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Old 10-06-2009, 08:47 PM
  #51  
R.J. West
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Default RE: 1/2A Size Boat Club

Hey Jetpack,
congrats on your find, now I see who my competition was on bidding for those two boats [img]/forum/js/punymce/plugins/emoticons/img/trans.gif[/img]
Today I made cutouts on the stringers and bulkheads using my dremel on the atlas. While the build was coming together I did notice the weight ganing. The cutouts made a big difference.
I saw those boats you won, and I kept looking, and I found a complete Thriftway for a buy it now price of $60, so I took it. I'm also stocked up on Medallions .049's including a medallion 51 and a medallion r/c .049. The r/c has a C-clip ring thing around the cylinder, is that for throttle control? I stocked up on medallion's because they were more affordable than the Tee-dee's.
Now I do havethe cool clamp from dumas and a cox buggy heatsink. I;m gonna try the cooling clamp first.
Heres some pics, one is my 1/16 scale hydro scratch built from garry finlays plans for the '69 notre dame. cost me 36 bux from hobby lobby for the wood, all 3/32 balsa.
I was thinking about sticking in a Tee-dee .09 in this one just to see what happens. The hardware is also built from his plans. This is the wire drive I was thinking of using. Its K&S stainless steel 1/8 O.D shaft that will allow a 1/16 wire to pass thru. set screws hold it all together. Shafts for penny's....




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Old 10-06-2009, 08:55 PM
  #52  
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Default RE: 1/2A Size Boat Club

I dont know why my post looks so ulgy? sorry folks, new to this ya know.......
Old 10-06-2009, 11:28 PM
  #53  
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Default RE: 1/2A Size Boat Club

If you mean the large picture size when it's loading mine does that too but it will fix itself in a day or so.

I've wanted a clean copy of an Atlas 18" for well over a couple years now, and been watching auctions. They usually go for $50-$80 and the Miss Thriftway for slightly more.

Something happened to one of the bidders dropping out after discovering the Miss Thriftway was missing parts after I had asked for more pics of the sheets, so the bidding dropped to half of where it was at, and guess everyone that was involved forgot about it and never returned to discover that happening. Sweet deal for me though. Two clean vintage kits for less than the price of one. I guess perseverance does pay off. Makes up for all the times I've got jammed.

Now the only hole I see now in the collection is the Miss Thriftway II cabover, and a couple others such as a copy of your Deep V which can still be had.

I'm going to try an 09 in the SkeeVee 10 kit I have and use the machined outdrive from The River specialists. I have to be able to hear the 09's run. Harrowing sound. Loudest little engine you'll ever hear. There's a story here where a flyer brought his 09 to the field one busy day. He set up and went to fly nobody really ever giving him a glance because of it being a small plane. He fired it up and froze everyone there in their place that was there. Sounds like a blast to me.

Everything is so critical on getting good speed out of these boats. You should look into getting a metal prop from Dumas you could play around with. I'm going to see how a stock one that is thinned out does first. Then I'll be able to shave it down if it needs it or hopefully be able to cup it a little. I would like to try tuning props with these, part of the fun.

The plastic prop which you have will do just fine. I believe it is the same size and pitch as the metal JG prop which I think is also the same as the O&R 1". That is the one I had on mine and it did well. If you do not intend to thin, balance and sharpen the copper props, the plastic injected molded one will be the best. It was more than likely a CNC cut mold which are very accurate. However, you are stuck with what they give you. The metal ones let you shape past the performance of the plastic. I HOPE.


It did seem to be a little bit under pitch but the diameter seemed right. Of course it was battling the negetive solild strut that you also have, also. Adjustable is the only way to fly here. Can't wait to attempt bringing the prop out of the water a little on them with the larger ones I have. The power and rpm is there but the prop selection is hurting. There might be some plastic or carbon ones that electrics use that might fill the gap, but then your trapped with their metric hardware that has to go along with it. TeeDee's do not like heavy loads. They like light loads and really high rpm's. That strut angle with the solid setup won't ever allow that to happen to get where the true power is on a TeeDee.

