Another Chinese Magnetic Scales Thread

ycroosh

ycroosh

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Ho Folks,
So, I have a question...
I get a few emails per week from people asking where to buy decent magnetic scales. DRO Pros sell EMS/Electronica scales that are very good "budget" scales, but they are not super excited about selling them individually. I've had heck of a time ordering a scale (took a week, and 5 phone calls), and I've heard from many customers who had similar or worse experience (although, for fairness, support from DRO Pros when buying a full kit is excellent... It's just that selling scales is not their business model).

My plan B was to resell EMS scales. I don't know how to say it kindly, but I have NEVER IN MY LIFE dealt with a company that was so unwilling to take 10K$ + from me. I've called them (in India), emailed, filled out a "inquiry" form, then called, and called. Two weeks ago I got a hold of someone in their "export" department. His first response was "this will be very expensive to ship to the US". When I kept asking for a quote, he got my info, and for the last 1.5 weeks is responding every 2-3 days with "we are still working with the shipping company to get a quotation". Long story short - f...k EMS. I am not comfortable dealing with this sort of a company.

My plan C just emerged earlier this week - I randomly re-tested two Ditron EMR-2000 read heads (full size 1um scale). With Ditron's tape it was "passable". I.e. I got close to +/- 20um of error on both heads over 18". Then just for giggles I tested the same heads with RLS tape, and got +/- 6.7 um on average. This is VERY respectable. This is actually better than EMS scale with EMS tape. The obvious catch is that RLS tape is $140 USD per meter, whereas standard Chinese tape is about $15 per meter. So I emailed the person I know at Ditron and asked if they know a source of higher quality tape. Well, they do - Ditron. Apparently, if I pay extra $20 per head and about $30 extra per meter of tape, I can get their "high precision" tape with reference marks.
They sent me a few test reports, and two out of three looked very good, with under +/-10um or error over 1m. The third had +/-16um. After a bit of back and forth, they offered to take any scales that fail my testing back (I would need to pay shipping back to China though).

I did some math (well, a lots of math), and even if I factor in my labor to test every scale, the cost of shipping bad ones back, and some markup, I can still sell those scales for less what EMS go for (or even a bit lower). Since they will be hand-picked, they will likely have better specs than EMS scales. Plus, since I am buying stuff a-la-carte, I can sell it that way. I.e. for people who don't need the aluminum extrusion, I can sell the read head and the table in bulk, etc.
So, back to my question (for those who ran a business before): is it a crazy idea to buy Chinese scales, hand-select good ones, and resell them? How would one figure out what a reasonable (and fair) price is?

Regards
Yuriy
 
You really want to test every scale that comes through and then deal with the rejects? My experience is shipping from China is cheap, the return trip is expensive and may be quite delayed, so probably more than the cost of the tape you are returning. Then you need to deal with inventory and shipping, just not enough margin there for the effort. What I usually see is many people end up buying the cheapest DRO/scales they can find, most will not even care about the tape error let alone have 18" of travel on mini this and mini that. Alternative is to just setup a pass through link to Ditron/AliExpress with the higher resolution specifications outlined, and then they can directly order "the high precision model" and see if Ditron can add it to the pull down menu or have it tied to your link.
www.ditron-dro.com

Magnetic DRO Scales | Ditron

Ditron is China's leading manufacturer of DRO system,magnetic dro scales ,we can provide you with high quality magnetic scales.
www.ditron-dro.com www.ditron-dro.com

Ditron's price for an 18" 1um magnetic scale is around $176, add another $30-50 to that for high precision and you are priced out of the market, and that is with you having to deal with all the headaches and probably a loss revenue wise. It is less expensive to order it the Machine DRO, 1 micron head is an extra $20, you deduct VAT and shipping was not too expensive in the past. If you want high linear resolution, glass scales are much cheaper and for the most part pretty decent. I know at least a dozen people that have ordered complete DRO kits with magnetic scales for Machine DRO, not aware of any of them complaining about the scale accuracies (both 1 and 5um).
www.machine-dro.co.uk

M-DRO EHC Series Compact Head with 465mm (18 5/16 inch) Reading Length Magnetic Tape Encoder

The M-DRO EHC Series compact linear magnetic encoder with 465mm (18 5/16 inch) reading length tape. 5 Micron (0.005mm) resolution. Featuring the DRO-MG-EH-05C Compact reading head, which offers a smaller reading head size compared with our standard EH series head. The dimensions of the compact...
www.machine-dro.co.uk www.machine-dro.co.uk

Your review of the different scales on your website is very helpful, would be a real PTA to have a high expense item when there is little to no profit margin. People can choose based on the information you have provided. Unless you plan to go into full blown production and have more of a margin, I just can't see trying to add this to your pile of thing to do.... Just an opinion.

