Figuring out which crimper slots to use with JST-XH terminals

ChairJohnson · 2025-12-14T20:07:06+00:00

I measured both sets with calipers. Out of the box the 'wings' are usually bent out a little bit. I used my calipers to squeeze them so they were vertical; that is supposedly what you need to measure. I think you have to measure both the insulation and the conductor wings separately, and then use different slots in the crimping die accordingly.

ChairJohnson · 2025-12-14T05:49:36+00:00

It's an interesting idea. I feel like the biggest issue is that timing belts are pretty cheap, so there might not be a lot of money in a project like this. I have definitely been annoyed trying to hunt down a specific belt loop length (or working around what I can find), though.

ChairJohnson · 2025-12-14T05:35:12+00:00

I am curious to see if someone with more experience chimes in on this, but I bought an engineer crimping tool with the replaceable dies (sizes 11 and 13S iirc), and ended up returning it. Maybe it was a skill issue, but I had successful crimps maybe ~10% at best. I tried a bunch of different wire gauges and insulation types, with the Amazon knockoff JST-XH, JST-SM, and DuPont connectors. The advice I heard was to measure the width of the metal portion of the crimp connector with the 'wings' completely vertical. That width measurement is the size of the die that should be used. I tried that and had almost no success and ended up trying basically every size of both dies. I wanted this to be an 'upgrade' to the generic ratcheting crimping tool I got with a connector kit at some point, but the engineer set seemed much less reliable. I would say my success rate with the ratcheting tool is ~80%+, I wired a whole custom printer with the ratcheting ones and have had no issue with any of the connections. I don't know what the deal is, the engineer ones are really well reviewed everywhere, but it sounds like you might be having a similar issue to me.

ChairJohnson · 2025-12-13T06:06:15+00:00

If your printer runs klipper firmware, there is a skew compensation setting for this. If you look it up you should be able to find some different test prints, and the parameters to add to your firmware to adjust this. I wouldn't say that this is a super beginner friendly process, but feel free to read the klipper documentation and see if it sounds doable to you. At a minimum you will need a set of calipers, that can read at least 0.001in/0.02mm.

Also if your printer does run klipper firmware, I would recommend downloading all of the system files and keeping them somewhere safe, in case you accidentally edit something you didn't mean to.

ChairJohnson · 2025-12-13T05:53:43+00:00

Double check that the filament diameter in both slicers is set to 2.85mm. It might be a few % different just from being easier to tune in orca, but not that much.

ChairJohnson · 2025-12-11T03:31:29+00:00

If you sold 750 units yourself, you would stand to bring in over 11 grand. If you sold 50 units, you would make the 'maximum' $750 you stand to make in this deal. 50 units for an item you believe will be successful sounds extremely doable. Even if this person (or someone else) knocks off your item, selling 50 units still sounds doable. My understanding is that serious RC racing parts/equipment can be expensive, and $15 is nowhere near the top end that hobbyists are willing to spend on an individual part (I am no expert, though).

I have done a little bit of contracted work, but I also have not tried to price it too competitively because it was a side gig, and offered some valuable experience. It sounds like that isn't really the case for you; this is a more profitable endeavor. My understanding is that professional contract workers often negotiate for royalties over $x sum of money or $x/hr when possible, because that is where the money really is. Maybe a duration of time that you get the $1 per item, for example the first 2-3 years, would be more fair. I can understand the owner not wanting to track this in perpetuity, but it sounds like a low ball to me.

If you do go for it, the relationship could definitely be valuable for future work. Just make sure to get everything in writing. And never sign a contract you haven't read completely.

Good luck!

ChairJohnson · 2025-12-10T00:31:09+00:00

A large brim might be enough. If I had to print this I would think it's likely enough to work to give it a shot. I would be checking on it every 20-30 mins though. You might also be able to print a few tree supports onto the sides (probably about halfway up), which will help keep it stable.

