rapidograph & isograph pens feature

What Is The Difference Between Rapidograph And Isograph Pens

What Are Rotring Rapidograph And Isograph Pens?

Rotring Rapidograph and Isograph Pens are steel nibbed Technical Pens for drawing on tracing paper, vellum and lineboard.  Both Rapidograph and Isograph Pens have been used for years by draughtsmen and engineers to make lines of a constant width. When enlarging or reducing a technical plan drawn with a Rapidograph or Isograph Pen, the lines will stay to scale.

Rotring’s winning formula of technical precision and range has ensured their continued appeal with today’s architects, students, designers, illustrators and artists.

Gregoire Lepeigneux is an artist and illustrator based in Paris. He says:

“The Isograph 0.1 is a technical pen which helps me to produce exactly what I want. Its deep black ink, its fine line width and its fluidity allows me to work in the same way as I would work on an engraving. I can perfect my style thanks to it. It is the perfect pen for me.”

 Artist Uses Rotring Rapidograph And Isograph Pens
Gregoire Lepeigneux sketches with an Isograph 0.1 Pen

What Is The Difference Between Rapidograph And Isograph Pens?

The Rapidograph Pen uses Rotring’s innovative capillary cartridge including the ink helix.  Each time you change the cartridge you get a new clean ink helix and pressure equalisation system.  You never have to clean the ink helix!  This makes the Rapidograph Pen the more popular of the two as it is a lot less messy and is less likely to get clogged up.

The extra-large volume of the ink helix and the location of the ventilation opening allows for improved temperature stability.  The ink can therefore be used right down to the last drop!


Rotring Rapidograph Pen


The Isograph Pen features a refillable ink reservoir.  The patented push-on sleeve allows for easy access to and fast cleaning of the ink helix, even when the reservoir is full.  The Isograph is ideal for frequent drawing using bottled inks. This means that your colour range is more versatile with an Isograph Pen as you refill it yourself.

Both the Rapidograph and Isograph Pens come in 13 different line widths and feature chrome plated thin nibs allowing you to create highly detailed work.


Rotring Isograph Pen

What Ink Do I Use In Rapidograph And Isograph Pens

Rotring’s technical pen ink is suitable for use on tracing paper, vellum, drawing paper and lineboard.  It is lightfast, fast-drying, waterproof and smudge free once dry.  The high density of the pigment gives it high opacity and the sharpness and adhesion of the line is superior.

This ink is often used by tattoo artists for tracing the work onto the skin and in their initial sketches.  Rotring’s technical ink gives you the densest, blackest line on the market.

The Rotring technical pen ink cannot be erased with Rotring pencil erasers B20 or B30. The coloured inks can be inter-mixed with each other.


                        Rotring Isograph Ink              Rotring Rapidograph Ink Cartridge


Rapidograph Ink Cartridges are available in black, blue and red ink. You get 3 replacement ink cartridges in a pack.

Isograph Ink is available in 23ml Bottles in black, blue, red and white ink. Black ink is also available in a 250ml bottle.

What Nib Sizes Are Available For The Rapidograph & Isograph Pens?

Both the Rapidograph and Isograph Pens are available in precision line widths from 0.10 to 1.0mm.  This gives you a wide range to choose from whether requiring a continuous width of line for technical drawing or a greater choice for tonal and shading work.

Replacement Rapidograph Nibs and Isograph Nibs are available in the following sizes: 0.10, 0.13, 0.18, 0.20, 0.25, 0.30, 0.35, 0.40, 0.50, 0.70, 0.80 & 1.00.

Nibs for Rapidograph and Isograph Pens are long lasting and easy to replace, but the finer the nib the more quickly it tends to wear down.

Helpful Tips For Maintaining Rapidograph And Isograph Pen Nibs:

If you feel the nib is slightly blocked just leave in warm water with a little fairy liquid overnight.  Make sure that the nib is not touching the bottom of a surface as this could damage it.  If this doesn’t do the trick then ask in store for Rotring Cleaner sachets.

Are Rapidograph And Isograph Pens Available In Sets?

We stock Rapidograph And Isograph Pens in College Sets.  These sets are ideal if you need a range of pen sizes or if you are about to start an Architecture or Interior Design Course. They offer a great saving on the single pens!

