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View Full Version : a word of advice and a request for more advice...



psomero
08-24-2005, 05:06 PM
paul's lesson of the day:

if you are using a tool, never ask yourself, "i wonder how bad someone can get injured using this tool." you will soon find out.

http://home.pacbell.net/psomero/burrwhip.jpg

i didn't think something as benign looking as a burr whip could make me bleed so friggin' bad. it wasn't deep, but it was about 3/16" wide...

and on a nicer note, i found these tucked away at the bottom of a box at work yesterday:

http://home.pacbell.net/psomero/freebies.jpg

i almost cried when i found them, both in about a quarter inch of grease, and i let my boss know how sad he had made me. he instantly changed my spirits by telling me they were "too worn" to use for contract work any more and told me to take them home or toss them in the garbage. you all know damn well which choice i made.

one's a brown and sharpe and the other's a mitutoyo. they both have wear on the skinny parts of the jaws and the ID measuring jaws, but they slide smoother than the $17 chinese made mcmaster-carr special i've been using since day one. is there anything i should do to clean them up better or perhaps make them more usable?

Alistair Hosie
08-24-2005, 05:54 PM
Well done paul; some guys are born lucky. I am one of them http://bbs.homeshopmachinist.net//biggrin.gif Alistair

rockrat
08-24-2005, 06:49 PM
I have seen some of the worse cuts come from burr removing tools. Two come to mind.

First was a whip type that a fellow was using on a sheet steel part. It hit a gouge and skipped off. Off of the metal and into his thumb that is. I had to take him to the hospital for stitches.

The second was a burr tool that has two carbide inserts on either side. You can put the edge to be burred between them and pull. It makes a nice smooth edge. But this fellow was trying to burr the end of a 4" dia 0.035 wall tube. He was pulling the part and holding the tool still (relatively). The part skipped and he pulled it across the back of his hand. Blood city! Poor fella was shaking like a dog s$%tn razor blades when I got back with the surgical gloves and gauze.

Count your self lucky indeed. Sometimes little accidents like that remind us of how bad things can get around machine tools. A bit of edumacation. It might have made you safer the next time you went to run a machine, only because it was fresh in your mind.

And keep finding treasure at work!
rock-

JRouche
08-24-2005, 08:47 PM
<font face="Verdana, Arial" size="2">Originally posted by Alistair Hosie:
some guys are born lucky. Alistair</font>

I'm just lucky to be born http://bbs.homeshopmachinist.net//tongue.gif

Ok Mr. Burr whip make blood drip, drip. What is a burr whip? JRouche

CCWKen
08-24-2005, 09:47 PM
You sure you didn't just drip some strawberry jelly out of your sandwich. The pic's too blurry to really tell. Or it might be a mosquito bite, I don't know.

psomero
08-24-2005, 10:09 PM
<font face="Verdana, Arial" size="2">Originally posted by CCWKen:
You sure you didn't just drip some strawberry jelly out of your sandwich. The pic's too blurry to really tell. Or it might be a mosquito bite, I don't know.</font>

yeah, the camera i use is horrible. my dad bought it based on ease of "point and shoot"-ability, not quality of picture...

vinito
08-24-2005, 10:12 PM
That reminds me of my first injury as a machinist story.

Somebody at the shop had made a thread ring gage to use on the shafts. Six inch diameter thread, so it was a pretty big ring. The ring had a bolt hole pattern that cut through the OD leaving six C-shaped gaps about a 1/2" wide. When they handed it to me, the gaps had never been deburred, and it was ominous just to look at. Being a rookie, I didn't know whether they wanted me to go filing on their gage or not, so I didn't.

Cut to a couple hours later and me holding my hand to keep the juice in. The thing bit me despite my fear of it. Pretty good too.

Then they had the lack of sense to tell me "Well we've been using it for the past year and nobody else has ever had a problem". When they told me that I was furious. "So you are telling me that over A WHOLE FREAKING YEAR nobody could figure out how to put a brain cell and a little elbow grease together for five minutes and deburr their damned thread gage?"

Of course these days I have more confidence than common sense, so I'd file on anybody's gage if it looked like that one. I guess I learnt sumthin'.

Deburr your work. Deburr theirs too I guess.

[This message has been edited by vinito (edited 08-24-2005).]

madman
08-25-2005, 10:52 AM
In regards to your verniers. Clean them open all the way blow compressed air down the rack towards the fixed end only. Never blow anything into the clock work. Take a 0ne inch gauge block and close the vernier jaws on the block note deviations. When you use your vernier use the same area of it that you calibrated with the one inch block. They wear quite a bit but with a gauge block as a standard they can be used almost indefinately.

BillB
08-26-2005, 09:34 AM
To add to madman's advice:

Wear often results in a dip in the jaws which prevents gage block contact. If so, use a fine stone to get the jaws flat & parallel again. Hold them up to a light & use magnification to check. Unless you are a masochist, devote one pair to ID use and the other to OD use (maybe even cut off the other jaws), 'cause it would take forever to get both sets of jaws on the same caliper aligned & reading the same error.

Re-trueing can be delayed a bit by marking the "sweet spot" on the jaws with Sharpie marker or layout dye.

Used to use the plastic/fiberglass/whatever calipers on polished silver to avoid scratches, we did this all the time with them.

BillB

[This message has been edited by BillB (edited 08-26-2005).]

Paul Alciatore
08-26-2005, 10:53 AM
I don't think I would use compressed air at all. It has a way of blowing things every which way, not just where you are aimimg. I would clean the racks with a NEW toothbrush and some solvent. Not a used one as toothpaste is abrasive.

Then examine the racks under magnification to see if any small debris is still in the teeth. I did this with every import dial based device I have purchased and it has yielded good results. You may have to use a fine wire or pick to clean out some stubborn chips.

I would measure the corner of a gauge block or a ground block with parallel faces at various places along the jaws to see if there is any uneven wear. There may be wear at the edges while the faces of the jaws are OK. Look for any difference in the readings.

Check with several gauge blocks that are in a 1/20" range to see if any differences show up. 1/20" usually equalls one turn of the gear that rides against the rack and it is the most easily damaged. Here you are looking for accurate readings across the range so gauge blocks are needed.

I wouldn't open the dial mechanism itself. If it is working leave it sealed.

Paul A.

ibewgypsie
08-26-2005, 12:12 PM
WHOOO HOOO&gt;. I got the other press to working, tied the hydraulics into the One supply from the other.. no leaks.. yet.. I used a 1/2 coupling I was afraid would explode *china made.

I am building a hole punch for it..

Back On topic? I got up into a cabinet years ago, seeing these poly lines I didn't pay them much attention. One of the poly lines came out of it's snap fitting, I got whelps worse than momma ever gave me with a hickory.. Bloody striped..

AIR is dangerous, as is contained energy in the objects it moves.

Back to the shop, hooking up the microsecond pc timer to the spotwelder. whoo hoo.. be done here in a bit too I done checked the software.. same pedal makes all three objects work according to software.. Manual only on the 50ton press tho.

See ya later alligator..