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Building the R-Geo Shark F1 (update: newest version tested)


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#1 JimF

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Posted 12 April 2016 - 01:05 PM

Starting up a new F1 build today with some components from R-Geo. I have been messing with these for a while and have built up several variations. This will be a fairly standard variation but with a rail configuration that I have yet to try with these parts.

 

Below is what you’ll get if you order a “Shark” F1 kit from Rick. There are variations but this is what I got. Nosepiece, bracket, and bracket brace are all .050" brass. Pans and center weight are .062" brass. Steel guide reinforcer is (I think) .032".

 

1-Shark1%20001_zpswjst02rf.jpg

 

First step is always to detail your bracket. If needed, sand the bracket face flat. Then, check the bracket legs for square to the face. Finally, screw in the motor, slip in your bearings and axle/jig wheels, and check that it all lines up.

 

1-Shark1%20002_zpssdpupndh.jpg

 

In this view, you can see that this is an angled face bracket. This means that the bracket face is tilted to line up the motor shaft on center to the axle. In the past, I have been using hypoid brackets and I had not paid much attention to this type of bracket. I have to say that now that I’ve used these, I’m sold on the greatly improved gear mesh that these allow.

 

As an example, in testing something a month or so ago, I took a motor and gear set out of a normal hypoid car and placed them in one of these. The mesh was fine in the hypoid car but the set up gave a little of that mild “clashy” sound that so many Retro cars exhibit unless set up from the start with brand new gears. When I placed that motor/gear set in the angled bracket car, the gears quieted down to a whisper… I was impressed.

 

You can also see that this bracket has little undercuts right at the junction between the face and the legs. This allows you to tuck a rail or maybe two into this little pocket and get a few more rails in place inboard of the 'normal' ¾” bracket width. I have built a couple of these with seven rails/side of .039". I ran five rails outside and two more inside and was able to get the seven rails in place without going too wide for the pans to fit.

 

1-Shark1%20004_zpsqdb21tjd.jpg

 

OK... into the Jig we go to line everything up and set our spacing, etc.

 

1-Shark1%20005_zpsbmrmodzk.jpg

 

Getting going now. This is going to be four per side of .047" wire. The notches in the nose also accept the classic three x .063" and with a file stroke or two, five x .039". This nose just makes F1 building a breeze with about any rail configuration you want. In this case, I cut my rails, set them up as a pre-fab unit, and tack soldered at both ends. Then I dropped them in place and lightly soldered at the rear of the bracket and the front of the notch in the nose. If this was to be soldered full length, I would flow solder the rail sets and then clean them up before dropping in place.

 

1-Shark1%20006_zpsqd62ehck.jpg

 

Once the main rail groups are in place, it's a good time to check that your bracket face is square to the chassis. I place the mini square as shown here and check that it's square. No micrometers were injured or endangered during this build but it is a good idea to check square and flat from time to time.

 

1-Shark1%20007_zpsr4fl78yp.jpg

 

In this case, the main rails will not be full length soldered so take care not to get too much leakage of solder past your connection points. Here’s how I did this.

 

You can see some ink marks defining where I want the solder to go. These are at the bracket face, the area for the crosspiece tubes, and the also at the nose. I place little bits of notebook paper between the rails, flux up just the area where I want the solder and then solder it quickly with a hot iron. While I’m at it, the crosspiece tube go in place along with a little bit of wire behind to reinforce the joint and these are soldered up as well.

 

1-shark1%20008_zpsso1krf5m.jpg

 

1-shark1%20009_zpsezan9pyi.jpg

 

1-shark1%20010_zpslnkoplqm.jpg

 

Here, the excess of the crosspiece is trimmed out, the bracket is soldered full to about 1/8” forward of the bracket face, and also a small bit of .055" wire goes in place as a gusset between the bracket leg and the rails. The same is done at the nose, again using the paper to prevent solder from leaking down the rails. At this point, our center section/main rail assembly is completed.

