Manual solder paste dispenser - recommendations? - Page 1
Forum section: electronics / general

author: ebastler
author_rank: Super Contributor
timestamp: May 30, 2021, 08:13:17 am
content: I have used conventional soldering irons or stencil/solder paste/hot air for SMD soldering so far. But do occasionally find myself in situations where neither approach works well -- especially during repair and rework, when I need to fit a component in between other components which are already populated.I would like to add a simple, manual solder paste dispenser to my toolkit for this purpose. This has probably been discussed here before, but I could only find references to more complex, motorized units in older threads.The one below looks plausible due to its simple mechanism (no slack, easy syringe exchange, I would hope). Does anyone have experience with it? Or can you recommend a different commercial device? Thanks!https://www.tindie.com/products/avandalen/disper-micro-dot-solder-paste-syringe-dispenser/Edit: Here's another, similar unit. It might be an advantage in this design that the syringe body always stays in the same position, independent of filling height. But it needs a custom syringe (with serrated plunger rod). It seems geared towards dispensing somewhat larger volumes, i.e. strands of paste rather than individual dots? Any reports from first-hand experience are much appreciated!https://eleshop.eu/jbc-dpm-a-manual-paste-dispenser.html

author: wickated
author_rank: Frequent Contributor
timestamp: May 30, 2021, 08:20:13 am
content: solder pastes in tech syringes work good with plunger and as thin as insulin needles.

author: ebastler
author_rank: Super Contributor
timestamp: May 30, 2021, 08:29:02 am
content: Quote from: wickated on May 30, 2021, 08:20:13 amThanks for the reply, but I am not sure I understand your point. Do you mean you just use the bare syringe + tip, and push directly on the plunger with your thumb? In my experience it is difficult to dose reproducibly that way. Also, pushing without any additional leverage becomes quite strenuous, especially when using thin tips with a lot of resistance.Or did you have something else in mind? -- Also, what is a "tech syringe"? Just the one you buy the solder paste in?

author: thinkfat
author_rank: Unknown
timestamp: May 30, 2021, 08:59:54 am
content: Not that I particularly recommend it, but JBC has solder paste dispenser similarl to the one shown in your picture. I've been using it for a while and it is way more precise than just squeezing out the paste with your thumb. The main drawback is that the typical paste syringes don't fit. They sell their own (empty) syringes and you have to fill them with paste by yourselves. That's a bit inconvenient.

author: ebastler
author_rank: Super Contributor
timestamp: May 30, 2021, 09:04:38 am
content: Thanks, thinkfat! I was editing my original post to add a link to the JBC unit while you were posting.How well does the JBC dispenser work for dispensing small dots of paste -- say for individual 0402 pads?

author: thinkfat
author_rank: Unknown
timestamp: May 30, 2021, 01:52:48 pm
content: Well, it's still a manual tool and a lot of the precision is still "in your hands". It's just easier to dose the force. From experience, 0603 isn't a problem, 0402 is outside of my realm. It also depends a lot on the paste itself. Wet paste seems to be easier to work with than dry paste.The problem is mostly having the paste sticking to the pad and then "break off" when you lift the syringe instead of pulling off the pad. That challenge will remain the same. What has always helped me here is to heat up the board to maybe 50°C or so, with a bottom heater or just hot air. This usually allows the paste to just wet the pad and stick.

author: wickated
author_rank: Frequent Contributor
timestamp: May 30, 2021, 03:04:01 pm
content: Quote from: ebastler on May 30, 2021, 08:29:02 amlol no. no thumbs were hurt.yep, syringe not applicable for reuse with liquidsp.s. also u can make some DIYand some cyberdyne technologies

author: ebastler
author_rank: Super Contributor
timestamp: May 30, 2021, 03:22:49 pm
content: Quote from: wickated on May 30, 2021, 03:04:01 pmI still don't get your point, I'm afraid. That syringe in the photoisjust the syringe one buys the solder paste in -- "Mechanic" brand solder paste in this case. And the guydoespush the plunger directly with his thumb. Besides, it is obviously a staged photo, with ridiculous white gloves and the soldering iron directly on the paste (without the luxury of adding an actual part to be soldered).So what is your actual recommendation? Do you have first-hand experience with solder paste dispensing?

