Hakko 936 clone modification help needed - Page 1
Forum section: electronics / projects

author: rocmel
author_rank: Newbie
timestamp: May 20, 2019, 03:27:57 am
content: Hi allI have a 936 clone and I want to modify it to take an old Royel CT207 desoldering iron.I don't want to build a controller from scratch.The problem is that the desoldering iron has the heater and sensor internally connected as common.What mods do I need to make to the 936 board, in order to use it.

author: amyk
author_rank: Super Contributor
timestamp: May 20, 2019, 04:44:42 am
content: The 936 and clones run the heater from AC, and rely on the sensor being isolated and being able to drive both halves, so the circuitry won't work with a commoned heater-sensor element.There's also the question of whether the temperature sensor has suitable characteristics for the 936-style controller; either way, the closest I can think of as a solution is to have an amplifier/level translator that simulates a resistance across the 936 sensor inputs.

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 20, 2019, 05:10:43 am
content: I have a few Royel desolder stations and other Royel stations and some 936's. The Royel is common between the heat and sense. The Hakko is not. They also have quite differing sense resistances (at ambient temp).CT14 iron is 23/24ohm, 2~3 ohm heat (have seen 7ohm heat),CT6 iron 23ohm sense 3ohm heat (have seen 8 ohm heat);Ct200-1M desolder iron 24~29Ohm sense and 3~3.5 ohm heat.....The Hakko is 2 ohm heat and 50ohm sense (ambient)I think I have quite a few Royel PCBs on hand. I replaced some with my own made versions I changed the cal pot it was peeving me off. The new PCBs hold cal much better. They are in general still +/-10 degrees C at iron tips. Which is excellent, they were the first Mil Spec soldering systems. They were excellent but the Royel soldering was sold and fell apart. Last I heard were selling cheap systems from Vietnam I purchased one to see, they were really bad. Anyway other mfgrs caught up quickly caught and passed them once Wash had left. When they were part of Varian they were a great company.Anyway I digress....IMHO...either make some new PCBs to run the royel irons you cannot use a Hakko or clone control. I have quite a collection of Royel PCBs tip etc. Despite the Hakko, guess what Solder stations I use all the time? I have a lot of measured data on their irons and PCBs. Before I got my desolder station I was going to my my own desolder using their control PCBs.edit:gotta say definitely some of the values (and schematic ) on the Royel drawing is quite different to what I have and the layout is odd wrt to mine. Ive seen 3 variations of Royel PCBs

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 20, 2019, 06:00:41 am
content: I also meant to say I have PCBs for the earlier Adcola soldering systems. These were the precursors to the Royel. I have a few Adcola irons running on my royel.

author: rocmel
author_rank: Newbie
timestamp: May 20, 2019, 08:50:41 am
content: The Royel CT207 is from the 80's, I've tested it and heats & sucks !!!!Heater is 4 ohmssensor is 24 ohmsThinking of getting a T12 mini, modifying the comparator and the back end with a n SCR /triacthere is also a simple controller that seems to work youtube videoI'm not too fussed with temp control accuracy.

author: dragondude
author_rank: Newbie
timestamp: May 07, 2020, 03:52:31 am
content: wasyoungonce, you wouldn't happen to have a spare Ct200-1M you would like to part compnay with would you?

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 07, 2020, 08:00:18 am
content: Ahhhh you do have me in a tight spot. I have 2 working de-solder (CT200m) irons units and cannot part with them I have 2 other broken units where the nichrome heaters have come away from the common conductor to the terminal on the iron handle core. I have a few Royel irons that appear to have all failed like this......I have unwrapped these iron cores and can see the issue ........they have a small tiny crimp pad I believe they spot weld the nichrome wire to a terminal conductor. If I could re-spot weld or re-terminate them successfully then yes no problems I can give you an iron. But only if I can fix them!.They are constructed with a thick outer earth shield wire connected to GND on the main PCB. This unwraps easily. The next layer is a heat resistant type string material (Keeps heat in), this unwraps easily. The rest is mica insulation formed to fit the metal core and heater/sense coils. Apparently its easy to heat mica to form these shapes (with high heat).The irons have a common terminal (pin 1 on the handle) and this is common pwr (fed with 26VAC) on the iron. This common also connects to a nichrome heater joint (typically 3.5ohms to 7ohm) depends upon iron size/power type. The other side of this heater connects to a heater pin on the iron handle (pin2 heat). The common is also joins to another nichrome terminal for "heater feedback or sense" (around 27 ohms ambient, PTC type...I think) and again the other side is connected to another pin on the iron (pin 3, Sense).So, you can tell where there are any problems by measuring resistance between the common sense and heat pins. The Ground as said is just an outer ESD sheath.So, I have some (3) non working C200M elements "heat" and if I could re-spot weld them they could be made to work again. The insulation between the iron metal tube is mica formed rolled to fit. Apparently this mica is easily heated and formed to the shape. Of course as its heated over and over again but this isn't an issue. Its the nichrome wire joins.If you or anyone has ideas on how to rejoin these dissimilar wire metals then they could be back in use yes you can have one.These iron heads fit into a plastic iron holder and I do have some although a little worn from use. I haven't found a way to re-mould them back into shape or repair cracks or damage. Heat and acetone doesn't work.I have QTY 3 new de-solder (CT200m) handle metal cages and glass tubes and many filters for these and some new and used glass tubes and fittings for these units. Also the spring clip to hold the metal cage to the iron plastic tube outer.So...its a quandary If I could join the damaged nichrome joins then "yes" no problems, but until I can...then sorry...all I can do is help with some general spares. Are you in Melbourne?Brendan

