Rattlesnake 1782 by Gregory - Scale 1:48 - Plans from ModelShipways & NMM

[Gregory]

Sam,

I apologize in advance if I am assuming what you may know or not know about laser work , so I will go over a few of  the basics.

Also, I am 'flipping' the piece in the drawings to be used by the laser.  After cutting the piece will be  flipped before gluing together.

 

This image is somewhat exaggerated but it shows that the laser beam is cone shaped above and below the point of focus.( this is a C02 laser that uses infrared energy )

 

 

When I refer to flipping, I'm flipping the part in the drawing that the laser uses.  It is like a mirror image.

 

 

 

The gap without flipping is not as great as shown above, but  enough to be noticeable as I will show later.

 

 

I like this example from Chuck's Winchelsea.  The parts with an X were flipped in the drawings for the laser.

Chuck uses a much higher-end laser than I do, and he is able to minimize the cone shape kerf with finer power and focus adjustments than I have.

 

Please let me know if I can explain or illustrate it further.

 

 

 

Edited September 16, 2022 by Gregory

[src]

Gregory,

I understand now.

I completely understand what you are saying about the laser, somewhere I missed the fact that you are cutting your own pieces; the perils of coming in late. We work with both water jet and laser cut parts where I work. Laser cut parts are usually very thin sheet metal and waterjet parts are thicker structural parts to be welded, so usually the kerf is not an issue for us.

Thanks for the explanation.

Sam

[Gregory]

A tale of two pixels, or minutiae madness.

I have been trying to refine my drafting process for using a laser for cutting parts.  My goal is to get nice tight joints where the various pieces go together.

I'm sure the pro's have different/better ways of doing this, but this is how my work flow has evolved with the tools I have .

 

These are the stem parts I developed, loosely following the MS plans which loosely follow the NMM plans.

Separating the parts out by color is fairly simple, and I'm using a .bmp format which should provide a pixel to pixel match.

But no matter how much I tweaked my drawings, down at the pixel level, I was not getting the tight joints I wanted.  ( See Ver 1.0 )

( This was after accounting for the difference in kerf angle as discussed above. )

 

I finally discovered that the squareness of the scarf corners was making the difference in how my cutting software was tracing my images, to make the vector drawings to drive the laser.

The difference in these two drawings is very subtle, and you might wonder why it would make a difference.  I sure did wonder why..

 

 

 

The blue image on the left above was being traced like this ( red line), which produced the slightly rounded corners seen here.

 

 

After I tweaked a few pixels I got the square corners seen here.

 

To recap: Ver 2.0 is the result after refining the corners.

 

Hats off to the guys out there using chisels and coping saws who get these results and better, without a laser in sight.

 

Edited September 17, 2022 by Gregory

[Dave_E]

You guys and your software and expensive tools amaze me. You take modeling to a crazy higher level. My hat is off to you for your knowledge and engineering capabilities! In a prior life you might have been a shipbuilder? 😀

[src]

Gregory,

Your version two is much better.

A question; what software are you using? It looks like a photo editing software if it is pixel based.

You want a vector based drawing package such as Illustrator or Rhino to truly get smooth curves (Read $$$). We use both for our cnc files where I work. There may be others out there that are more budget friendly or even free, I am not aware of them. Many people use Sketchup, but you still will not get true curves, you will get facets and your laser will have to start and stop at each of those facets even if you have so many facets they are very hard to see. That just gave me a thought, if you were to use sketchup you should be able to nest the facets together and get a better match?

Thinking out loud here.

Sam

[Gregory]

I really appreciate your input.

 

$$$ And a new learning curve is what I'm trying to avoid for software at this point.  I have a comfort zone with Adobe PS Elements that I established long before I had a need for vectorized files.

I use Adobe to create the shapes, then LightBurn, for my cutting software, does a really good job of tracing and vectorizing.

 

This was just a learning experience re. the sharp corners embedded in a curved shape.

An extra pixel thrown in, or in my case, not accounted for if I diverged slightly from a 90 degree corner, caused LightBurn to trace a slight curve in the corner apex which was enough to hinder the tight fit.

