Chinese tools

[Larry Schweitzer]

I just got 3 new Chinese tools for my metal working area. All came from Shars. The 18x24x3" granite surface plate and stand seem OK, I have no way of measuring the accuracy. I went about turning the Spin Inexer into something better. The bore seems relatively decent in terms of clearances to the spindle  and base but the faces are not perpendicular to the bore so not useful for setting up references. I turned a 31/32 steel bar to use as reference so I could mill the cast edges to the bore. That will allow me to mount the indexer in the mill vice for quick setup for short parts. For longer parts I'll be able to use a test indicator to true the indexer to the table travel and make a tail stock support (next project.) There was a lot of grinding dust in every nook and cranny. Cleaned that out. I haven't gotten a good start on the tool grinder yet. Some of the moving parts seem sticky, more grinding dust and burs? I would like to buy US made things for this hobby but could not afford to be in this hobby doing that. A quality US indexer $800 VS Chinese $55 and some time to make it good enough for hobby use. The tool grinder Chinese knock off of the $8000+ Deckel German one  seems OK for $850 after some cleanup. Again this is a hobby not a business use. Any thoughts? 

 

[lew]

Although I prefer to buy products made in the USA, some things I just couldn't afford. My Taiwanese tools do the job just fine- for me. 

[Grandpadave52]

I'm like Lew. I prefer US made products when I can, my budget allows or what will be my level of use. Like you, some items need tweaked here/there but give me the results I need or expect for far less $$'s.

 

In your specific case(s) if these tools perform to your satisfaction for the hobby work you're doing, offer an acceptable level of repeatability, and provide the outcome (finished product) you need, then that's what matters. Unless you need tolerances in microns, I'd said you're OK IMHO.

 

As for the flatness of the surface plate, without a Verification Certificate or recent certification, yours is as accurate as any. Unless you've been holding out and not showing us your hidden CMM room  or plan on sending out to a third party inspection/gage lab periodically for certification no guarantee a much more expensive one is any more accurate (flat).

 

Your knowledge and experience comes into play here too...knowing the differences and how/where/when to compensate puts you far ahead of most.

Edited February 27, 2018 by Grandpadave52

[Larry Schweitzer]

Grandpadave, The surface plate came with the usual Chinese type certification and a "Report" showing the deviations and the standard met. It actually has the same serial # that is on the plate. But did they actually test it or is this just a copy of the last one they did test and have been photo copying it for the last 500 units made? My tolerances are "As good as I'm capable" but that isn't in microns!  I finished the Spin Indexer tweaks and made a spanner wrench for the retaining nut. A few test cuts to see how good it was at indexing all the way around and coming back to the first notch. Actually works very nicely. 

[Grandpadave52]

20 minutes ago, Larry Schweitzer said:

The surface plate came with the usual Chinese type certification and a "Report" showing the deviations and the standard met.

As you know I'm sure, really means nothing...if the Certificate isn't traceable back to NIST it doesn't really matter unless you're doing work that would require such. I know you understand, but the point I was attempting to make, even if you had bought a used surface plate off eBay or even local, the odds of it being any more accurate than what you bought are minimal unless it had been certified w/i the past 3 mo. Technically, after a plate has been shipped or moved it should be rechecked. All good if you need that level of accuracy...of course it doesn't come without cost either as you know.

 

I've got a couple H-F digital calipers...they seem to be accurate and repeatable at least from 0-2" when checked against my much more expensive Starretts, 0-1", 0-2" micrometer style mics...of course they haven't been re-certified for ??? other than me checking calibration against the 1.000" & 2.000" standards I have and they haven't been checked for ???.  Anyways, they all work for me for what I do and I can't see any issues from the middle of the road.

[Larry Schweitzer]

So today I decided to make a trial part using the Spin Indexer. Turned an aluminum knob with a 15/16" sub to hold in the collet. Planned to use a ball end mill to make a scalloped edge. I had used the same collet in making the blank as I was to use on the indexer. A good fit. I mounted the part and tightened the collet as tight as it would go given the system on the indexer. It didn't hold. Some investigating revealed that the draw tube that pulls the collet closed was too long and hit the end of its travel before the collet fully closed. Took the handle off the draw tube so I could turn 1/8" off on the lathe. Turns out there is no solid attachment between the handle and the tube, 3 little set screws. No flats or dimples. The result is the handle simply slides around the tube when the torque is way short of what is required to close a 5C collet. I got the knob made but could only take .015" depth of cut per pass. It took 5 passes on each of the 9 recess, 45 passes! Got to fix that! I decided to drill small pockets for each of the set screws to seat in. Tried it, works. So the spin indexer KIT is finally finished, I hope.