author: dragondude
author_rank: Newbie
timestamp: May 08, 2020, 05:26:40 am
content: WOW. Thanks for the rather informative answer. Actually all I am after is the plastic handle. Mine has perished and has crumbled. Still usable, just, but would like to replace it. It is a foot operated one not one with the button on the handle. it would be much appreciated if you could part with one of these.In Cairns.

author: dragondude
author_rank: Newbie
timestamp: May 08, 2020, 05:45:40 am
content: PS. Do you know what guage the wires are you want joined. You can get some very small splice type crimps. They are uninsulated so don't take up much room.https://www.te.com/global-en/products/terminals-splices/splices.html?tab=pgp-story

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 08, 2020, 07:06:30 am
content: Ok here are some pics of free things I can give you:A used Handle piece. Needs a little repair but is use-able.A new metal handle cage that the above handle fits into. See pic.A used Handle vacc tube line (not in pics) but good condition.Some new glass tube filters. See pic.A new glass collector tube. See pic.Some used tips (but in good condition, 1mm, 0.9mm and .8mm...IDs. See PIC....not all of them!In one accompanying pic I put up, you can see they (Royel) made the 200M iron handle from their other iron plastic handles...... just cut and glued it all. The hand piece dorsal cut is to allow the larger Vacc head and tubes to fit the handle. As for what glue I have no idea. Not Acetone nor heat possibly tarzans grip or some resin might fix it. I've yet to determine what the plastic is to glue it. Anyway the Handle I can give you is quite usable just needs a little attention. These were made in the days Royel was a great company. They were sold after their best engineers left have gone to the dogs now...selling cheap Hakko type knock-off, 3rd time copied, under performing crap from vietnam. Gone are the days they were made in Melbourne.What Royel Vacc station do you have...the one with the "Gast vacc pump"?? Is it for a repair workshop or DIY? ....Not that I care.Anyway get back....you just pay postage they are yours and whatever I can dig up, within reason. I have to many many Royel stations singles, duals de-solder, multi-rework with resistance tweezers and thermal wire strippers ...AIO! Hahaha

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 08, 2020, 07:14:07 am
content: Oh the nichrome wire is joined inside the iron hot end.....way too small to fit "joiners"! I was watching resistance welding of wires like this......can be done but beyond me atmEdit. Actually some of those small flat crimps look very similar to those in the irons to join nichrome and wire...... Very small....around 2mm or less square and 1mm thick.Edit 2 I’m off to hospital tomorrow! ....again ....if you want stuff say so otherwise I could be in for a months or three! I can pack it a and family can send It for me.Brendan

author: dragondude
author_rank: Newbie
timestamp: May 11, 2020, 12:35:11 am
content: Sent you a PM

author: dragondude
author_rank: Newbie
timestamp: May 11, 2020, 12:37:05 am
content: Also might be interested in the resistance tweezers and wire strippers. Could you please post a pic of those?

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: May 11, 2020, 03:36:31 am
content: Many thanks.....my message reply disappeared so here's an abridged.... to cut to the chase:Good to hear from another RAAFie.Thanks for tip on cleaning Vacpump. Its a Vane type "Gast"I uploaded some pics to my google drivehttps://drive.google.com/open?id=14u1E1BrbVzax5sVi19u2dotU3lw2dqR0I can spare one CT200 handle used but ok, a handle cage 2 glass tubes filters, vac flex tube from iron to station, some used but very good iron tips (~6), some new iron tips (~4) around 5 new Pace vac tips that fit the iron and new ferrules to fit the tips. I'll throw in a new thermal wire stripper (American Beauty see pic) I only have one Resistance tweezers set..sorry that stays.I have Quite a few other brand new tips for STd irons large and small types ....around 150+ brand new tips I scored from fleabay. I don't have their part numbers but Hoof's spade, chisel, points, 2mm/3mm/4mm/5mm and bigger...I can spare some of these....all stuff for free you just pay postage.Happy to help fellow RAAFie. I re-made my PCBs for the station with new PCBs and multi-turn post,,,didn't get the LEDs right they OEM were real low current. Some irons like the CT14's have offset temp that I just note with a tag on the iron to compensate when I set temp. My Favourite is an old ADCOLA iron (forerunners for Royel)built like proverbial brick craphouse works so well and is ~70Watts. Its like new 40+ years since new and is the best iron I've ever used.! I'll put up pics when I can. I love my Hakko 936 for drag solder though. I recently did a QFN144....the Hakko nailed it first go. Those drag cup tips are to die for!But.... I'm in hospital atm could be a month or 2 or 3! More spinal fusions...possibly all! Already fused S1-L5 and C4 - T2....so...looking forward to this "like a finger in the eye"! So talk soon when I can.Brendan .