Problem- Question about BOSS 5/6 identification and PC Cards

[vonslatt]

I recently purchased a Series II mill and I'm having some difficulty getting it running. The card cage is labeled LSI, ZDI, NTP, ZCK, ERS which from my research indicates it's a BOSS6. However, I found that the card in the ZCK slot is label RCK. Can an RCK be substituted for a ZCK or is this an indication that someone who didn't know what they were doing tried a bunch of card substitutions?

The seller told me that the x-axis had been having difficultly and that one of the driver transistors was probably bad, but I can't get the machine to do anything at all. I have gone through the basic troubleshooting flow chart in the maintenance manual and checked oil level, limit switches, CR3&5, etc.

Thanks?

[machintek]

They are not interchangeable.
A blown transistor is very common and is one of the easier fixes on this machine. Typically they short. Bridgeport specified a Motorola 2N6547.

George

[vonslatt]

Thanks George!

The seller has a 'big box of spares' he's going to lend me, hopefully I will be able to identify the right cards.

Question: The ERS card that is in this machine now came from said box. Is there and easy way to determine if it's from a BOSS 5 or a BOSS 6?

Cheers!

Jake.

[tpmx57]

I purchased a series II boss 6 a few years back.
When I purchased it the sellers said it ran but had a couple issues
I brought it home and when i got power to it I couldn,t get it to run at all.
Everything seemed ok but just couldn,t pinpoint the problem.
I went through all the wiring and fuses everything seemed fine.
One day I took the front panel off the operators pendant and found one of the plugs had come apart from the trip home
I hooked it up and its been fine eversince.
Just an idea for you to check.
I also a complete set of boards and other items for a boss6 control if you need something let me know

[machintek]

The BOSS software resides on a PROM on the ERS board. There are many versions. Some with RS232, some with metric.
Give me the part number of your board and I can tell you what it is.
It may start with a A0.

George

[fredhh47]

I have been using ECG 53 transistors for years. They cost about $9-10 each and hold up well due to a higher amperage rating. I understand that ECG is now part of Philips and they may be hard to get, but worth looking for. I keep a rebuilt module handy (you can get bare modules cheap on E-bay or ask around on this forum), and if I have an axis problem, I just put in a replacement module and worry about rebuilding it later. You can either replace all 4 transistors on the module, or just the bad one. Conventional wisdom suggests the former, frugality suggests the latter, but the reality is somewhere in between. A module with one bad transistor can have one or more weak transistors that are ready to blow a soon as a heavy load is put on them. It is a toss up. Having a spare, I usually just replace the bad one.
SOME of the Boss5-Boss6 boards are interchangeable, but not all.
I have also found that the fuse holders are often a cause for errors. The heat causes them to deteriorate and vibration causes them to loosen, causing arcing. An arcing fuse will work intermittently, while also destroying the fuseholder. Look for dark discolorations on the fuse holders (scorch marks) or even burned out areas. Replace any that look suspicious and always keep them tight. You can buy them from Digi-Key. This is especially important for the fuses for the axes, which are fuses 15, 16, and 17 (X,Y,Z respectively) in the back cabinet, lower left hand corner. Fuse 22 is the one on the exteme left, followed by 15, 16, and 17. Also, Fuses 12, 13, and 14 in the side cabinet should be checked if you have an axis problem as they are involved as well.
Improper lubrication can cause excessive friction and wear, which causes a high load on the axis steppers, especially the X and Y. It may be necessary to pull off the x-axis table and disconnect the lube lines and purge them to clear out old semi-solidified oil, then re-connect them and make sure the machine lubricator pump is able to push oil thru them to the ways. In his series of articles in HSM about retrofitting a Bridgeport CNC with new controller and servos or new steppers (Which should be required reading for a DIY retrofitter) Roland Friestad suggests removing the motor from the automatic oiler pump and returning it to manual operation, especially if the existing motor is bad or shaky. His reasoning is that since the oiler pump runs anytime the motor switch is NOT in the off position, including overnight when you forget to turn it off, as I have been doing for the last 25 years, it wastes lube oil. Streams of oil running down the front and back of the axis slides and a veritable puddle of lube oil around your machine is a testament to that claim, but also proof positive that the oiler is working. Better invest in Oil-Dry or cat litter if you keep the auto oiler.
FYI---Excess backlash in the Y-axis can be caused by a loose setscrew on the large cogbelt gear on the back of the Y-axis. You have to move the table all the way forward, remove a couple small screws and slide the access panel forward to get at it. With the power off, manually rotate the gear around until you can see the setscrew. Remove it and check the second setscrew that is under the first. Jiggle the gear back and forth a little while tightening the setscrew as tight as you can, then replace the locking setscrew. This will remove a LOT of Y-axis backlash. I have a 1982-vintage machine with less than .002 of backlash when the gear's setscrew is tight. And it has been used a LOT.
Fred

[vonslatt]

Thanks for the advice! I've come to the conclusion that I have a bad board and that I would be better off starting a conversion project rather than investing in replacement parts for the BOSS controller. I'll seek out the thread you mentioned and I wonder if someone can point me to this 'Hillbilly' board I've seen mentioned. Thanks!

[rogerfries]

I used a Hillbilly board for about a year, then decided to go Gecko's due to the Transistor problems. To get one contact Darek ashburn@icx.net. It's a good board and it worked well got me started cheap! Ultimately I went with a PMDX-125 which accepts two parallel ports for more I/O's and Gecko's for more reliability, but now we're spending some money. If money is tight and you don't mind occasionally soldering in a new transistor, the Hillbilly board is a great option! Even though I've reworked the machine I feel my Hillbilly conversion was not a waste as I was up and running quick easy and cheap until I could learn/plan enough to re do the entire machine (A big time consuming project).

[vonslatt]

Thanks! I exchanged email with him this morning and will order a board as soon as my next paycheck rolls in. I spent some time with the machine's schematics last night and have decided to run with the existing drivers and save my money for a servo based conversion in the future, for now I just want to get up and running and get some experience under my belt.

Thanks again! Jake.

[rogerfries]

Hillbilly is by far the fastest easiest way to get your machine up and running, you'll love it!

As for the Transistor problems, You probably already know this, but if you are using a rotary phase converter, I'm told that it's critical that the Artificial leg goes to L3. Also try not to E-stop the machine while it's doing a rapid move (unless you have to). I'd also buy extra transistor modules (the Aluminum piece that the transistors attach to) if you can find them so you can have one ready to go if you blow one. These transistors only seem to fail while stopping the machine, never during a run something about the voltage spike when the motors stop suddenly. It really does not happen that often, but be ready for it. I know people that bought these machines new back in the 80's and had this same problem then.

[vonslatt]

Thanks! I did know about the rotary phase converter and the 'wild' leg going to L3. My machine came with a bad transistor on the x-axis drive so I was immediately made familiar with changing those out as well! :-)

[vonslatt]

Oh, and if anyone is interested here's my story of getting the machine home and into my garage: http://steampunkworkshop.com/moving-...tional-rigging