Dumas 1/2A Atlas van lines build
10-11-2009, 10:30 PM
#26
RE: Dumas 1/2A Atlas van lines build
The saddle tank is kinda standard affair with hydros but usually the tanks are each side of the engine bay. What type of pressure will you be running? Off of the backplate or the drilled nipple on the intake?
I think the .15 would be perfect for that boat, and the .09 wouldn't do too bad either. The problem with running the .15 as a marine engine is cooling. The Dumas cooling jacket can be machined out to fit over the .09 fins without hitting the tubing inside, but it wont go as large as the .15 unfortunatly. The same goes for the buggy radiator.
Good that you pointed out the #4 bulkhead being removed. It's good to know ahead of time if it needs to be cleared out so nothing gets glued where it shouldn't. I've made that mistake before and it's really hard to chop out when that happens.
I think the .15 would be perfect for that boat, and the .09 wouldn't do too bad either. The problem with running the .15 as a marine engine is cooling. The Dumas cooling jacket can be machined out to fit over the .09 fins without hitting the tubing inside, but it wont go as large as the .15 unfortunatly. The same goes for the buggy radiator.
Good that you pointed out the #4 bulkhead being removed. It's good to know ahead of time if it needs to be cleared out so nothing gets glued where it shouldn't. I've made that mistake before and it's really hard to chop out when that happens.
10-11-2009, 11:06 PM
#27
RE: Dumas 1/2A Atlas van lines build
RJ, am I seeing this right, the skid fin doubler is on the inside of the sponson transom? About time Dumas did something right. You need to make the lightening holes in the sponsons bigger, at least double the size you show in the pictures. I know the wood quality is poor but you can still take more wood out of those frames. Let me show you what I mean. Granted, mine is a bigger boat, but you can still remove atlleast half of the material out of the middle of each frame
10-12-2009, 01:23 AM
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RE: Dumas 1/2A Atlas van lines build
Actually addingthe skid fin doublerwas my idea as its not mentioned at all in the instructions. This hull was originally intended for tether line.
But I'm going to set it up for right turn ovalracing....I wonder if this hull can handle an .09? The boxdoes say "A" or "1/2A"..Whats an "A" engine size? If a .049 is 1/2A then Iassum an "A" is what. a .10? If thats the case thena .10 may be able to swing a X430-X632 I'm hoping.....I do have a couple dumas props for a .10.
The wood is thin and fragile so I chose to do the cutouts after some assembly was done. But I still need to cutout the stringers up front and the sponson stringer outside the engine well. I can probably work a bit more on the sponsons and make the cut outs bigger, but it is a very tedious job cause of the small size and thin wood. How I did it was by using a tiny pin vise and made tiny hole in the center of each piece, then I grabbed my dremel and on its slowest setting very carefully drilled the holes out larger, then shaped them with a cone wood stone.
Again on a slow speed cause any higher you risk having it catch the wood and run away from you....and it wouldnt be pretty...
The center of #4 inside the engine well is the only piece I would remove. again I'm going to add 1/8 balsa along the tops of the stringers and perhaps in certain areas on the hull bottom and sponson insides to give more surface area for the deck and hull bottom....Theres really not much other than the tops of the stringers and bulkheads for the deck to hang on too...
I have the original instructions for the cox medallion engine highly stresses getting presure from the crankcase. Apparently there is a starter hole already made by cox so you can use the presure fitting on the side..all you have to do is remove the backplate, remove piston/cylinder and venturi/needle assembly. rotate crankshaft until port opening in shaft points towards the presure fitting and drill out the starter hole....with presure the venturi may be opened to 7/32" dia for max power.....
But I'm going to set it up for right turn ovalracing....I wonder if this hull can handle an .09? The boxdoes say "A" or "1/2A"..Whats an "A" engine size? If a .049 is 1/2A then Iassum an "A" is what. a .10? If thats the case thena .10 may be able to swing a X430-X632 I'm hoping.....I do have a couple dumas props for a .10.
The wood is thin and fragile so I chose to do the cutouts after some assembly was done. But I still need to cutout the stringers up front and the sponson stringer outside the engine well. I can probably work a bit more on the sponsons and make the cut outs bigger, but it is a very tedious job cause of the small size and thin wood. How I did it was by using a tiny pin vise and made tiny hole in the center of each piece, then I grabbed my dremel and on its slowest setting very carefully drilled the holes out larger, then shaped them with a cone wood stone.
Again on a slow speed cause any higher you risk having it catch the wood and run away from you....and it wouldnt be pretty...
