More dial gauge observations

reible · Post by **reible** » Tue Sep 25, 2007 12:09 pm

Don't worry I will not be going on much longer with these sorts of posts since I have a project I plan to start this afternoon.

I went to check the alignment of my rip fence (520 system) today using the dial set-up gauge. It was just fine but no I didn't stop there.... Knowing that each and every time you move the fence to a new location and reclamp it things could change. Where first took the readings I was within .002" with the back of the fence towards the right. After trying several locations the numbers changed, always showing the fence to the right but in some spots it was off by .005".

I also tried to do a run on each side of the fence without moving the fence, that is, one from the left miter slot then one from the right... however I couldn't get that to happen because of the gauge and how it is put together. I'm going to dig out my other gauge and see if that can be fitted to the set-up as it has a short "neck" and just might work??

Now I got to the interesting part of the testing. I have a certain way I put the fence on and clamp it but sometimes I do it differenct ways because of how I have the setup of the shopsmith. What I now did was try different clamping methods like plopping it down and clamping, sliding and clamping, sliding the other way and clamping and well just about anyway I could think of and then checked it. One thing stayed the same, it was always with the back of the fence to the right but the amount was varried from the .002/.005 numbers to as high as .015" and .012/.013 was a common high number, and the bulk of them came in at .010 or below.

What this seems to show is that the clamping is a bit more critical then I would have guessed. And it was interesting that during all this never once did the fence show up off to the left.

I'd like to see some other data from other users about this, and from some 510 users. I know on my 510 it seemed harder to get it clamped just right right which could be just the condition of the used one I got???

Ed

charlese · Post by **charlese** » Tue Sep 25, 2007 10:11 pm

reible wrote: I also tried to do a run on each side of the fence without moving the fence, that is, one from the left miter slot then one from the right... however I couldn't get that to happen ...

Now I got to the interesting part of the testing....(sliding and clamping)... One thing stayed the same, it was always with the back of the fence to the right but the amount was varried from the .002/.005 numbers to as high as .015" and .012/.013 was a common high number, and the bulk of them came in at .010 or below.

What this seems to show is that the clamping is a bit more critical then I would have guessed. And it was interesting that during all this never once did the fence show up off to the left.

I'd like to see some other data from other users about this, and from some 510 users. I know on my 510 it seemed harder to get it clamped just right right which could be just the condition of the used one I got???

Ed

From Idaho Falls, ID

Just looked up the data I posted in "What to do on a hot day" Thread. Looks like your rip fence is pretty darn true and stable. Yes, your 520 is "looking' good".

I was able to run the dial indicator along the full length of my 510 fence and that is how I found that my fence is not perfectly straight. There is a pretty uniform bend in it - no kinks - just a bend. This probably came from abuse.

Finally this is what I wanted to mention - - the rear clamp on my 510 fence always moved the fence to the left about .012".

My fence was off about .02" to the left. I'd rather have it off to the right as I usually saw to the right of the blade. I tried to adjust the fence by pushing a little first to the right and then to the left while the front clamp was tight and rear clamp was open. (Really can't recommend this operation) This resulted in a little correction. Next thing to do is to twist the rear clamp a little to take out the clamping error mentioned above (.012).

reible · Post by **reible** » Wed Sep 26, 2007 12:37 am

Hey glad you are keeping to your idea of posting where you are at. That's still some miles from your new home... but somewhere near where you use to live, right??

I was mostly interested in do some general testing today and I'm not sure I would want to use the gauge to set anything. The slop in the miter bar on the right miter slot is .006. I might just make some changes so I can use the miter gauge for doing this. I was also thinking of how I got several results just by moving the fence a 1/4" and relocking. Is the .002 right or is the .005 or some where between the "real" number?? In this respect the gauge just makes me wonder... without it I wouldn't even think of it.

The other interesting thing I noted was how much difference I could generate just by how I put the fence on and clamped it. I can do very well when I can be right in front of the machine to do the locking but when I have the front extensions on I have to work to the side and this can result in less then perfect results. I guess I learned I'll have to work harder at the locking process.

I'm now thinking of a way to measure how close the fence is to straight when it is on a floating table or feet away on a extension table.... or maybe I don't want to know.

Ed

charlese · Post by **charlese** » Wed Sep 26, 2007 11:20 pm

From Fillmore, UT

Yes, We were up in Missoula, MT for my wife's 50th graduation from nurse's school.

I was surprised to read (both your's and Dusty's) the amount of slop of the guage in the miter slot. As I remember I only had around .001 to .002. This may be off - but I'll check on the weekend.

Don't let that little guage drive you nuts! But have to agree it is fun to play with. Amazing how close we got the set ups to perfect. These set ups have always been good enough for past work - I think they also will be in the future. Doesn't hurt to test though.

Tomorrow, Vegas.

charlese · Post by **charlese** » Sun Sep 30, 2007 5:34 pm

Guess I'm pretty lucky!:D My miter guage slop inside of both miter slots is +0.01 and -0.01. That gives me only 0.02" side movement in both slots. To me this is pretty darn close.

reible · Post by **reible** » Sun Sep 30, 2007 11:58 pm

charlese wrote:Guess I'm pretty lucky!:D My miter guage slop inside of both miter slots is +0.01 and -0.01. That gives me only 0.02" side movement in both slots. To me this is pretty darn close.