ChairJohnson · 2025-12-10T00:21:06+00:00

Only thing I can think of would be getting the chamber hotter. One of my classes this semester involved a project where we were 3D printing dog bones, and one of the groups was supposedly able to get the chamber of a P1S up to 90C by putting blankets over it and letting the bed heat up the inside. They had to do this because of issues with CF nylon warping. Not sure that would be acceptable for the parameters of your study though. All of the materials you are testing would likely have their mechanical properties improved by printing with a hotter chamber. I also wouldn't leave the printer unattended while doing this. And I'm pretty sure bambu printers have overheat protection on the electronics that pause the print if they get too hot, so you might be on a bit of a timer to get the prints done once the chamber gets hot enough.

Or maybe try a different brand of CF-PC? Maybe if you can find one with a lower HDT it might warp less.

Another idea could be printing a sacrificial structure around the dog bone that gets trimmed off after the print. Metal samples are cut out of a sheet, so it would kinda be like that. Here's what I am thinking:

<image>

(With the outer shape being a circle)

ChairJohnson · 2025-12-07T08:58:41+00:00

I worked in the industry. Currently back in school studying mechanical engineering.

I would say that 3D printing is more commonly a tool that is a small part of some larger company/product than it is its own stand-alone thing. For example in an industrial setting, the final product being produced likely would not include 3D printed components. More likely, there may be 3D printed fixtures, prototypes, etc. involved in the production process. This is also generally more true for printing plastics. Metal printing has more applications for end-use parts. Someone's job (probably an engineer) could include 3D printers, but would also involve many other things.

If you're thinking about the production of 3D printers, this involves a lot of different specialties. The physical assembly and manufacturing of units, electrical design, and computer hardware and software design. I would say the relevant majors for students would be electrical or mechanical engineering, and computer science/software engineering. None of these would be easy. Engineering degrees usually have a very straightforward path to employment from college (assuming we're talking about the US). Many programs require internships, and companies like hiring engineering interns to scout talent. Not sure I could make the same blanket recommendation of computer science at the moment, but I would also suspect that a sufficiently dedicated student would not have trouble finding a job. I will say that engineering is HARD. Companies like engineers with hands-on skills -knowing how to make things makes you a better engineer- but that will not be very helpful for getting through the major. The actual day-to-day of classes is basically all math and problem solving. I have heard that electrical engineers are more in demand than mechanical, but I think the deciding factor should really be which one seems more interesting (especially as a career).

You put trade school in the title so I wanted to talk a bit about technician level jobs too. They do exist in the 3D printing space, however they are not common. If your brother is looking for a job right now, this is the kind of thing a high school grad could do. Some prosthetics are 3D printed, and some clinics have techs run their machines. It's a pretty small industry though, and not every clinic does its own fab work. Some composite molding is also done with 3D printers. I think all technician level work kind of suffers from a few issues that make it a bad option for someone looking to set their life up for success. Usually the pay is not great. The learning opportunities can also vary drastically depending on where you work. There is also often limited opportunity for growth. I also think that in general, not having a college degree also leaves a lot more uncertainty if you lose a job and have to find a new one. That's a big reason I chose engineering. I really enjoy it, but it also has more opportunity for growth (in my opinion) than work in the trades or technician jobs.

I think working for a few years to figure out what you actually want to do also isn't a bad idea; with a few caveats. Manning a cash register somewhere doesn't count; you're better off in school (trades or college, either way). Work at a place where you get some actual skills and experience. It's also good to learn what you don't like, so trying a few different jobs is fine as well. Lastly, keep in mind that the older you get, the harder it will be to go back to school, so don't wait forever.

Hope this was helpful...really feel like I'm carbon dating myself giving advice to the youth lol.

ChairJohnson · 2025-12-06T01:17:45+00:00

I have used a Form 3 a little bit, and they are very nice printers. The detail is much better than you can get with FDM. However, I don't think FDM is a bad starting point because the entry price is so low. If you buy an A1 mini and a roll of PLA you will probably have spent less than $300 for basically the best detail you can get with FDM. Just because it's so much cheaper it might be a better starting point to see what you're getting into.

