1949 Chris-Craft 19' Racing Runabout by gjdale - FINISHED -Dumas - 1:8 Scale - RADIO

[mtdoramike]

All I can say is WOW, What a real beauty.

 

 

mike

[John Allen]

Grant

 

You never cease to amaze, I've been following your builds since your Victory (thanks again for your help on mine) whats next scratch build of an R/C Queen Mary. 

 

You put a lot of TLC in the Chris Craft it shows

[gjdale]

Thanks guys.

 

Keith - yes, I was aware of the little bit of "orange peel" but am confident I will deal with that with the remaining coats and sanding. Thanks for the links for the micromesh - I've got some really small pieces (about 50mm square) but was starting to think about finding some on a larger scale. I've just ordered a bunch from the linked site, so when the Admiral asks, I'm blaming you okay?

[gjdale]

A Stand and some Graphics

 

Now that the finish on the hull is approaching a state that I’d like to preserve, I decided that it was time to make a stand. So today that’s what I did. Not sure yet if this will feature as part of the final display but in the meantime, it is quite functional. It is simply made, copying the design in Pat Matthews’ excellent book. The uprights are 16mm dowel, while the cross-braces are 8mm dowel. I finished it off with Vallejo Metal Colour “Chrome” and the Vallejo Metal Varnish (Gloss), all applied via the airbrush. One advantage to using these paints is that they dry almost instantly. A coat of primer, a coat of colour, and a coat of gloss, all applied in quick succession through the afternoon. The contact points have a self-adhesive felt applied for protection.

 

 

Then it was time to apply the graphics. I first gave the entire hull a light wet sand wit 600 grit paper, so the overall look is a bit ho-hum (the gloss will return with the next coat of clear). The graphics are vinyl and come from Callie Graphics in the US. I went there following a recommend of several others over on the RC Groups forum and must say that I’m delighted with both the service and the product. I had a quick email conversation with Callie, sent her a pdf of the general design and told her what they were for.  She quickly came back with some proofs for me; we made one minor change; another set of proofs and we were in business. A few days later the finished product showed up in the mail. I ordered two complete sets and with postage the whole lot cost me less than AUD $20.

 

So now for the big reveal!

 

 

I may have mentioned that this is going to be my wife’s boat, so it is named for her, Georgina. Georgie Gerl (yes, the spelling is correct) is her email “handle”.

 

And of course, one must have the Chris Craft logo and a registration number:

 

 

If you look closely, you will see that the registration number is GE 041282 GD, which is a combination of our initials and the date of our wedding (in non-American date format). I know, I’m just an old romantic…….. The admiral inspected the graphics on completion and has given her seal of approval. 

 

Next up, sealing the graphics under several more coats of clear varnish……………

[Keith_W]

Awww, how sweet  

[Rustyj]

Hi Grant.

 

Just got back and enjoyed getting caught up on your build. She looks fantastic! Well done.

[popeye the sailor]

love the graphics........it's very common to fool with the spelling.....fishing boats are a good example.   great job Grant!

[mobbsie]

Hi Grant

 

Graphics look great mate and are a very nice touch, bit of a romantic really aren't you.

 

The stand looks functional and will not detract from the boat if used in your final display, simple yet very effective.

 

I'll also wish you a Very Happy Birthday my friend, still a young pup at 56.

 

Be Good

 

mobbsie

[mtdoramike]

When I saw the name, it instantly made me thing of that commercial with a big burly biker guy getting a tattoo from a girl, who was eating a Snickers bar. When she finished the tattoo and the guy looked at it, it said "No Regerts". Her excuse for the foul up was that she was eating a Snickers bar. hahahaha. I'm glad to see that the spelling was intentional though on your model. The naming should score you some huge brownie points with the lady of the house.

 

I have no Regerts!

 

 

mike

Edited November 28, 2016 by mtdoramike

[gjdale]

Thanks again for all the kind comments and all of the "likes".  

 

Another mini-update.......

 

After a further three coats of clear finish, with wet-sanding between coats using 1200 grit paper, I think we are done with the spray-gun at last. I’m quite pleased with the way that it has come up, although the camera can be a little unkind. It looks better to the naked eye! It still needs several hours’ worth of polishing before it’s really done, but here are a few glam shots by way of update.

 

 

 

 

 

 

 

 

[Gerhardvienna]

Another mini-update.......

 

 

 

 

Hi Grant

 

MINI-UPDATE????????????

 

So well done, I cant wait to see her with all the lids, hoods and miscellanous parts. I like it!

 

Regards

Gerhard

[cog]

Grant you seem to underestimate yourself. What to you is a mini-update, is a big one for others - me included. She looks more lovely every time ...

