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lucan07
21-03-2016, 09:58 PM
Been busy of late and the conversion of the Seig X1LP super has been succesfull to date, now time to build something from scratch. Started badly as I couldn't resist a bargain and came across a couple of sets of Rails Bearings and screws at the right price Sub 300 delivered. So my starting point now is:
4@ SBR20-300mm Linear guide
4@ SBR20-600mm Linear guide
4@ SBR20-1000mm Linear guide
24@ SBR20UU Linear blocks
2@ SFU / RM 1605-350mm- C7 ballscrew with end machined
2@ SFU / RM 1605-650mm - C7 ballscrew with end machined
2 SFU / RM 1605-1050mm- C7 ballscrew
2@ with end machined
6@ BK12 support for ballscrew

6@ BF12 support for ballscrew
6@ Couplings
Major considerations, I have a workshop in a spare room in my first floor flat so everything gets carried up and down as required, and I try to limit noise to be considerate to neighbours. Been looking at Fusion 360 which I find simple and straightforward to use with the Seig conversion so knocked up a quick mock up of a machine to get some comments and advice sure there are lots of traps I have fallen in to pictures below .
My requirements call for a 700x400mm work area and max 100 mmZ axis. Not included in pictures are 2 SFU / RM 1605-1050mm- C7 ballscrews driving Y axis, either 1 or 2 SFU / RM 1605-650mm - C7 ballscrew driving X axis and single SFU / RM 1605-350mm- C7 ballscrew driving Z axis with a Chinese 2.2 water cooled and VFD. A lot of my strength I am relying on a solid base I intend to bolt whole thing solidly down onto a welded steel framed table with a solid cast iron top.
1798417985179861798717988

Material wise two bed sides are100x100x10mm T section which can be backed up by another 25-35mm plate without losing work area, X and Z main components 25mm and 30mm Ecocast, first draught so nothing much fixed apart from overall size, my idea is based on ease of build, welding in the flat is not an option.

JAZZCNC
23-03-2016, 09:45 AM
Not sure what your trying to achieve here.?

If you have Cast iron surface plate why do you need the lower frame.? Just bolts the rails to the Cast iron top.

The gantry and Z axis setup are both very bad idea. The rails on back side of thin plate will flex and resonate. But worse is the length of the top and bottom bearings plates make long lever that will flex like crazy. It will affectively be like putting Z axis and spindle on end of diving board.!!

Suggest you scrap the whole tall sided Gantry idea and go with better setup of building up the sides from the base to give gantry clearence you need and sit rails on top. This can be done with steel tube or aluminium profile.
Then gantry again made from tube or profile sits directly onto the bearings giving a very strong and simple setup. To give you some space back make bearing plates that offset the gantry back slightly and mount the rails on top n bottom. Put ballscrew on backside with Z axis top bearing plate extending back so can connect with ballnut.

This setup will be much stronger and easier to build.

Also forget buying Ecocast or ground tooling plate with these rails because the base of them will have more error than normal aluminium plate so it's wasted money.

lucan07
23-03-2016, 11:15 AM
Ecocast already dismissed offered some stock from a company due to close.

Idea behind lower Plate 3x1 1/4" to make unit stable if moved off base bolting rails straight through plate and cast top so idea to have some rigidity while building off plate as thats being ground.

Raising sides and shortening gantry was considered using 6x2 box section between cast plate and mounting rails shortening gantry sides considerably sounds like this may be worth while also removes bottom plate.

As I already have all of the Angle and T sections that I used in original design (reasoning behind much of my design) and have been offered all the plates in original design for 100 inc vat for 6082 grade stock will have to see what is available have to look will be buying more depending on space in my lock up when I see the total stock today, if nothing better available backing the 1x6 635mm X axis with available 3x1x1/4" angle would allow top bottom mounting X rails and firm up cross beam.

Back to the Drawing board and try again, thanks for the input.

lucan07
23-03-2016, 04:33 PM
Had a quick look at design and Knocked up version 2 this is a draft few peices omitted till I collect stock material acquired today like side of gantry just turned original on side for now and nor bothered actually mating same to bearings more for concept than actual design, also brackets mounts for screws, motors etc missing.

