Distance Scales

[Anorak Bob]

For a while I have been wanting to make, or have made by others, a set of metric scales for my mill. I contacted a firm over here that etches stainless. I was quoted a minimum charge of 200 dollars. For that price I could have ten scales made. I need three.

The original imperial scales are matt chrome plated. Clear satin anodised aluminium would be closer appearance wise than stainless. Aluminium is easier and cheaper to work with.

I have been in communication with Mark "Graziano" Harriss. Mark showed us some of his superb etched reproduction nameplates last year on this forum. Mark feels that distortion of the masking used during etching could be a problem given the largest scale is 310mm in length. There is information on-line regarding the use of printed circuit board masking film as a resist for etching various metals. There is also information regarding suitable chemicals for etching aluminium including those used by printmakers. That's one option.

The second option is the scribe the millimetre lines, three different lengths, and stamp the numbers. The greatest problem would be achieving a uniform depth of impression with the stamps. Puerile results would be easily achieved.

The third option is to try and make a simple pantograph that utilizes a Dremel and lettering stencils rather than traditional engraving fonts. I have numerous stencils. There was a book available on Ebay dealing with the construction of a home made pantograph as described. I didn't buy it.:doh:

All options have their merits ( and shortcomings ).

Schaublin engraved the originals, perfectly.

I'm leaning towards the pantograph. Any suggestions?

BT

[markpest]

Bob, presume you saw the article in MEW #178. p16-20 re chemical 'milling'. Again, it has is drawbacks. (If you missed it whilst you were away travelling, I'll scan if you wish) Mark.

[Michael G]

Have you spoken to any firm that does laser engraving? It may be on the pricy side but could give you what you want.
I understand the issue with using metal stamps for graduation, but was able to make up a jig to do a handwheel and with some practice got passable results. Provided the stamps line up indexing should not be a problem and then the only trick is working out how hard to hit the stamps. I soon discovered that 1 required less than say 8 - it can be done. Clamping the item being stamped is essential as otherwise it can jump when stamped.

Michael
190393

[burraboy]

Perhaps an engravers pantograph with an indexing head would be ideal but I don't know where you would find that combination. Talk to trophy engravers and see what they suggest.

[Greg Q]

Its for occasions like this that I always wish I had a small CNC router...A vee bit would make quick work of a project like this I reckon.

I bought some lacquer sticks for filling in the graduations with colour...they seem to work well and are only a couple of bucks. Are you planning black if anything?

Greg

[Anorak Bob]

I might have it covered. A local fellow forum member has generously offered me the use of his pantograph. From memory, a Taylor Hobson.

BT

[Stustoys]

Hi BT,
There's a Dekel 2D Pantograph over this way for $700, you know you want it!
Alum is pretty easy to scratch. How about S/S thats been sandblasted?
How thick and wide are they pieces you are making?

Stuart

[Graziano]

Hello again people, I just thought I'd throw my two cents in: A guy I know made an estimated 30 000 faceting machines (hmm I'd better confirm that figure...might be 3000+, Hall Faceting machines) and telescopes over about 40-50 years locally with hand scribed lines on protractors, indexing wheels and marked knobs using a hand shaper and a rotary table with a Geneva mechanism for fixed indexing. The rotary table can be set up to do flat circular arcs and at 90 degrees handle cylinders and the conical bevels on cylindrical adjuster knobs.

I'd imagine a home made version of a hand shaper to scribe lines, with a screw or maybe a ratchet and pawl to advance the scale, even with a digital linear scale. once you get a rhythm going it would be even faster than doing it with etching and the linework is definitely superior. If anyone is interested I can take photos of the setup today when I'm in town.

http://www.lathes.co.uk/adeptshaper/img0.jpg

[Anorak Bob]

Thanks for the suggestions fellas.

Mark Harriss just sent me a very informative message regarding the etching process that he has used and refined. Mark is concerned that the PCB film technique may not produce the crisp lines I'm chasing.

Mark "Markpest",
I am interested in the scanned article and I am sure others would be.

