Building a Drag Engraver by c. raynerd

Gallery, Projects and General > Project Logs

<< < (4/6) > >>

andyf:
That's great, Chris :clap: . You must be really pleased with the machine.

Looking at Bob's portrait, I think he's the guy who begs for spare change outside one of my local supermarkets....

Andy

HS93:
Looks good , handy that you can get the art work. what tape did you end up with, and what is the tip made of that does the engraving ?

Peter

raynerd:
Peter: it is a diamond tip and cost me about £16. In the pictures in the first post, you can see the diamond tipped 1/8" steel shank inserted into the lower section of the drag engraver. The tape is unknow from my father-in-law who uses the same type at work for an important temporary holding job. It is much much better than the stuff I had.

Andy - yes, he must be the same Bob who sits outside our Tesco asking for loose change.

Phil - the video is deceptive, I have both of the original bars still attached (there is one above the top on on the video) and the linear rail which really supports and braces the whole lot. It has done the trick 100% as it not only supports the z axis, but it also supports and braces the two sides. It does mean I lose about 4mm of z height but for a solid machine, I can totally live with that.

Regarding the TB6560 - well I have a setup that works. Firstly I need to partly apologise to the TB6560, it is easy to get onboard with the TB driver bashing cart! I`m currently set to 24v, 75% current, fast decay rate (??), 1/2 stepping and it seems to be working just fine. Half of my problem was that the motor spindle is directly attached to the leadscrew and there is about 1mm of endfloat in the motor that I was thinking was missing steps. I took this up with a thrust bearing and its much better. However, if I change any of the settings and I start missing steps. My motors are 2A and ideally I`d like to set the 3.2A driver current to 50% but I`m having to run them at 2.4A by setting the driver to 75%.

Also, with 200 step/rev and 1/2 step (current setting) = 400 steps/rev and with a 2mm pitch leadscrew = 200 steps/rev. That isn`t very good resolution in my opinion but if I change this to 1/8 multistepping my motors start to run really slowly, noisly and jerky. I don`t know why and I don`t seem to be able to cure it. I presume I would get a better resolution at 1/8 stepping.

There is quite a good thread on cnczone about trying to sort this TB6560 drives out. I`ll probably give it a go over the next few weeks:
http://www.cnczone.com/forums/general_electronics_discussion/110986-how_i_fixed_my_chinese.html

DaveH:

--- Quote from: HS93 on April 04, 2012, 09:39:07 PM ---what is the tip made of that does the engraving ?
Peter

--- End quote ---
Peter,
The tip is made of carbon :lol: :lol: :lol: " I'm a wealth of knowledge ot times" :D
:beer:
DaveH

John Stevenson:
Chris, I'm having to run my TB board in 1/2 stepping mode.
Won't run in anything else makes all weird noises and you cannot calibrate it correctly.
It differs from job to job, 1/2 stepping seems to work OK and on the little engravers it's on it works OK.

That is setup for drag engraving and has done a few test pieces, just need to get it setup to do a small production run.

John S.

Navigation

 Message Index

Go to full version