 

1-shark1%20011_zpsyeydhdlv.jpg

 

 

OK… next up is fitting the pans. Here, I have trimmed the front of the near side pan and trimmed the little overhang of the bracket plate. In this case, I’m using the classic full length pan setup, but of course, there are any number of ways to do this. The pan on the far side and the little tail of the bracket plate are shaded for cutting.

 

1-001_zpslrzyymgo.jpg

 

OK… pans are cut to size. Next up are the shaker tubes. In front, I have two bits of 3/32” box tube getting ready to go in place. There’s a piece of 1/16” aluminum tubing holding them in alignment. The shallow U-shaped piece off to the side is a spreader bar that will tie the pans together in front. At the rear, we do the same thing except I used one bit of tubing centered on the bracket plate. Spreader bars at both front and rear are .047" wire but could be about anything.

 

Important to note that you could eliminate the spreader bar by making the shaker rods one piece and bending to fit in place after inserting through the tubes. That works fine but is a fiddley process and so I use the spreader bars and make the shaker rods two piece for ease in bending.

 

1-002_zpsmyjypubp.jpg

 

This pic shows the pans in place and soldered together at front via the spreader bar. There is a piece of notebook paper in place between the rails and the pans to provide a small amount of spacing and to keep the solder from going to the wrong places. At the rear, you can see the single shaker tube in place, the spreader bar ready to go in place, and the shaker rods. The far shaker rod is already in place, the near one is set to go in. The shaker rods are .047" wire. 

 

1-005_zpspaldcp5n.jpg

 

Here is the rear end finished up. Shaker rods in place and soldered and then the rear spreader bar in place and soldered.

 

1-006_zpsoupgpcbx.jpg

 

The next two pics show the nose ready to go. First one shows the shaker rods ready to place and the second pic shows them finished up. The tiny little bit of box tube in the center is the front retaining stop for the center weight. Believe it or not, we’re all done but for some little details.

 

1-007_zpssa65wjfn.jpg

 

1-008_zpsazeqqgyq.jpg

 

Here it is finished up. The guide tongue reinforcer is soldered in place, front axle is installed, and the center weight is hung. The center weight here is 1/16” brass and goes about 14 grams or so. This will give us a finished weight of about 113 grams all up with body. If you want lighter, you can make the center weight out of thinner brass or leave it out completely. The center weight is soldered to the 1/16” crosspiece which is free in the crosspiece tubes. The front stop is .047" wire.

 

In general, all movement parameters on this chassis are pretty minimal. I very much prefer body clips on F1 cars whenever practical but of course, pin tubes can easily be added.

 

1-003_zpslngz3po5.jpg

 

This frame will get tested on a speedway with a Retro Hawk and on a technical flat track with a Mini Brute. The unsoldered main rails will then be flow soldered and the tests repeated.   


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Jim Fowler




#2 Tim Neja

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Posted 12 April 2016 - 01:35 PM

Beautiful work, Jim!! Love how you show the steps to your builds!!   :)


She's real fine, my 409!!!

#3 Rick

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Posted 12 April 2016 - 04:01 PM

Thanks, Jim. Article is over the top and I have several builders/racers waiting for this. Knocked it out of the park again!

 

This style of build has become quite contemporary today and appears to win its share of podiums. Looking forward to the test results, especially open rails vs solid rails...


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#4 Dennis David

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Posted 12 April 2016 - 04:46 PM

Yep, me, too.


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#5 Eddie Fleming

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Posted 13 April 2016 - 06:08 AM

One thing bothers me about this build.

 

At every stage it looks like it just came out of a tumbler.

 

Beautiful work.  :clapping:


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#6 Tom Thumb Hobbies

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Posted 13 April 2016 - 09:13 AM

Very, very nice!

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#7 JimF

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Posted 13 April 2016 - 10:25 AM

One thing bothers me about this build.
 
At every stage it looks like it just came out of a tumbler.
 
Beautiful work.  :clapping:

 
Thanks very much, Eddie.
 
Generally, I don't tumble until the end but I do clean periodically during the course of a build. That is so that I can examine the solder joints as I go along.

