cyclotron's Dyna2000 retrofit

[cyclotron]

Hi all,

I just scooped up a rather beaten up 1987 Dyna2000 and I'll be transferring the electronics and motors from my old homemade "router" over to the dyna. Right now i'm in the middle of taking this thing apart and cleaning it. For sure, it needs it.

The original motors and driver boards (which I assume were not in the rear cabinet but rather riding tandem on each axis next to the motor) are all gone. The nice looking Nimec Lambda power supplies are intact and appear to be working... There are also two other boards and I'm not sure what they do but if anyone wants them I'd be happy to work something out.

The main features, or lack there of, compared to the higher number models appear to be:

Separate oiling ports for each dovetail of each axis

A strange plastic (acetal?) with a spring loaded anti backlash mechanism

The ways are nothing special and have scraped (sort of) tapered gibs. The ways are also frosted for oil retention.

I'm sad that I didn't find a machine in better shape or with nicer parts, but this machine will be a huge step up for me in terms of vibration control, stiffness, and durability. The table is in really good shape and spindle sounds good across its range of rpms.

Questions:

Is there a service manual floating around online? I'm particularly interested in the electrical drawings.

Is there a way to oil the spindle bearings?

Has anyone successfully kept the spindle motor electrically system and integrated it into a conventional mach3/breakoutboard/gecko type system?

Whats the deal with these anti backlash nuts? are they reliable? from other discussions I've seen, it is not cheap to order parts from Dyna. Upgrading to a "Super-nut" would probably cost a lot... it might just be easier and cheaper to grab some ball screws off of ebay. Thoughts?

I'll be uploading photos when I can but I don't have access to lots of internet right now.

[Fastest1]

First off, Congratulations on the acquisition. The drivers should have been in the rear box if it is anything like my 2400. The steppers were mounted with a small board at each axis. This board was to combine the limit switch wiring and stepper wiring into 1 harness. The lamda power supplies are good but only 24V and 5V in mine. The 5v is used for the spindle control board. My 2400 has a Bijur auto oiler on all 3 axis. I have run mine with a G540 and the original steppers quite successfully but would prefer a direct drive. I am in no rush to change it though as the machines travels are too small to put much more effort into, IMO. If the leadscrews and nuts are similar to mine, they are of high quality. My backlash measurements were always .001 or less and generally less than .0003 if my memory serves me right. The quality of machining is top notch and all aspects of the machine are top rate especially considering it is a 1980's or earlier design. I believe there were 2 builds I can think of with that machine here on the zone. Why do you say the ways are nothing special? That frosting is hand scraped. Regarding the interface of the spindle with Mach, I run my spindle manually at the moment but could see 2 ways of solving that issue. First just use a relay thru the G540 or BB board and have it control the on/off of the spindle. Second would be to possibly switch it direct by connecting or disconnecting the ground to the spindle control board. The original set up was like this with a switch that let you select between manual or auto control. I personally have not tried to switch it thru my G540 until I can verify the grounds from the machine and or computer side are not linked. Electronic parts are rare on this machine. A retrofit would be possible if I fried it but no rush just yet.

[Fastest1]

You have seen this 1 havent you?More of Dave Fahringers Projects
Or Alex Coles here on the zone?

[cyclotron]

Fastest1

Thanks! i got this thing for 500 bucks and i already know that even just the learning value from fixing it up will be worth it... that said the few that i've seen documented online always look pretty mint! and mine doesn't

In regards to the ways and gibs, I'm no tool maker, but from what I have read, frosting on ground ways only facilitates oil retention in the ways and should be more or less standard. Scraping on the other hand attempts to approximate very flat surfaces, or in this case, perfectly mating surfaces. The main machine tool reconditioning text that I have says that very high quality surfaces are scraped to ~30 bearing spots per square inch (if I remember correctly) the gib isn't even reaching 10 spots/square inch. I'm guess the scraping on the gibs is just there to help with the final fitting of the dovetails, but that bearing quality is left up to the grinding. But hey what do I know?

That said... I should be more humble, Its just that I've been spoiled by the machines I've worked on thus far, and the quality of parts produced has just as much to do with the operator as it does with the idiosyncracies of the machine tool!

I'll have to get back to my work space to check the power supplies but I was hoping, not only to control on/off of the spindle, but also spindle rpm's. I already have an encoder, though I'm not sure its needed. I won't mess with the current wiring though, not until I get a schematic. Until then it will have to be manual.

what would be cool, is to preserve the original Manual/program spindle switch, and retain the manual functionality, while adding rpm control to the program section... I guess with a separate board? Could you program RPM changes in your machine's original configuration? OR were the Dyna machines always meant to be semi manual with a program on/off only?

I'll try to get some pics up of these lead nuts, but just to clarify, they are not adjustable and they use two nuts that are splined together and pushed apart by a fat spring to take up any slack. I believe delrin can make a good nut, but i wonder about the ones in this machine when I know Dyna made nicer ones...

