-
Scam Alert. Members are reminded to NOT send money to buy anything. Don't buy things remote and have it shipped - go get it yourself, pay in person, and take your equipment with you. Scammers have burned people on this forum. Urgency, secrecy, excuses, selling for friend, newish members, FUD, are RED FLAGS. A video conference call is not adequate assurance. Face to face interactions are required. Please report suspicions to the forum admins. Stay Safe - anyone can get scammed.
Need Help in selecting a DRO for Craftex CX 601 mill drill
- Thread starter Ontarioal
- Start date
Also helps to know your budget.
Whatever you do, don't give anybody on this forum an open cheque book for stuff like that. Even if they are buying for you, your lady will kill you, and then she won't even be able to afford your funeral.
This is the one I bought late last year for my pdm 30 was pretty easy to install and works great for what I need it to do, second the lcd screen very easy to read.
Oh, that's not quite what I meant. I meant letting the boys on here loose telling you what to buy! We LOVE to help the other guy spend all his money.......
I like my Ditron very much. No complaints at all. I am gunna buy another one as soon as I can work out the details.
Other makes are good too. But I prefer to stick with what I already know how to use.
The biggest problem is negotiating a good deal.
So, what kind of questions do you have about getting a DRO?
Happy to help. Very happy with mine.
Here is the complete thread on my install. Lots of problems, but all solved in the end and very happy with the end results.
Thread 'Installing a DRO on a Hartford Bridgeport Clone.' https://canadianhobbymetalworkers.com/threads/installing-a-dro-on-a-hartford-bridgeport-clone.4852/
Happy to help. Very happy with mine.
Here is the complete thread on my install. Lots of problems, but all solved in the end and very happy with the end results.
Thread 'Installing a DRO on a Hartford Bridgeport Clone.' https://canadianhobbymetalworkers.com/threads/installing-a-dro-on-a-hartford-bridgeport-clone.4852/
Magnetic are more compact and easier to trim to length. Perhaps I could even say downright trivial to trim. Glass isn't that hard but can bite you. Not one guy on here has been bitten based on my research. Those guys on other forums don't seem to be as careful....
But even if you set trimming aside, magnetic takes up less room and my testing shows its pretty forgiving of both alignment and gap.
If you get longer scales than you think you need, you can always trim magnetic. Easy peasy.
Proper length is full travel plus the length of the read head including wipers. You can download a spec sheet from most sellers.
My advice is to carefully locate your scale and read head before you order. I didn't, and it bit me. I ended up having to move one scale because it wouldn't go where I wanted it to go. It worked out in the end, but it was stressful. In my case, the issue was cable stress relief - no place to put the clip.
It's also good to know that a scale that is too long is not usually a problem.
Most guys say 5 micron is plenty. Some complain about digit jitter with 1 micron. But they upgraded me to 1 micron for free, so.... Why not!
To be honest, I set my DRO Readout box to display just 4 digits so I'm not really using the scale capability, but I have no jitter. Yet, it's good to know that I can go to 5 digits if I ever want to.
The Ali website is sooooo confusing. I believe it was originally designed to sell women's clothing.
You have to select size and colour to get the different options.
Or you can start a chat with the store. That can be confusing too. But after you get used to being called darling and sweetheart it starts to get easier.
When I got mine it was confusing at first also, but all I had to do was order the pieces separately to get what I wanted. Sometimes you just have to read things over a few times before it makes sense . The tricky part is making sure you measure your travel correctly to get the right length scales.
Hi @Ontarioal
For your reading pleasure I propose to you the following:
TouchDRO's (Yuriy's) DRO Resource Guide
Touch DRO's DRO Scale Selection Guide
TouchDRO's Understanding DRO Scale Parameters Guide
On those and related pages you will find a ton of useful information applicable to selecting the scales that best suit your needs whether you're interested in Yiuri's DRO or not. You will also find a ton of information about the TouchDRO application which runs on an Android tablet if that is of interest.
I am working down the path toward putting TouchDRO on both my lathe and mill. TouchDRO covers the feature set of Ditron & Aikron. FWIW that's one tablet between 2 machines (wireless) since I can only run one at a time!
I have just ordered 6 scales from Ditron so here's my take. Learn as much as you can about scales in general per above then learn as much as you can about their products from Ditron's actual web site. The AliEx pages are suboptimal.
Look for scale type and outline. They come in regular and slim formats, glass & magnetic. They also come in 1um and 5um resolution but you can kinda ignore that with Ditron because they seem inevitably to offer to upgrade you for free. The inflection point for me was when they eventually mentioned the fact that despite knowing I was in Canada, the price offered was in USD. I went quiet for a while to re-do my sums and they came back with free upgrade. I think they like to use it as a way to sweeten the pot if your interest drops off.
