AdrianR | 16/07/2019 12:39:16 |
613 forum posts 39 photos | For scraping I use Stuarts Engineers Blue. For marking up I use permanent markers. As my ancient and very nice smelling marker finally dried up I had to buy some more. I have found Wilko black permanent markers are very good, and they dont seem to worry too much about slightly oily surfaces. At £1 for for pens good value too. As others have said, it does rub off but usually enough remains for me to finish the job. To clean up it just needs meths on a tissue. Also the fact they do rub off is of use. Great for checking mating surfaces, it was invaluable when recently making a morse taper. One day I am sure I will need to more complicated marking out, then I will buy the proper marking out fluid.
Adrian |
Lainchy | 16/07/2019 12:49:45 |
![]() 273 forum posts 103 photos | Posted by SillyOldDuffer on 16/07/2019 12:18:43:
Not critical. My sample was mixed in an eggcup with a blob of Stuart's on the end of a table-knife. The dye is almost certainly Methylene Blue which dissolves readily in alcohol. Stuart's slow-drying paste is formulated stiff for scraping, but adding Meths thins it down considerably and it becomes quick drying. You can experiment for best results. Not as good as real marking blue or a decent felt tip, but worth a try. My tiny tin of Stuart's looks as if it will last me forever and I didn't feel bad about repurposing some of it. In theory it should be possible to dissolve ball-point pen ink in the same way. In practice, more trouble than it's worth! Dave Edited By SillyOldDuffer on 16/07/2019 12:19:34 Cheers Dave
|
SillyOldDuffer | 16/07/2019 13:09:28 |
10668 forum posts 2415 photos | Posted by AdrianR on 16/07/2019 12:39:16:. ... One day I am sure I will need to more complicated marking out, then I will buy the proper marking out fluid.
Adrian For me marking out was very helpful with hand-tools and for manual setting operations like centre-popping ready for the pillar drill. Now I've got a mill I do much less marking out than before, especially since adding a DRO. Drilling with a mill I don't centre-pop, and - because the work is mounted on a precision table - I usually cut direct from the paper drawings relative to reference points established on the actual work. Not much need to mark out now, though it does help prevent silly mistakes. For that purpose I often scratch guide marks on odd blobs of felt-tip, but it's not really proper marking out at all. Apart from blobbing, another advantage of felt-tips over proper marking fluid is colours. I have some sort of blind spot causing me to cut mirror-images and colour coding helps reduce blunders. Marking out might be unfashionable in my workshop only because of the type of work I do. Do others find elaborate marking out useful and if so, what for? Dave
Edited By SillyOldDuffer on 16/07/2019 13:09:51 |
SillyOldDuffer | 16/07/2019 13:11:10 |
10668 forum posts 2415 photos | Whoops - double post deleted Edited By SillyOldDuffer on 16/07/2019 13:13:53 |
mechman48 | 16/07/2019 13:17:17 |
![]() 2947 forum posts 468 photos | Posted by Bill Pudney on 16/07/2019 11:26:43:
My experience of scraping goes back to my apprenticeship in the 60s. Way back then the best results were had with a VERY light application of blue, it seems to me that any sort of roller would put on far too much. But I may be wrong, it has happened before according to The Boss. cheers Bill Snap!... me too, but we used to roll up a pad of cloth into a firm ball then dab it on to the 'engineers blue' tin then dab it onto the surface plate evening it out before placing the object to be scraped on to the plate, a couple of light pushes brought up the high spots that needed scraping, repeat until 'minimum' of 25 points per sq. inch was achieved, we usually aimed for a lot more, before the charge hand accepted it. George. |
Rik Shaw | 16/07/2019 13:42:54 |
![]() 1494 forum posts 403 photos | Stuarts blue if I wanted to get a "witness" but for general marking out I use copper sulphate . Rik |
Pete Rimmer | 16/07/2019 13:57:01 |
1486 forum posts 105 photos | Posted by Douglas Johnston on 16/07/2019 11:04:46:
I have been trying out some scraping lately and saw on youtube that some people use a roller on the surface plate to spread the blue indicator over the surface. I was thinking about trying that but can't find any reference for the type of roller needed. There seem to be hard rubber rollers and soft rubber ones and probably ones in between. Is there a scraping mastermind out there that can recommend a suitable type of roller? Doug You can use a foam roller or an ink roller (plastic roller with a rubber sleeve over it). The foam gloss rollers work OK for water based spotting blues but I prefer the ink roller for oil based like stuarts. When rolling out the ink I tend to load the roller by putting a db of blue on a small plate and rolling it out then using the loaded roller to lie the part or plate. |
Douglas Johnston | 16/07/2019 17:43:30 |
![]() 814 forum posts 36 photos | Thanks for that Pete, I should probably have started a new topic rather than stick my question on the end of an old topic. My question about rollers got swamped by the previous discussion. I will see if any local arty shop has rollers I can look at otherwise it will have to be pot luck on fleabay. Doug |
Gordon Smith 1 | 16/07/2019 17:51:24 |
45 forum posts 2 photos | I got my roller and water based colour from Amazon. Gordon |
Douglas Johnston | 17/07/2019 08:53:50 |
![]() 814 forum posts 36 photos | Thanks for that information Gordon. I had a look on the Amazon site and easily found rollers but could not find the water based colour you mentioned. Could you give me any more information about what to search for on the Amazon site. I am looking on the Amazon-UK site by the way. Doug |
Iain Downs | 19/07/2019 09:44:45 |
976 forum posts 805 photos | I've spent some time using the sharpie approach, for marking, but not found it very useful for other than simple tasks. As soon as cutting fluid hits it, it's gone. At the last show I invested in some dychem marking blue and it's been great. The only drawback is that it takes longer to dry than the sharpie.