The center of #4 inside the engine well is the only piece I would remove. again I'm going to add 1/8 balsa along the tops of the stringers and perhaps in certain areas on the hull bottom and sponson insides to give more surface area for the deck and hull bottom....Theres really not much other than the tops of the stringers and bulkheads for the deck to hang on too...
I have the original instructions for the cox medallion engine highly stresses getting presure from the crankcase. Apparently there is a starter hole already made by cox so you can use the presure fitting on the side..all you have to do is remove the backplate, remove piston/cylinder and venturi/needle assembly. rotate crankshaft until port opening in shaft points towards the presure fitting and drill out the starter hole....with presure the venturi may be opened to 7/32" dia for max power.....
10-12-2009, 05:34 AM
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RE: Dumas 1/2A Atlas van lines build
R.J,
The Cox TD .09 is an often under estimated powerplate. While being only an .09 is belts out power on the level of most .15's and yet is much smaller and lighter. Also while the instructions may say otherwise DO NOT use the timed pressure nipple off the side of the engine. Find a backplate with pressure tap and use it if you are wanting to run pressure.
Tim
The Cox TD .09 is an often under estimated powerplate. While being only an .09 is belts out power on the level of most .15's and yet is much smaller and lighter. Also while the instructions may say otherwise DO NOT use the timed pressure nipple off the side of the engine. Find a backplate with pressure tap and use it if you are wanting to run pressure.
Tim
10-12-2009, 01:54 PM
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RE: Dumas 1/2A Atlas van lines build
Can you please explain the differences and advantages/disadvantages between the difference ofthe nipple off the crankcase and obtaining presure from the backplate?
also, if I used the saddle tank arraignment how would the hoses be hooked up? Also, if the tanks are located in the sponsons as jetpack suggested, that would bring them alittle bit lower than the engine. Would that effect reliability/performance. I thought the tanks should be even or a touch higher than the engine....
also, if I used the saddle tank arraignment how would the hoses be hooked up? Also, if the tanks are located in the sponsons as jetpack suggested, that would bring them alittle bit lower than the engine. Would that effect reliability/performance. I thought the tanks should be even or a touch higher than the engine....
10-12-2009, 04:29 PM
#31
RE: Dumas 1/2A Atlas van lines build
RJ, the crankcase pressure is going to be much higher than the intake pressure. The backplate recieves all the volume that the piston compresses on its way down before the ports open up inside the cylinder. It's the soft pop you hear when the piston starts to get half way down after the compression stroke. That is all of your crankcase volume being compressed and let go into the port when the top of piston clears it. Try it with a drop of heavy oil each side of the piston once. The heavy oil helps seal the bottom of the piston when you do this, normally a looser fit than the top.
The intake pressure nipple takes the left over pressure from the intake charge, and it is a very short duration, very weak. Many people haven't had much success with the intake nipple approach, nor being able to hold any fuel hose to the nipple. LOL. It's tapered with no barb to hold the hose. The backplate method is also reversable if you have a spare backplate. If you drill the crankcase, you have to replace the plastic intake housing to re-seal, or change over to an un-drilled crankcase, or try and melt the hole closed from the inside of the intake body and trust it from there.
Plumbing the tanks goes like this. Your first tank only needs two holes, a vent and an outfeed. If there is a third, it needs to be blocked, soldered over or such.
The Pressure Line from your engine goes to the Vent 1 of Tank 1. Vent 2 of Tank 1 has to be plugged. You're left with the fuel pickup tube and one vent to connect.
Feed from Tank 1 gets pushed by air pressure over to Tank 2's vent. Tank 2 stays completely full the entire time Tank 1 gets pumped out before it starts to empty. This tank also has one vent blocked with it's feed line going to the carb.
To refuel you can use the pressure line going into tank 1, or disconnect carb line and fill from that end.
I'll try and draw a diagram. Hope someone else steps in and gives another explaination so its more clear.
Fuel pressure from the crankcase is more than enough to push the fuel through the system even if its all below the carb. To regulate it, you can use a rubber cap on tank 2's extra vent hole with a small drilled hole in it to expell the extra pressure. Trial and error on the size on that one, but I've seen it used.
Enginecrazy makes a good point about the .09 having some power for it's size and weight. You might want to look for a Queen Bee .074. They are laid out pretty well for boat use, about the same overall size of an .09 maybe a bit heavier. It's not a real powerhouse, closer to an .049 than it is to a TeeDee 09. It is a reed engine, not a rotory intake is like the TD's or Medallions, but it is a rear intake which accounts for some easy power but like all reeds limited on rpm's unlike the solid timed crank induction.
