Lathe DRO SCALE question.

[Suzuki4evr]

Hi guys.
I purchased a DRO for my mill a year ago and I am looking into purchasing a DRO for my lathe now. From what I read so far from posts here on H-M is the best way to go concerning the scales,is to go with magnetic scales for a few reasons. One of those are they can't get contaminated like your linear glass scales,but..... they are a bit more expensive.

So my question is to the members who does have DRO's on their lathes and have glass scales. Is contamination a BIG problem asspecialy if you use flood cooling like I do, or can is it not that big deal?

My lathe has a 1500mm y-axis travel,and that is why I am asking because a mag scale that length would be pricy. I am going the Aliexpress route like before because it fits my budget. I will most probably get a slimline scale for my cross slide and the standard one for the y-axis.

I am very interested in the members answers on my question, because it will influence my decision.

Thanks guys.
Michael

 

[Winegrower]

My mill has had glass scales for probably 20 years, never a hiccup. My lathe has magnetic scales, and I'm suspicious, but can't prove anything solid. I suspect that small particles can get near the magnetic domains and distort the interpolation a bit. When you try to repeat, it's different.

I hope this post doesn't sink the whole magnetic scale industry.

 

[mksj]

I have installed/used both and never had a problem with either of them, and I trust both equally. Magnetic scales still should use a cover or minimize exposure to swarf. Magnetic scales are easier to install and less subject to error from misalignment. Occasionally a small piece of steel swarf might get between the reader and track and could cause a reading error, haven't seen this but a few reports. If coolant I would go with magnetic over glass, in particular the cheaper Chinese glass scales have poor lip seals. Some magnetic readers have lip seals on the reader (I have them on my EL700) and I cannot see swarf contaminating them. As far as pricing, I would get an Easson DRO with magnetic scales of any length, you can get the package cheaper direct from the UK can through AliExpress. I would review this thread below:

Lathe owners with DRO’s

Big fan of DROPros products ;)

www.hobby-machinist.com

 

[darkzero]

I've had glass scales on both my lathe & mill for over 10 yrs now, never had a problem with them & never had to clean them yet. I don't use flood coolant but I do spray on coolant manually with a spray bottle at times. As long as the scales can be installed in a desirable manner they should be fine, ie read head slot facing down not directly exposed to contamination. I also run guards on my glass scales which do get quite filthy.

Mag scales were very expensive when I bought my DROs. My glass scales are Chinese too, Sino & Easson which are more popular Chinese brands if that means anything. Mag scales have came down in price since then but if I were buying today, unless I needed the advantages of mag scales I probably would just buy glass again.

Mag scales are geat cause you can easily cut them to length yourself. Well techincally you can cut glass scales too but it's not recommended & much more risky. They have a smaller form factor & they say they aren't affected by contaminates. I'm still skeptical about the latter though as I've heard of people have having problems & needed to clean them.

I had no issues with sizing using off the shelf glass scale lengths for my machines. I used a slim scale for my cross slide also. For the bed & my mill I used standard size scales. I have no actual personal experience with mag scales though.

 

[hman]

FYI - Another alternative is inductive-type scales. The scale and read head are totally enclosed, so they're completely coolant and chip proof. The scale is a hollow cylinder containing a stack of precision ball bearings. The disadvantages of these scales are their high cost and the longer-than-usual size of the read head.
Sperosyn and Microsyn are two brand names, sold by Newall

Sensata | Newall | Sensata Technologies

www.newall.com

 

[Larry$]

I've got Easson glass scales on both lathe & mill. No problems, but I don't flood.

 

[Suzuki4evr]

Hi guys.
I will be purchasing a Ditron D60-2V with magnetic scales for the lathe. I have a question though. Can you install a mag scale upside down if needed?

 

[mksj]

They can be mounted in any position, doesn't matter. Also very forgiving of alignment, but as mentioned I still recommend a chip cover.

 

[Suzuki4evr]

I will make a plan for cover,but if it is swarf and coolen proof, why do you need one? O and the price was $393 on Aliba express incl shipping to South Africa