Mine did not come with the motors, so I will have to adapt mine on there. I'm going direct drive for simplicity's sake. I will have to make some kind of spider that mates up to the face of the original metal timing gears. I don't have a lathe so I can't really mess with the lead screw directly. If it turns out a timing system is better... I'll just make the machine limp through machining all that stuff and then switch it up. rather not spend the money on belts and gears tho.

Another observation: the design doesn't allow for tramming the spindle, tho i'm not sure the working envelope really warrants this anyway. thoughts? ever checked the tram on yours?

pics for the next post!

[Fastest1]

You are probably correct on the frosting verse scraping, I just knew they werent smooth. I have checked tram and it was very close, I did end up shimming the spindle mount with a piece of metal duct tape due to a small nod. I am truly only a hobbyist and seem to be more fascinated with the machines than the process. I have very little exposure to the real working enviroments and techniques (since there arent many women in there, I will stick to it as a hobby! LOL). My intent is too wire the spindle as it was, to have a manual or machine controlled spindle switch. I am just a little hesitant to wire the ground into the G540. I am allergic to magic smoke. Btw the simplest and IMO best coupler was done by Alex Cole on his conversion (I think) he used a helical coupler or made one that was threaded onto the leadscrew and controlled the preload on the thrust bearings. It was split with a clamping screw (not a set screw) to lock down once adjusted. It eliminated the gear entirely and allowed for direct drive. Btw why does everyone always want rpm control on a mill? I do understand the on/off but rpms are specific to tool size arent they? Why the need to change during a cut? I see for a lathe that would be important for finish quality or uniformity. I never had anyway to operate my machine besides the membrane controller, no other ISA cards or software were obtainable in my searches. My understanding was that it also required a dongle that are now long gone. Mine was one of the almost never used machines that had a limit switch error, I simply cleaned the switch and all started working. Then I tore it apart!

[Fastest1]

You could probably just hand tap a standard helical coupler.

[cyclotron]

So after looking over the other threads on nicer models of this machine i noticed some other differences:

the 2000 has metal gears at the ends of the lead screws

the 2000 does not have wipers

the 2000 does not have a support bearing on the nodrive side of the lead screws

whatever tho.

here are some pics of what i was talking about earlier.


There are two power supplies. one is rated 24v @ 4.5a and the other says 12v @ 4.2.

Right now I'm thinking that the original mill never had program control over rpms, just on/off via +5v to a relay. all the program/manual switch does is bypass the relay, sending power straight out of the box into the switch on the side of the spindle.

Fastest1,

The reason programed control of RPM is desirable is for tool changes and doing finish passes. That said, I think while on/off control will be easy to do with my own breakout board, rpm control can wait.

Your idea about tapping a coupler is a good one and i'll probably go that direction... What i really need to know is the thread size of the mounting holes in the original motor mount/thrust bearing bracket. The machine didn't come with the motors and all the hardware is gone so I can't take any direct measurements.

[cyclotron]

... just waiting on parts to show up...

helical couplers are on back order

I'll be boot strapping the motor mounts to get this thing up and running... I don't have any machine tools what so ever right now so my solution will be pretty rough looking.

[cyclotron]

hi all,

so here are some pics of my motor mounts. I cut them with a hacksaw and drilled them by hand. I'm still waiting on my helical couplers. In one of the pictures you can see about .2" of thread. I'll be tapping one end of the coupler to fit over that bit thread.

[cyclotron]

Well, it has been a while, and I'm back. So many months I left off with this retrofit at the point of coupling the motors to the lead screws. I never stopped working on it, I just took a break from updating this page.

Here is my solution... it requires no tapping.

So, if you take solid copper 22 awg wire (strip the insulation) and wrap it around the threads of the lead screw, it will bring the total diameter up to .251"
I simply slid on my old helical beam couplers and presto! no taping no nothing

So with the motors coupled up I was able to square away my electronics and cut something! So the the first thing I made was a collet wrench for the splined dyna quick change nut.

A lot has changed since that first project. I went from using an old copy of cambam on a partly working pc to using solid works with solid cam on my mac. I also switched everything over to my apple laptop running windows and a smooth stepper usb card. When I got the Smooth Stepper, I took the opportunity to make a real enclosure with neat wire harnessing. I also built an 80/20 enclosure (I got maybe 18 ft of that stuff all for 5 bucks at a scrap yard...)

So next up is to *finally* wire home switches, ad one of those MPG hand wheels to my control box, and install a coolant system. First up tho, I'll be swapping out the original quill spindle for a taig spindle and 1/4 hp motor. I have no idea how worn the old spindle is but it sounds bad... also it has no spindle bore, which is annoying (too much tool sticking out, can't use double sided endmills etc), and the motor is underpowered. I would love to hear if anyone has any pro vs cons about this procedure. I'm not really that attached to the quill or the speed dial.

Then I'll really be rocking with this machine!

Anyway, feel free to ask questions... I've only encountered someone using an apple for CNC control once before!

[Fastest1]

Great work. Show some pics of the enclosure too.

[cyclotron]

so the enclosure is nothing to write home about, I'll be moving in the next couple of months, so I have tried not to build anything too permanent.