The intake pressure nipple takes the left over pressure from the intake charge, and it is a very short duration, very weak. Many people haven't had much success with the intake nipple approach, nor being able to hold any fuel hose to the nipple. LOL. It's tapered with no barb to hold the hose. The backplate method is also reversable if you have a spare backplate. If you drill the crankcase, you have to replace the plastic intake housing to re-seal, or change over to an un-drilled crankcase, or try and melt the hole closed from the inside of the intake body and trust it from there.
Plumbing the tanks goes like this. Your first tank only needs two holes, a vent and an outfeed. If there is a third, it needs to be blocked, soldered over or such.
The Pressure Line from your engine goes to the Vent 1 of Tank 1. Vent 2 of Tank 1 has to be plugged. You're left with the fuel pickup tube and one vent to connect.
Feed from Tank 1 gets pushed by air pressure over to Tank 2's vent. Tank 2 stays completely full the entire time Tank 1 gets pumped out before it starts to empty. This tank also has one vent blocked with it's feed line going to the carb.
To refuel you can use the pressure line going into tank 1, or disconnect carb line and fill from that end.
I'll try and draw a diagram. Hope someone else steps in and gives another explaination so its more clear.
Fuel pressure from the crankcase is more than enough to push the fuel through the system even if its all below the carb. To regulate it, you can use a rubber cap on tank 2's extra vent hole with a small drilled hole in it to expell the extra pressure. Trial and error on the size on that one, but I've seen it used.
Enginecrazy makes a good point about the .09 having some power for it's size and weight. You might want to look for a Queen Bee .074. They are laid out pretty well for boat use, about the same overall size of an .09 maybe a bit heavier. It's not a real powerhouse, closer to an .049 than it is to a TeeDee 09. It is a reed engine, not a rotory intake is like the TD's or Medallions, but it is a rear intake which accounts for some easy power but like all reeds limited on rpm's unlike the solid timed crank induction.
10-12-2009, 06:55 PM
#32
RE: Dumas 1/2A Atlas van lines build
I wouldn't use balsa, it's too fragile. I'd go with spruce instead as it can handle the vibration and pounding better without a major weight penalty
10-12-2009, 09:04 PM
#33
RE: Dumas 1/2A Atlas van lines build
HJ, I wouldn't hesitate on using balsa glue blocks for the deck, this thing is tiny. All the balsa is doing is holding the glue in place until it cures at the joint instead of just running down the side of the bulkhead. You can't expect to pool a bead of epoxy on 1/16th porous grain wood and have it stay on top to fill a gap.
If possible, flip the boat over after you deck it so whatever glue dripped down will drip back and hopefully cure in place. Epoxy will pool better around the bulkheads.
If you're using super glue its the same thing. It's just holding the glue in a trough along the edge of the bulkhead so it makes better contact. The balsa isn't expected to add any structural strength, they're just there to hold glue where you want it.
RJ, You were wondering about water lines, why dont you drill through the bulkheads within the cockpit area, and feed an aluminum tube through there? Were you thinking of bringing them up the sides?
Getting back to the saddle tanks you can see where the brass tube comes through the cockpit sides into the engine bay. The other side looks the same.
If possible, flip the boat over after you deck it so whatever glue dripped down will drip back and hopefully cure in place. Epoxy will pool better around the bulkheads.
If you're using super glue its the same thing. It's just holding the glue in a trough along the edge of the bulkhead so it makes better contact. The balsa isn't expected to add any structural strength, they're just there to hold glue where you want it.
RJ, You were wondering about water lines, why dont you drill through the bulkheads within the cockpit area, and feed an aluminum tube through there? Were you thinking of bringing them up the sides?
Getting back to the saddle tanks you can see where the brass tube comes through the cockpit sides into the engine bay. The other side looks the same.
10-13-2009, 07:09 PM
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RE: Dumas 1/2A Atlas van lines build
I grabbed some 1/8 squared basswood because myLHS didnt have any balsa, but yeah, I just want to give some areas of the hull more surface areato glue onto, not really for strenght. The hulls strong enough as it is....The top deck if you look, doesnt really have much to grab onto other than the tops of the bulkheads and stringers which are only 1/16". I will put the 1/8 strips along the tops of the sponson stringers and along the bottom joint between the sponson stringers and hull bottom meet instead of appying a bead of epoxy. I did however apply a bead of epoxy mixed w/micro balloons along the sponson bottom and stringer only between bulkheads 3&4, the riding area of the sponsons since that area of hydros. I've done that for years being a high stress area. I used CA and spray accellerator in the construction mostly...I will use 30min epoxy on the deck only because I want to weigh the hull down with some books while its setting to get the hull straight and avoid any twists. It sits straight for the most part, but I have a collection of those old white childrens encyopedias from the 70's laying around, they're outdated but they work great in getting models boats straight!