author: wickated
author_rank: Frequent Contributor
timestamp: May 30, 2021, 04:13:18 pm
content: Quote from: ebastler on May 30, 2021, 03:22:49 pmwith both flux and solder pastes yes. there is no total difference in manual or robotic dispensing exept of repeatability, for big surfaces you anyway should use template.with metal plunger you dont get solder leaks from nozzle after you put it offjust did some taps, i think its just a matter of skill. you know there is always a korean that do it better.

author: I_Saldana
author_rank: Contributor
timestamp: May 31, 2021, 06:08:56 am
content: I am frankly more interested in a needle cap.A needle is fine for when you have to do a few pcb's, but when you have some repair work to do there is more paste gone from cleanup and stuck in the needle than one actually used.As for this.. humm... thinking about ready made off the shelf solutions..have you looked into this?google image this:dentist composite dispensing gun

author: I_Saldana
author_rank: Contributor
timestamp: June 01, 2021, 09:15:10 pm
content: Just bought this as a novelty. I expect it to be shite.Maybe it will extend the shelf life of aging paste where trying to squeeze it through manually no longer works.https://www.aliexpress.com/item/1005002527239455.html

author: ebastler
author_rank: Super Contributor
timestamp: June 02, 2021, 04:39:38 am
content: Quote from: I_Saldana on June 01, 2021, 09:15:10 pmIt looks well-made. How is it meant to be used? Is the idea to hold it in your fist, with the thumb slowly turning the thumbscrew all the time to dose the paste? Or to use your other hand to operate the screw?

author: I_Saldana
author_rank: Contributor
timestamp: June 02, 2021, 09:10:22 am
content: Quote from: ebastler on June 02, 2021, 04:39:38 amI have been thinking about exactly that throughout the evening yesterday. I will keep you informed on how(literally) it performs when I get it. fist with slow thumb movement seems a viable option yes.. But to anyone who caulks it should be obvious this thing will keep at it until you turn the wheel the other side. I am hoping for at the very least some chuckles for my 8 €.Edit:Maybe tightening it completely gives the option to squeeze the actual syringe enough for a mm or 2 of paste to come out very precisely. Then tightening it again.. *shrug*

author: oz1sqt
author_rank: Contributor
timestamp: June 22, 2021, 08:55:40 am
content: I just bought the one from JBC you showed as example, i thought it was a bit expensive, but now I'm in love.https://eleshop.eu/jbc-dpm-b-manual-paste-dispenser.htmlIt, is easy to dose without much pressure, and you can adjust further via changing size on the needle/tip - And it seems more simple, than many other more or less DIY solutions.

author: ebastler
author_rank: Super Contributor
timestamp: June 22, 2021, 10:02:38 am
content: I have bought the 3D printed dispenser from Albert van Dalen (first picture in my OP) in the meantime. It was shipped very quickly from the Netherlands. Dosing the solder paste works well and the unit is a handy size, with a short hand-to-tip distance.But clamping the filled syringe into the white holder is quite awkward: There is no good way to pull back and hold the spring while one tries to clip in the syringe. The brass thread insert for the adjustment screw protrudes a bit on the inside of the white bracket, and gets in the way when one tries to slide the spring-loaded plunger into its position. And the spring seems stiffer than necessary. -- I'll experiment with a weaker spring, and an additional spring retainer/washer to get a better hold on the spring while clipping in the syringe.

author: I_Saldana
author_rank: Contributor
timestamp: June 25, 2021, 03:02:47 pm
content: Today the thing arrived.As soon as I have a QFN to solder I'm taking pictures.It is heavy though.. but that was to be expected.