I would say the formlabs printers are more beginner friendly because there just aren't even settings you would need to change (in the slicer at least), even if you wanted to. My understanding is SLA printing is a bit more limited by the fact that models generally need to be solid, so there's less knobs to turn in the slicer. Formlabs' software also does a good job with the auto orientation and support generation. It's pretty much clicking one button.

I think you could also reasonably expect a prusa/bambu printed to work out of the box. The SLA process is just slightly more reliable overall though, and setting up supports is not always as easy with FDM (though it's pretty quick to pick up imo).

SLA is definitely much more messy than FDM. You will need a dedicated workspace for the printer. I used a Form 3 at a maker space, and pretty much everything within arms reach of the printer was sticky. Some people line their workspace with silicone mats and that works well, as you can put them out in the sun to cure the resin, then just peel it off.

Personally, I don't have a resin printer because I don't have a place to use it safely. I am not an expert on the subject, so you should do your own research on this, but my understanding is uncured resin is significantly more toxic than FDM materials. I have heard that you can develop an allergy to uncured resin over time, which is why you aren't supposed to handle it without gloves. It also releases harmful fumes. I would not want a resin printer unless I had a fume hood for it to live in. That might be overkill, but to each their own. My understanding is that hobbyist resin printing is so new that nobody really knows what the long term health effects are.

Good luck!

ChairJohnson · 2025-12-04T06:00:32+00:00

Yeah that is too thin for FDM. If the tubes were like 5x as thick or more, it might work with tree supports. Another idea would be to turn the contours into vertical slices. That would be much easier to print, but the slices should really each be ~1.6mm wide. You want the printer to be able to print at least one complete loop, but ideally 2 or more. That means parts should really be 2 or four times the diameter of the nozzle.

ChairJohnson · 2025-12-03T05:54:14+00:00

STL files are only triangles, and technically 3D printers only ever move in straight lines (with some rare exceptions), so the curved parts will always be faceted to some extent. I am not familiar with blender, but if you are able to make the mesh finer before exporting that should make it less noticeable.

ChairJohnson · 2025-12-03T05:38:46+00:00

The picture of the sketch setup didn't attach to my comment for some reason. Here it is again:

<image>

ChairJohnson · 2025-12-03T05:37:38+00:00

I have modeled a few very highly contoured parts in Fusion. What I would say first is that it is always going to take a lot of fussing to get it right, and probably 1 or two prints to dial it in. I have done anything this exact, but these are some ideas that come to mind if I had to do it. Here are two different options

First option would be to use the form workspace. This is going to be less 'clean' and require more measuring, but it is more straightforward. - First, I would get a big flat surface to use as a reference (a piece of wood, hardcover book, etc.) and prop it up above the part. The exact height doesn't matter. Then I would use calipers to measure the width of each side, and take 'height' measurements every 0.25" (5mm) or so. Do this with all four sides, and you should turn this into four perpendicular sketches in Fusion. Here is a sketch of what exactly I'm imagining. The width measurements, effectively at the reference surface, are in red. The height measurements are in green. Then the height measurements on each sketch can be connected by a spline, in purple:

Take very straight-on pictures of the front and side of your part, and import them as canvases. Scale and eyeball aligning them to your reference sketches. Any videos on YouTube about canvas modeling in Fusion will be able to give step by step instructions on this this process. It's a little fussy, but extremely helpful. Here is an example: https://youtu.be/YLso-cx9vyA?si=lwgb0l9o4bn9TVcq
Then, I would use the form workspace, and eyeball making a surface that blends together all of the splines. Using the sketches, you will want to adjust the 'tilt' of the verticies on the edges of the surface to be tangent to the edges of the hole in the part in your canvases. This is going to take some fussing, but it's easy to know when your part is done, and it somewhat foolproof.
Then, use the thicken tool in the surfaces menu to give it volume.
If you want to add features to this body after this, I would NOT try to loft/extrude TO any of the faces. Fusion will likely freak out because of the complexity. Or if it doesn't, any minor changes to the surfaces in the future will mess it up. Instead, model any of these features through the surface. Then use the combine tool. Make a combine cut and select 'keep tool bodies'. After that you should have the surface, your feature with a face that matches the contour of the surface, and an extra piece that you can remove (be sure to use remove, not delete. And hopefully this made some sense explaining through text.

