Dykem Hi-spot

[pkastagehand]

So, does Hi-Spot have a shelf life? I once had some layout dye that got so old it didn't work...

I was thinking I would try to improve my imported mill vise and was trying to use some Hi-Spot and found that it was almost impossible to see any blue on the part after sliding on the surface plate. It transferred because I could feel it and see the residue on my finger, and it got the rag blue to some extent when I wiped it off. But it was so pale I couldn't read it.

I looked for other threads about transferring dye when scraping but couldn't

 

[goldstar31]

My years old layout dye is still OK to use. Perhaps the solvent has evaporated on yours.

As far as a merest trace of blue for scraping, that's what it all about. If you read Connelly he suggests using a red oil based paint as an undercoat and of course a bright light to scrape to. Connelly and his book has been raised and raised in this forum.
What you are looking for is not the blue but the bits which have been rubbed away as 'high spots'. OK, I live in the UK, very ancient and my eyes are now useless but that is where I went in the past.

Having written this, I hope that I haven't told you something you know, if so please accept my apologies.

Norm

 

[canadianhorsepower]

simply use a sharpie, does a better job at 1/4 of the price

 

[TonyM]

The sharpie is OK for marking out but not to replace High spot which is the same as Micrometer blue. I had some for years and it was OK. Maybe the vice is better than you imagine. I used the wifes dark lipstick once when I couldn't find the micrometer blue. That worked OK too.

 

[ShopShoe]

What you are looking for is also known (In the USA, anyway, as Prussian Blue). Check with a well-stocked Auto Parts dealer. Your High-Spot paste can be purchased at McMaster-Carr. Also did a search under "Prussian Blue" and found it can be ordered from Walmart.com

Also, Tom Lipton (oxtoolco on YouTube) suggested substituting an artist's pigment for these uses, an idea suggested by his artist wife. I'm sorry, but I can't provide a link to the video where this came up.

I have used the paste for years for checking fits and mating finishes and it is a little old-school but will work very well.

--ShopShoe

 

[TonyM]

Out of curiosity I did a bit of digging and both products are Prussian blue based.
Layout blue is Prussian blue mixed with alcohol
Micrometer blue is Prussian blue mixed with a grease.
You live and learn.

 

[goldstar31]

deleted

 

[Neil Lickfold]

The bearing blue is either a oil like baby oil, or some brands use linseed oil. Over time they can dry out , especially the stuff sold in a tin, or when the cap cracks.

 

[GrahamJTaylor49]

In the UK the oil based blue for finding high spots was and still is known as "Micrometer Blue" and comes in a small round tin about 2" diameter.
As an engineering apprentice we found that if the blue was put on the handle of the college instructors bench vise he could get it all over his white shop coat before he realised he had transferred it and everything he touched had the blue on it. Still have a tin of it in my workshop.

 

[goldstar31]

For those with a pecuniary embarrassment , the tins in the UK are all of £5+-- or change out of an Irish £7 note

 

[GrahamJTaylor49]

I have no idea of the current price as I bought my little tin well over 20 years ago. Mind you, it's still ok.

 

[Wizard69]

Maybe the surface is too flat to leave blue. As someone mentioned above the idea with bluing is to find the high spots that get polished off with the blue left in the low spots. Also ground surfaces are often hard to read giving very low contrast.

 

[goldstar31]

Maybe the surface is too flat to leave blue. As someone mentioned above the idea with bluing is to find the high spots that get polished off with the blue left in the low spots. Also ground surfaces are often hard to read giving very low contrast.

The cost of NEW stuff is trifling anyway

 

[ALEX1952]

The despicable behavior of GrahamJTaylor49 putting blue on a vice handle is not to be encouraged! far better in my opinion is what we used to do as apprentices was to coat the telephone earpiece therefore is was not apparent and with luck claimed more than one victim sadly with modern phones the scope for use is limited, and probably in today's environment litigious in some way. As my surname is Taylor I dont believe there is a connection.

 

[ALEX1952]

If using high spot to get something flat as opposed to matched the surface you are checking should be rubbed on 2 known flat surfaces as only using one can lead to errors if the master has an error, this is how surface plates are scraped.
Machine ways etc of high quality would be scraped and when I was tought we were looking for 20 random high spots (no blue) per sq inch the low spots could be as blue as you like within reason as this aids oil retention and stops sticking therefore reducing loads on the machine (just think about inspection grade slipsand how they wring together).

