Basic 2DOF Configuration and FAQ

Thanos, many thanks..I will work on that..Apply flux on the tracks and then apply the solder over it..
Do you know the file to upload at PCB Express?
I tried to build my own lcd board with the laser print method, it looked ok but I didnt test...I dont want to waste more time building a new H-bridge on my own and it doesnot work, so I was thinking about PCB express for a backup board in case my fixing wont work...
let me know
tks
Caue

@ cauehawaii

Re: ExpressPCB layout of the DSMhb, look at the first post by Thanos as it explains the mods I made to the h-bridge, and choice of 2 files ready to submit to ExpressPCB service here:

tronic-s-amc-motor-motion-controller-with-pwm-servo-output-t559-420.html#p9129

R-eng

Your fixing will work if you do it like we said. Remove the MOSFETs from the connectors during soldering to avoid overheating them. To get the wires hot enough you have to stay a longer time with your soldering iron ... a bit risky for your MOSFETs if you are inexperienced in soldering :thbup:

Step by step instructions for beginners:
- remove MOSFETs
- remove burned wires
- clean burned areas of the PCBs and the solder joints using a toothbrush and isopropyl (burned copper and tin is really hard to solder). In case of need aftershave will do the job as well
- bend and cut the wires (use pictures or your other PCB to see where the thick tracks have been)
- add flux to the solder joints and the points of the wires where they will be soldered
- have a beer (flux has to dry)
- tin the wires (points of the wires where they will be soldered). Use small pliers to hold the wires ... they will get really hot. On thick wires you have to stay a longer time with your soldering iron to get the temperatur high enough for a propper solder joint
- position the wires to your PCB and solder only the first/last solder joint.
- if neccessary bend the wire to match all other solder joints
- heaten the wire at the next solder joint. If it's hot enough, put it down to the solder joint with a screwdriver and add some tin-solder. Remove the soldering iron and hold with the screwdriver a few seconds
- after the last solder joint it is a good idea to solder the first again. In the first step you may have moved it a little bit during cooling down which may cause a bad solder joint ... so do it again
- reassemble the H-Bridge (MOSFETs)
- have a beer and celebrate your working H-Bridges
- optional: fix the wires with superglue between the solder joints

Sounds a lot but this job is done in a few minutes - except for drinking beer and celebrating

Even if you order a new PCB you have to strengthen all of the thick tracks with wires.

This alternative works just as well with less hassle...but do it after placing all components using those traces.

R-eng

Yes R-eng, you are right, I would do so. But I think it's no option for one who is just learning to solder
And with the masked PCBs it will never work to tin the tracks.

I should have been more clear. It would be the better option if, and when, he decides to do up new boards using ExpressPCB (which are not masked). IMHO it would not be too difficult to do with just a little practice. But maybe it is a little ambitious for now.

R-eng

R-eng, thanks for that, I knew I saw somewhere but I could not find yesterday..

Krumel, Thanks A LOT for the detailed explanation.. that was great...I think I will proceed with both ideas.. actually 3 ideas to proceed..
I may order one board from PCB express so I can reinforce the tracks myself later and learn how to do that... I will also fix the bad tracks as Krumel said so I will also learn that...and I may build my own h-bridge with the lazer tone method and I will improve my skills with that as well... - a little ambitious right

After I fix the bad tracks with the copper iron, I will have to reinforce the remaining tracks, correct?
As it has mask over all the tracks, if I apply fux on top of the masked tracks, will the reinforcement work?

I build a lcd board myself last weekend to see what happened, and the result is attached (one track I skratched just to check the resistence), but I tought the tracks were too dark in comparison with some results on online tutorials...just give me a quick tough on this if possible...

Well I am going to the store now to buy Flux, connectors and a couple of extra Mosfets just in case... ahh Krumel, I will buy 1 case of beer either to celebrate my repair, or to forget my disaster :

You don't need to solder the wires all over the tracks. Just solder them to the solder joints (at the MOSFETs and the connectors) will be ok. Have a look at Thanos' example some posts before.