author: SteveyG
author_rank: Unknown
timestamp: July 07, 2021, 11:24:48 pm
content: The JBC DPM-B is definitely worth considering. I normally use a Metcal DX dispenser, but sometimes you want the manual control.It's a shame it doesn't accept larger syringes directly, but it's simple enough to decant some into one of the provided syringes.

author: helius
author_rank: Super Contributor
timestamp: July 08, 2021, 04:35:14 am
content: You can browse the catalogs of industry tool suppliers, they have several types of manual applicators for solder paste.Here are some examples:

author: ebastler
author_rank: Super Contributor
timestamp: July 08, 2021, 05:25:22 am
content: Thanks @helius, that is quite a selection indeed. Have you used this style of dispenser to dispense small individual dabs of paste to SMD pads? They all look like they were designed for dispensing larger volumes?(At least for me, a pistol grip offers less positioning accuracy than the pen-type design. And the "trigger" levers also seem designed to move the syringe's plunger by macroscopic distances each time you press them. I assume these are made to e.g. dispense solder paste onto a stencil or such, rather than the direct "one droplet per pad" dispensing I am after.)@SteveyG -- thank you for the vote for the JBC. I might shell out some money for that one, since the 3D-printed dispenser which I got remains rather fiddly to set up.

author: DavidAlfa
author_rank: Super Contributor
timestamp: July 08, 2021, 08:33:21 am
content: Last week I thought about this when my solder paste dried and was hard as hell to squeeze out!This seems a nice motor. Encoder output, fine thread, high reduction ratio and fits inside the syringe!https://www.aliexpress.com/item/1005001785275240.htmlI don't think I'll use a 18650 heavy monster there. Maybe something small like 10180 or 14250.I was making some calcs. Given the 16mm plunger (201mm²), the motor has 0.35mm thread, 240 reduction ratio.For each complete rpm, the syringe would pull out 0.35*201 = 70mm³ of paste.The average 0805 pad size is 1.3*0.7m= ~1mm². Let's say you put 0.5mm height of paste, it would be ~0.5mm³ of paste.0.5/70=0.07rpm required.With 240 reduction = 1.71 motor turns.I don't know the resolution of the encoder, but it seems it will require a really fine control. Plus retraction to avoid spilling.

author: LordXaos
author_rank: Contributor
timestamp: July 27, 2021, 11:30:04 am
content: After reading this thread I dared fetch me the JBC DPM dispenser, and after giving it a quick first try I am not at all disappointed. The amount of paste dispensed can be very well controlled, and it can be aimed very precisely.It might not be the cheapest choice, but then those pre-filled single-use syringes are not exactly cheap either, and getting a proper dose out of those directly I found virtually impossible.

author: ygoe
author_rank: Newbie
timestamp: August 08, 2021, 10:08:32 am
content: Hello,I came to this place because I also found the JBC DPM dispenser and were looking for some reviews of it. This sounds good and I'll probably get one of them, too.Now there are two models as far as I can see:DPM-AandDPM-B. I'm not sure what the difference between them is. Can the DPM-B hold larger syringes? I'd see if I can get one of the Chip Quik TS391LT, which should have a good alloy, low melting temperature, and slightly different model numbers have received good reviews. It also says it has a long storage period when used. The syringe contains 15 g and it also says "5 cc". Google says that means "5 ml". Could I put that directly into the DPM-B (or -A) or will I have to fill some of it into a syringe provided with the JBC tool?If somebody has a better recommendation for a solder paste, please let me know. It has to be lead-free.I already did some SMD hand-soldering on self-designed PCBs (down to 0805 and 1.27 mm pitch) but have no experience with solder paste and reflow soldering yet. I figured I need to move on to that process to handle certain components I need for my hobby projects.

