Back to zero?

Hang on there, Pete. As you can read in this and other threads I myself had immense trouble in getting the machine to work acceptably but I am getting there step by step. Of course that's not the best way for anybody to do business, much less when the customer is - like you and me - a commercial concern who needs to get finished products out of the door.

My thinking on this is that I have invested too much money and precious time to throw the bath water with the baby still in it, I'm not going to waste all my investment by going out after a different mousetrap which may not turn out better after all, especially in this el-cheapo bracket of the CNC router market. So I'm sticking with what I have and do the best I can. If I have to insert multiple calibration points in my toolpaths then that's what I'll do.

If you and your colleague can be as stubborn and punctilious as I had to be, you'll get rewarded with a surprisingly good machine in the end (but keep careful watch all the adjustments so it won't jam on you!)

In my experience there is no cause to blame StoneyCNC, he's not the source of your troubles, the problem lies up-stream from him. Quite the opposite, as I said elsewhere he's the one who saved me from an expensive failure. I just wish he'd be more like St. Patrick and expel the snakes out of Stepcraft 😛

Meanwhile back at the ranch, I received the promised small industrial quality spindle from Rory today. It looks great but I have no power supply cable or time to test it until at least Tuesday next week.

Doug

Holy Shit, Doug! Rory has dragged you into the Dark Side of the Kraft :woohoo:

There is some good advice for you there Pete. I punted just over £3,000 for my "Steppi" with all the bells and whistles at the time except an automatic tool changer and several times have angrily regretted it, thought about selling it and a guitar and upgrading to a £5,000 commercial quality machine. However, I have persisted because I have mellowed a lot with age and I now believe that I understand its capabilities and inherent flaws well enough to appreciate that it WILL do what I require of it once the system is tuned and optimised.

Stick with it. It's easy for me to say I suppose because this is a long term hobby for me, not a commercial enterprise. :dry:

I'm not just saying this to be sycophantic to the main player here but Rory has been fabulous, just fabulous. Look at that amazing quality spindle he has offered to let me evaluate because of the repeat issues I had with the Stepcraft system. That's above and beyond normal customer service. He really cares and that's rare in my experience. Normally, people just want to sell you stuff and the after sales care is offered grudgingly.

Doug

Picking up on the thread where I'd left it, I decided to repeat that long test I had done before, the one where that had finish with a difference of several mm in Y-axis. First I gave the Y assembly a good check, and there was an difference of less than 1mm between the gantry pillars. This was annoying because that's one of the things I check often but there it was, so I exposed the belt which was quite taut but I removed it anyway so I could adjust both screws independently.

After enough head scratching the point was that the grubscrew on the farther assembly had come loose a couple of mil and the sprocket had a lot of slack! How did this come about I don't know, and I can't believe some Stepcraft agent came into my shop to sabotage my sprocket, so I'll assume it was me who failed to adequately screw the thing in during assembly.

After putting everything back into its proper place, I ran the aforesaid test, and I'm happy to say that 0-0-0 at start and at finish were satisfactorily coincident!

So one up for Stepcraft!

...and I can't believe some Stepcraft agent came into my shop to sabotage my sprocket, so I'll assume it was me who failed to adequately screw the thing in during assembly.

Don't beat yourself up, we had similar issues with slipping pulleys. (Parts would be uniform and consistent but the aspect ratio x:y would be out as the y pulley grub screws slid up to opposite edges of their recesses. Erm, probably.)

This is why:-
(a) Splines on shafts = Very Good
(b) Woodruff Keys = Good
(c) M4 Grub Screw on circular shaft = Bad
(d) M3 Grub Screw on circular shaft with pulley made from cottage cheese = Utterly pathetic, and shouldn't have made it past prototype.

Just my thoughts...

Owen S.

...and I can't believe some Stepcraft agent came into my shop to sabotage my sprocket, so I'll assume it was me who failed to adequately screw the thing in during assembly.

This is why:
(a) Splines on shafts = Very Good
(b) Woodruff Keys = Good
(c) M4 Grub Screw on circular shaft = Bad
(d) M3 Grub Screw on circular shaft with pulley made from cottage cheese = Utterly pathetic, and shouldn't have made it past prototype.

Much mirth. 😆

Couldn't agree more. Having to resort to a dab of superglue to stop an M4 grub screw vibrating out of its thread is a bit daft IMHO.

Doug

Superglue??? Duct tape no less!

Seriously, use Threadlock which is made for the purpose. Recently I made a similar comment in some humor forum that had no relation to any of this at all and I was taken to task by a guy who gave me a brainwash in anaerobic adhesives and why the cyanoglues (not his term!) in general distribution were inadequate for the job. In the end he told me he was the senior engineer in charge of the Loctite research lab 😆

Superglue??? Duct tape no less!

Seriously, use Threadlock which is made for the purpose. Recently I made a similar comment in some humor forum that had no relation to any of this at all and I was taken to task by a guy who gave me a brainwash in anaerobic adhesives and why the cyanoglues (not his term!) in general distribution were inadequate for the job. In the end he told me he was the senior engineer in charge of the Loctite research lab 😆

Funny! Yes, amongst all those people who know a little and like to aggressively expound it in internet forums, we often forget that senior engineers and subject matter experts visit forums too. How frustrating it must be for them!

BTW, I didn't put superglue on the threads, just a a dab on the grub screw flatted end.

Doug

Where did you get that awesome t-slot table?