I am I being too picky?

[DaveL]

I looked at Tonys thread about upgrading his morticer and made a note to do the same sort of thing for mine. Well I got round to buying the cross viceyesterday from Machine Mart, as they have opened a branch in Colchester, only 15 miles down the road.

I have spent today modifying the vice and morticer. I drilled and tapped the holes to allow the top slide handle to face the front. I made a spacer block from some very hard wood that came in a load of fire wood. 8) I removed the metal jaws and made some nice Ash ones. I drilled the table on the morticer to allow the vice to be bolted down. I even drilled the bench to bolt down the whole thing as I was nervous of tipping it on my toes. :shock:

I came to the last part of the set up, checking that the slide movement was parrel to the chisel. It was a little out, I slacked the bolts and nudged the vice. I recheck it, it was a little out :evil: . At this point I think I lost touch with reality, I took the vice off the table and filed the holes into slots. :shock: I put the vice back. I check the alinement, it was still out. :x

I took a step back and thought about what I was doing, something was not right here and I should of seen it. On checking I have found that over the 5" length of the jaw the vice is 75 thou out of line with the slide. I am I being too picky? Should I try to take to back or should I just plane the ash to get it back in line?

 

[Midnight]

Typically, machine shop drawings I've had occasion to use over the past 20 years have had an acceptable tolerence of plus/minus 3 thou for any dimension... the machinists at work accept this as easily doable.. no biggie.. and they're not using state of the art machines, most of them dating back to the war..
I reckon 75 thou's takin the biscuit Dave; the manufacturer has a QA prob that's gonna be glossed over if you rectify the error yourself...

 

[Bean]

Dave 75 Thou over 5" is a lot for a cross slide or for any sort of machining as Midnight says. I would take it back. I dont think you are being picky

Bean

 

[Anonymous]

Dave

Hard to say. The vice is very cheap and not of the quality Midnight mentions; such as that found on £300,000 machine tools. I haven't checked mine and it has been fine when used to cut mortices. However, 75 thou sounds like a lot and I would have noticed that much on mine.

Can you adjust the missalignment out? The slides are adjustable with allen screws and lock nuts

If not, then take it back!!

 

[Midnight]

The vice is very cheap and not of the quality Midnight mentions; such as that found on £300,000 machine tools.

huh..??? quality...??? you ummmm.... realise I was talking about the Boer war... right..??? If I remember right, we've a pair that were used in munitions production during WW2.. fine auld machines but showing their age thesedays...

I'm guessing that the sloppy tolerences are a sad reflection on the quality of patternmakers this manufacturer's using, given that a casting's only as good as its mould...