Hopefully overall design and more importantly rigidity improved pics below sides now 6x2x1/4" Aluminium Box, cross member on X axis now original 150x30mm Backed by 2@3x1x1/4 Angle faced to 75mm x 25.4 to fit.

lucan07
06-04-2016, 10:53 PM
First chance to do any work on build today half a day off so made a start, first job decide what to do about the steel and cast iron base I intended on using, top has been ground flat and its ready to go but Base weighs in above 3Cwt and Top just over 4Cwt all to be carried upstairs.

For time being I am going to put base into my lock up and try a different base to as all work in flat is likely to be lightweight, I will be selling my flat and buying a property with a workshop so the base will either be used then with this machine I originally designed for it or with version 2.0 which I have no doubt will be built.

So alternate base? As welding out of question in flat I have gone for simplicity, two sheets of 25mm MDF (http://www.diy.com/nav/garden/garden-buildings/sheds-garden-storage-workshops/a-9275221) to make my base, bed laminated 75mm MDF whole base sealed glued and screwed, it's solid, time will tell if its solid enough, I cannot see any problems with type of work it will do whilst in the flat.

As base was drying I decided to drill and tap side rails which are 6"x4"x1/4" Ali box I used M6 with 30mm washers to attach rails to bed, M4 to mount external supporting ribs 300mm 38x38x6mm T section, M4 again to mount 20mm supported rails quite happy with the afternoons work, rails have a little adjustment available and I intend on locking them down with either loc-tite or epoxy when final adjustments made, currently as close as I can measure having just dropped them on and pinched up they are within 0.5mm over 1000mmm on the parallel.

Couple of pics below showing latest design and progress.

lucan07
07-04-2016, 10:21 PM
Grabbed a couple of Hours this afternoon again and made a start on the X axis, by far biggest lump of aluminium thats been machined on the Seig since conversion, think I upset it when I put the fly cutter on to true and parallel top and bottom to accept rails, it started spitting needlles at me with a vengance!

635x150x30mm 5083 Plate backed by two lengths of 3x1X1/4" angle which was drilled and plate drilled and tapped for M4, top and bottom trued, paralleled, drilled and tapped M4 again to mount rails.

Stomache was thinking throat had been cut so stopped now to eat, just two ends of crossmember to machine true and parrallel and it is about ready for ends/gantry sides to be mounted, I am thinking pocket the gantry sides 1/16" to accept crossmenber for strength and ease of alignment doing so also positions them nicely to centre of Y axis bearings.

Spindle and VFD just arrived got a good deal on these 146 delivered and they look ok, now I'm cooking with gas.

Build is going OK a good start with 9 hours in its starting to take shape, if you sort of squint and look sideways that is, as my old dad always said "a blind man would be glad to see it"!

sinnsvak
08-04-2016, 02:00 AM
Thats a solid piece of gantry! Must weigh a bit?

Have not tried a flycutter yet, but I suspect the same thing will happen when I do :)

Have fun with your build!

lucan07
08-04-2016, 07:11 PM
Have a Y and now almost an X and I have a few spare hours over the weekend to come up with working drawing for Z and start machining. Impressed with Fusion360 so far simple to use and with a little tinker of the code before running mach3 the little seig conversion goes about its business with little complaining, nice to get some decent size lumps on it to cut eventually and make some decent chips.

Ended up pocketing 4mm each side to centre the gantry raiils onto Y axis bearings. the work area I will be able to use now confirmed as minimum 780x450x100mm

18135

lucan07
12-04-2016, 11:45 PM
Managed to get a couple of hours in over the weekend, and made some progress with Z axis, now have three smooth free moving axis and screws mounted for Y and Z still waiting on delivery of some parts so limited to working with parts already available. Time to start thinking about motor sizes required, being a novice I was surprised by the weight accumulation with the 20-30mm 5083 plate, rails, ballscrews etc used so need to work out totals and ensure adequate power from steppers drivers etc.,

lucan07
28-04-2016, 10:14 PM
Progress being made not been able to keep up with posts as everything has been done in snatched moments as and when the free ones occured, all wired and connected ready for a test run tomorrow work permitting. Went with 5 axis BOB, 4 x DM542 4.2a drivers, 4 x 425oz Nema 23, 2.2kw HY VFD and Spindle, linkage I used 2:1 ratio from motors to 1605 ballscrews, power supply a pair of 36v 9.7amp units I had, option to swap in a pair of 48v 10.4amp will be available soon if it will be beneficial.
18337

JAZZCNC
29-04-2016, 01:20 AM
Why would you go with 2:1 ratio on 5mm pitch screw. This will be far too slow for router.