Michael,
Whilst being most probably the simplest option, my concern regarding stamping is that the end result might just look like that, hand stamped. I had better post some photos of the existing scales. I do have a simple jig I used when stamping the degrees on a vise base. I should set it up to ensure verticality of the stamp and give it a go before I dismiss the idea.

Burraboy,
I contacted a nameplate engraver the other day and he was the one that suggested etching as a less expensive alternative to pantograph engraving. Previously I had contacted another firm of engravers regarding engraving my Hercus rotary table. Their quote encouraged me to do the job myself. Scribed and stamped.

GQ,
The lines and numbers are black paint (?) filled. Just like on the FP1. Can you tell me more about the lacquer sticks?

Stu,
Of course I'm interested. Can you wire me some details?
The original scales are 12mm wide and from memory, 2mm thick.

BT

[Anorak Bob]

Mark,

You replied while I was one finger typing. I'd love to see more photos.

Bob.

[RayG]

Hi BT,

I have a bit of experience making PCB's and used to use UV sensitive films and sprays a fair bit, like all things there are a few tricks, the first one is if you print on a clear film, then make sure it's mirror image reversed, so that the side that's in contact with the etch resist is the printed side, otherwise you get a bit of bleed through caused by the thickness of the film, second the etching times are critical as is agitation, bubble bath type etching tanks are the best way to go. I used to use Amonium Persulphate for etching copper. Ferric Chloride is ok, but hard to see what's happening.

You can maintain PCB track widths and clearances of 8 thou quite happily with a bit of care using a relatively simple home setup.

Those days are (happily) long gone for me, nowadays I send the gerber files to a place in China and I get back boards in a week. At ridiculously low prices and excellent quality I might add.

For your scales, I'd suggest you would get crisper sharper lines with a mechanical engraving process compared with chemical etching.

I like Greg's suggestion of a small cnc router, there are a lot of people who have that sort of equipment for engraving signs and plastic labels, it would be worthwhile seeing who is in your area doing sign engraving type work.

Another idea, that might be worth investigating is a laser etch, I have got laser cut sheet metal with witness marks for alignment marked on the sheet with the laser, sort of a low power cut, it probably has a name, but I don't know what you would ask for, laser engraving perhaps?

Regards
Ray

[Greg Q]

GQ,
The lines and numbers are black paint (?) filled. Just like on the FP1. Can you tell me more about the lacquer sticks?


BT

Better, PM me your postal address and you'll be able to experiment yourself.

Greg

[Anorak Bob]

I am keen to make up a rough (as in millimetre accuracy, hopefully not rough in execution) distance scale, holder and pointer for the Z axis on my 13. The attached photo of a later model 13 shows the scale and pointer. My mill does not have the vertical tee slot shown in the photo. I want to try and incorporate a slot in the scale holder to enable the attachment of a dial indicator. The two shorter scales would replace those on the X and Y.

BT

http://www.woodworkforums.com/attachment.php?attachmentid=190433&d=1323319985

[RayG]

Hi BT,

Do you have the DRO on yours? Very slick looking machine by the way..

Regards
Ray

[todd_aust]

If this is still a requirement I can probably assist on the cnc front, a bunch of engraved lines and some lettering shouldn't be an issue in aluminium...

Sent from my GT-I9100 using Tapatalk

[Michael G]

One thing I have done (to howls of protest I might add) for flat scales is get some steel rules of the appropriate graduation and cut/ grind/ machine them to the right size. You get accurate marking, very neat graduations and they are usually not very expensive.
This place -
Steel Rules, Ruler Stops (http://www.fine-tools.com/mass.htm)
although I've never used them seems to carry every rule under the sun. Mcmaster Carr also have a wide range.

Michael

[Anorak Bob]

Hi BT,

Do you have the DRO on yours? Very slick looking machine by the way..