 

[Wizard69]

If using high spot to get something flat as opposed to matched the surface you are checking should be rubbed on 2 known flat surfaces as only using one can lead to errors if the master has an error, this is how surface plates are scraped.
Machine ways etc of high quality would be scraped and when I was tought we were looking for 20 random high spots (no blue) per sq inch the low spots could be as blue as you like within reason as this aids oil retention and stops sticking therefore reducing loads on the machine (just think about inspection grade slipsand how they wring together).

Exactly this when scraping. On a well ground surface you will not get the low spots thus a good portion of the bluing rubs off. If there are low spots the bluing is so thin that no contrast is there to be seen. The OP may simply have a piece that is too flat to leave high contrast highlights.

Even when scraping to very high levels of flatness contrast can become a problem, especially for old eyes. I’d need to see picture to know for sure what is going on here.

 

[Neil Lickfold]

Some bearing blues are not very good when looking for very small amounts, these I have found are the ones that are too wet. It is like the blue capillary attracts to areas not wanted. But the same blue, that has had a wick put to it, to draw out some oil, then becomes good to use. This is the case when looking for differences that are less than 0.01 mm. One of the better blues I have used is the Stuarts blue in a small flat tin from the UK, another that was really good was the Gud bearing blue. Not sure where that is from. The most recent batch of Dykem tube I had was just way to oily for my liking, but was fixed by wicking out some of the oil.
Reading blue can be an art in itself, especially looking for the high pressure areas compared to the lower pressure areas. The low pressure area will be darker in colour and thicker. The high pressure area is thinned out and more faint. The excess runs or flows to the low areas. That is why if you apply too much movement, will also give a false indication as to where is hi and low. It also needs to be applied evenly but very thinly. To do this, I use a short paint brush and stipple the blue onto one of the surfaces. I do not put it on like a painted surface. It is applied like a lot of series of small dots close together. It leaves room for the expansion of the close areas. That is my take on it, and how I use it.
Neil

 

[ALEX1952]

The Stuart blue (Chronos sell it in the UK it lasts forever) I have found to be very good it needs to be the consistency of petroleum jelly (Vaseline) as to method of application you can't beat a finger your going to get in on you anyway, apply as you would a very thin smear of ointment to the skin to thick and it defeats the object, you are looking to push excess into the low spots leaving the un-coated high spots, to much and you just get a blue surface with very little contrast less is best and I'm sorry to say experience which the model engineer might have trouble getting unless you are prepared to get a lump of mehanite (high quality cast iron) and practice. During the hard labor called an apprenticeship we spent 3 months learning the art of scraping of all types and you think you know it all until the guys come in to recondition and certify the surface plates and tables you felt like chucking your tools in the river, one of these guys took the time to show me how to put a curl (crescent shape pattern) 0n the finished surface hopefully it stayed flat, I can still do the pattern but probably not scrape flatbit's one of those skills you need to "keep your hand in"

 

[pkastagehand]

Bad timing on my part. I asked the questions then left for vacation not thinking about no internet; except by phone and this much typing on a phone is tedious at best.

Judging by responses, I'm thinking my blueing (Dykem Hi Spot) is OK, though maybe not the best choice. It might also be, as a couple of you pointed out, that the surface isn't as bad as I thought it might be.

I was keeping it thin, because I knew about over coating causing false readings and I could tell it was transferring but it was just about impossible to see which made me wonder if it was something to do with pigment breakdown over time. I should do some practicing on other objects to learn to read it.

For now I've put the vise back together. It isn't as bad as I'd thought. I did have to rebuild the thrust bearing collar and replace the bearing.

Thanks for all the replies.

P-

 

[Wizard69]

In the past I never had an issue with Dykem Hi Spot but that doesn’t mean quality control went out the Window.

Part of the trick with spotting is, as guys pointed out above, is to apply the spotting material in very thin layers, the material should almost be transparent on your reference surface. On a precise surface it does become more of a challenge to see the high spots. As noted the high spots should be bright with the low points filled In with blue. It is when you have a tiny difference between high and lows that contrast becomes a problem. Professional scrapers will sometimes switch over to higher contrast materials, in place of Dykem, as surfaces get flatter.

Bad timing on my part. I asked the questions then left for vacation not thinking about no internet; except by phone and this much typing on a phone is tedious at best.

Judging by responses, I'm thinking my blueing (Dykem Hi Spot) is OK, though maybe not the best choice. It might also be, as a couple of you pointed out, that the surface isn't as bad as I thought it might be.

I was keeping it thin, because I knew about over coating causing false readings and I could tell it was transferring but it was just about impossible to see which made me wonder if it was something to do with pigment breakdown over time. I should do some practicing on other objects to learn to read it.

For now I've put the vise back together. It isn't as bad as I'd thought. I did have to rebuild the thrust bearing collar and replace the bearing.

Thanks for all the replies.

P-