Also to make matters worse your only running 36V which means your your steppers are under performing by far margin, even with 48Vdc they will be running slower than they are capable of doing.

With 36v you'll be lucky to get 1000rpm and have any torque left. With 5mm pitch screw at 1:1 ratio that would only give Max feed rate of 5000mm/min. This halfs with 2:1 ratio. 2500mm/min is way to slow and this is Rapid speeds. Your actual cutting feeds will be in the 2000mm/min range which is way to slow for router.

Dump the ratio or better still swap the Pulleys around and go with 1:2 ratio. Up the voltage to 48v ASAP.

lucan07
29-04-2016, 08:17 AM
My mistake ratio is 1:2 30 teeth on Motor 15 teeth on Ballscrew, I already had 2x36v power supplies on the shellf and have 2x48v being removed from machines being disassembled shortly so having deep pockets and short arms that is what I have used. The DM542 are only rated to 50v I believe so close to the limit available to me using these drivers.

Lee Roberts
29-04-2016, 10:09 AM
Looking good so far!

I'm also using 542's though not the digital ones, I wouldn't go above 45v as you need to leave some head room (10%).

Stick with 1:2 and call it good/done personally.

.Me

lucan07
29-04-2016, 10:13 AM
Cheers Lee I am sure the 48v supplies adjust on a pot same as 36v so shouldn't be a problem.

Lee Roberts
29-04-2016, 11:57 AM
Cheers Lee I am sure the 48v supplies adjust on a pot same as 36v so shouldn't be a problem.
Cool good luck with that then, interestingly I've just ordered some moxa dr-4524's to use for my control gear, these have an adjustable pot too, what I can't find out is just how much range is in the adjustment.

How much adjustment are you getting from these smps units? I'm after one I can bring down to 12v but with around 60w as it's to power a pc.

Edit: Ahh OK just seen it gives you the range on the meanwell units in the datasheet...

.Me

lucan07
30-04-2016, 12:07 AM
So much for a day off only ended up working till 9pm, had to plug it in a try it when I got back, spindle fine, Z axis fine, Y axis with A slaved no problem, X axis just a rumble and rock from motor, too tired to even think about it tonight can't be too serious it didn't go bang! The two working axis have proved already it has all the speed I will ever be able to use in the flat and then some if it lived in a shed the shed would have been rocking. Would have been nice to have it all work but 4 from 5 is better than a kick up the backside.

Lee Roberts
30-04-2016, 12:23 AM
So much for a day off only ended up working till 9pm, had to plug it in a try it when I got back, spindle fine, Z axis fine, Y axis with A slaved no problem, X axis just a rumble and rock from motor, too tired to even think about it tonight can't be too serious it didn't go bang! The two working axis have proved already it has all the speed I will ever be able to use in the flat and then some if it lived in a shed the shed would have been rocking. Would have been nice to have it all work but 4 from 5 is better than a kick up the backside.
Nm your not the only one as I've had to sit around not doing much today too :(.

Early start in the morning? Post a video of her jogging about with a big cheesy grin of joy? Go on spoil me you know you want to [emoji16]

Will you share with me where you got your spindle and VFD from, that is a good price maybe I was looking in the wrong place but I was seeing 300 for the 2.2's...

Lee

lucan07
30-04-2016, 01:16 AM
Will you share with me where you got your spindle and VFD from, that is a good price maybe I was looking in the wrong place but I was seeing 300 for the 2.2's...
Lee

No problem Lee Fleebay had a 20% off everything offer for a few hours on 6th or 7th of April so I grabbed the VFD and spindle then, full price is 182 ans I got 36 discounted. Still has original offer ships from Germany about 5 days.
http://www.ebay.co.uk/itm/281752349253?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I have set up cooling in a 25ltr can of distilled\deionised water removed 10 ltr and added 5ltr of Mono Propylene Glycol to prevent any algae etc, Trying a new idea with pump though a minature 8.5w with 10ft lift seems to be ideal and totally silent.
http://www.ebay.co.uk/itm/391398992370?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Great thing is fits into can easily so drill three holes in cap 2x9mm for hose and 1x3mm for cable drop pump in and screw on cap sealed unit, return pipe above water and only noise is the trickle of water from the set up if you listen carefully.