Iain |
Mike Poole | 19/07/2019 10:37:04 |
![]() 3676 forum posts 82 photos | I think the Sharpie and Dychem options are both useful but horses for courses applies. I find Sharpie very useful but its durability is poor, even handling the part wears the colour off but the scribed line does persist just not so easy to see. Mike |
Cabinet Enforcer | 19/07/2019 11:52:21 |
121 forum posts 4 photos | Posted by Douglas Johnston on 16/07/2019 11:04:46:
I have been trying out some scraping lately and saw on youtube that some people use a roller on the surface plate to spread the blue indicator over the surface. I was thinking about trying that but can't find any reference for the type of roller needed. There seem to be hard rubber rollers and soft rubber ones and probably ones in between. Is there a scraping mastermind out there that can recommend a suitable type of roller? Doug I think you probably should have started a new thread Doug...
Try looking for the term "brayer" as that's the proper name for an ink roller, as the "ink" is quite thick and the surfaces hard, you will need a pretty firm roller to ensure an even spread. |
Trevorh | 19/07/2019 12:00:39 |
![]() 316 forum posts 89 photos | Doug if you search for hand rollers for the printing industry - you will need something like a 60+ shore hardness we use these to apply flexo printing plates to the cylinder's as well as the ink tech's use them when taking a draw down of the printing inks cheers Trevor |
Gordon Smith 1 | 19/07/2019 14:44:33 |
45 forum posts 2 photos | Doug The Prussian blue etching ink I got is manufactured by Cranfield and is oil based but washable with water. If you look at Tom Lipton's site on You tube he discusses the use of these type of spotting media. Gordon |
Douglas Johnston | 19/07/2019 20:05:41 |
![]() 814 forum posts 36 photos | Thanks for the useful replies, a new thread would have been a good idea to separate the Sharpie type markers from the stuff for scraping. I have been spreading the blue I have with an applicator I found on the end of my hand and it seems to be OK if a bit messy, so I will check out a roller to stop leaving blue fingerprints everywhere. Doug |
Michael Cox 1 | 19/07/2019 20:59:06 |
555 forum posts 27 photos | Posted by Lainchy on 16/07/2019 12:49:45:
Posted by SillyOldDuffer on 16/07/2019 12:18:43:
Not In theory it should be possible to dissolve ball-point pen ink in the same way. In practice, more trouble than it's worth! Dave Edited By SillyOldDuffer on 16/07/2019 12:19:34 Cheers Dave It is easy to make a marking out blue as follows: Take 50 ml of French polish and add 50 ml of methylated spirit. Now take a cheap blue ball point pen and pull out the nib and ink tube. With a pair of sharp scissors chop the ink tube into pieces about 12mm long and let them drop into the mixture of French polish and alcohol. Shake the mixture and leave to stand for a day. The mix is easily applied by a small brush and it is quick drying. It marks easily with fine scribe. It is resistant to water based and oil based complaints and cutting fluids. Mike
Edited By Michael Cox 1 on 19/07/2019 21:00:43 |
Nigel Graham 2 | 20/07/2019 22:54:18 |
3293 forum posts 112 photos | On rough surfaces such as hot-rolled steel or cast-iron, where I don't need a fine line for the first operation at least, I have sometimes degreased the metal then applied a spray primer (ordinary car paint) or strip of masking-tape and marked out with a sharp pencil. For removing marking-out fluid or paste blue, use methylated spirits; ditto for cleaning the artist's paint-brush with which I apply the fluid. |
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
Sign up to our newsletter and get a free digital issue.
You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.