making alignment marks on plywood

[crowhurst]

Windows 10, Qcad 3.26.4
I am designing a kayak in England for a friend. The kayak will be transported by air in kit form, so the hull panels will have multiple joins. I need to make surface dots for placing pins into the 3 mm plywood for alignment with a thread during construction in the USA. How can I make an accurate tiny but visible mark that does not pierce the plywood?
Many thanks, from Nick.

[jcolo59]

Hi Crowhurst,

I sounds like a stitch and glue project. Did you layout the panel templates in QCAD? You can add the stitch points to the templates as small dots or circles.

With the template on the panel you should be able to push a pin or awl through each dot to leave a small depression. It is a bit time consuming but you could just as easily send a copy of the template with the panels and let your friend do the hard part.

Regards

[crowhurst]

jcolo, thanks for the idea, but there are no templates. It's all in my head and on Qcad. If necessary I can place a 1 mm diameter CNC drill hole at each point, but very small holes are notoriously tricky to seal against water. The film just parts, and the hole emerges. Yes, it's S & G: cnckayaks.com
Nick.

[Husky]

The parts are cut by CNC? Engrave a line or small circle - no need to penetrate the material.

[crowhurst]

Husky, thank you. I have no knowledge of engraving on QCAD, other than the search facility in "Help" stating ."Line fonts are also often used for engraving". I'd be grateful if you could point me in the right direction to place a 1mm diameter circle engraving or a single visible point on 3mm plywood which will be cut from my .dxf file on a CNC machine. Many thanks,
Nick.

[Husky]

Husky, thank you. I have no knowledge of engraving on QCAD, other than the search facility in "Help" stating ."Line fonts are also often used for engraving". I'd be grateful if you could point me in the right direction to place a 1mm diameter circle engraving or a single visible point on 3mm plywood which will be cut from my .dxf file on a CNC machine. Many thanks,
Nick.

Nick, my problem is that I don't know which typ of CNC machine is used. Is it a laser or a milling CNC? However - to control a CNC you need the G-Code. The G-Code is most likely created with a CAM program (you could also write it from hand). This said - will this code be programmed by yourself or do you have a service provider who will do that for you?

In short: Basic is still the Qcad dxf/dwg drawing. A CAM program will apply to each entity on the drawing a path which will tell the CNC to move inside, on or outside of an entity. Another info is attached to this path which tells the CNC how deep to cut - all the way through or only a certain depth. A very slightly depth with an engraving bit would then be called engraving.

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In the case you don't have engraving bits - you could do a grooving. That means you use a normal shaped bit and tells the CNC to dive only a fraction into the material. Circle or line? Doesn't matters. That would work in your case too.

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In the case you have only a drill bit - tell the CNC only to drill 0,25 mm (?) into the material.

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In the case you have a laser - "engraving" is done with reduced laser power which will leave a black line (burn mark) on the material.

BTW: Your kayak's are beautiful!

[crowhurst]

Husky, many thanks for making such a detailed reply. I don’t know which shop will do the cutting. Your description has convinced me that I will simply use “DRAW > CIRCLE 1mm diameter, and deal with the leakage issue with glass and epoxy tabs on the inside of the plywood.
I’m delighted that you admire the shapes of the kayaks. Your QCAD has played a vital and central role in the success of the project, which has taken an array of modern technologies and amalgamated them to supply, free-of-charge, plans and Build Manuals to build 32 pound sea kayaks that are half the weight of many commercially available fibreglass sea kayaks, and at about one eighth of the cost. The plans are issued under a Creative Commons Licence, which enables anyone to build the kayaks, to sell them and to adapt them, all totally free of charge. The only requirement is that the cnckayaks.com website is stated as the source of the plans.
Those technologies are: top quality marine plywood, epoxy resins, glass fibre fabric, CAD technology, QCAD, the internet, PDF, email, and cloud storage. None of these technologies existed a few decades ago. You can see how your superb QCAD has been central to the existence of the project since its inception 7 years ago. So well done, and thank you.
So far 8,500 copies of the plans have been downloaded world-wide, and 369 people from 53 countries have been kind enough to send me photos and descriptions of their kayaks. Some of them are pictured in our Galleries at www.cnckayaks.com
Many thanks for all your efforts.
Nick

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[J-J]

Hi Nick,
Your kayaks are very tempting, especially since I live near Marseille, and the bay is quite nice for those boats!

[crowhurst]

J-J, very soon I will be adding a French translation of the Build Manual to the free plans download. I can imagine paddling happily past Les Calanques.
Nick.

[J-J]

I read more in English than French, but if you need proof reading, I'll be happy to help

[crowhurst]

JJ, I've had assistance with proof-reading from the French sea kayaking forum, but thank you for the offer.
Nick.