A Port Dredger 1750 by Greg Davis - FINISHED - Scale 1:36

[Ainars]

I have to agree with the others, looks amazing.

[Greg Davis]

Today I made it to having the big wheel timbers installed. After doing so, I couldn't help but 'mock-up' the vessels configuration with the wheels!

 

You can see in the second picture that I have completed planking the small wheel. The small wheel will now get about 200 fasteners thru the planking and steps. Then the excess material on the steps will be trimmed and it shall be done. Repeat for big wheel coming as well,

[steamschooner]

Look'n real good, the number of fasteners gives it that special look.

[James G]

Looks so good, Greg!

[druxey]

Impressive, even at this stage of construction!

[Jim Lad]

Now that's an impressive looking bit of construction, Grag.

 

John

[Greg Davis]

All the fasteners for the big wheel timbers have been added. I've lined up and clamped the two rim structures with 18 mm spacers between the rims. The first couple of steps have been attached - there are 60 steps needed in this wheel, nearly twice as many as in the small wheel.

[Greg Davis]

Since last post, I have been skipping around a bit and getting various tasks completed and/or worked on. I also got to take one of my grandsons down to the Wisconsin Maritime Museum yesterday. While the WWII submarine Cobia was the main reason he wanted to go, he does seem to be getting more and more interested and knowledgeable about the model ships displayed there - I harbor a hope that one day we build a ship together! The museum is in Manitowoc, Wisconsin - a city of about 30,000 and with a strong heritage of ship building. 

 

All of the steps are in the big wheel and I am preparing (bending) planking material for that wheel now.

 

The two big davits are shaped and ready for some metal work. All the bollards have gotten their final shaping. The 12 knees that support the pillars at deck level are finished and installed along with the appropriate fasteners. Similarly the two sets of bits and knees are permanently connected to the vessel. 

The last thing I did today was to cement the superstructure unit to the pillars. The davits are just sitting on the structure for the pic.

 

 

[Greg Davis]

I wanted to share how I decided to make the davits. First of all, according to the monograph, the davits can be constructed in two different ways. One way is to make each davit out of a single piece of wood; the second is to make it out of three pieces - one central piece and two sides. The model presented in the monograph has davits built in three pieces; whereas I've seen the davits made in one piece presented in online build logs. I chose to make each davit out of one piece of wood. After I made this choice, I formulated several orders of operations in which to fabricate them. This is what I finally settled on. I don't know if it is the most efficient way to do the job, but it did seem to work well for me. The first attempt was a fail, but then I got the two I needed on the next tries.

 

I started by rubber cementing profiles of the davit to a length of wood 13.3 mm square in cross section. Note the center axis of the top/bottom profile is centered on the blank. 

I then milled the top profile. Having the top/bottom profile centered let me mill this portion perpendicular to the blank. Here I have started to smooth the curved region, but you can still see the horizontal lines left as steps from each pass of the milling process.

Next the bottom slot, where the davit locks on the superstructure was milled - note this is at an angle and there are specific left and right davits.

I then milled the two sides, the last milling operation. 

Using a scroll saw, the front space was opened up, after which the front length was shortened and then finished on a disk sander.

The back length was then adjusted so the davit fit correctly on the supperstucture.

Now it was time to remove some material in the middle to provide passage for the scoop chains. First I marked and sawed boundaries for the region to be removed.

The unnecessary material was mostly removed with a small chisel.

 

And the final shape of this inner region was developed using a sanding stick.

 

[Jim Lad]

The delightful work continues, Greg!

 

John

[James G]

Very nice fabrication strategy, Greg! The Byrnes table saw is the best for those angle cuts. What model of mill do you have? I’m currently doing a bit of window shopping for one.

[Greg Davis]

The mill is the model 5400 12" manual mill made by Sherline. I bought it (and one of their lathes) in 2012 and have not had many issues over the years. I have used the mill much more than the lathe. In hindsight, being enamored with Ancre publications, I now wish that I would have purchased the machines having metric scales instead of inches. I spend a good deal of time doing unit conversions! 

 

About 4 years ago, I committed a huge power tool no-no with the mill. My eyesight is not great, so when I use the mill I typically take my glasses off to better see what I am doing. My hair was long at the time and I did not have it tied back / contained at all when I was working and yes, my hair got caught in the belt drive. I was so lucky that this is a hobby mill instead of a larger mill. Even so, the Sherline had plenty of power to pull me to the machine before I could flip off the switch. In this very short time period a good size chunk of hair was pulled out at the roots. It was a dumb move on my part as I am well aware of the hazards and try my best to maintain a high level of safety; but this one time I had rushed, didn't think, and clearly payed the price.

[druxey]

Ow! Painful. Glad it wasn't worse though, Greg. At least you had the presence of mind to hit the switch. These things can bite....

[Greg Davis]

This evening I finished adding the three slanted pillars at the rear. Then I had time to make and install the mooring cleats that affix to the last superstructure cross-bar.

If I understand the monograph correctly, one way the dredger can be held in place during dredging operations is through the use of four anchors. Two in the front and two in back. The front two would have their anchor cables bound to the fore bit as expected; the anchors being set at angles radiating away from the vessel. Much like the small illustration on the cover of the monograph.

