DRO for Harbor Freight 47158 based on Harbor Freight 93293 Calipers

[Temtu]

Originally Posted by darkith Nod, your original question was related to "mount the caliplers to the axes and make the mechanical prototype", so I thought that's where the hangup was. Milling a precise fit for the LCD, PCB, and zebra strip could also be challenging. My point was to start on the harder parts of the problem to ensure that they're solvable before progressing to the simpler parts. As it stands now, I'd try crafting a simple 1 LCD temporary holder for the LCD, PCB, and zebra strip. Then try connecting over very short wires for testing. Once that's working, I'd build the P->S->P circuit and test it over short wires. If that works I'd test it over long wires. If that all works, you're at the point of looking for a final mounting solution for your LCDs and calipers. Anyways, I am interested to see how you make out. If I ever get around to building my cheap DRO using serial LCDs instead of more expensive LEDs, I'll share it. I'm still debating if I'll build it though, as I might just go straight to CNC and skip DRO. D. PS. I have one of those plastic calipers....got it at the canadian equivalent of HF. I'll point out that the accuracy printed on the back is only .01" (HF's listing is wrong), and even if you trust that, it's not very accurate for a lot of work. I bought mine and pretty much gave up on it...the cheap metal calipers for $15 are a much better deal IMHO.

Team

"My point (also) was to start on the harder parts of the problem to ensure that they're solvable before progressing to the simpler parts."

To me, electrical parts are easy.. Especially in the world of Spice, Tina, LTSpice and similar design & simulation tools. Apperantly (to me) it is more difficult to find some help with mechanics )

Anyway, as Goethe says, "patience...". I will wait until somebody rise to challenge to adress the mechanical issues.. Then I will be gladly making the electrical parts work, long before the mechanical parts are ready..

M

PS: You are right, these caliperers has 10 mil precisson; not 1 mil, however, backlash/stability in the micro-mill is not the best either ))

PPS: Anybody out there to give a serious try to mechanical parts ?

[Donkey Hotey]

I just did a search on eBay for DRO. There are a number of resellers that carry ready-made DRO kits for each axis that are based on the same Harbor Freight electronic modules (vertical and horizontal). It looks like $45/axis would get you a DRO (with displays in three different places).

So the point of your exercise is to remotely mount the displays? Why not stick to off the shelf parts so you can throw them away when they go bad?

[Temtu]

I did immediately check Ebay and could not find something which can fit to Harbor Freight 47158.

Please share with me the item number you see in Ebay.

Please also observe that 47158 is micro-mill.. It is not a Bridgeport ))

[maxboostbusa]

I have 3 of digital scales off of ebay on my mini mill. 2 was a 12 inch unit for a bridgeport which doesnt matter what its for it will fit anything you want to bolt it to and the other was 8 inch digital calipers I cut the jaws off of tapped the back for mounting plate and machined some hdpe for scale mounting brackets. I got mine from a seller called 800watt. great prices and I didnt have any trouble with shipping or anything. Just do a search for digital scale on ebay they come in horizontal and vertical display setups from 4 to 40 inches Just my 2 pennys.

[Donkey Hotey]

12" vertical: 280174305557
6" vertical: 200176198930

12" horizontal: 280176844364
8" horizontal: 270189930164
6" horizontal: 280177142056

[Temtu]

Originally Posted by Donkey Hotey 12" vertical: 280174305557 6" vertical: 200176198930 12" horizontal: 280176844364 8" horizontal: 270189930164 6" horizontal: 280177142056

Many thanks for your time & efforts.. Donkey Hotey.. I will try to see what I can do with this large DRO's..

[Donkey Hotey]

Wow! I just looked up the model you're putting this on. That thing IS small!

x-9'', y-4'', z-8-1/2''

Don't spend too much money on it. Machine tools beget more machine tools: just about the time you get it outfitted the way you want it, you'll want to do something it can't do and you'll start the path to bigger machinery.

I've been on this journey for 8 years. I now have more than I dreamed possible when I started.

[ZipSnipe]

Temtu, awhile back when I first got the machining cnc bug, I too thought wow I,ll just make a dro out of calipers. Well I ended up getting a z-axis scale from Shay's (Harbor Freight same deal) anyway it turned out to be very unreliable. At least +-.010 and then the slightest bump made it go crazy. So I opted out of making a dro. After using the milling(Bridgeport)machine at work with Annihiem DRO, I wouldn't use anything else other than a good DRO, get one off E-Bay!! DRO's are for accuracy and if it's a couple thou out then it kinda defeats the purpose! Good Luck.....

[acidjazz]

Originally Posted by Temtu Everything which is not tested, does not work. So in one hand you are right that P->S and S->P it might be challenging... However, is chicken or egg first ? To me, unless I find somebody with precission milling experinece to mill the Triple or Dual LCD housing with thin Zebra holder, this low cost idea is just an idea. I learn every day and have been part of teams ( or alone) shipped electronic products for many years, for many hundered millions... This low cost idea could be another learning experience )) PS: Harbor freight 93293 calipers are reinforced plastic so grounding is not an issue.

hi Temptu, I have a new mill and I would be willing to mill those calipers for ya if you might help me someday fix a redout for my machine, thanks HOmer