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Old 10-07-2009, 12:46 PM
  #54  
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Default RE: 1/2A Size Boat Club

Jetpack & RJ you can still get those hulls from Dumas you need to call not on internet http://www.dumasestore.com/catalog/index.php
1-800-458-2828
Old 10-07-2009, 04:22 PM
  #55  
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Default RE: 1/2A Size Boat Club

Hi Advanced, Thanks for the number. I just called and the lady said they haven't any more and doesn't think they will ever be made again. I asked about cowls and decals too, same answer. The Miss Thriftway Too is also gone away.

I know what you mean though about calling because when I bought my Drag 'N Fly 40 kit they had it in stock but not listed in their catalog, so you never know sometimes.

She said they wont be making any more small (18") kits anymore so grab whats left I guess.
Old 10-07-2009, 05:04 PM
  #56  
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Default RE: 1/2A Size Boat Club

o.k. you got me.

Well I'm very glad you got your boats. I was very lucky to come accross that Thriftway at a buy it now price of 60 bux. 

Just got my drag n' fly from Dumas about  a week or so after I ordered it online.....build that one over the winter, looks like a really cool boat! I like the design...

Now jetpack, I like you collection of parts in that pic, almost looks like what I have, except mine are medallion .049's. One of mine has a silver cylinder w/ 2 slots on each side and I dont think its stock, looks like a performance upgrade. and the other 3 are new in the box....and of course my rebuilt babe bee .049....I also bought a bunch of the cox mini servos....tiny little guys....
But yeah, I know the key to getting these boats to speed is the angle of the driveshaft.  I have an octura x427 & x430. I do have the plastic dumas prop, but need to get some more. I'll try the dumas jg-1.
I saw on ebay a NIB TeeDee .09, dont know if its still there or not, should be. But a TD .09 in a 18" boat should move....

Heres a recap of my lil' boats.....Dumas 18" atlas (almost done)
Short stuff 18"
Thriftway 18"
Scratch built 22" 1/16 scale hull w/ old electric thunder cowl (remember those?)

My medallions need a fuel tank, what size would you reconmend?. They appear to have a vacum nipple on the screw side of the carb, I assume the nipple opposite of the needle is fuel inlet....


as soon as I get my Thriftway i can pm you if you would like a copy of the templates....
Old 10-07-2009, 05:33 PM
  #57  
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Default RE: 1/2A Size Boat Club

Yes, I was really shocked how the auction happened. Both kits I've wanted for a long time come up together and get them that cheap. Now that's a freaker. I jumped up and hollered when I won.

That cylinder you have with the double slits is a later style of cylinder, usually found on the Sure Start varieties. The TeeDee's and Medallions never had them so that means someone switched them over at sometime. I'll do some homework for you on the cylinder types. I have a chart I'll post. The only way you can tell what you have is to unscrew the cylinder and look at the ports that are milled in the sides. There's like four kinds, all have different power and such.

Which Drag 'N Fly did you decide on? I'm thinking the little 20 picklefork? Sounds good on the templates for the Thriftway. My package shows shipped so it should be here soon too.

The Medallions and the TeeDee's all have a nipple on the plastic intake housing. If one wanted to run a pressure system, these holes are drilled through with it off, then put back on, and then you start the drill again and finish the hole with the plastic off.

The pressure that is put out is not much, almost like running a line from a muffler. A true pressure system uses a nipple in the backplate. You can split a tank with the pressure that comes out of it, and the only way to regulate it is with a special fine thread aftermarket needle now almost extinct.

I ran a Perfect Brand 3/4oz metal tank in my Atlas. It was a rectangular type and sat flush with the deck mounted flat on the bottom of the boat. Just before I launched I would add fuel to top it off to recover any lost in trying to start it. I was able to use the stopwatch on each run and depending on how the needle was set, I was getting 6-8 minute runs. I would time my runs so I could get an idea how good I was guessing at the needle setting. The 8 minute runs were getting too much towards a lean, hot run and it showed me I should try richer settings again. If I ran a six minute tank I noticed better engine temps but also a little less speed.
Old 10-07-2009, 09:26 PM
  #58  
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Default RE: 1/2A Size Boat Club

What a shock with the Dumas hulls. Say it ain't so. I guess you can still get there running Hardware . If you want LOL
Old 10-07-2009, 09:38 PM
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Default RE: 1/2A Size Boat Club