 

 

Edited September 18, 2022 by Gregory

[Gregory]

Complete Ver 2.0 in AYC.  Should have the cherry version to compare soon.

[VTHokiEE]

That looks very nice; I’ve enjoyed working with AYC so far but I haven’t worked with that many woods and am curious how it’s looks next to cherry.

[Gregory]

Should have the new cherry version soon.  Waiting on some new stock.

[glbarlow]

That looks nice and tight. Well done. Very cool how you’re cutting your own. As a photographer I use Photoshop but never touched anything to do with vectoring, looks like you’re on your way to mastering it. 

[src]

That looks really, really good. cant wait to see what it looks like in Cherry. The contrast of the char and the wood is very nice, it will be interesting to see the contrast on the Cherry. Since glue will not stick to char what is your plan for gluing them?

 

 

[Gregory]

5 hours ago, src said:

Since glue will not stick to char what is your plan for gluing them?

 

It depends on the amount of char and the type of wood..  I brush off any loose char, but my experience has been that it doesn't behave differently than fine sawdust, which could cause a bonding problem if it forms a relatively thick layer that keeps the glue from penetrating the wood.

I use yellow PVA, and as long as it is penetrating the wood, it forms as good a bond as when the pieces have no char.

 

The char creates the "caulking look".    I use this for my deck planks also.

 

 

From my Resolution build.

[Gregory]

Shipbuilding is suffering due to a deck rebuilding project.

 

 

Replacing 1 x 6 with 2 x 10..  Shouldn't have to do this again for another 30 years or so..

The old 1 x 6's were nailed, so the demolition is 90% of the work.

[Gregory]

I actually finished a few weeks ago.  That's not varnish. It was raining.  I probably won't seal/paint till at least spring, to make sure the pressure treated wood has dried out.

 

I'm surprised how much difference my earlier sizing errors made.  This looks even bigger due to perspective, but it will be a big model.

I'll explain the weird looking bulkheads.

The new backbone. The stem is glued in place, but not the keel and sternpost.

 

I'm pleased with the joinery a achieved on the stem.

This shows the biggest fairing issue I found at bulkhead I ( i ) ..

Rather than just shim it up, I cut some profile pieces based on the bulkhead  and glued them to each side of the bulkhead.

 

With the plank glued to adjacent bulkheads, I glued the shims in place.

I did some similar work at Bulkhead E, but the alignment was much less pronounced.

I'll be filling and/or sanding less severe problems as i proceed with the first layer of planking.

 

 

I documented earlier how I built up the counter filler to get a good initial shape that required less brute sanding.

 

 

I decided to try something similar with the tapering of the " stern filler " area ..  I'll update when I have these pieces in place.

Trying a similar approach with the bow.

 

More to come.

[Oldsalt1950]

Love how you dealt with the bulkhead issue and the filer blocks. Looks much easier.

 

Jim

 

[yvesvidal]

22 hours ago, Gregory said:

 

Very nice planking 🙂

 

Yves

[Gregory]

Work continues slowly on the main body, but I decided to work on a side project or two.

I've had this in my stash for a while and I was thinking it might make a nice addition to the Rattlesnake.

 

Lengthwise it scales almost perfectly.  Since the longboat is an embellishment not included on the NMM drawings  ( not typical ),  I think any representative boat should be acceptable.

The MS plan for the boat is somewhat lacking in my opinion.  I think the kit builders might do well to consider one of the boat kits from Vanguard.

I don't plan on going into a lot detail on the construction of the boat.  There are several excellent logs here and Chuck's instructions, available at, well, you know where, are an excellent practicum.

About the only parts I will be using from the kit is the false keel ( backbone ) and the bulkheads.  I am using boxwood for the stem, keel and related parts.

I decided to add a scarf to the stem, and made the rudder out of two parts.  It seems to me that those parts would not have been made from a single piece of wood.

If anyone has any ideas or information about making the joinery more realistic, I would welcome the information.

I will plank with boxwood.  The details will be boxwood and cherry for some contrast.  I don't plan on painting, so I hope to use different woods to good effect.