Regards
Ray

Nah Ray ,
Mine's an older style!

http://www.woodworkforums.com/attachments/f65/187891d1321346422-not-dro-indicator-instead-indicator-bracket-revision-15-11-2011-014-large-.jpg

Michael,
I've done my rounds of the hardware stores and looked on-line for an easy option but there is nothing that comes close to the original scales. Being anal about these things doesn't help but that's me.

Todd,
Here is a rough pdf of the shortest scale. Some refining is still required. The circles indicate the screw fixing locations.

[Michael G]

This is the best match that Mcmaster can do, but might do in a pinch -

Michael
190445

[ian63]

Bob, Where I used to work we had an Epilog laser engraver which we used to make stainless steel name plates. We would get stainless with a polished finish on one side, spray with some stuff called Cermark and then run it through the laser. This would leave black lettering on the stainless plate, not sure exactly what the process is that causes the stainless to go black but it seemed to work well. (A google search for Cermark will show what can be done). The laser can engrave to a really fine level so should work OK for producing a scale for you. The company we bought the laser from in Sydney, Project Engraving, have an office in Perth. It may be worth while giving them a call to see if they can put you in touch with one of their customers. I am sure that it would only take a matter of minutes to set up and engrave, you may have to drill your own holes though.

[Stustoys]

Hi BT,
Who'd want a scale in cm? hehe

PM set ages ago.

Stuart

[markpest]

Thanks for the suggestions fellas.


Mark "Markpest",
I am interested in the scanned article and I am sure others would be.


BT

Hopefully of interest. I was impressed as "not excessively toxic." All the best with this one - as always look forward to hearing / seeing the final pics. Mark

[markpest]

Last installment Mark

[Graziano]

As promised here's the photos of how markings were engraved with a hand shaper which is more or less the only use for a small hand shaper. The 96 tooth index wheel is not made this way but hand stamped and faced off to smooth out the edges of the stamped numbers. The brass knob is made using the hand shaper and then stamped using a jig to hold the numbers in position.

The hand shaper bolted to a steel channel back and a cast iron channel base (made back when you could buy cast iron easily).

http://www.woodworkforums.com/attachments/f65/190530d1323440424-distance-scales-engraving-brass-600.jpg


A brass knob mounted in the rotary table chuck being engraved with lines.

http://www.woodworkforums.com/attachments/f65/190531d1323440424-distance-scales-hand-shaper-engraving-600.jpg


Another shot showing detail of the shaper depth adjustment and clapper box.

http://www.woodworkforums.com/attachments/f65/190532d1323440424-distance-scales-hand-shaper-engraving-2-600.jpg


The finished brass knob ready to use.

http://www.woodworkforums.com/attachments/f65/190533d1323440424-distance-scales-engraved-knob-600.jpg


A 30+ year old 96 tooth brass index wheel showing the stamping.

http://www.woodworkforums.com/attachments/f65/190534d1323440424-distance-scales-mk3-index-wheel-800.jpeg

[Bryan]

Mark, very tidy work. Thanks for posting.
Can I ask what the knob was for?

[Graziano]

Mark, very tidy work. Thanks for posting.
Can I ask what the knob was for?

Hi Bryan, it goes on a gemstone faceting machine:
http://www.woodworkforums.com/attachments/f65/190551d1323475425-distance-scales-xtra.jpg

[Anorak Bob]

Mark,

Thanks very much for going to the trouble to post the photos. The little "shaper" setup is neat. So far, the graduating I've done has been radial and axial and I've managed on the lathe. Linear will be a challenge.

BT

[Anorak Bob]

Hopefully of interest. I was impressed as "not excessively toxic." All the best with this one - as always look forward to hearing / seeing the final pics. Mark

Thanks for the scans Mark.:2tsup:

BT

[Graziano]

Mark,

Thanks very much for going to the trouble to post the photos. The little "shaper" setup is neat. So far, the graduating I've done has been radial and axial and I've managed on the lathe. Linear will be a challenge.

BT

I'd expect one of those cheap linear encoder readout units that look like they came off a digital caliper would do the trick, you could even work out the readings to make a vernier scale on a spreadsheet.