Adding a decent electronic edge finder that works with your DRO kit, may be worthwhile and/ot a link to those that you recommend.
 
Sorry slightly off topic but how does this sort of precision compare to, say, ditron optical scales? The generic cheap glass scales that I'm using.
 
I run a completely different kind of business. But i do think some of my experience is relevant. If i were in this situation i would completely understand your approach to getting a quality product out there at a price that seems good - this is who i am too. But the profit would need to be there. It took me a long time to get to where i charge profit at a rate that seems appropriate. I just had a hard time bringing myself to do it, wanting to be 'fair' to customers, and being a crankee yankee i have some inherent value to dollar that doesn't line up i with my customers. For them price is hardly the concern it is all about timelines and quality, cost is what it is to get those first two criteria met. I have literally lost jobs for not charging enough. by a lot.

For your specific situation if you can make a decent profit one each scale even after testing and returns to supplier perhaps it is worth it. Do you want to spend all your time testing and mailing? will it not actually be that much time? will it be way more? probably impossible to know until you are through a first batch. Why is the supplier reluctant to meet your specs? my experience has taught me that gut feelings about suppliers are shockingly accurate. ive been screwed by people who i could talk to in perfect native American that seemed fine and assured me in writing they could provide what was needed but felt 'off' more than once. custom parts from nonamechinaebayspecial come through faster than promised and perfect.

Can you figure out what other outfits are getting for profit margins? i have had a heck of a time figuring this out myself, or even the competitions 'shop rate'. Mechanics and plumbers have to tell you their hourly rate, apparently woodshops dont. You may be able to have a smaller pofit multiplier if it is just you, and limited inventory, as you built to better margins and larger volume. Or you may not. Finding where it works for you is key i think. I know you have said youd like to take this on full time, and the profit would need to be there. Profit from volume or higher markups are the ways to get there. The subscription portion of TouchDRO can help there too im sure - not my world. But you still need to be profitable on each part. Selling scales at cost or loss does not seem viable to me. Intro software at a loss (or free) to get people hooked seems more reasonable if you want to do that.

A few random thoughts:
-Finance a first trial batch of personally garanteed scales as you describe with pre-sales. ill buy a complete kit from you today. i bet there are others on here that will too.
-As much as i dislike the influencer crap - know one? know someone who does know one? get them a full kit and babysit them through it so they put it front and center on some channel that will buy your product. Touch DRO does seem built for that market.
-another member here and i spoke about a tool im working on and his thoughts on kickstarter etc. were insightful. essentially he saw i was comitted to getting my tool to production ready prototype with pricing. essentially a micro-run to see how it would work. i thought i would try and sell them at cost to others i know who could test them out. The big point i took away from his perspective on an online crowdfund simulaneously was that i would have a much better guage of interest outside my small sphere, and i could potentially increase sales at little to no rist to actually become profitable. Again, TouchDRO seems made for this. Price the full scale/touchDRO/software/1yr subscription bundle and put it out there.
-i have not used your software or system (but will soon!). i am not a machinist. But how the heck have bigger shops/production facilities not seen the value in your software systems for their production! it seems obvious to me. like almost as good as jumping from a WWII bridgeport to CNC. there has to be a way to get to that market meaninfully. I pay $$thousands a year for CAD programs and im a one man shop! find ten of me that need your software/hardware and you a almost to full time.
 
My boss told me once that 4 to 5 times your cost is what you should charge to make a decent profit. Maybe less would work for you.
If you can sell it for 2/3 your competition's price that might be a starting point. Go up or down from there. Perhaps hire a student or retired person to help do the testing and handling on a part-time trial basis, if the volume warrants it.

AFAIK the main advantage of mag scales over glass is the small footprint, not the accuracy. Is that true?
 
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Some thoughts [ back in the 90's I was involved in setting up and operating a company that sold semi-unique industrial materials (cushion materials, custom sizes, and some differentiation from similar companies' offerings)]:
  • Tying up your money in stock that needs to be returned could really mess with your cashflow.
  • Inventory is expensive and doesn't generate profit [although having what people want in stock does generate sales: when Precision Matthews machines are recommended, many potential buyers are put off by long lead times or accessories that are frequently out of stock]
  • No matter how good your initial relationship and agreements are with your supplier(s), there will be issues that come up which will take significant time to work through (and explain to your customers)
  • Although you would be offering better quality products and customer support at a better price, the "Big Boys" will do whatever they can to suppress you [I know, a very negative outlook, but unfortunately the facts of business]
I know you have dug into this previously, and are just as concerned as we are that this venture could be the one that burns you out.