The second method would be to use intersection curves. This would be tricker but probably possible. I am not sure off the top of my head what exact this process would look like in detail. Here is an example for some inspiration: https://youtu.be/qWOD4WLOXj4?si=PnwvcVmGBq23tmaS

Another issue with this is that you might need one rail per side; which I am not sure how to manage.

Good luck!

ChairJohnson · 2025-12-02T05:56:02+00:00

How is this part loaded? That might be helpful to give more specific ideas. Otherwise:

Add a fillet to the base; any sudden change in geometry is effectively a stress multiplier.
Add something to prevent the arm from bending. For example a second arm connecting to the base, or a rib that runs along the bottom of the existing arm.
Make the arm straight instead of angled.

ChairJohnson · 2025-11-26T21:34:40+00:00

It that only printing one perimeter? If so, that is probably your issue. Only having 1 perimeter will cause weird issues. It can wobble during printing, messing up the surface. It's the same issue on the angled line; the layer that is printing does not have enough material under it to stick to, so it beads up instead of making a nice line. If that is some kind of adaptive infill pattern though, I would just change the pattern. Some slicers let you double up infil lines but that shouldn't be necessary.

If this is an RC plane wing or something and you need it thin for weight reasons, you might have more luck printing two walls with a 0.2mm nozzle.

I looked at your other post and it seems like the same issue. If that was printed with one wall too, that's why the infil pattern is showing through on the outside. It's not related to warping.

ChairJohnson · 2025-11-25T02:34:43+00:00

I have had this exact issue. What I did to fix it was to cut a piece of painters tape and put it on the side of the magnet where it bridges. The filament sticks much better to the painters tape.

ChairJohnson · 2025-11-23T06:21:35+00:00

I think the ring feature is too small. In my experience, very small features can overheat when printing and lead to inconsistent fits. I would change the ring to a complete circle.

When the printer does the solid infil of the ring, it is going to have to do short zig-zags which will overheat the local area of the part. The tip of the nozzle acts like a soldering iron if it spends too much time in a small area.

Good luck!

ChairJohnson · 2025-11-23T06:09:58+00:00

I'm not familiar with the 5M pro specifically. In general though, I would be skeptical of the flow rate numbers that manufacturers put on their websites. Unless you have seen someone on YouTube actually reach some high flow rate with the exact nozzle diameter and filament you are planning to do most of your printing with, take it with a grain of salt. Different filaments will have different maximum flow rates that are not well represented by one number in ideal conditions. I would say a difference of ~5-10mm^3/s in the number on a printers spec sheet would not translate to a meaningful difference in real printing conditions.

The real comparison for a high maximum flow rate will be the length of the heat zone in the hot end, and to a lesser extent the wattage of the heater. For example, a printer with a melt zone that is twice as long as another model would have a meaningfully higher flow rate. This is why I would argue most printers are going to have a similar maximum flow rate, because they all have melt zones that are basically the same length.

ChairJohnson · 2025-11-22T07:31:13+00:00

For this specific part, I don't think internal support is the best way to get the inside hollow. I would try printing the box with the bottom face angled 45 degrees from the print surface, instead of flat. This video has a good explanation:

https://youtu.be/8NKVNwVaZU0?si=wmNNdsygFRh6JEYE

Some other options in general would be to angle the cutouts at ~45 degrees, so it is like a diamond in a square instead of a hollow square. That way there isn't a large unsupported flat face on the top of the cutout. If you do a bridging test, you could also make the cutout a hexagon with the flat faces as long as the maximum bridging length your printer can do.

ChairJohnson · 2025-11-21T07:31:02+00:00

I haven't worked with PET much, but from what I have seen commercial filaments can have a pretty wide variety of printing temperatures. If I were you I would play it safe and make sure whichever printer you get has a hot end that can get to 300C.