Interesting numbers... On the other site someone had mentioned a sloppy fitting bar/slot so I took the time to do a far amount of measurements of both of my slots. I took a reading every inch on both slots using my miter gauge and feeler gauges. When I couldn't get a feeler gauge in then I went back down .001 and if that fit then I had a measurement. I tried to use a fixed spot on the miter bar for all measurements and the feeler gauge to the outside side of the table.

The slot on the right is a little larger then the one on the left. The maximum I found was .008" but most readings were at .003 to .004. In all cases I could slide a feeler gauge in.

I think I recall Nick saying the bar for the dial indicator was .004" undersized but I don't know how that relates to the miter bar on the miter gauge. If I have time tomorrow I'll do a series of measurements on the miter bar and the dial indicator bar.

Ed

dusty · Post by **dusty** » Mon Oct 01, 2007 5:41 am

As I read through this post I was reminded of an earlier thread on the same subject. The similarity in readings (tables and miter slots) is especially interesting.

http://www.shopsmith.net/forums/showthr ... ight=Miter

ed, have you checked the miter bars themselves for straightness?

I have checked along the sides of my miter bars while installed in a miter track with a feeler gauge. The clearance is NOT consistent from one end of the bar to the other and the clearance is not similar (at a given point) from side to side.

If you scrutinize your 520 fence (the 510 also) you'll find the same order of deviations. The left side of my fence appears to be straighter than the right side - when tested using a dial gauge running in the miter tracks.

NOTE: We're talking about deviations on the order of .001" to .003". Is this enough error to be concerned with? IMHO, this is proof positive that the Shopsmiths (all of them that have been put through this rigor) are pretty close to the same.

Frankly, I'm favorably impressed.

reible · Post by **reible** » Mon Oct 01, 2007 1:35 pm

dusty wrote:As I read through this post I was reminded of an earlier thread on the same subject. The similarity in readings (tables and miter slots) is especially interesting.

https://forum.shopsmith.com/viewtopic.php?t=539&highlight=Miter

ed, have you checked the miter bars themselves for straightness?

Hi,

No I have not checked the bars for straightness, the best I could do would be agains another straightedge and I'll do that but I don't expect it to be off enough to see. I will check the width in 1" steps for the whole length but since this is a "machined" part I expect it to be very close as well.

I have checked along the sides of my miter bars while installed in a miter track with a feeler gauge. The clearance is NOT consistent from one end of the bar to the other and the clearance is not similar (at a given point) from side to side.

I did this in 1" steps using the same spot on the miter bar... this takes the miter bar out of the equation and yes the numbers do change, that is where the .003 to .004 numbers came from.

If you scrutinize your 520 fence (the 510 also) you'll find the same order of deviations. The left side of my fence appears to be straighter than the right side - when tested using a dial gauge running in the miter tracks.

I'm not sure how you did this?? I have however did the straightedge against the fence and do not see any "light". I don't think you can use the miter slot as something to measure against... maybe if you have a known straightedge and put that against the fence and ran the dial indicator base against the straightedge and took readings that way??? If you use the miter slot how do you sort the miter slot differences from the fence differences?

NOTE: We're talking about deviations on the order of .001" to .003". Is this enough error to be concerned with? IMHO, this is proof positive that the Shopsmiths (all of them that have been put through this rigor) are pretty close to the same.

I don' think anyone here is concerned with the deviations, however, when shopsmith sells us a tool we can certainly play with it and learn more about out system using it.

The interest in seeing more numbers is to see if they do vary more then the few we have seen. Someone with a 10 year old table as compaired to a table like mine that is only 3 years old.... In fact if I had a way of setting up my old 500 that has had years of use it would be interesting to see how it fairs.....

Anyway the "errors" are not there, the numbers we have seen so far are "tolerances". When doing engineering drawnings one gives a tolerance to parts, so for the miter bar it may say +.000 -.005 and the slot might be -.000 +.005.... To be honest I'm not impressed, it is just like it should be, as in "done right", like we should expect.

Frankly, I'm favorably impressed.

BTW the "slop" we are talking about is what causes the bar to wiggle in the slot and is what some people worry about causing their cuts to be off. I have measured for this as well and on my system this amounts to in the range of .043 deg. total. OK NASA is not going to use this to send off any deep space probes but it is close enough for general woodwork, ah?

Ed

charlese · Post by **charlese** » Mon Oct 01, 2007 7:39 pm

Just re-read my post #5 (above):o Whoops! Guess I'm not used to such fine/small measurements, but found out that one little line on the dial indicator is 0.001" - not 0.01". So that confession being made - the slop in my dial indicator bar inside of the miter guage slot is +0.001" and - 0.001". Total slop .002". So my observation is still correct - there is not much slop.

Also, please excuse the wording in my post Number 5. I meant to refer to the dial indicator bar - not the miter bar slop.

I will undoubtedly use the dial indicator if I ever have to re-align the main table. I will also use it to periodically check on the alignment of the fence, but other than those uses, it'll probably stay in the drawer. Never could understand why woodworkers wanted (demanded) tools that cut to the nearest 1/1,000 of an inch. Still can't!

Like said above, The dial indicator is a new offering by Shopsmith. It deserves to be used for testing various alignments of our Mark Vs. It's use is kinda fun, but rather redundant, if setups using a square and straight edge were done according to Shopsmith instructions.