Will post some video as soon as last motor sorted while tuning Y and slaved A tweaking it up, at 5m pm with 2000 accel the whole thing began to walk/run accross the room quite a weight on gantry, so I am going to have to machine either keys or flats or get some decent resin to lock timing pulleys securely, I've tapped 2 x 4mm grub screws into each pulley but would not trust them to hold at the speeds it was moving especially on round end of Ballscrew. I can't see torque or speed being a problem apart from trying to tear my hard work to pieces if I push it to hard.

Another bargain I found may be of interest was the spindle mount under 20 delivered from HongKong and it arrived in 6 days was thinking about machining a large bearing mount but at that price not worth while.
http://www.ebay.co.uk/itm/131772480839?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

lucan07
30-04-2016, 08:31 AM
Been thinking about my pulleys and how to secure them over breakfast, it may be obvious that I have little or no engineering experience so is this an acceptable way to lock pulleys securely.

My problem:
Each pulley is drilled and tapped and fitted with opposing 4mm grub screws, but motor and ballscrew shafts to which they are mounted are both round so not an ideal situation and I sure they would eventually move at some point.

My intended solution:
To drill into the pulley and shaft from the end effectively making a semi circular keyway into which I can insert a pin, I am thinking that 2-3mm drill giving 1-1.5mm semi circular key slot in both shaft and pulley would be enough to lock these connections and prevent slippage.

I know keyways tend to be slotted and have vertical sides, but as an amateur who did not consider the amounts of torque involved moving weight at speed
a) is my solution viable?
b) is 2mm or 3mm with a steel pin sufficient to do job?
c) is there a simpler way I haven't considered?

Clive S
30-04-2016, 08:56 AM
Each pulley is drilled and tapped and fitted with opposing 4mm grub screws,From my understanding the screws should be at 90' to each other also if you clip a little bit of copper wire off and flatten it then slip it down the grub screw hole it will grip the shaft better.

Loctite will also hold them on.

Neale
30-04-2016, 09:00 AM
Drilling into the end, cutting both shaft and pulley, is an established technique but you will find it difficult to do accurately with an aluminium pulley as the drill will start to wander. Also, it's a mistake to drill for grub screws at opposite sides. You are now balancing the force of one grub screw against the other. Much better to drill at 90-120 deg apart, so both grub screws and the bore of the pulley grab the shaft. That might give some useful extra grip. You could just file a small flat on the shaft for one grub screw to bear against?
Good luck - I haven't reached this point on my own machine yet!

lucan07
30-04-2016, 09:26 AM
Drilling into the end, cutting both shaft and pulley, is an established technique but you will find it difficult to do accurately with an aluminium pulley as the drill will start to wander. Also, it's a mistake to drill for grub screws at opposite sides. You are now balancing the force of one grub screw against the other. Much better to drill at 90-120 deg apart, so both grub screws and the bore of the pulley grab the shaft. That might give some useful extra grip. You could just file a small flat on the shaft for one grub screw to bear against?
Good luck - I haven't reached this point on my own machine yet!

The pulleys are not aluminium they are Zync plated steel quite solid so I may try a test on the end of one ballscrew I have a small drill stand that I use for holding a tapping aid that I can fix in place with Lube ands patience it should be possible without to much wandering.

Davek0974
30-04-2016, 09:40 AM
Drilling in from the end is a good method, if at all possible, drill in and tap a thread - M3 or 4, then fit grubscrews, that way the pulley is secured both directions - axially and radially. You will only get away with it if both metals are similar hardness, my concern is the hardened end of the screw - if one is softer the drill will wander into it.

And yes, grubscrews at 90 or 120 degrees only, never opposite and only two screws, always file/grind a flat on the shaft for at least one screw, better still drill a little divot the same size as the tip of the screw.

lucan07
30-04-2016, 09:55 AM
You will only get away with it if both metals are similar hardness, my concern is the hardened end of the screw - if one is softer the drill will wander into it.