[Keith_W]

Don't stop now, Grant. There are still a few little ripples in the finish! I am excited with your build, I think what we are going to see is the first perfect gloss finish on MSW. At least, it WILL be perfect if you keep at it! So here's a shout of encouragement. 

[captainbob]

She's a beauty.

 

Bob

[rafine]

Simply beautiful Grant.

 

Bob

[donrobinson]

WOW

[Rustyj]

Well done Grant!

[Trussben]

Very very nice Grant.

 

Ben

[src]

Grant, that looks awesome and deserves every bit of praise you have received and more. Put her on a shelf and she will be an eye catcher for sure.  

I agree with what Keith said though, a little more leveling and she will be a show stopper!

Just my two cents, carry on!

Sam

[gjdale]

Many thanks as always for all the kind comments and the "likes". On with the show....

  Of Moulds and Wheels

 

Before completing the finish on the hull, I decided to take a little diversion in two directions. Firstly, I decided that it would be a good time to make a mould of the bow so that I could work on the cutwater off the model (and hence protect that lovely surface). And secondly, I decided it was about time to start tackling the building of a new steering wheel.

 

To make a mould of the bow, I bought some plaster from the local art store. I could have gone all fancy and bought some very expensive mould making material, but as this is a one-off job, I decided to keep it simple and inexpensive. To create the mould, I mixed up some plaster and water and then suspended the boat above it by looping some brass wire through the rudder post, then attaching some rope hooked over the garage door tracks, and then lower the boat into the plaster. Of course, I had taken the precaution of wrapping the bow in cling wrap first!

 

 

Once the plaster had set, I removed the boat and coated the mould with some silicon grease to act as a release agent. Then I mixed up some more plaster and water and poured it into the mould. I also inserted two pieces of dowel to use as “handles” later on. In this picture, the cast has set and I have cut around the top edge prior to lifting out.

 

 

And here is the final product:

 

 

After this photo was taken, I cleaned up the cast with a light sanding and then painted it with a coat of finishing resin to (hopefully) prevent it from crumbling as I work with it. More on the cutwater to come at a later date.

 

I had decided to replace the kit-supplied steering wheel after reading an excellent “how-to” by Kip Catanese over on the RC Groups forum. Kip made a replacement wheel for a fellow forum member and documented his process so well, that I decided to try and replicate it – at least as far as I am able.  What follows then, is an implementation of Kip’s methodology. I hope I can do it justice.

 

The starting point is a piece of 1/8” diameter brass rod. This needs to be bent around a form and then silver soldered to form our basic wheel. To create a form, Kip turned a “buck” on his lathe to the correct diameter to match the finished wheel’s Inside Diameter of 2” (50mm). This is slightly smaller than the kit supplied wheel as Kip reckoned it was a little too large for the scale. That’s good enough for me Kip!

 

So, following Kip’s lead, I laminated two pieces or 2 ¼” square x ¾” scrap timber together with epoxy, marked the desired diameter, mounted it in a four jaw self-centering chuck, and then turned the outer portion down to the correct diameter. Although Kip used hand tools on his lathe for this operation, I stuck with regular metal cutting tools and they worked just fine. Once the outer portion was turned down, I drilled a 1/8” diameter hole in the cylindrical section to anchor one end of the brass rod, and then drilled and tapped an M6 thread into the square section of the buck. The purpose of this will become clear shortly.

 

 

In order to bend the brass rod around the buck, it first needs to be annealed to make it soft enough to bend easily. I had not done much in the way of annealing before, so had a go with my little butane torch that I use for silver soldering. Well, all I can say is that this was an abject failure. I stopped and thought about it for a while and concluded that I simply wasn’t getting enough heat to the rod overall. A quick (and not inexpensive) trip to the hardware store solved my problems……

 

 

This little torch uses something called Ultra Gas, which apparently is the “next generation MAPP replacement”. I wouldn’t know about that, but what I do know is that it heated my brass rod to cherry red in no time at all, and after a quick dunk in a bucket of water, it bent like a piece of soft rubber around my buck.

 

 

In the picture above, you can see the purpose of the threaded hole (again a direct copy of Kip’s method). I have used an M6 socket head screw with a “mudguard” washer to hold down the very end of the brass rod and keep it nice and tight on the buck while it is being cut. After this picture was taken, I moved the threaded hold-down to the next face around (ie 90 degrees) as I found this to be more secure.

 

The whole assembly was then mounted in the milling vice and the ring cut using a slitting saw. This ensured that the two mating faces were perpendicular to each other.

 

 

Once the piece was cut free, it was placed back on the buck with a hose clamp to ensure that it remained as true to shape as possible. 

