Deck Plank Caulking Mock-up
by chhbmd (Charlie)

A while back I had ask for caulking techniques and received several very good ideas. Which do I use? I decided to test them all and found that they were all good. However some techniques are more labor or skill intense. A picture of my deck plank caulking mock-up is included with this article.

Following the test sections left to right there were five different techniques used and they are: paper, pencil, thread, grout and paint. I used the same thickness plank decking, as I will on my current ship model and that is 0.5 x 4 mm.


The different methods were: (Left to right)

1. Paper: Black construction paper was used for this sample. The planks were stacked together and clamped creating a wider flat edge surface then .5 mm. Glue was applied to the construction paper then the planking stack was pressed onto the glued area. Once the glue was dried the planks were separated on a cutting board using an X-Acto knife with a sharp pointed blade. This was generally acceptable with a few planks having the paper partially separating from the plank; this may have been from insufficient glue on the paper or incorrectly separating the planks from the temporary stank. Small slivers of paper were used for the end plank joint. To finish the deck section the paper extending above the plank was carefully shaved off then the deck was scraped finished.

My evaluation for this method is acceptable but using a dark gray or lighter colored paper. The thickness of the paper seem to be to thick producing a wide dark caulk joint on the deck and definitely it would be better on thicker deck planking.

2. Pencil: This method is a relatively easy way to show the caulking joints. It was noted that the full effect of pencil joints are not fully noticeable until the finishing stage. The pencil used was a 2mm drafting pencil with HB leads allowing the point to become slightly blunted. The first few planks glued down were then struck with the pencil. Not a very good method so I made a jig that would support the plank and the pencil could be drawn along the edge via a grove in the jig corresponding to the edge of the plank. This made striking the edges and the ends without slipping and drawing a line across the deck planks. The messy mistake made on this trial deck was sanding the deck. The sanding method mixed graphite with the sanding dust resulting in black deposits in low areas of the wood grain. Scraping should have been used to reduce the amount of lead raised during finishing. This would have prevented wood indentations being filled with dark residue.

Bottom line this is a good method to use realizing some of the pitfalls.

3. Thread: The thread procedure was used on my project the C.W. Morgan deck and with a somewhat acceptable result. After reading up on the subject one of the major complaints of this method is that it produces a 3-dimensional look on the deck. Not being savvy on model ship construction I found this was acceptable but after making the sample and a closer examination was made the complaint has validity. Looking straight down upon the deck it is a clean look however a close examination on an angle the plank joints are noticeable. Being a little critical, I lightly pulled my thumbnail across the deck sample and the planks joints were very pronounce in comparison to the other methods used in the sample project. Would I use this method again, probably because I have to be happy with the final project?

Will I use this method on my present model this time? I doubt it because I want to see a different method result.

4. Grout: A very interesting concept of which I first doubted any good result however much can be gained by this method. The complete planking was laid and glued without any consideration of the joints showing a caulk line. Returning to the deck after the glue had dried the joints was struck with a regular household razor knife with a dull blade. The blade used was pulled, with moderate pressure, along each joint. Here was an opportunity to simulate the treenails without actually installing them. After all of the joints had been drawn, with the knife, a No. 72 drill bit was used at each treenail location, a point from a drafting compass was used to pre-punch each location before drilling. Now that all the joints have been struck and the treenail locations had been drill the sample is ready for the grout. Wall tile grout was suggested because of low sand content. The problem here was finding a charcoal colored grout. I did find in a craft store charcoal colored mosaic tile grout. Nothing beats a try but a failure; the mosaic grout was used. The mixture was made very thick and squeegee across the joints and treenail locations. Before the grout had an opportunity to setup the deck was scraped. After completing the scraping operation the treenails and joint locations turned out very nice however any impressions in the wood also had grout in it.

This method would be very good using a harder wood to reduce the dark marks on the planks.

5. Paint: This method setup is identical to the grout procedure. The end results are very similar as well as any pitfalls. The greatest disagreeable function of this method is that the paint must be thick, removed immediately and messy.

Skill is necessary to obtain a good result using paint, a skill that I do not possess.


Whichever procedure is chosen I feel that the first and foremost consideration is “what do you like for the finished product.”
chhbmd (Charlie)