The Rapidograph College Set contains:

3 Rapidograph Pens (0.25, 0.35, 0.5) , 1 rotring Tikky Pencil 0.5, 12 hi-polymer HB leads, 1 B20 eraser, 3 pen stands, 3 black ink cartridges & 1 compass technical pen attachment.

The Isograph College Set contains:

3 Isograph Pens (0.25,0.35,0.5), 1 rotring Tikky Pencil 0.5, 12 hi-polymer HB leads, 1 B20 eraser, 1 bottle of black ink 23ml & 1 compass technical pen attachment.


Drawing With Rapidograph And Isograph Pens


So, for precision in your artwork and designs, make sure that you use Rotring Rapidograph and Isograph Pens.


Are you starting an architecture or design course?  Buy your Rapidograph and Isograph Pens along with other technical Art Supplies from Pullingers Art Shop.

Show us your artwork using Rapidograph and Isograph Pens!

37 thoughts on “What Is The Difference Between Rapidograph And Isograph Pens

  1. Hi there. I found the above useful, but what I was really looking for was spare parts to restore, ‘ones the kids had found….’ specifically Rotring Variant pens. Is the Iso range the replacement for Variant?

    Hope you can help,

    Many thanks

    Eric Knight

  2. Hi, I have a couple of questions, what pen would I need to get the finest possible line ?
    How dense is the white ink?
    Many thanks,


  3. Hi Pullingers,

    Your article above was informative and easy to digest. I have an old Rotring 0.35 (over 20 years old) that says “Rotring Rapidograph ISO” – does this mean it’s a combination of both..that I can either refill the ink or buy replacement cartridges?

    I hadn’t used it in many years. I took it out the other day, soaked in warm water and a bit of dishwashing liquid for two days. The ink still doesn’t flow out smoothly. After a few strokes, it dries up and I have shake it up. Any suggestions?


    1. Hi Connie,
      The Rotring models have changed during the last 20 years (approx) and so there is a possibility that yours may not be compatible with the current capillary cartridges. If your pen has an empty reservoir inside, you could use a bottle of Rotring ink to fill it, but without seeing the pen itself it is difficult to know for sure.
      As for cleaning the nib, we would recommend using Rotring Cleaning solution to help get the ink flowing through the nib again. The instructions for use should be included in the box.
      Let us know if you need any more help with this,
      Thanks for your question,

  4. Hello,

    I have been using your pens for many years, they are fantastic for the work i do (i am an illustrator.)
    What pen could i use though to cover large areas of black? I am looking for a pen that uses the same ink that the rapidograph uses so that the whole picture remains consistent.
    Previously I have bought your bottled ink and painted it on, but would prefer to use dry media like markers if you have or know of any.

    Thanks for your help!


    1. Hi Tom,

      Great to hear that you are enjoying using the Rotring pens! I believe that Rotring ink may work in one of our empty Paint Markers, such as the Schmincke Aerocolor Liners or the Molotow ONE4ALL Empty Paint Pens as they can be filled with most inks, but they may dry out quickly due to the solvent in the ink. If you do decide to try this, please feel free to give us feedback on how it went, we would love to hear more about this technique!
      I hope this information helps, you can find links to both of the products I mentioned below.


      Kind Regards,

  5. Hello Folks, your site is great,

    . Looking to purchase a College set of rapidogra[h pens, for a family member who would like to use them for lettering and also sketching/drawing? Which set would you recommend and also, if there is an extra pen along with a college set, what would complete his needs? i.e offering him the best combination of lettering/printing nibs and sketching nibs?


    1. Hi Mike,

      Yes there are a couple of different College sets available from Rotring at the moment, but the Rapidograph one would probably be better suited to your needs as you mentioned before. The set comes with 3x Rotring Rapidograph Pens in 0.25, 0.35 & 0.5, 1x 0.5 Tikky Pencil, 1x pack of 12 HB leads, 3 cartridges and a range of other accessories. You can find this set at the link below.

      If you were looking for another pen to perhaps go with the set, i would recommend a thicker pen, perhaps around a 0.8 just to give your family member more choice if needed. You can have a look at the range of Rapidograph pens that we offer here- http://www.pullingers.com/c/1864/pen-supplies-and-markers/technical-drawing-pens/rotring-rapidograph-technical-pen/

      Kind regards,

  6. Heey
    I’m planning to buy a radiograph pen.
    I want to buy ink helixes to. Hete I can chose between radiograph ink and radiograph ink “F”. What does the F mean?
    The one without the F is soldout.

