed distinct layer lines that were not there when I printed those previous batches of bullet molds.
Some of you may remember me mentioning a mathematical formula for orienting my models on my Build-Plate so as to give the smoothest Flat-Surface-Finish possible for a given 3D resin printer. Well, in my case this just didn't prove to work at all. I'll be reverting back to simply orienting my models flat, directly onto the Build-Plate from here on out.
Using this mathematical formula to calculate the optimum orientation angle meant that I had to use supports in order to hold my models at this specific "Optimum-Angle." I believe it was the combination of this, "Optimum-Angle" using the model-supports, and the fact that I was not able to keep my resin heated to the "Optimum-Heat-Level" that did me in.
Also, I had mentioned in my previous update that I was getting air bubbles because my pump was sucking all the resin out of my inline reservoir and just dumping it into my resin-vat.
During my cleanup of this print debacle, I found out what had really been causing all of those air bubbles. It turns out that one of the 3D filament-printed ports running into my reservoir had cracked at its base underneath the lid of the reservoir and I didn't know about it until I went to clean out the little 4oz reservoir. When I went to unscrew the lid on that reservoir the tip or nipple of one of those ports just broke the rest of the way off.
SO; what this means is that I'll be replacing those particular components with components I'll be fabricating on my metal lathe. It shouldn't take to long but the fact that I'm having to take the long way around is a bit disconcerting.
If I hadn't been so impatient, if I had just taken the time to do a bit more testing; this is one of those, "Coulda-Shoulda-Woulda" moments.
In my own defense, I'd like to repeat that I am not an engineer. I'm not even a machinist. I'm just a chronic Do-It-Yourselfer who tends to learn by trial and error. (mostly error)
At this point I have no doubt it's all going to work once I get it all dialed in. It's the time that it's taking for me to get it dialed in that's driving me nuts.
I'll be taking some time off to get some much-needed home repair stuff out of the way. Recent rains in our area has shown me that my house needs to be re-roofed. I can probably have those new aluminum components made up within a couple of days but even then, it will be a week or so before I can get back on this project to bring it to its' completion.
Here's a photo of the partial print I got this time around. I hope it's not too washed out to show the layer lines I was talking about. I'm also including a closeup of the broken port that broke on my inline resin reservoir and another CAD rendering of the way I had oriented my models on my build-plate in order to give me that, "Optimum-Angle" that didn't work worth a darn.
I shall return.
HollowPoint.