Today I recieved my "perfect" fuel tanks, good god are they tiny! beautiful little things....I'm waiting on my radio gear and my micro cox servos to come in before I commit to cutting holes for the water lines. I may put the tubes along the sides for a clean look and give me room to manuver my radio gear around easier, but like I said, I'm gonna wait for the rest to come in, and when I have everything I'm going to try different possitions and layouts, and weigh the hull on a scale. I'm trying to keep the balance correct before commiting to something first. Weight distribution is important in such a little boat..again I think the key in speed is 1. balance, 2. surface drive/prop. 3. weight. 4. rpm's out of your engine.
with a surface drive the engine will obtain more rpm's than being directly under the hull as in the plans. the angle of the hardshaft in the plans is anti-speed.
I'm tempted just to use a TD .09 now! I thinkthe TeeDee .09 is a better investment than the queen bee. In the meantime I have a TeeDee .051.
Jetpacks idea of laying the hull upside down for the deck is a great idea, as epoxy will pool down and the deck on the Atlas is for the most part flat, it will work..
i'm taking my time on these boats. They're gonna be awesome guys!
I still have a Dumas Thriftway and short stuff under the bed waiting for me.....
Today I recieved my "perfect" fuel tanks, good god are they tiny! beautiful little things....I'm waiting on my radio gear and my micro cox servos to come in before I commit to cutting holes for the water lines. I may put the tubes along the sides for a clean look and give me room to manuver my radio gear around easier, but like I said, I'm gonna wait for the rest to come in, and when I have everything I'm going to try different possitions and layouts, and weigh the hull on a scale. I'm trying to keep the balance correct before commiting to something first. Weight distribution is important in such a little boat..again I think the key in speed is 1. balance, 2. surface drive/prop. 3. weight. 4. rpm's out of your engine.
with a surface drive the engine will obtain more rpm's than being directly under the hull as in the plans. the angle of the hardshaft in the plans is anti-speed.
I'm tempted just to use a TD .09 now! I thinkthe TeeDee .09 is a better investment than the queen bee. In the meantime I have a TeeDee .051.
Jetpacks idea of laying the hull upside down for the deck is a great idea, as epoxy will pool down and the deck on the Atlas is for the most part flat, it will work..
i'm taking my time on these boats. They're gonna be awesome guys!
I still have a Dumas Thriftway and short stuff under the bed waiting for me.....
10-13-2009, 09:03 PM
#35
RE: Dumas 1/2A Atlas van lines build
RJ keep up the great posts! Glad you're sharing all this.
My Miss Thriftway and Atlas kit came today. The Atlas kit is just as I remember it. It is too bad the Atlas is a painted hull. The solid mahogany is beautiful in this one. The decks also of the Thriftway. The Thriftway cowl was trimmed but nothing past where it should be. I spent most of the time looking at the cowls and how they will be to make molds from.
The Thriftway kit has me really excited, even though all i have is the deck halves, cowl and tail fin. No instructions or anything below the deck for parts, but I can lay the deck and cowl out with the fin and finally get a good idea of the boat and it's great! I would like to detail this one like the other ones Chief added over in the 1/2A boat club thread.
What else is cool is both boats have single tail fins. They should look pretty good sitting together.
My Miss Thriftway and Atlas kit came today. The Atlas kit is just as I remember it. It is too bad the Atlas is a painted hull. The solid mahogany is beautiful in this one. The decks also of the Thriftway. The Thriftway cowl was trimmed but nothing past where it should be. I spent most of the time looking at the cowls and how they will be to make molds from.
The Thriftway kit has me really excited, even though all i have is the deck halves, cowl and tail fin. No instructions or anything below the deck for parts, but I can lay the deck and cowl out with the fin and finally get a good idea of the boat and it's great! I would like to detail this one like the other ones Chief added over in the 1/2A boat club thread.
What else is cool is both boats have single tail fins. They should look pretty good sitting together.
