miken
Part of the e-furniture
Posts: 481
|
Post by miken on Jul 5, 2019 20:40:39 GMT
Ive recently received a new nib for my BM lining pen (after dropping it and bashing in the old one!). Ive been painting some buffer stocks and was quite pleased with how they turned out. First i had to make a thingy to hold the pen in the lathe toolpost. Its just a bit of flat bar with a m3 screw and a light spring. I drilled a 3.2mm dia hole through the handle of the pen. The pictures explain how its done. The end ring was done with a paint brush and thinned black paint as the work revolved slowly.10 rpm maybe. [img src=" ![]() oi67.tinypic.com/14t0jkj.jpg" style="max-width:100%;" src="http://oi65.tinypic.com/2cdbfi0.jpg"]     |
|
|
|
Post by cplmickey on Jul 5, 2019 21:12:00 GMT
Excellent result. Hope mine come out half as good as that - mind you they aren't as fancy!
|
|
|
|
Post by danlank on Jul 5, 2019 21:29:18 GMT
Stunning work matey!
|
|
|
|
Post by cnr6400 on Jul 5, 2019 21:43:05 GMT
Top notch lining! well done.
|
|
|
|
Post by Jim on Jul 5, 2019 22:09:49 GMT
Totally agree with the rest.
That is a very professional job of lining out, it looks perfect and complex. As the others have said 'Brilliant' Never having used one of these pens what is the consistency of the paint used?
Jim
|
|
|
|
Post by simplyloco on Jul 5, 2019 22:51:30 GMT
Totally agree with the rest.
That is a very professional job of lining out, it looks perfect and complex. As the others have said 'Brilliant' Never having used one of these pens what is the consistency of the paint used?
Jim
The instructions say that paint straight from the tin is fine, but 'add some lighter fluid' to reduce surface tension. It worked for me! John |
|
miken
Part of the e-furniture
Posts: 481
|
Post by miken on Jul 6, 2019 7:32:23 GMT
Totally agree with the rest.
That is a very professional job of lining out, it looks perfect and complex. As the others have said 'Brilliant' Never having used one of these pens what is the consistency of the paint used? Jim
The instructions say that paint straight from the tin is fine, but 'add some lighter fluid' to reduce surface tension. It worked for me! John Yes, I used lighter fluid. Clear instructions included with the pen. |
|
|
|
Post by Jim on Jul 6, 2019 7:41:50 GMT
Thanks for that information. I must do some experimenting with a lining pen I made from a converted Stabilo pen.
Jim
|
|
|
|
Post by 92220 on Jul 6, 2019 8:10:53 GMT
Really nice job Mike, and a clever idea for using the lining pen, in the lathe, to do the buffer stock lining.
Bob.
|
|
|
|
Post by ettingtonliam on Jul 6, 2019 9:32:17 GMT
Wonder if one of the CNC whiz kids can come up with a programme for the milling machine, so that with the pen in a spindle mounted holder, large flat surfaces such as tenders, cabs and tanks can be lined?
Beautiful work on the buffers by the way.
|
|
|
|
Post by Roger on Jul 6, 2019 10:15:15 GMT
Wonder if one of the CNC whiz kids can come up with a programme for the milling machine, so that with the pen in a spindle mounted holder, large flat surfaces such as tenders, cabs and tanks can be lined? Beautiful work on the buffers by the way. Lovely work, a clever solution with a cracking result. In answer to your question, yes, it's easy enough to create a tool path. The only issue is how flat the surface is. Some systems can track the surface with a probe, but mine would either need it to be flat or to somehow map the surface and create a path that rises and falls to match the part. It's certainly worth looking into for the surfaces that are nicely flat. |
|
|
|
Post by Deleted on Jul 6, 2019 10:30:28 GMT
I don't think using the pen on a CNC machine would work, well not with the pens available, as the paint flow varies and clogs at different rates depending on the ambient temperature. I think you'd need to develop a pen head with a constant smooth feed rather than relying on gravity, something like a plotter head perhaps. There are some very large plotter tables out there with variable height, could be used for something like tender side lining, however, add in lines close to soleplate/beading and rivet detail and things get much more complicated.....
Miken. love your painting, first-rate sir...