Ok thanks for the info, I'll go ahead and see if I can grab myself one of those perfect tanks...
The Drag 'N fly I chose was the .40 size. What I've been doing was looking at the discounted boats on the Dumas website. I wasnt aware of the .20 size and I havent gotten my catalog yet.
  I took the head off and the back plate, needle screw and spring and hosed the engine inside and out w/ wd-40 and it cleaned up pretty nice, and now it turns over very easily. I tried bidding on a new cylinder & piston for a medallion .049 but lost out by .50 cents! But I will replace it when I can...
I do have the original instrurtions for my engines and it explains about the pre drilled (starter hole) in the back plate if one wishes to get some presure that way...I'll try it on one of my engines to get some presure in the fuel tank.
Other than that, theres lots of parts online and performance upgrades for these little guys....
Old 10-08-2009, 05:53 AM
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Default RE: 1/2A Size Boat Club

Here's a page that has a metal 3/4oz tank. [link=http://www.brodak.com/shop.php?pageNum_ProductInfo=4&totalRows_ProductInfo=200&CategoryID=245]Brodak Manufacturing[/link] is big into 1/2A control line kits, their own engines, and building supplies.

I think the tank is the same as the old Perfect Brand tank.
Old 10-08-2009, 12:21 PM
  #61  
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Default RE: 1/2A Size Boat Club

Thanks for the info....looks good.
 What do you think of their engines? Seems like they'l work in these boats...
Old 10-08-2009, 12:32 PM
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Default RE: 1/2A Size Boat Club

Guess you guys are going to make me breakout my old CAD file of a small 18" outrigger I named "Problem Child" and stick one of my Mangusta DR .049's in it just for fun and laughs. Maybe I'll redraw the CAD file for my own hardware and fire up my milling machine.
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Old 10-16-2009, 07:07 PM
  #63  
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Default RE: 1/2A Size Boat Club

This is all looking great anyone have any video ? [8D]
Old 10-16-2009, 07:12 PM
  #64  
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Default RE: 1/2A Size Boat Club

The wide one is a old build about 19yrs ago the skinny rigger is a 5yr old rigger Im thinking on using to see what kind of speeds I can get with modern light rc gear. Weights are 1.25 lbs for the old rigger as shown and 5.8oz with the new rigger. What kind of speeds are you guys getting?
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Old 10-18-2009, 01:54 AM
  #65  
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Default RE: 1/2A Size Boat Club



This has a nice exaust throttle and the rigger is small enough to runclose tohalf throttle and not bog down. 7.6oz all up minus 1 oz tank of fuel.

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Old 10-18-2009, 08:10 AM
  #66  
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Default RE: 1/2A Size Boat Club

nice looking rigger,Air Mover I hope the air you move is safe to breathe 7.6 oz thats lite
Old 10-18-2009, 08:29 AM
  #67  
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Default RE: 1/2A Size Boat Club

Especially when these engines are used to pulling around a 20 ounce plane.

That's a great effort you put into the riggers to get the engine to work.

I would like to see more pics of the machined exhaust.

Is the prop soldered onto the propshaft or are you using threads? It's hard comming up with a streamlined strut without making custom with these. Is that the Dumas metal prop?

I see your using a five fin texaco head too. How about the flywheel?
Old 10-18-2009, 10:57 PM
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Default RE: 1/2A Size Boat Club

Ihave kept itliteby using 4.4g servo's (isolated mountusing fuel tubing between the servo and rail). 5.6g rx1S 240mahlipo'sfor the servo's. Thin ply hual and 3mm carbon tube booms. All up weight is 7.58oz plus 1oz of fuel. I use a Ed Hugey aluminum coupler with 1/8 flex drive lowers weight. I dont like using the dumas universal joint its heavy and clunky causeing wobble wear to a nonbearing engine.The dumas props where moded for a drive dog and everything is flush to the stuffing box tube.

Here are some pics of the muffler about 21yrs old and works great by rotating the pipewith a control arm and has a tap for fuel pressure. Less goo in the hual with this diversion but doessapsome top end.

I moded the dumas props for drive dogs. Here is a close up of a self made 2020 prop with a 2mm IDhub.