Just to share some construction mishap.  I broke off the little tab on the false keel twice.  The lengthwise grain at a very narrow junction might as well be a perforation. 

I then made a new piece with the grain rotated 90, so hopefully that is not to worry about now.

I tried to make the 1/32 rabbet, but ended up trimming it off and added a 1/32 strip down the center of the backbone for the rabbet.

I plan on making some other side projects with the capstan, the cannon and others to be decided.

Thanks for looking in.

 

[Gregory]

Whipped up the rudder and tiller.  Didn't want to fuss with them too much, as they will be stored in the boat somewhere and not mounted.

Cut the tiller out of 1/16 box..  Surprisingly, managed to end up with what you see  without breaking anything.

Really appreciating the properties of boxwood in this regard.

If anyone would like to have the extra left over, let me know.

 

[Gregory]

A little side trip regarding the guns.

Some of the builders of the MS kit have noted  a lack of satisfaction with the MS plans and parts regarding the guns.  I believe this criticism is Justified.

 

There appears to be no contemporary documentation of the size of the guns.  All plans are derived from the lines found at the NMM, which give no indication of gun size or number..

There are 10 ports per side, but I agree with Hahn that the two forward ports offer little room to work the guns.

Campbell's plans, which the MS plans are based on, call for 6 pounders, and Hahn calls for 6 pounders also.   I certainly have no expertise that would suggest another number would be a better fit.

However, Campbell and Hahn seem to have  come up short ( pun acknowledged ) when it comes to the dimensions of these guns.

All of my research indicates a 6 pounder would be at least 6 feet long.

Goodwin in the AOTS Blandford, has the 6 pounder at 7'6" ..

 

 Here is what my rough scaling comes up with.  I agree with Dave and John that the Syren 29.75mm barrel is a good fit.

 

I have had problems with scaling before, so if anyone comes up with different numbers, please feel free to correct me.

 

I think the Syren 39.69mm, that scales to about 6'3" at 1:48, is a good fit for my model.

 

Here is a first fit on my build with the Syren barrel.  

I hope to be able post a more detailed log update soon with my approach to gun/oar port framing.  My long boat build has stalled, but it will continue.

I have found myself distracted lately with some related projects, including the capstan and gun carriages .  Spending a lot of time adapting the drawings to use with

my laser.

 

[Gregory]

My progress has really been hit and miss the last three months, and I seem to have trouble reaching a point where I think a log update is worthwhile.

Anyway, here goes.

 

 To simplify the gun port and oar port framing, I cut out these frames to establish location.  Doing it with the laser really simplifies uniformity.

I put a plank in place to establish the sheer, and am using this for the initial placing of the gun and oar ports.   All the ports had not been established in this image.  I am not following the plans precisely, however I am going for a balanced look with the spacing.

My plan is to get some solidity to the upper body before before continuing the lower planking, because I keep breaking the bulkhead extensions, particularly on the quarterdeck, which leads me to some of the details I have been working on there.

 

 

 

I built the capstan from the Syren kit for Winchelsea a couple of years ago.  At the time, it was to be used for my Resolution build, which has stalled due to some rigging issues.  I had the 1:48 Rattlesnake build in mind at the time, so the Syren kit was still an option I was considering. 

 

The Syren cherry kit ( upper part ) in place on my Resolution.

 

I opted to use the drawings from Winchelsea and make a capstan from pear, this being the result.   Probably not the final version, as looking at my pictures makes me want to try to improve the detail.

 

 

The grating was made from a Syren cherry kit.

Once again I used the Winchelsea drawings.  This time to make a ladder.

 

 

One of those little touches that won't have much visibility when all is said and done.

That's all for now.  Thanks for looking in.

 

Edited June 26, 2023 by Gregory

[glbarlow]

Nice work making your own from drawings. Well done!

[Gregory]

Long time no update but I haven't been idle..  Sidetracked on a couple of other projects, and being less satisfied with how the hull is shaping up.  I will have more on that later.

 

They say " The Devil is in The Details ", and boy, is it.  In any event it all has to be done sooner or later.