 

The aft two anchors also would have their cables connected to the bitts; however, they would not radiate like in the illustration as they would then foul the operation of the scoops. Instead the cables would go up and over the last cross-bar (between the cleats) and would then drop down into the water in such away that they would not foul the dredging process. The mid slanted pillar helps support the added strain from this method of mooring the vessel. Later, steps will be added to this pillar - a means for crew members to manage the mooring lines.

[Jim Lad]

She's really coming along nicely, Greg.

 

John

[James G]

Thanks, Greg for the feedback on your mill. I’m so glad you were ok after your mishap! It’s amazing how an accident can happen if we let down our guard for just a second. I try to be extra careful when I use tools like my Byrnes table saw. Call me paranoid. I’ve heard too many horror stories and don’t want to become a statistic myself. No doubt we have to respect many of the tools we use in our hobby. Your dredger continues to look beautiful. So fun to watch your progress!

[Greg Davis]

I keep on feeling stupid for making that mistake, it's not like I don't know of the dangers - unfortunately, I have had family and acquaintances that have lost fingers to table saws and planers. 

[druxey]

Don't feel too 'stupid', Greg; the story is an excellent cautionary one to your readers here. You may have saved a finger or two by posting it.

[Greg Davis]

On to a better subject!

 

Today I spent time fabricating components that will support the scoop guides. Here are the parts before installation on the dredger. I connected the smaller roller pin supports onto the external guide beam before drilling holes for the pins. I saw no other reasonable way to have half the hole half above (and half below) the joint.

 

The external guides / beams were then installed. This was easy because the notches placed everything into the right place. I then went to install the inside guides. Note that they come in two sizes with the smaller ones forward; also the smaller ones are not symmetrical, there is a front and a back to these. I set these four guides onto the superstructure to check their fit and at first thought I had done something radically wrong as they looked to be sitting way too low. But then I looked through the holes from one side and was pretty sure I could see through all four. To confirm, I grabbed a piece of stiff wire and passed it thru all four - and yes, all was as it should be! I then use the wire to aid in gluing the inner guides in place. I threaded the wire in place, slid an inside guide into the open space between the superstructure and the exterior guide, spun it over to apply glue, spun it back, and set it in place. Repeat 3 more times and all done.

Later, hourglass shaped rollers will be turned to fit between the guides, as well as the pins that keep them in place.

[druxey]

Making very nice progress, Greg.

[Greg Davis]

Over the weekend, guardrails and foot boards were added to the superstructure pillars. Also, I finished the last two knees - the ones that fit onto the slanted pillars. For some reason, these knees presented a great deal of difficulty for me to get all the angles right. Quite a few attempts were made before I was able to make a pair that I was willing to attach to the model.

Today I began work on the wheel bearings. The big wheel bearings are being done first because they looked to be less complicated than the small wheel bearings. The main challenge being that the bearings have footprints that match the curve in the superstructure carling (i.e., the bases are not rectangular) and the required shape looks to be more pronounced for the small wheel bearings than that for the big wheel bearings. Also, because of the carling / base shape, the recesses in the bearings need to be milled at an angle so that the wheel axles embed properly. 

 

 

[Jim Lad]

Looking more and more betterest every day, Greg! 

 

John

[Greg Davis]

The wheel bearings are complete and firmly attached. Cleats are in place as well - not too easy to see, but they are on the inside of pillars 1,2, 5, and 6.

The two wheel axles in these pics are now classified as 'practice pieces' - they were fails, better ones will be made! However, they are being used to check wheel alignment, etc. Looks like everything is going to be were it belongs.

 

 

[Tobias]

Hi Greg, this all looks fantastic, really great work.

[Greg Davis]

Thank you very much!

 

 

[Greg Davis]

Over the past few days I did make a new set of axles. These will be keepers!

 

Later the big wheel axle will get some doublings to help support the scoop chains.

Above you can also see that I am adding the fasteners to the scoop guide components. I've been doing a lot of fasteners lately - guard rails, cleats, foot boards, ... Still quite a few to go on the superstructure, but progress is being made.

 

Here is the new small wheel axle.

I've been doing other odds and ends as well; for example all of the small wheel steps have been made flush with the rims and some metal work has been done on the davits.

[Jim Lad]

Very impressive, Greg!

 

John

[Greg Davis]

Since my last post, I have added all of the superstructure fasteners and metalwork. Here is the last picture I took before oiling the deck and superstructure:

Today I spent nearly 4 hours swabbing linseed oil onto the deck and upper works. I think it is looking pretty nice, and am really looking forward to seeing it with wheels and scoops.

In a few days, when completely dry, I can think about adding 6 ring bolts to the deck. I believe the main purpose of these ring bolts was to attach ropes with hooks that could then secure the wheels during transport / anytime one would not want them free to turn. 

 

Now my attention will turn to finishing the wheels. Simultaneously, I will start working on the scoop mechanisms. I guess it is also time to select a mounting / display mode for the vessel. 

[druxey]

This is looking better and better, Greg!

[Greg Davis]

Today I finished the small wheel; i.e., got all of the fasteners in, attached the wheel to its axle, and oiled the assembly.

I have also completed the planking on the big wheel. It is now ready for fasteners and finishing.