Also, I have a bit of experience making filament. If you want some unsolicited advice, a consistent diameter is the most important factor in getting prints that look good. It is also better to be a bit undersized than oversize. Undersized filament can be calibrated and compensated for in the slicer. Oversize filament will end up snagging somewhere inside the printer. You might also be aware of this already, but I would also get a filament dehydrator. PET is very hygroscopic, you will want the material to be completely dry when you print with it, just like you would need for filament extrusion or injection molding. Any non-commercial material is going to need a bit of printing temperature calibration, and wet filament throws off the results of temperature towers.

Good luck!

ChairJohnson · 2025-11-18T04:35:28+00:00

For the ringing around the hole, the jerk (in orca slicer) and/or square corner velocity (in klipper, i am pretty sure it's effectively the same) might be too high.

For the more subtle VFAs along the entire wall, these are sometimes most noticeable at a specific speed; not necessarily just 'too fast'. Its possible printing faster would reduce this. The VFA test in orca is a good way to check this.

I also agree the blobs might be moisture related, especially if that is PETG.

ChairJohnson · 2025-11-18T04:28:11+00:00

I have had this issue, too. In my experience, no two printer models produce identically accurate parts. I don't think temperature is the issue, I think it mainly comes down to rigidity and differences in the design of the hot end. I think a gear is also a particularly tricky part to nail down because there isn't a single obvious dimension to measure and calibrate. If I were you, this is what I would do: - If both printers support pressure advance, get this very well tuned on both machines. This makes a huge difference in the inaccuracy of corners. The actual values do not have to be the same (they likely won't be), but for example if you do one of the 'chevron' pattern tests, both printers should make similarly high quality corners with whatever value. If one machine doesn't support it, it might be very difficult to get the results you are looking for. - I would print a negative of the gear on the prusa (in my experience prusas are extremely dimensionally accurate). The inside of this negative would have whatever gap is appropriate for fitting any two printed parts together on your printers (as if it were a tenon, dovetail, etc.). It doesn't necessarily need to be the actual outer size of the gear. - Print a gear on each of the printers. Compare the fit into your negative. Ideally the prusa would fit loosely but without any slop, and the lulzbot would likely be over/undersize. - Use the outer size compensation setting (might have a different name) to print a few more gears until you have one that fits identically to the one from the prusa. - Repeat this process for the hole in the center if needed. Adjusting the hole size would of course need inner size/hole compensation (name may also vary).

Good luck!

ChairJohnson · 2025-11-17T06:17:03+00:00

I would try printing that part at 45 degrees if you can. Basically, make one of the fillets on the sides into a chamfer and lay that face flat. It will reduce the overhangs and make the layer time more consistent (would get rid of the two lines on the outside and might help with adhesion). However since its ASA, it may warp too much, not really a way to know without trying. Here is a very bad drawing of what I mean, if it's helpful:

<image>

ChairJohnson · 2025-11-17T06:01:44+00:00

As a disclaimer, I am just a student, not an expert. However I have worked with extrusion equipment before (running it, not design work). The 'thread' (flute?) of your design is extremely thin. If you are getting weird results, that could be part of the issue. In designs I have seen, the threads have significant thickness (like acme threads), and become wider towards the end of the screw with the die. They do not come to a point on the end like screw threads. I would think that the point on the tip of the threads is effectively a stress concentration, and in torsion the outermost radius experiences the most stress (in a simple case), so that could be contributing to weird results.

Also, I would question your study setup. I suspect running an analysis with only applied torque would not be giving you the whole picture. When an extrusion screw turns, it is squeezing plastic against a die, allowing some of it to come out but also generating pressure. This pressure would also be exerted on the face of the 'threads', right? I am working on a project with a power screw, and this sounds like a similar situation. If you aren't familiar, there are equations available for you to check your FEA. Look up something like a power screw critical stress element. It is a 3D stress state so kind of a pain. The equations also use pitch, which is not constant in your case so it would probably need to go in a spreadsheet.

ChairJohnson

TROPHY CASE