Best regards and good luck whatever you decide, Charlie
 
Thank you for your feedback/suggestion, gentlemen. Very thoughtful, and much appreciated.
A few thoughts I have (so far):
1. I don't want to be testing scales, but I have "robots" for this, and a wife who can run them. My interferometer stand is automated. It takes about 2-3 minutes of human time to mount the scale, and then 20-30 minutes of run time. It can run 3 scales at once. For now this is more than good enough. If I get to a point where I'm selling more than 24 scales per day, I will be able to figure something out.

2. I can't get a profit margin on scales that is the same as what I get on my adapter. Definitely not 4-5x my cost :) I can get respectable profit margin (after accounting for the extra labor, etc.) for this to make sense. The main motivation is not the profit I would make on selling scales, but the profit I'm loosing on adapter sales due to buyer friction. I hear these sort of things from potential customers a few times per week now: https://www.hobby-machinist.com/thr...r-experience-with-dropros.115043/post-1176662.
Counterintuitively, this would reduce my work load. My wife can handle 100% of this; I still have to deal with technical questions, scale recommendations, etc. So far it's been the case that the more turn-key I make TouchDRO, the less work I have.

3. DROPros vs. PM is 100% apples-to-apples - they sell the same scales. Well, actually, Magna s2 is a more expensive scale than MagnaSlim (by about $20 in bulk pricing)/ EMS scales are better than default Chinese magnetic scales, especially 5um vs. 5um, since EMS uses 2mm pole-to-pole tape, and Chinese scales use 5mm tape. 1um EMR-2000 "high precision" head vs. Electronica Magna s2 might actually be a wash. Obviously I haven't tested one yet, so I'm speculating, but the reports I got from Ditron look better than the "certificate" I got from EMS. So far it looks like my price for 3 scales will be less than the lower end MagXact kit, but display with 3 scales will be more expensive (as expected, and justifiable so).

After sleeping on it, I think the most logical step for me is to order a small batch (50-ish units) and see how the testing looks, and how they sell. If the scales are better than the two I tested last week, I am comfortable selling them and offering my warranty. If they are not, I can sell them on eBay, recoup my money and time, and move on with my life.



As a side note, a confusing (and somewhat frustrating) thing regarding TouchDRO vs. other DROs is that many machinists have a weird attitude towards DROs.
Most people understand and accept that a PM-xxxVT machines cost more because they are built to higher standard, Precision Matthews does extra QA on them, and offers service above and beyond other vendors. Some people can justify this cost, some can't. Then there is Grizzly. It's a step down, but is a bit less expensive. Then there is (or was) Harbor Freight/Princess Auto, etc. It's cheap because they use lower grade parts and skip any sort of QA. Then there is Vevor stuff that you can buy on Amazon, eBya, etc. that sells the lowest end QA reject crap you can find for REALLY cheap. I haven't seen anyone go "well, PM priced themselves out of the market... unless they match Vevor ...". On the flip side, I've seen dozens of times someone buy a 5K$ PM VT machine, and then get "a DRO" for $200 total from AliExpress without any second thought about the quality/value/price they get with that unit.

I can't compete with DROs coming from China or India, especially the ones that "fell of the truck", come with no QA, support, or warranty, and are based on designs that stopped being cutting edge when Clintons was in the oval office.

I'm sure I'm biased and my be completely wrong, but IMHO at this point TouchDRO is the most (if not the most) capable DRO on the market. I haven't seen anything that can do 3/4 of what TouchDRO can do. The hardware I sell is on par (and in some regards better) than Acu-Rite. I know it's bold statement, but I'm paying trough the nose for IPC-A-610 Class III compliance (this is "aerospace and medical" level stuff; industrial and automotive is Class II, Consumer is Class I or below), name-brand parts, ISO9000 assembly, and then fully test each unit. I know for a fact that TDA-4xx adapter is faster, more capable, and more flexible than anything you can get from Acu-Rite, Newall, etc. by a long shot. (I'm not trying to diss these companies. They make top-notch stuff, offer very good support, warranty etc.)

I get that many, or may be even most, machinists don't need this, but I'm sure there are many that do. Somehow I need to figure out which things add value, and which things needlessly inflate price and provide no value.
 
Well, I’m interested to see what you come up with for packages and pricing as it’s going to be 4 or 5 months before I can use my mill again so I’m not in a rush to buy a DRO kit.

I do wish it was possible to find a tablet that didn’t have a battery in it at all.
 
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