10-14-2009, 06:46 PM
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RE: Dumas 1/2A Atlas van lines build
I took a break today to work on my Dumas 36" atlas van lines U-76. Too bad Dumas didnt make a 18" version of this hull...Which got me thinking,
I do have several plans of the garry finlay boats, the '69 notre dame, a '77 atlas hull, baby bootlegger and the '80 pay n' pak....all of these can be scaled down to 18" I'm sure.
The '77 atlas van lines hull withchanging the cowls can cover about 14 different boats. Last time I built one of these it cost me about 36 bux for balsa sheets and a bottle of c/a over at my local Hobby Lobby....Hmmm, lots of ideas..
I do have several plans of the garry finlay boats, the '69 notre dame, a '77 atlas hull, baby bootlegger and the '80 pay n' pak....all of these can be scaled down to 18" I'm sure.
The '77 atlas van lines hull withchanging the cowls can cover about 14 different boats. Last time I built one of these it cost me about 36 bux for balsa sheets and a bottle of c/a over at my local Hobby Lobby....Hmmm, lots of ideas..
10-14-2009, 07:55 PM
#37
RE: Dumas 1/2A Atlas van lines build
RJ, if you want to do that, order plan set 108 from Newton Marine. It's a better design and if you want to shrink it, it will still work. All you would need to do is get color sheets of whatever boat you want to build in the 108 seiries and off you go. If you do't know the address, it's www.newtonmarine.com
10-16-2009, 01:03 AM
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RE: Dumas 1/2A Atlas van lines build
I have used the Cox TDee 051 in a heavy made (over built) small all ply rigger. I used the metal dumas 1x1 prop and set up the rigger for surface drive using the stock 049 dumas boat gear. I used a large skinny O ring for a belt to start the motor. My motor had aftermarket throttle muffler ring that allowed me to slow it up in the turns. I used a 1oz bottle tank and tapped off muffler pressure. Speed was approx 18 to 22mph. the high rpm motor ran well off 20% nitro. I used a small 200mah nicads for the radio and a micro servo of the day which weight was around a 14grams. The over built heavy rigger would run well only if the motors needle was set for max scream mod then backed off a hair for the bumps on the water. I then went with a queen bee as it was so nicely set up to idle and had muff presure. The queen bee made the rigger jump up into the mid 20's with less fuss for a perfect max needle setting. I really enjoyed the rpms of the 051 more and with today building skills and light weight gear and shrinking down modern rigger designs there is no reason you cant get 30mph. If you go with the 051 with the flexable nylon prop you will see some reasonble upper teens in speed. If you go with the 09 use a cut down X427 to X424 with half the tounge and star the prop tips sharpen and ballanced you may see close to 30mph with modern gear. I had to hand luanch the boat with the 051 wide open. And you couldnt ever back off more then 3/4 throttle without the risk of boggin down the motor. The queen bee had no problem pulling out of half throttle to full.
10-16-2009, 01:26 AM
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RE: Dumas 1/2A Atlas van lines build
Hey I dug out the boat .. now this thing is about 19yrs old. I will post some pics and I checked the weight minus batteries and rx gear. I recall using 4 AA now. lol geez the over all weight was sooo over kill on this motor. Today as you see it the wieght was just on 20 oz. I could have saved about 12oz with a modern boat will post one of my modern creations I would love to use the 051 with. 
It will have to wait I need to figure out how to post a image on here.
It will have to wait I need to figure out how to post a image on here.
10-16-2009, 01:51 AM
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RE: Dumas 1/2A Atlas van lines build
http://www.rcuniverse.com/gallery/ga...memid%3D127855
humm havent learned how to post a pic so here are the links to some pics.
Anyways looking forward seeing how your hydro turns out. I like the wood grain look in the kit just have to use some light weight filler for the grain and if all goes well you can keep the over all weight down.
10-16-2009, 02:14 PM
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RE: Dumas 1/2A Atlas van lines build
Hi Air mover welcome aboard!
What I do I on the upper right hand corner, click "reply" and to upload pics on the lower left side theres a link that says, " click here to upload images and files".
Other than that I appreciate your input on your past experiences. Thats pretty much what I've been thinking, keeping the RPM's up by using a surface drive should get some speed outa these lil' guy's.
Mr. HydroNut.
To the best of my knowledge the plans by garry finlay or at least some of them are scaled down versions of Roger Newtons plans. Or the color scemes or something like that... I'm almost finished with my dumas 36" atlas U-76. I do have a new in box Atlas 36" U-71 as my next big project....