author: Psi
author_rank: Super Contributor
timestamp: August 08, 2021, 10:21:28 am
content: Quote from: ebastler on May 30, 2021, 08:29:02 amThat's what most people do.Note, if you are having issues requiring too much force, then your dispensing needle is probably to small or you are using solder paste with a large ball size. A smaller syringe is also an option.As others have posted there are automatic and motorized options but unless you are planning on doing this all day its probably not worth it.I suspect those manual hand-tools that hold a syringe will be hard to position due to the hand grip being to far away from the dispensing end. but the one in your first pic looks like it would be fine.

author: SteveyG
author_rank: Unknown
timestamp: August 08, 2021, 12:51:03 pm
content: Quote from: ygoe on August 08, 2021, 10:08:32 amDPM-B is the newer version and accepts two different syringe sizes.

author: sleemanj
author_rank: Super Contributor
timestamp: December 02, 2021, 10:48:19 pm
content: I took some inspiration from the Tindie one linked in the first post, and another one which also was inspired by it, and created an easily 3d printable version that simply uses an elastic band for the retraction tension.The lever gives about 10mm of plunger travel, about 0.2cc, as with the other designs it has multiple steps if you want to refil less often, just move it backwards a couple notches when the lever runs out of travel.Waiting on some fresh solderpaste so havn't actually tried dispensing with it yet, but as long as the elastic can give enough pull to retract, I don't see why it wouldn't work, the lever can exert plenty of force.If you have a 3d printer it should take you an hour or two to print and a couple of M3 screws at least 30mm long.https://www.thingiverse.com/thing:5153474Obviously you'd want to use a dispensing tip on it

author: helius
author_rank: Super Contributor
timestamp: December 03, 2021, 12:39:16 am
content: Quote from: ebastler on July 08, 2021, 05:25:22 amThe only one I have used is #7, the EFD Specialty Products DispensGun.It is capable of small dot sizes—the key is that the plunger moves both forwards and back on a pivot, it isn't only pushing forwards like a caulk gun. So when you release the trigger it re-sets and stops the paste from drooling. I don't know how the other types operate.It also comes in models for 3cc, 5cc, 10cc, and 30cc/50cc.

author: Carioca10
author_rank: Unknown
timestamp: January 19, 2022, 11:45:13 am
content: I have bought JBC DPM-B in Kardilab in Slovenia for 48€ with “Posta Slovenia” with tracking number for 10€ shipping costs to Brazil.https://kardilab.com/shop/consumables/jbc/jbc-dpm-manual-solder-paste-dispenser/I bought it because even though the material is perhaps 3D printed, it must be of better quality.As always it depends on each one.Most of those for sale have freight to Brazil from international private carriers, some charged more than 150€ for shipping.Concerning Kardilab, they state they have also a really good responses regarding fluxes and soldering pastes. They also have a repair shop and they use all of their products. This was the reason their online store started, so that they want share all the good tools with others.I will try their soldering fluxes and soldering pastes next time.I hope this information is also useful for someone else.

author: sleemanj
author_rank: Super Contributor
timestamp: May 26, 2022, 03:13:07 am
content: FWIW, I finally got off my fat ass and tested my dispenser design (last post on page 1), it works great.A 20G (Pink/0.6mm) tip works best, and of the (aliexpress) pastes I've tried so far surprisingly the cheap-ass looking onehttps://www.aliexpress.com/item/4000602425410.htmlworked best, dispenses easily, produces good looking joints, and very very minimal visible flux residue, just the faintest hint. I reflow in my, very literal, toaster, no particular profile, heat to ~200' and switch off.

author: Psi
author_rank: Super Contributor
timestamp: May 26, 2022, 12:44:34 pm
content: Quote from: sleemanj on May 26, 2022, 03:13:07 amYou should really go a bit over 200C. The flux may not fully activate otherwise.I usually like to see the temp probe hit 210-220C

author: sleemanj
author_rank: Super Contributor
timestamp: May 26, 2022, 01:27:46 pm
content: Yeah it overshoots by about 10 after turning off, it's just a triac controller set down real low so not exactly precisely controlled.