Before going to Ditron I went to the Aikron (very good and clear site!) web site and priced up their offering so I had an idea what the price and specs. would be. I then posed my specs to Ditron via their chat window on one of the AliEx pages and the chase was on. Do that vs. trying to piece together something from individual AliEx pages which leave something to be desired. Get everything figured out with them before paying then they send you to a "proxy" page they put up just for you to do your transaction.
On their AliEx pages everything is a certain price and "free Shipping", once you get chatting, shipping is extra but the prices are better, lower than Aikron by about 30% when shipping is included. I find Aikron's pricing disappointing because their site and data is very good and the product is coming from the same market. They also responded quickly by E-mail even though they were supposedly closed for the new year holiday. When I questioned the price they offered me the 10% new year sale which still left them 20% higher - that and the resolution was mostly 5um so they became second choice.
OK, back to Ditron. @Susquatch has mentioned that in his first buy they were keen to get the sale in by month end and they mentioned this to me also so that may be a lever or it may also be a way for them to push you for the sale. They are not shy to ask you if you're ready to buy now!
Scale sizing. Aikron & Ditron both give drawings depicting scale sizing but the one factor not on the drawings is what Ditron calls the "Safety Space" which is the travel allowance for tolerance and mounting fit-up in addition to machine travel. You size scales by the travel distances of your machine axes and they add their Safety Space to come up with a final size. I added some space above this.
This is the exchange I had with them:
I see a dimension on the scale drawings for overall length based on travel, I have provided machine travel hard limits, how much "extra" travel is permitted for each scale type to account for positioning on the machine and tolerance?
Ditron:
"For DC11 linear scale , there have 20mm safty space , that is mean , if you travel length 685mm, the max reading on the display = 705mm
For slim linear scale , only 7mm
For magnetic scale , if you order 130mm , that is 130mm travel length"
(DC11 scale is their description for a STD size glass scale (DC10) but with 1um resolution but it's hard to find that on Ditron's site.)
So you see that the Safety Space you get is different for each scale type and whether it is a slim or regular profile scale. I ran my axes to the end stops and measured plus added some wiggle room for myself on top of their Safety Space, about an inch. Linear scale is their name for a glass scale. You could mock up the sizing on cardboard if you need to visualize the mounting. I even made a wooden mock up of one scale because it's in a very constrained space.
When you get down to tying down the specs with Ditron I suggest you spell out exactly what you want, scale by scale, e.g.:
"Scale 1: Linear scale, DC11F-435mm of machine travel, 1um resolution. $68"
In this case "machine travel" is my number including my additional safety space.
Hope all this is useful! Keep us up to date on how you make out.
D
Hey @Tecnico & @Ontarioal
Tecnico's write up is awesome!
My assessment of their safety space goes like this. The read head must he able to travel back and forth between the two end limits plus a wee little bit for installation errors. In machining terms, that means that the sum of the scale on both sides of the read head equals the full travel. In other words, the scale length isn't just the travel, it's the travel PLUS the length of the read head and its wipers. This extra length is what I came to believe Ditron called their safety space. Obviously, it varies with the read head dimensions.
In practice, you need a little more than that to avoid installation problems. I just added another centimeter on both ends because I knew that would fit. In hind sight I might have added 5cm if I had the room because I did end up close to the end in one case. Besides, magnetic scales are easy to trim.
I personally do not think that 1 micron slim scales cost Ditron any more than 5 micron regular scales. They just charge more because they can. For me, it was a negotiating point.
Although my memory might be failing me, I never had the sense that they had month end numbers to hit. But I did get the sense that they had quarter end targets. If they volunteered that to Tecnico, I'd be thrilled - and maybe pissed that I didnt already order my lathe system at the end of January. I've been aiming at March 31st. But such is the way these things go.
Another little piece of info. I got a small strip of Aikron magnetic scale from @Xyphota a while back. I plan to install it on the inside of my cross slide so I don't need to worry about damaging the scale with flying swarf or the tailstock or about any lost travel of the carriage. Ditron wanted too much coin for their scale and wouldn't sell it without the aluminium carrier. My system is the slim scales. The Aikron is smaller still by quite a bit. It does work with my Ditron system, but I had to set the resolution to 1/2 micron to get the right output. Something is funny there but it does work and does repeat.
Also, using the auto zero lost power function of the Ditron turned out to be quite confusing. Apparently the tape has zero points encoded in it at regular intervals. You can save these intervals and restore them even after a power outage. I do not know how an Aikron or whatever other scale would affect that as I have not installed the Aikron magnetic strip yet. Even if it does have an effect, it will only be for data recovery after a power loss which I don't think I will care about. I am just a hobbiest - production efficiency means little to me.