What sort of weights are you seeing with your 1/2A boats?

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Old 10-19-2009, 01:42 AM
  #69  
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Default RE: 1/2A Size Boat Club



Pics.

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Old 10-22-2009, 02:01 AM
  #70  
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Default RE: 1/2A Size Boat Club

http://www.americanjuniorclassics.com/movies/Boats.wmv

Found this lovely treat of small 1cc motor which isthedisplacement of an049 is powering Jim Walkers Miss Thriftway .
Was neat to see the prop bite and the lil hydrotake off.Wasgood fun to seethe young lad all set n ready, heart beating a mile a min.


Hereare somevintage pics of two other guys and there boats. Looks like there same size as dumas hydros perhaps the one of them is?
The old hydro in the shop became mymonitor's background, this one just makes ya want to build something huh ..
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Old 10-22-2009, 01:32 PM
  #71  
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Default RE: 1/2A Size Boat Club

Call me OldSchool, but the pic on the right reminds me of when a hobby was just that...a hobby. NothingMOVES me more than building something from scratch, and saying "look at what I made". Buying something off the shelf thats RTR in my opinion dosnt quite fit the description of "hobby". More like an expensive "toy".
Old 10-22-2009, 06:43 PM
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Default RE: 1/2A Size Boat Club

Absolutely spot on with that.. these guys back then where considered model boat engineers as they had to make almost everything from scratch. Lots of idea's for the futureand what they actually made from scratchhelp build theearly model product lines. Today this market is still driven by mold breakers. I hope to blend the old with the new and so enjoy the Dumas vintage gear, boatsalong with the classic cox motors and the custom productsfor those engines. My efforts are to strive for betterspeeds, performance and reliability. I had the short stuff mono on a 049 back in the day. I now have plans, some from dumas and othervintage hydro's so looking forward to posting more efforts here.


Ok looks like Ihave learned the vintage hydros where Jim Walker designs perhaps Dumas kept the work going after A-J co. was sold. Im searching for Dumas history of boats so anyone land some sites please post your links.
This is what I had found.
Recently the A. J. line was broadened to include boat kits. The first model to capture the fancy of the modelers was the "Miss Thriftway," a replica of the unlimited hydroplane that has captured the Gold Cup for the past three years.
The 18-inch model is designed for display or use with 1/2-A or small-A class motors. Miss Thriftway sells for $2.95 for boat only and $10.95 for boat and Firecracker engine and $11.50 for the boat and Cub marine engine and hardware. A marine hardware kit has also been introduced at 98 cents and includes prop, universal, strut, shaft, stuffing box, rudder and rudder brackets for small engines.
Old 10-22-2009, 07:49 PM
  #73  
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Default RE: 1/2A Size Boat Club

One thing I am surely going to try out is my own scaled down Drag N' Fly .049
Old 10-22-2009, 09:24 PM
  #74  
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Default RE: 1/2A Size Boat Club

I think a scaled down drag n fly would be cool!
Heres my Dumas 18" boats to date:
Atlas vanlines
Miss Thriftway
short Stuff
I did alittle research on the Thriftway Too cabover design, and I agree that it was ahead of its time. Awesome looking boat....And I dont know if Dumas made a 18" version of it or not, but if someone has plans or templates for a 24" dumas Thriftway too give me a hollar.
Also I believe the U-60 Thriftway (18" version) is based on the 1963 boat, which was all white and orange stripes with aluminum sponson sides and bottom. I'm going by what the instructions say in my miss thriftway kit....
The boats missing in my growing .049 collection are the Ski Daddle jr. and the Ski V-10. Let me know if theres others...
I uploaded the latest pics of my atlas build....
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Old 10-22-2009, 09:25 PM
  #75  
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Default RE: 1/2A Size Boat Club

Guys, this is a really cool thread! I had on of the blue metalflake SeeBee's when i was a kid...wish I still had it!

It doesn't really apply for this subject, but I wanted to mention that Novarossi has a .09 engine configured like a TD, Norvel etc. Not sure of the price, but I think I could sell them for $70 - $80

You can find a picture and specs here: http://www.novarossi.it/eng/products...1.09&brand=rex

Glenn


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