HMS Winchelsea 1764 by John Murray - 1:48

[John Murray]

Hi Everyone. I bought the plans and downloaded them several weeks ago. I was contemplating having Chuck send the starter kit to me in Australia. It seemed the easier way. However, I have chanced up a community makers space a few miles away which provides access to laser cutters, and woodworking machinery that I don't have.

 

I bought a block of Cherry a while ago and thought I would see if they could assist with sizing it into 3 x sections by ripping the 1 1/4" slab on a bandsaw. The bandsaw was waiting a new blade so they used a table saw. I sized the slices to 1/4" on their thicknesser.

 

I then used 2 of the pdfs I had for the stem to test out their laser cutter. It has a bed size of 1300mm x 900mm.  My little piece was accommodated with ease. 

One question I have though regards the bulkheads and keel pieces. They are 1/4" ply. That size is problematic in Australia being a metric country. I can source 6mm or with some difficulty 6.5mm plywood. Both are fine? grades for exposed faces in furniture production. 1/4" though is 6.35mm. If I substitute the 6mm OR 6.5mm ply, what issues could be expected further down the build? Thoughts or workarounds?

 

Edited May 25 by John Murray

[Chuck]

6mm is fine.  In fact I believe my bulkhead sets are 6mm

[glbarlow]

An ambitious beginning, looking forward to your progress. 

[John Murray]

I spent some time gluing up the parts. 

One thing I noticed whilst I was watching the laser cut was that around 2 thirds of the lines would cut with a single pass of the laser. These resulted in nice clean cuts. However, the remaining lines each had up to 10 or more passes which resulted in scorching and small holes from I assume reflections of the aluminium grid it was resting on as the beam repeatedly passed over the same path. 

As can be seen in the two images, some of the joints are spot on. However, there were other joints where the wood had been scorched away from repeated passes of the laser. This resulted in gaps in some of the joints. I have highlighted problem areas in the two images. The scorch mark are obvious in the images I posted above. That is the top side view of the board. The underside was much worse. I suspect the person operating the laser (I wasn't inducted) did not know how to correctly setup for the cherry. I did not notice a setting in the software for wood except MDF or Plywood.

I shall be modifying my approach to this piece. I used 1 1/4" cherry and after cleaning the scorch marks and correcting a very slight bow I induced from the glueup, To glue up I will be using pins and a board to hold the pieces flat whilst drying. This attempt though I did not. (I used my Proxxon Planer then Thicknesser to flatten and clean up both sides.) I ended up with a flat stem at 210 thou instead of 250 thou. 

It shall be remade and I am considering changing from Cherry to another wood that I can source in Australia. Poplar or Huon Pine. 

I have also attached an image of two other laser cuts I made on the same wood panel. This show the underside though with the scorching. Unfortunately I did not get an image of the stem panel underside.
 

Edited May 28 by John Murray
Added an image.

[FrankWouts]

First of all welcome to the Winchelsea build group John. Very nice to see another Winchelsea being started!

Aren't you afraid that further down the line, things will not fit 100% when experimenting with letting your pieces cut by various laser cutting shops?

How much off are the two different sets of pieces you already have now compared to each other?
Apart from the few cut away corners you showed, are the pieces the same size and consistent in shape, etcetera?
I wish you lots success and most of all much fun building your Winchelsea!
Frank.

Edited June 6 by FrankWouts
typos

[John Murray]

12 hours ago, FrankWouts said:

First of all welcome to the WInchelsea build group John. Very nice to see another Winchelsea being started!

Aren't you afraid that further down the line, things will not fit 100% when experimenting with letting your pieces cut by various laser cutting shops?

How much are the two different sets of pieces you already have now compare to each other?
Apart from the few cut away corners you showed, are the pieces the same size and consistent in shape, etcetera?
I wish you lots success and most of all much fun building your Winchelsea!
Frank.

G'day Frank,

Thank you for that. I have joined a makers space nearby that has woodworking, metalworking, 3d printing, and 2 laser cutters in the space that I can use.

The two laser cutters are
     1 ) Trotec Q500 running Ruby with a bed size of 1,300mm x 900mm and a 120 watt laser.
     2) Thunder Laser Nova 35 running Lightburn with a bed size of 900mm x 600mm and an 80 watt laser.

I have used both. I found the Nova 35 running Lightburn much easier to use due to the Lightburn software. I need to be inducted though in 2 weeks time before I can do it myself. Currently, I need someone over my shoulder supervising.

My plan is to use Poplar 900mm x 600mm 6mm ply that I can source locally for the bulkheads and other things requiring 6mm ply. For the 1/4" stem etc I plan to use either Poplar or Huon pine slabs that I can rip to thinner boards with their bandsaw. Once that is done, I will run each boards large face flat on the planer. Once they are all done, I shall then flip them all and run each board through the thicknesser to get to 1/4" thickness.

 

I have downloaded the full Creative suite. I split the bulkheads into individual pdfs. Then, in Illustrator I created 2 documents sized 900mm x 600mm.
The first document has the 3 keel pieces and the first 14 bulkheads all fitted into the document. The 2nd document has the remaining bulkheads. 
In Chapter 1, all of the 1/4" pieces were placed into a new document sized to minimise the waste of the Polar or Huon.

The MDF 6mm cuts were ok, some slight scorching on the rear. Having talked to a few users in the makerspace I get the feeling they use just the material defaults in Lightburn and are happy with the results. Me though, I have looked into the software and there is a lot of tweaking that can finetune the laser to the particular material and thickness.

Once I am inducted, I shall do some calibration tests for the 1"4 Huon or Poplar and 6mm Poplar ply so that I will get good, consistent cuts by the laser. I will also be checking to see if the laser is set to allow for the kerf of the laser. 

Once that is done, I will then run the final 1/4" and 6mm pieces through the machine. 

Everything I am doing so far is to build my experience with the software and to eliminate as much waste as I can. I will do things myself only to eliminate the issue you raised or buy things I need that I cannot manufacture myself off Chuck. . 

Edited June 5 by John Murray
Added clarity