 

 

Then it was just a simple case of silver soldering the ring closed and doing a little clean up with a file.  Here is a picture of the finished ring, alongside the original kit-supplied wheel. You can see that it is slightly smaller – the outer diameter of the new wheel is about the same size as the inner diameter of the kit wheel.

 

 

Next up, thinning and shaping the exterior of the wheel, and then milling the finger crenallations. So far Kip’s treatise has been a dream to work with. I’m hoping that the remainder goes as well!

 

[mobbsie]

Hi Grant,

 

I'm intrigued to see how you develop the cutwater, I've never seen this before mate, looks interesting.

 

Good luck on getting the wheel centred, that's not going to be easy but I think I know how your going to tackle it. Just don't make it too complicated though, you know I don't do complicated !!!!!!!!!!!!!!!!!!!!!!!!

 

Watching with great interest my friend.

 

Be Good

 

mobbsie

[popeye the sailor]

really super finish Grant..........interested with how your making your wheel........looks like a cool process so far.

[gjdale]

Thanks for dropping in Mobbsie and Popeye, and thanks to all who hit the "like" button.  On with the show....

 

Wheel Building

 

Once again, I’m following Kip’s process for this. The next stage was thinning and shaping the wheel and adding the crenallations (finger grips). It took me a while to get my head around the cross-section shape of the wheel, but essentially it is egg-shaped, with the thinner part of the egg towards the back of the wheel (actually the forward side), where the finger crenallations will be. A couple of emails back and forth with Kip, and finally I understood what I was doing.

 

To begin with, the soldered wheel was placed back on the wooden forming buck. Because of the removal of the saw kerf from the diameter of the wheel, it was now a very tight fit on the buck, and so it could be spun on the lathe while files were applied to create the shape. First of all, the thickness of the outer rim was reduced by 1/32” by using a flat file.

 

 

Then the outer part of the back face was given a slight angle, again with a file. The wheel was then removed from the buck and held in the lathe chuck so that the inner part of the back face could also be angled, giving a very slight “v” shape to the back part of the wheel.

 

 

 

Now we needed to create a jig to hold the wheel while the crenallations were milled. Once again, I followed Kip’s lead and turned a piece of 75mm diameter HDPE (a plastic of sorts) with a 2.37mm deep rabbet around the outside, such that the wheel would just go over it. I also centre-drilled the jig while it was there.

 

 

I had never used this material before, but after reading Kip’s method, I stumbled across a piece of exactly the right size in my local machinery supplies shop and they let me have it for free – just goes to show how much money I’ve spent there…….

 

Anyway, this material (which I believe also goes by the name of Delrin), is a joy to work with. It machines beautifully and can be tapped and threaded with ease. So, the next job was to drill and tap some 6-32 mounting holes for some hold-downs.

 

 

 

Hold-downs were made from 1/16” brass strip, 1 inch long by 3/16” wide, drilled for clearance for the 6-32 socket head screws. A strip of honeycombed rubber (off-cut from a non-slip drawer liner) was inserted under each strip. The wheel was then mounted on the jig, the jig on the lathe chuck, the lathe chuck on the rotary table for the mill, and the rotary table on the 90-degree angle table. As Kip says, that’s a lot of mounting!

 

 

Okay, time for some milling……almost…….

 

Kip noted that the original wheel had either 12 or 13 crenallations in each of three 120 sections. The sections are separated by the spoke holders, where there are no crenallations. He estimated that the spoke holders cover about 10 degrees each, leaving 110 degrees of arc to fit the crenallations into. Kip did the math on this and worked out that for 12 crenallations, the centres needed to be 9.17 degrees apart. Way too hard for me Kip – too much chance of going wrong. I decided I would use 11 crenallations, making them 10 degrees between centres, which just happens to be two complete turns of the hand wheel on the rotary table. Much less chance of stuffing it up, and who’s going to notice anyway? Kip also advised using a 3/16” end mill and cutting to a depth of 0.0255”. Seriously Kip? And you think we’re crazy with our metric system! So, that converts to 0.65mm (rounded to two decimal places). I was still a little nervous about how this was going turn out – I didn’t want to be making several “practice” wheels, so before going near the mill, I sat at the computer for a couple of hours and played with my CAD program to work out how these would take shape on the wheel. It was an interesting exercise – that merely proved that I should have just trusted Kip in the first place and saved myself two hours! So, off to the mill.

 

 

In the above picture, I’m about one third of the way through milling the crenallations. It all went smoothly, except that the hold downs were a very tight fit between mill passes. In fact, the mill shaved a little off them as we went.  The only issue I had was that the silver solder joint failed during the process. Fortunately, that didn’t affect the rest of the milling. Here is the completed part fresh off the mill and before clean-up.