The shafts will be harder than pulleys, I could Dremell a half round into shaft and use mill to match this on pulley would not be identical in all honesty but should be close enough to be able to run a M3 tap. Alternatively with opposing grub screws would I be better to drill through shaft completely and use a split pin

And yes opposing grub screws an amateurs mistake lesson learnt will remember that once is a mistake twice is stupid!

Decision made I had seriously under estimated how hard the ballscrew material was going to be.

Significant flat ground on one side and loc-tite to ensure grub screws stay put will be my plan of attack for now, just dremelled first one and grub screw replaced by an allan head A2 stainless machine screw should be sufficient to prevent rotation and lock pulley in both directions.
18340

lucan07
30-04-2016, 11:46 AM
Got ten minutes to inspect the plug on X axis and it had a problem caused by old age and drugs, I got older massive doses of steroids prescribed eyesight went to crap, some plonker managed to rotate pins by 90% when soldering late the other night, easily fixed glad I didn't use a 6560 for this build the driver would have gone pop and I would be soldering a new TB6560AHQ IC into the board and tales of magic smoke would be told.

lucan07
02-05-2016, 01:13 PM
Bit of progress made over the weekend sorry to say weather was nice so my bikes took most of my free time been neglecting them too much lately they need riding and I need the exercise getting old, London Surrey 100 end of July and Box and Neath hills are both killers if you are out of shape and practice. However fixed problem of slipping pulleys before it occured, a bit of testing/tuning first cuts a few slats of 25mm mdf which I have decided to use for first sacrificial bed, had a selection of 2020 off cuts laying around from printer builds etc so using these for clamping t-slots gives me 5mm to skim as needed. Using 6mm Router bit 1st DOC 3mm 2nd 6mm 3rd 12mm MDF using 12000rpm and 1500mm pm feed no problems with cuts. I have used a BOB I was given I think its a cheap chinese import and I appear to be having occasional problems, axis will refuse to operate in one direction, jogging a different axis then frees the original axis to move as required so another BOB on its way, double checking wiring next on to do list, all wiring is CY shielded cable currently all mounted in small pc tower case whilst waiting for cabinet to arrive so may just be everything to close for comfort. VFD is mounted well away from everthing else.

lucan07
03-05-2016, 12:45 PM
A little googling indicated that problem may well be with me using opto isolated Bob to feed opto isolated drivers but this was not conclusive, however a post on Mach3 forum got the same answer from on of the Mod's Tweakie who I class as a reliable source so hopefully new bob without opto isolation will solve my problems with axis stalls.

Davek0974
03-05-2016, 02:29 PM
I have the same setup and asked the same question to a lot of suppliers - the answer was that using opto isolators to drive opto isolators was no issue at all and is very common as it protects both ends of the system.

Clive S
03-05-2016, 02:41 PM
A little googling indicated that problem may well be with me using opto isolated Bob to feed opto isolated drivers but this was not conclusive, however a post on Mach3 forum got the same answer from on of the Mod's Tweakie who I class as a reliable source so hopefully new bob without opto isolation will solve my problems with axis stalls.I have not seen Tweakie post but I am pretty sure that using double opto's won't make any difference to an axis refusing to go in one direction or the other. I would check the cables for loose connections.

lucan07
03-05-2016, 03:06 PM
I have not seen Tweakie post but I am pretty sure that using double opto's won't make any difference to an axis refusing to go in one direction or the other. I would check the cables for loose connections.

post in question attached with reply had seen this mentioned elsewhere all other cables checked have replaced Bob alone and problem is now solved, in short if not problem on occasions why did tweakie come up with response straight away without opto bob or drivers mentioned, why did non opto bob solve problem?