    Thanks 🙂

  7. Just about to buy (I think) a Rapidograph pen 2.0mm because I want the largest tip but can that be possible? You don’t suggest anything larger than 1.0mm?

    I would actually like to use my own coloured inks – various….so do you suggest Isograph 2.00mm? Is there such a thing?

  8. Hi Emma,
    my old Rotring rapidograph (.1) is skipping. It was so reliable for a long long time. I think skipping suggests it’s not damaged? but rather clogged? Which would suggest i need to clean it better, I assume and that may mean an ultrasonic cleaner? or does skpping suggest it’s damaged?
    It is an older pen, and I do not think i can get a new nib for it this size. I may have to buy a new pen?

    1. Hi Jo
      Have you tried using Rotring Concentrated Cleaner? This would be the only thing I would recommend using to flush through your pen, and if it is a dried ink problem, this may help to rectify it. I would suggest giving that a try first before considering buying a new pen.
      Thanks for your question,
      Kind regards,

  9. Hi, I’m just in the process of cleaning out and getting my old college isograph and rapidograph rotring pens working again. The 1.0 ‘rattles’ nicely, and when testing it with water it flows through really well, but when testing with (very old) rotring ink, it skips. Is the the old ink, or is the nib permanently damaged?

    1. Hi Rebecca,
      It could be that your old ink is no longer usable, or it is a possibility that your nib may be damaged. I would advise using some new Rotring ink in your pen to see if that works better, if not you may have to purchase a new nib if it is a newer model.
      Thanks for your query,
      Kind regards,

    1. Hello Ken,
      I would image that non-waterproof inks would be OK in your pen, however we would always recommend sticking to the manufacturers own products to really get the best out of your pens.
      Thanks for your question,
      Kind regards,

  10. Can you possibly help.
    my son needs a 0.18mm nib rotring pen for his geology. He has to have black, red and green ink. Does he need to purchase 3 pens?

    1. Hi Jane

      The Rotring Rapidograph would be best suited to him, as it is cartridge based so is easier to refill with different inks. I would recommend having different nibs for each colour, as otherwise you have to flush the nib through each time you want to change colour. Unfortunately, Rotring do not do green ink, so he may need a different style pen for this part of his work.
      You can find our Rotring Rapidograph Pens here: https://www.pullingers.com/c/350/rotring-rapidograph-technical-pen and the replacement nibs for them here: https://www.pullingers.com/c/352/rotring-rapidograph-pen-nib
      Thanks for your question,
      Kind Regards,

  11. Hi,
    I have tried using Rapidograph pens several times in the past but never could keep them working properly. I constantly had the problem of cartridges leaking inside the barrel or getting endless blobs of ink forming on the tip of the nib when I was trying to write or draw. This made using the pens almost useless to me. Is this a common problem or am I doing something wrong?

  12. Hi i have a new isograph for Christmas hve filled with rotring ink but the pen dose not seem to want to work i have an extra nib and still have same problem could you please help

  13. Hi i have a new isograph for Christmas hve filled with rotring ink but the pen dose not seem to want to work i have an extra nib and still have same problem could you please help

  14. Problems getting the ink in my ISO graph pen to flow out I have soaked it in warm water cleaned it and let it dry completely I just can’t figure out what else to do to get the ink to flow out the tip. I only got this pen a month ago I don’t think it should need replacing of any parts. Any suggestions is appreciated.

  15. Hello, I’ve got a question about how long can I keep the ink in the isograph without cleaning? I don’t want to damage it but sometimes I am too lazy to clean just after my work.. I’m a begginer.
    Thanks in advance!

  16. I have just received a present of a new Rotring Rapidograph set but with all the pens I am having difficulty getting ink through from the cartridge to the nib. Have i missed something?

  17. Do they sell the refillable reservoirs for Isoographs separately? You can buy a replacement nib but not apparently the reservoir to go with it.

  18. I have several old Rotring pens, clogged with dried Rotring black ink. I can’t dismantle them, so what is the best way to clean them please?

  19. Although I trained as a draughtsman many years ago, I am now retired and would like to know, given the expense of Rotring black ink, could I use a black
    Quink ink instead without damaging the pen. Any work is completely non-commercial and simply for my own pleasure.

Leave a Reply

Your email address will not be published. Required fields are marked *