Hey JetPack,
Give me a p.m. of your address so I can send you the templates of the Thriftway....I havent started tracing them yet but will start this weekend. I'll do the best I can I promise you on that. The mahogany that came with mine is in pretty good shape and surprisingly looks pretty sharp....Its a Ted Jones hull and it could be made into several other boats. A mahogany deck would look sharp. The plans which I'l copy also mention a o.k. cub marine .049. I've seen them and they look more functional that the cox babe bee. I like the idea of a pull start and built in fuel tank...
Now my atlas build is coming along well. Deck is still off as I'm waiting for my hardware to arrive, and a final desicion as to where to stick my fuel tank/s. I love the idea of building them so that the flow and filler tubes come thru the firewall or building them into the sponsons. So i'm waiting for all my gear to come in so I can lay everything out before I slap the deck on....
What I do I on the upper right hand corner, click "reply" and to upload pics on the lower left side theres a link that says, " click here to upload images and files".
Other than that I appreciate your input on your past experiences. Thats pretty much what I've been thinking, keeping the RPM's up by using a surface drive should get some speed outa these lil' guy's.
Mr. HydroNut.
To the best of my knowledge the plans by garry finlay or at least some of them are scaled down versions of Roger Newtons plans. Or the color scemes or something like that... I'm almost finished with my dumas 36" atlas U-76. I do have a new in box Atlas 36" U-71 as my next big project....
Hey JetPack,
Give me a p.m. of your address so I can send you the templates of the Thriftway....I havent started tracing them yet but will start this weekend. I'll do the best I can I promise you on that. The mahogany that came with mine is in pretty good shape and surprisingly looks pretty sharp....Its a Ted Jones hull and it could be made into several other boats. A mahogany deck would look sharp. The plans which I'l copy also mention a o.k. cub marine .049. I've seen them and they look more functional that the cox babe bee. I like the idea of a pull start and built in fuel tank...
Now my atlas build is coming along well. Deck is still off as I'm waiting for my hardware to arrive, and a final desicion as to where to stick my fuel tank/s. I love the idea of building them so that the flow and filler tubes come thru the firewall or building them into the sponsons. So i'm waiting for all my gear to come in so I can lay everything out before I slap the deck on....
10-16-2009, 05:57 PM
#42
RE: Dumas 1/2A Atlas van lines build
Air Mover swings in with some experience! It's great to see you show up and share what you know about these.
Those TeeDee's don't make any power unless they unload like you experienced. Cox racing fuel is 30% and I used to burn that. It really makes them come to life.
I started a Cox/Dumas 1/2A boat thread here at RCU, just follow the link to catch up on where we are at with this one.
I've always wondered how that QueenBee would do in a boat, now I know [8D]
[link=http://www.rcuniverse.com/forum/m_8498373/tm.htm]Dumas 1/2A Boat Club[/link]
There's quite a few varieties of the Miss Thriftway and also the Atlas. One that comes to mind right away is the Miss Madison.
Those TeeDee's don't make any power unless they unload like you experienced. Cox racing fuel is 30% and I used to burn that. It really makes them come to life.
I started a Cox/Dumas 1/2A boat thread here at RCU, just follow the link to catch up on where we are at with this one.
I've always wondered how that QueenBee would do in a boat, now I know [8D]
[link=http://www.rcuniverse.com/forum/m_8498373/tm.htm]Dumas 1/2A Boat Club[/link]
There's quite a few varieties of the Miss Thriftway and also the Atlas. One that comes to mind right away is the Miss Madison.
10-16-2009, 07:24 PM
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RE: Dumas 1/2A Atlas van lines build
The color scheme in the dumas instructions state that the U-60 Miss Thriftway was deck, sides, and fin are white. cowl is orange and the bottom is aluminum. then the decals that came with it are orange and white. The decals are close enough to the real boat....However alot of pics I see feature what appears to be either a mahogany deck or some shade of orange....However these pics came from here...http://www.missthriftway.com/
I cant wait to work on this one......
10-16-2009, 07:55 PM
#44
RE: Dumas 1/2A Atlas van lines build
Never knew they had a website. Cool!
I just finished scanning a 10 piece collection of 8x10 photos of some popular hydros which a couple of them offer a different sponsor for the Atlas and Thriftway type hulls.
Here's the Atlas, Miss Madison and Pizza Pete.
The Miss Thriftway could fit in with the Sunny Jim.
I want to look into changing a Thriftway to a stepped deck / dropped sponson design. I think it would only require shaping the top of the sponson bulkheads to do it.