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Re: Router/Mill Design & Build (https://www.machsupport.com/forum/index.php/topic,32208.msg225825.html#msg225825)
Reply #12 on: May 02, 2016, 06:30:42 AM



Bit of progress made over the weekend sorry to say weather was nice so my bikes took most of my free time been neglecting them too much lately they need riding and I need the exercise getting old, London Surrey 100 end of July and Box and Neath hills are both killers if you are out of shape and practice. However fixed problem of slipping pulleys before it occured, a bit of testing/tuning first cuts a few slats of 25mm mdf which I have decided to use for first sacrificial bed, had a selection of 2020 off cuts laying around from printer builds etc so using these for clamping t-slots gives me 5mm to skim as needed. Using 6mm Router bit 1st DOC 3mm 2nd 6mm 3rd 12mm MDF using 12000rpm and 1500mm pm feed no problems with cuts. I have used a BOB I was given I think its a cheap chinese import and I appear to be having occasional problems, axis will refuse to operate in one direction, jogging a different axis then frees the original axis to move as required so another BOB on its way, double checking wiring next on to do list, all wiring is CY shielded cable currently all mounted in small pc tower case whilst waiting for cabinet to arrive so may just be everything to close for comfort. VFD is mounted well away from everthing else.





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Re: Router/Mill Design & Build (https://www.machsupport.com/forum/index.php/topic,32208.msg225826.html#msg225826)
Reply #13 on: May 02, 2016, 07:18:20 AM



Nice work sir. Let's hope that changing the BoB cures the axis one way problem (issues such as this can occur when using an opto-isolated BoB feeding into an opto-isolated driver).

Tweakie.

Clive S
03-05-2016, 05:20 PM
post in question attached with reply had seen this mentioned elsewhere all other cables checked have replaced Bob alone and problem is now solved, in short if not problem on occasions why did tweakie come up with response straight away without opto bob or drivers mentioned, why did non opto bob solve problem?
Well obviously you have found a trusted source but I still don't think that this is the cause of the problem and you will have to ask Tweekie why he came up with the response.
I also notice that you are mirroring all your posts over there so why bother asking questions here?

lucan07
03-05-2016, 05:36 PM
Asking questions on different sites is likely to have different people responding, just wondered if anyone else had come across this problem, couple of posts I saw elsewhere that were unconvincing to me, I was as skeptical as you that this would/should cause any problem. The fact that a trusted source came back with identical response lead me to believe there is something in this which I do not understand, therefore ask question where I think advice will be most reliable and well informed. I will ask Tweakie his reasoning behind the response now problem has been resolved and pass on information I am as puzzled a you as to how this can affect operation across two seperate circuits.

lucan07
04-05-2016, 08:15 AM
Checked back with Tweakie regarding this and no explanation available response was

"I have not looked into the reasons behind opto - opto problems, perhaps it's timing related, it is just that this issue has been reported on the forum many times in the past. Tweakie."

so no nearer to knowing the problem, unfortunately the Bob I used I was given new and sealed so no real information on it, but out of interest I connected it on the Seig X1 conversion which does not have opto isolated drivers and it worked perfectly. It may just be the Bob is a poor quality cheap import possible others reported are same, more may just have been replaced as faulty, it will remain a mystery for now.

Clive S
04-05-2016, 08:39 AM
Checked back with Tweakie regarding this and no explanation available response was

"I have not looked into the reasons behind opto - opto problems, perhaps it's timing related, it is just that this issue has been reported on the forum many times in the past. Tweakie."
Ok So not quite the response you quoted !! really just a comment from him. (I have read many of Tweakie's posts over the years and do respect him but in this case he only made a comment and not a statement) But glad you have it sorted.

I think you will find that a lot of these cheapo bob's don't work well with modern pp on pc's because the pp will only output about 3.5V the older one's output 5V this means that the bob has to convert the 3.5v back to 5V to get the correct logic. This is a known and well documented problem with cheap bobs.

I have said this for the benefit of others reading this post and thinking double opto's won't work.

lucan07
04-05-2016, 10:06 PM
And award for plonker of the week goes to ME!! rushed back so I could skim the bed before it got too late, I had trammed it in on an old offcut of ply last night. Set it up to face at 1.5mm DOC at 1.5mpm 6000rpm and it glided around leaving a nice clean finish, straight edge and a CREE to check and a blind man would have been glad to see it. http://machsupport.com/forum/Smileys/default/shocked.gif Who decides wants to play some more and take just 0.2 to see how it goes, fired up the spindle and thought I would try the new hand control thats sat here for a week, DAMN straight down and 1mm ding in the freshly skimmed bed, well it can stay as it is for now until I feck it up again!!! Anyway have to remove the grease nipple on bottom Z axis bearing to skim it as it holds just off the edge.