Pete
|
|
|
|
Post by 92220 on Jul 6, 2019 12:26:13 GMT
Wonder if one of the CNC whiz kids can come up with a programme for the milling machine, so that with the pen in a spindle mounted holder, large flat surfaces such as tenders, cabs and tanks can be lined? Beautiful work on the buffers by the way. Lovely work, a clever solution with a cracking result. In answer to your question, yes, it's easy enough to create a tool path. The only issue is how flat the surface is. Some systems can track the surface with a probe, but mine would either need it to be flat or to somehow map the surface and create a path that rises and falls to match the part. It's certainly worth looking into for the surfaces that are nicely flat. Hi Roger. I don't know how much vertical movement you have on a tool when it is setting itself up, but if the pen was spring loaded vertically, wouldn't that cope with any slight unevenness of the platework of say a tender side. It certainly sounds like a good way of getting a perfect lining job!! I would guess the main problem would be aligning the pen with the datum for the path......but I'm sure you would be able to come up with something workable!! Bob. |
|
|
|
Post by Roger on Jul 6, 2019 18:27:30 GMT
Lovely work, a clever solution with a cracking result. In answer to your question, yes, it's easy enough to create a tool path. The only issue is how flat the surface is. Some systems can track the surface with a probe, but mine would either need it to be flat or to somehow map the surface and create a path that rises and falls to match the part. It's certainly worth looking into for the surfaces that are nicely flat. Hi Roger. I don't know how much vertical movement you have on a tool when it is setting itself up, but if the pen was spring loaded vertically, wouldn't that cope with any slight unevenness of the platework of say a tender side. It certainly sounds like a good way of getting a perfect lining job!! I would guess the main problem would be aligning the pen with the datum for the path......but I'm sure you would be able to come up with something workable!! Bob. Hi Bob, You certainly could spring load the pen, but I don't know if that would be acceptable. I don't really know how these things work. Obviously anything resting on the work near the line would have to avoid smudging the line. |
|
uuu
Elder Statesman
your message here...
Posts: 2,816
|
Post by uuu on Jul 6, 2019 19:01:10 GMT
Rotring technical drawing pens have a tiny filament running up from the tip, which lifts a valve to control ink flow. This sounds like an attractive method, but might not work so well (or at all) with paint.
Wilf
|
|
|
|
Post by 92220 on Jul 7, 2019 8:15:32 GMT
Hi Wilf.
The Rotring pens won't flow paint unless it is thinned considerably, and that makes it unsuitable for lining. However, the Uno pens are better at paint flow and these led to the design of the Bob Moore lining pen, which works brilliantly.
Bob.
|
|
|
|
Post by 92220 on Jul 7, 2019 8:31:04 GMT
Hi Roger.
When I was thinking of a spring-loaded pen I was thinking the spring would be in line with the pen to just spring it onto the surface and take up undulations in height. As far as how they work....the pens have a little bowl to hold the ink/paint, and the nib is a hypodermic needle (no sharp point) of suitable diameter, with a fine wire through the bore. This causes the ink/paint to flow through by capillary action. The wire does not protrude from the nib but is also spring loaded to be able to be pushed down the tube to help get the flow going. A Bob Moore pen can, with the right paint viscosity, draw a line nearly 3 feet long, in one go. I think, if you can find a Uno pen of similar size, it would work the same.
Bob.
|
|
|
|
Post by Roger on Jul 7, 2019 14:50:39 GMT
Hi Roger. When I was thinking of a spring-loaded pen I was thinking the spring would be in line with the pen to just spring it onto the surface and take up undulations in height. As far as how they work....the pens have a little bowl to hold the ink/paint, and the nib is a hypodermic needle (no sharp point) of suitable diameter, with a fine wire through the bore. This causes the ink/paint to flow through by capillary action. The wire does not protrude from the nib but is also spring loaded to be able to be pushed down the tube to help get the flow going. A Bob Moore pen can, with the right paint viscosity, draw a line nearly 3 feet long, in one go. I think, if you can find a Uno pen of similar size, it would work the same. Bob. Hi Bob, Thanks for that explanation, I'm clipping that to me notes for future reference! |
|
|
|
Post by Deleted on Jul 7, 2019 18:23:25 GMT
Hi Bob
I don't think that the wire is intended for anything other than to clean the nib, I have no recollection of it being a requirement of it remaining in situ during painting. From my own experience, I find that the paint flows best when mixed with a small amount of lighter fluid, some mix it fully before putting the paint into the cup. Others, put the paint in the bowl first and apply a drop or two of lighter fluid and then draw the nib along a piece of kitchen towel to get the paint flowing. I prefer to pull the nib along my finger to start things off, if the paint is still stubborn I'll blow into the bowl which will form a blob of paint on the nib which is removed with my finger, the paint should now flow evenly. A lot depends on the paint (IMHO, only use enamels) and the temperature of the room you are working in, too hot and the nib will block to easily.
regards
Pete
|
|
barlowworks
Statesman
Now finished my other projects, Britannia here I come
Posts: 874 
|
Post by barlowworks on Jul 7, 2019 22:00:24 GMT
Also make sure the paint you are lining on is really cured or it will mark the surface and block up the tubular nib.
Mike
|
|