Chrome Modeler's foil on the bottom of the Thriftway would be a challenge to do to get a nice looking hull but it would be worth it.
I just finished scanning a 10 piece collection of 8x10 photos of some popular hydros which a couple of them offer a different sponsor for the Atlas and Thriftway type hulls.
Here's the Atlas, Miss Madison and Pizza Pete.
The Miss Thriftway could fit in with the Sunny Jim.
I want to look into changing a Thriftway to a stepped deck / dropped sponson design. I think it would only require shaping the top of the sponson bulkheads to do it.
Chrome Modeler's foil on the bottom of the Thriftway would be a challenge to do to get a nice looking hull but it would be worth it.
10-16-2009, 08:51 PM
#45
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RE: Dumas 1/2A Atlas van lines build
Chrome foil isnt a challenge at all......i use that 3M spray glue and use that to laminate the foil to the wood....Also another neat product is Welders contact cement...both are at Home depot.
I used the contact cement to attach the top decks of my red 1/16 scale hydro. Just spread it completely on the underside of the deck to seal the wood and then run a bead on the tops of the frames/bulkheads. Let it sit for about 10-15 minutes then CAREFULLY apply the deck. once its in place its ON. No problems in the 3 years its been running.
I used the 3M spray in a similar fashion. I used it to laminate 1/32 ply over 3/32 balsa to strengthen the hull..Spray both pieces and let sit for about 15-20 min. then attach....
I dont see why it wouldnt work on these little boats. Thats why I was thinking about scratch building a scaled down version of a boat from Roger Newton's plans or the garry finlays plans that I have.....I would use 1/16 ply for the sponson transom and sponson/stringers to start. and the rest out of 3/32 balsa....maybe skin it with 1/32 ply.
It should be very light and strong.....
Heres a great secret.....I use my wifes iron (she doesnt know....Shhhhh) And spray alittle water on my sponson side skins and pull and shape the skins with the iron to form a curve in them that matches the curve of the sponsons.....It works great on balsa and 1/16 ply too!
Honestly though, these dumas boats are so small that its not really necessary to iron out your parts.....unless you have an old kit laying around and the wood has small warps in it.....Iron them out on a flat 1x6...
btw, no starch.....
I used the contact cement to attach the top decks of my red 1/16 scale hydro. Just spread it completely on the underside of the deck to seal the wood and then run a bead on the tops of the frames/bulkheads. Let it sit for about 10-15 minutes then CAREFULLY apply the deck. once its in place its ON. No problems in the 3 years its been running.
I used the 3M spray in a similar fashion. I used it to laminate 1/32 ply over 3/32 balsa to strengthen the hull..Spray both pieces and let sit for about 15-20 min. then attach....
I dont see why it wouldnt work on these little boats. Thats why I was thinking about scratch building a scaled down version of a boat from Roger Newton's plans or the garry finlays plans that I have.....I would use 1/16 ply for the sponson transom and sponson/stringers to start. and the rest out of 3/32 balsa....maybe skin it with 1/32 ply.
It should be very light and strong.....
Heres a great secret.....I use my wifes iron (she doesnt know....Shhhhh) And spray alittle water on my sponson side skins and pull and shape the skins with the iron to form a curve in them that matches the curve of the sponsons.....It works great on balsa and 1/16 ply too!
Honestly though, these dumas boats are so small that its not really necessary to iron out your parts.....unless you have an old kit laying around and the wood has small warps in it.....Iron them out on a flat 1x6...
btw, no starch.....
10-16-2009, 08:58 PM
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RE: Dumas 1/2A Atlas van lines build
forgot to add these, sorry....
The dumas miss thriftway is a ted jones hull and heres a few, I'm sure theres more....
1957 Hawaii kai
Maverick
Shanty
Wahoo
Gale VI
Miss Seattle
Next thing is to find tiny drivers for them. smallest I found were 1/16 scale from http://www.drcwebservices.com/ffe/
check out the scale accessories link......alittle too big for our boats but its a start if anyone wishes to build a slightly bigger version
The dumas miss thriftway is a ted jones hull and heres a few, I'm sure theres more....
1957 Hawaii kai
Maverick
Shanty
Wahoo
Gale VI
Miss Seattle
Next thing is to find tiny drivers for them. smallest I found were 1/16 scale from http://www.drcwebservices.com/ffe/
check out the scale accessories link......alittle too big for our boats but its a start if anyone wishes to build a slightly bigger version
10-16-2009, 10:53 PM
#47
RE: Dumas 1/2A Atlas van lines build
These could be pictures of the replica 1955(?) Miss Thriftway. The original boat had a mahogany deck that was painted brown after the boat was damaged. It was replaced in 1958 and then again in 1960 if I remember right.