No, the mask is a paint which can't be soldered. If you want to solder s.th. on it, you have to scatch the color off. In your case that's not neccessary. Just connect the wires to the solder joints will work fine.

Thanks..I think I got it... hopefully my wife gives me some free time to work the weekend on this...

I will connect the wires to the solder joints passing over all the large tracks.....because I wont be able to add reinforced solder on top of the masked tracks I will use the wire instead...but soldering only on the solder joints

thanks again and sorry for the questions...I have been so interest to learn new things with you guys that I am afraid to get distracted from my main goal..which is get my x-sim up and running ...but I am really learning a lot :

thanks
Caue

guys I had to get back to work to make some $$ and I have had not much time to work on the boards this past week, hopefully next week I will have a couple of days off...

I will keep you guys posted when I get back to the boards to fix the burned tracks

thankks
Caue

back here to the forum again, sorry for taking so long but I had to work had no free time in the past 2 weeks and I won´t have much more free time in the next 2 weeks... I had time to pass the wire over the burned track and reinforce the tracks with solder... when I tested the leds blinked ok, but the motor did not move...perhaps problems with the mosfets??
Also, I did not have much time for testing as the reinforced tracks started to smell and I turned off just before the reinforced soder was totally buned in one of the tracks...

so I am about to order a new h-bridge without mask, they build 3 at minimum for 80US$... I think it will be faster than fixing this one...
then I remove the components from the burned one and insert on the new board...reinforce the lines with solder and try again... that will be my last try..if I cant move on, perhps I just put this project on hold until I cease my frustrations

PS. I DIY some new pedals with new potentiometers and attached to the cockpit, it is working with my momo wheel...the old pedals were crap..I will post some pictures later on

Regards
Caue

@ Caue

Do not reuse the old parts. You obviously are shorting out some where, so if the part(s) were not damaged, some part(s) sure are now! That is why you have a funny smell. The traces do not burn for no reason.

Buy all new parts or else you'll be right back in the same boat of frustration. You obviously do not have the experience or equipment to test out used parts. Save yourself the headaches and lost time.

Start with a new pcb, etched professionally, no solder mask. Put all the parts in according to Thanos' online instruction, watch out for static, especially with the MOSFET. First, test the wiper motors connected directly to a battery to confirm they are good. Connect up everything again and run the motors with no load attached (ie. out of a simulator). The DSMhb should be able to run just fine (heatsinks a must) without building up the pcb traces at first.

Once you have confirmed that everything works as it should, then add solder and/or additional wire to the traces. Retest with no loads again before moving on to using it on the simulator.

If you don't want to take the time to do this procedure correctly, then ask if anyone in the community will build you a complete device, and expect to pay then for time, material, and shipping.

R-eng

thanks for the post man... I believe it is a good idea to use new componentes... that will be some more $$ but it is better to do that than to have a massive headache looking for bad components...

I do have the resources and the energy, but I figured out that I don´t have that much free time to learn 'everything' about electronics yet.
I already ordered a pcb , no solder mask, then I will place new components on it and reinforce the tracks, heatsink is already set, I will send some pictures when it arrives, it should be around next tuesday/wednesday

If it does not work, I will have to ask someone to build one for me and spend some more $$.. I can´t just give up on my simulator and continue using only my momo wheel.. to be honest, I havent´played anymore since I started building my sim, it is just no fun anymore without movements

regards
Caue

Hello Caue,

for your problem with LCD :
when i connect my LCD the first time, i couldn't see anything on the screen ... I thinked the LCD wasn't good, but in fact, it was a contrast problem. So I tested with a resistance between the contrast adjustement and the PCB, and now it's work.
For test, you can make a stripe with a cutter and sketch with a carbon pencil at this contact :



For my LCD (WH1602B with blue screen) i need to use a 6k.

Regards,

T4zt00n