 

I used a scrap piece of MDF and quickly drilled and tapped some 6-32 holes so that I could use my hold-downs again while I re-soldered the join.

 

 

Once the soldering was completed, it was simply a case of cleaning it all up with some files and sandpaper. And here is the finished wheel rim:

 

 

I’m pretty happy with the way it turned out. Thanks to Kip’s trail blazing, I managed to get this on the first go. The next task will be making the spoke attachments for the rim. Stay tuned…..

[Keith_W]

I love this. I will most definitely stay tuned. 

[mobbsie]

WOW, your definately moving up to the next level of skills here mate, that is some really good engineering.

 

Is there any difference in the weight of the original wheel and the new one. ? just thinking about ballasting and overall weight of the boat.

 

Makes me wonder if your ever going to find satisfaction in the general kits available, the skies the limit mate.

 

I am watching.

 

Be Good

 

mobbsie

[Canute]

Nicely done on your steering wheel, Grant.

 

Never knew you could machine Delrin so nicely. Thought parts were injection molded.

[src]

Nicely done! I would never have considered Delrin for a hold down. I will have to remember that one. Makes great bearings btw.

Sam

[popeye the sailor]

you've really raised the bar on the home made steering wheel      fluting looks cool!

[gjdale]

Thanks Keith, Mobbsie, Ken, Sam and Popeye for your generous comments, and to all those who hit the "like" button.

 

Wheel Building Continued

 

The spoke holders, which will be attached to the inner face of the wheel rim, were next to be machined. These are milled from a piece of brass stock 1/4” wide by 1/16” thick. The outer end of each piece needs to be milled with a convex radius of 1” (to mate with the 2” diameter of the wheel). Additionally, the end needs to be cut with a concave surface so that it will mate cleanly with the curved surface of the wheel rim.

 

Kip gave a good description of his process, using the rotary table to achieve the convex radius and a 3mm ball-end cutter to achieve the concave cut. While it took me a while to get my head around all of this, eventually it made sense. However, I came unstuck in trying to follow Kip’s method exactly as he used a narrow vice to hold the parts while milling the 1” radius.

 

Without a thinner vice, I had to devise a holding jig of some sort. It took several days of thinking through but I got there in the end…… I started by drilling a series of 9/16" clearance holes in the 1/4" x 1/16" brass strip, starting 10mm from the end and then at 15mm spacing between centres. I then drilled and tapped two 6-32 holes in a piece of scrap timber such that one was centred 5mm from the end and the other 20mm from the end. This meant that when I attached the brass strip to the timber, it would be held securely with 5mm overhanging the end of the timber while the rear most cap screw would be centred 25mm from the end of the brass. Then I just needed to align that cap screw in the centre of the vice, over the centre of the rotary table and then offset that centre from the cutting bit by 25mm (+ 1.5mm for the radius of cutter). Here is a picture of the overall setup.

 

 

And a close-up of the holding jig:

 

 

After making the first pass to create the end shape, I removed the strip from the jig and cut off the end at a pre-marked point using a razor saw and mitre box. Because of the threaded hold-downs, I was able to remove and replace the strip in the holding jig without changing any settings on the X,Y or Z axes of the mill by simply undoing the 6-32 cap screws. After cutting off the freshly milled piece, I simply re-installed it with the next set of holes to have the end protruding exactly the right amount again and we were ready to repeat the milling cut.

 

Here is another close-up of the milling in process:

 

 

And here are the five resulting pieces ready to be cut to final length. I only need three of these but thought it best to make a couple of spares. Turned out to be a good decision!

 

  

The next step was to cut these to final length. According to Kip’s instructions, that length was to be 7/64”. I converted that to metric to make it easier to operate the mill wheels, and rounded up slightly to 3.0 mm. In order to cut these precisely to the same length, I made a jig to hold them in the mill vice while I used the slitting saw to make the cut. The parts were held onto the jig temporarily with CA glue. Here is the setup:

 

 

It turns out that CA is not a good choice to use for this purpose. When it heats up the bond gives way fairly easily. I’ll put that one in my Homer Simpson “Doh!” file!!! So, those extra two parts came in quite handy as by the time I’d completed the cut, two of the “keeper” ends had vanished (although I had all five of the “offcut” ends!).

 

Here’s a pic of the final parts cut to size. The tweezers in the background are to give a sense of scale.

 

 

And just in case that doesn’t do it for you, here is a shot with all three of the pieces on the fingernail of my index finger.

 

 

Man, these things are small!  And the next job will be to drill a series of 0.5 mm holes into the long narrow inboard edge to receive the spokes.  Stay tuned….

[Captain Slog]

Great stuff Grant, you are certainly well set up for creating these parts.  Look forward to seeing the finished article.

 

Cheers

Slog