As a side note, I just looked at a set of Gary Finlay's plans for a round nosed boat. I find there are only a few things in common with Newton plans, so I feel they weren't redone scale plans.
As a side note, I just looked at a set of Gary Finlay's plans for a round nosed boat. I find there are only a few things in common with Newton plans, so I feel they weren't redone scale plans.
10-19-2009, 03:24 PM
#49
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RE: Dumas 1/2A Atlas van lines build
Nothing new yets guys, still waiting on my hardware and servos to come in. In the meantime I'm working on finishing my 36" Atlas U-76. I'm open to suggestions on how to seal and finish the outside wood. What I've done was to use a finishing resin and sqee gee it on. then sand and apply primer.
While we're waiting on my parts for my mini Atlas, heres a background of my R/C experience
I started to build models back in the mid 70's and @ my school we had a model building contest and I won first place! both years '76 & '77! I was 8-9 yrs old. As I got older I use to cut grass for some of the neigborhood seniors during summer vacation and I spent my money at the local hobby store buying mostly estes model rockets and small dumas boats, one of them was this same 18" atlas, this was 1983. In 1988 I became involved with the Timberlake Amp Eaters fast electric boat club, I was club secretary. We organized IMPBA sanctioned races around the western chicago area. Most of my electric boats were MRP Mr. Pringles set up with a Hughey duel gear drive swinging a X442 prop and a few electric thunder shovel nose hydros with astroflight 05's direct drive.
I started to experiment with direct drive setups around the early 90's but still remained loyal to the hughey gear drive since that was the hottest setup at that time. Ed's boats were among the fastest I've seen at that time among a few others. My Dumas boats I built over the years include 2 1/8 scale hydro's a Pay n pak and a Miller American. a hot shot 45, 17" sloop sail boat, alcort sunfish which was my favorite sailboat, sailed it from '82 thru 2002. Love to build another one. a 12" cabin cruiser. hot shot sprint 3.5 converted to electric inboard. drag n fly 40, pay n pak 20, atlas U-71 & U-76. Short stuff & miss thriftway. and I scratch built several 1/16 hydros....Man, i love my hobby.
While we're waiting on my parts for my mini Atlas, heres a background of my R/C experience
I started to build models back in the mid 70's and @ my school we had a model building contest and I won first place! both years '76 & '77! I was 8-9 yrs old. As I got older I use to cut grass for some of the neigborhood seniors during summer vacation and I spent my money at the local hobby store buying mostly estes model rockets and small dumas boats, one of them was this same 18" atlas, this was 1983. In 1988 I became involved with the Timberlake Amp Eaters fast electric boat club, I was club secretary. We organized IMPBA sanctioned races around the western chicago area. Most of my electric boats were MRP Mr. Pringles set up with a Hughey duel gear drive swinging a X442 prop and a few electric thunder shovel nose hydros with astroflight 05's direct drive.
I started to experiment with direct drive setups around the early 90's but still remained loyal to the hughey gear drive since that was the hottest setup at that time. Ed's boats were among the fastest I've seen at that time among a few others. My Dumas boats I built over the years include 2 1/8 scale hydro's a Pay n pak and a Miller American. a hot shot 45, 17" sloop sail boat, alcort sunfish which was my favorite sailboat, sailed it from '82 thru 2002. Love to build another one. a 12" cabin cruiser. hot shot sprint 3.5 converted to electric inboard. drag n fly 40, pay n pak 20, atlas U-71 & U-76. Short stuff & miss thriftway. and I scratch built several 1/16 hydros....Man, i love my hobby.
10-19-2009, 03:57 PM
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RE: Dumas 1/2A Atlas van lines build
New but old hydro, I recently received an old MODEL BOATING WORLD NEWS DATED SEPT 1968 it has a LITTLE HUGHEY .19 POWERD HYDRO BLUE PRINTS also part 2 OCT 68 .The hull is 24"x12 1/2 " the prints are to scale.I f any one wants a small hydro sent me a PM I will mail you a copy nice little build. my copier is a little small .How did we receive the JAP .12 FREE PLANS? It was a download I think But how??? A trip to Staples will have to do I don't have auto cad installed. The fuel tank is a home build made out of a 4 1/2 oz .liter fluid can. The mount made out of 3/16 fiberboard.