dial indicator fix?

[Gene Tereba]

I have a new table saw that I wanted to check for accuracy and alignments. I have a HF dial indicator and I was checking the fence and slot alignments and keep getting differing reads. As a result, think the HF dial indicator is worthless trash and inaccurate cause never same reading twice.

Other than buying a new Dial Indicator (which is fine but can get costly for a good one), any "tests" or ideas on how to check alignments or accuracy issues.

Looks like my next step might be a GOOD dial indicator....thoughts?

thx

[Garrett Ellis]

Can you do some more testing with the HF dial indicator, maybe against some known values?

I used a HF dial indicator to realign my old craftsman contractor saw and it worked great for me. However, my fence/blade were not great to start with so any realigning was an improvment.

The accuracy of the indicator is not really important as long as it is consistent... I think I bought a HF indicator based on recommendations from other users here.

[Jay Maiers]

I would think you could get decent results using a block and a set of feeler gauges (the shim style, not the fine wire type). It'll probably be a PITA, but feeler gauges are pretty cheap and useful for many purposes.

If you decide to replace the gauge, decent Starret indicaters are widely available on fleabay for reasonable prices.

[Thomas Hotchkin]

You can take the back off the indicator and clean it with a spray contact cleaner on the input shaft and re-lube with very light weight lube oil (not WD40). Tom

[Gene Tereba]

thanks for advice...

any specific feedback from others about consistency and reliability of HF indicator?

[Chuck Wintle]

Cheap dial indicators could suffer from a variety of problems and one is the quality of the internal gearing. Good ones likes starret or mitutoyo don't have this problem.

[glenn bradley]

I have used nothing else for a couple saws, a jointer and a couple planers. No problems. Generally when I am getting different results from the same check, its not really the same . . . The miter bar isn't shimmed, the spot I'm checking isn't exactly the same, a bit of grit has gotten under the supporting platform and so forth. I suggest screwing the dial indicator to something that you know is holding still and take repeated measurements of the same thing, 10 or 15 times. If it is not consistent, then I would blame the indicator and look for a replacement.

Remember that when aligning a machine we are often looking for a differential reading as opposed to an actual one. That is, measure to one spot and zero out there, measure in another and watch for variation or check for variation as we move across a surface and such. HF has a few diamonds in the rough and my gauge has certainly earned its keep. I did pick up a set of tips from the Little Machine Shop for a fraction of what others charge for the same set. This alone solidified my ability to read differing surfaces with more confidence.

[Bruce Wrenn]

I own several DI's. Most are from HF. For woodworking they are more than enough. I have several jigs that use DI's so I just mount one to each jig to save precious time. If you are using a magnetic base with the adjustable arms, that is most likely where your problem is occurring.

[Ronald Blue]

When using an indicator whether its a plunger style or dial test it is important in your setting to keep the slider bar pushed against the same side of the slot each time and use the same measurement points each time. If after doing so it isn't repeating then the indicator may indeed be junk. As someone else mentioned consistency and accuracy are different. You don't care if a rotation on the dial is an exactly what it says it is if it repeats itself consistently. Good luck.

[Josiah Bartlett]

Many times when people blame the dial indicator, it is the mount that is flexing. Make sure that is stiff enough before you blame the dial indicator.

[John Coloccia]

Some of these were already mentioned, but I thought I'd gather them all up into one post, and maybe add one two. The main sources of error (other than the indicator, but that's probably not the culprit) are:

1) slop in the miter slot. The bar needs to be against the same side of the slot every time
2) the indicator's mount. It must be rigid
3) runout in the blade: mark the spot on the blade you're measuring to with a Sharpie. When you measure your second point, rotate the blade and use the same exact spot. The blade runout will likely be more than you think. I'll bet that you have around .010" runout between the arbor, the flange and the blade. To test this, hold the indicator in one place, and spin the blade around. That will give you the total runout.

#3 is the one that could have you chasing your tail if you're not thinking of it. It had me chasing my tail, at any rate.

[david brum]

I think the biggest problem with HF indicators is the pointy tip. It is nearly impossible (for me) to hit the same spot on a saw blade, jointer blade, etc in order to get some kind of standard. I bought some flat tips at Enco for pretty cheap which made all the difference. They also have decent cheap indicators if you still want to chuck yours.

I think I bought this one http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=5802335&PMAKA=325-1380

[Bo McCorkle]

i just use cheap chinese dial indicators at work (im a machinist) that way when i forget to move them out of the way its no hige loss like the first starret thet happened to. try msc or another indutrial supply and by a couple

[Gene Tereba]

whats a spray contact cleaner? never heard of such.... brand name?

[Adam Strong]

I also use a HF DI in the shop and agree the tip makes all the difference. A clean/lube of the internals was needed on mine out of the box. I disassembled the workings and cleaned them (as a former engineer, I have repaired many in the past) and reassembled using a dry lube spray. I have not had one issue since.

[Jay Maiers]

whats a spray contact cleaner? never heard of such.... brand name?

I think he's talking about an electrical contact cleaning solution. It also happens to be a pretty good degreaser and general cleaner.
http://www.amazon.com/DeoxIT%C2%AE-DN5-Mini-Spray-nonflammable-solution/dp/B000RGD9PK

[Lee Schierer]

thanks for advice...

any specific feedback from others about consistency and reliability of HF indicator?

I found my HF dial indicator to be pretty consistent. What I did find was that slop in my miter track and mount ing of the indicator caused errors to come in before I tightened everything up. I always mark the starting spot so I can move the indicator to another point and return to the start point to verify the reading stayed the same. You also need to remomeber you are aligning a table saw and that readings don't have to be absolute zero......

Don't try to take reading off the teeth of the saw. Most teeth are tapered on the sides and it will not give you consistent readings. Mark a blade just below the tooth gullet and use that area for your readings.

[Tony Bilello]

Exactly how are you taking your measurements?
As others have stated, the problem could be slop in your track or flex in your testing system.
If you are satisified with you test system, buy another dial indicator and compare results.

[Bryan Morgan]

I have used nothing else for a couple saws, a jointer and a couple planers. No problems. Generally when I am getting different results from the same check, its not really the same . . . The miter bar isn't shimmed, the spot I'm checking isn't exactly the same, a bit of grit has gotten under the supporting platform and so forth. I suggest screwing the dial indicator to something that you know is holding still and take repeated measurements of the same thing, 10 or 15 times. If it is not consistent, then I would blame the indicator and look for a replacement.

Remember that when aligning a machine we are often looking for a differential reading as opposed to an actual one. That is, measure to one spot and zero out there, measure in another and watch for variation or check for variation as we move across a surface and such. HF has a few diamonds in the rough and my gauge has certainly earned its keep. I did pick up a set of tips from the Little Machine Shop for a fraction of what others charge for the same set. This alone solidified my ability to read differing surfaces with more confidence.


I made a device almost exactly like the one you have here and I used the HF dial indicator as well. No problems with mine at all. Maybe the one Gene got was just a dud.