 

I discussed the design of the quarterdeck bulkhead a while back.  As discussed, the drawing in the MS plans by Campbell is his ( expert? ) interpretation, and essentially duplicated by Hahn and Mamoli.  No expert here, but I find the windows in the center panels and not the doors a bit incongruous.  I made a back piece with etching on it and a frame to fit over the back, in which I was thinking about inserting panels and doors.

Going forward with a prototype, I decided to try some laser assisted carpentry.  I don't want to paint, but going with bare wood calls for careful planning to avoid wood grain going in one direction in a continuous pattern, and I also want to avoid a strong variation in wood color across the whole assembly.  I am also learning some important considerations when doing this with a laser.  The arrow points to where the middle column should fit, and there is about a 1mm gap.  What I didn't account for is what I now call " Kerf Creeping ".  The kerf of my laser is less than .5mm and there is a kerf offset built into the software to account for the kerf, but it takes some tweaking, as well as optimizing the focus and keeping the lens clean.  Considering I had 12 vertical joints going from left to right, and a gap of ~1mm, that means my kerf was too big by about .08 mm.  So, I am going to have to adjust for that next go around.  It might just be a matter of cleaning the Laser lens.

I didn't spend a lot of time cleaning off the laser char, and I think doing more of that will make for a better look.  I think the upper and lower framing might look better if there is one continuous piece/ beam. 

I'm also looking forward to see how Chuck approaches the bulkhead with his Speedwell build.  I'm sure I will get some ideas for refining my methods.

 

 

[glbarlow]

Ambitious and well done. Working with a laser is beyond me, impressive work you’ve done with this project. 

[Gregory]

Thanks Glenn.  Always glad to know you are watching.  I continue to be inspired by your craftsmanship.

 

Thanks to everyone for the 'Likes' . I appreciate everyone who is looking over my shoulder.

Edited February 24 by Gregory

[scrubbyj427]

Some very nice laser work on that bulkhead.

[Gregory]

Thanks scrubbyj.  Really means a lot coming from you, considering the work you do with the laser.

[Gregory]

 

Version 2.0..  Made this with pear.  While I really like the cherry, the grain is really too much for these small pieces.  I got rid of the " kerf creep ", but there is still fine tuning to do.  ( Which one of those panels got sanded too much? 😁 )

I have another idea or two I want to try, so " I'll be back " ..

 

[CiscoH]

I agree the grain is better (much less obvious) with the pear.  Beautiful panels and the hardware looks to be in perfect scale.  If I may add a subtle critique, and I understand this is a test piece and maybe you already know this, usually the bottom stile of the door is wider than the middle and top ones (see the dashed line in the plans on your post #82 which shows this).  The same goes for the bottom stile of the curved side panels, which in the plans are level with the door bottom stiles so its a nice horizontal gentle curve following the deck camber. 

But I nitpick.  No offense to anyone who feels otherwise but to me laser-etched panels and doors stand out because they dont look real; I feel your test piece is way above the pre-fab kit parts.

[Gregory]

Your quibble is the type of input I'm looking for.  Thanks.

Yes, I had simplified things by making that sort of baseboard at the bottom of everything.

 

 

Should the plain of those features follow that curve all the way up?  Now that you mention it, the Campbell drawings seem to reflect that to some extent

Are you aware of any contemporary drawings that show this?

 

The panel beveling is a real challenge at these scales.  Trying to get that right is really delaying this project

 

All quibbles and nitpicks are welcome.

 

 

[iMustBeCrazy]

2 hours ago, Gregory said:

Should the plain of those features follow that curve all the way up?  Now that you mention it, the Campbell drawings seem to reflect that to some extent

I suspect that the verticals were indeed vertical and that the horizontals followed the curve of the deck (but were actually straight lines themselves) except perhaps at the head. This would make the panels parallelograms (except the outside ones and perhaps the middle ones).

The five columns (blue) were probably proud of the 'wall'.

But there's also a good chance I'm wrong.

 

2 hours ago, Gregory said:

The panel beveling is a real challenge at these scales.

The standard answer is 'make a jig', it may take twice as long but it will give better results.