In the case of article cars, I usually clean before I take a photo so that flux gunk doesn't obscure what is being done. Usually, this just involves scrubbing with a brass brush and Comet or dish soap. I also try to sano up solder joints as I go along.
 
I'm a lot more anal about cleaning for articles and also for customer cars than I am with general experiments and personal stuff.
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#8 JimF

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Posted 13 April 2016 - 10:49 AM

Here's a pic of the first test set-up. This is for a very technical flat track. Assuming the creek don't rise, this will get tested today. This is 108 grams as seen here and I suspect will be too light... but that's OK... I gots lead.
 
1-DJ%20003_zpsdsxgtklw.jpg
 
I suspect that full soldered vs unsoldered won't make much difference on the flat track. In general I full solder everything and always have. The one exception is Samson rail frames which I leave unsoldered. This will be an interesting comparison to a bunch of other rail configurations that I currently have.
 
After this is done, then I'll do the full solder comparison. What I'll do is dress it up in speedway trim with a Hawk Retro and test and tune it as shown. Then I'll solder it up right at the raceway and go right back to the track. That will take time that I won't have today because I'll be doing race prep and also testing a couple of customer cars. I'll have to wait a week or so before I do that final test.


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#9 Mark Johnson

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Posted 13 April 2016 - 12:58 PM

Dandy!!



#10 JimF

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Posted 14 April 2016 - 02:31 PM

Here's the first on track test. Testing was done on the very technical Motherlode flat track @ Eddies Slot Car World in Vallejo Ca. Conditions were....good bite but poor braid conditions in spots.This test was done with three other very good flat track cars all with different rail layouts.

 

As shown above, the car came in at 112 all up and as I suspected, was too light. The initial test was done stock, but I quickly added a substantial chunk of 1/16" lead on the center pan. This immediately made the car competitive. After testing that, I trimmed the lead and left some on the center block and took some of the rest and put it on the rear frame rails on either side of the motor. The center block goes about 5 gr. and the two side strips about 1.8 gr. ea. The amount of weight was the same but the car was much better with this weight distribution. At this point, it became my second fastest car on this track and this day.

 

8166cb38-6908-49e6-8958-b7c27eab928b_zps

 

I think that I made two mistakes in the setup for this car. One......I picked a motor at random and and inadvertently left the 9t pinion on it. I almost always run an 8t on this track and this probably hurt the tuning process. I also used a Parm Matra body that was mounted low whick is my normal process. I usually find that with the rear wing being lower, it lets the car move around a bit better in the twistier bits. However, this track, this day, my fastest car had the rear of the body mounted higher and I think this also might improve this car as well.

 

Here is a look at four different rail layouts (three on Shark Noses) These are all very good but somewhat different. L-R (most flex > least).

 

1-shark%20dvelopment%20004_zpsbziawl57.j

 

#1  7 rails/side of .039. The most twist flex and the most bite. Very smooth and stable car. Since I built this, it has been my fastest car. Today was the first time that this car has not been my fastest.

 

#2  New Shark, 4 X 047 unsoldered. This is similar in flex to the next one. This was my #2 fastest today. This chassis has a lot of energy or snap on turn exit. This feels really quick but a little demanding for this track. I think this might also be a gearing issue.

 

#3  Hybrid rail. Sandwich of .047 wire abound flat brass strip. Approx, same flex as the New Shark. This was my fastest car today by a solid 1.5 tenths. Probably largely b/c of having quite a bit of development time on it.

 

#4  Samson rail (unsoldered). Have had this car for some time now and it is maybe the F-1 equivelant of the "No Brainer" Can Am car.

 

Although all these cars weigh about the same, and all are 4 1/8" WB & 1.0" guide lead, most have a little more nose weight bias than the #2 New Shark. The new shark will be going with me to our race this weekend and it will have lower gearing, a little more nose weight bias and a tall-tail body on board. This was a realy good first test and with a little tuning, I may race it this weekend.


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#11 Rick

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Posted 16 April 2016 - 12:51 PM

Jim, your build tutorials are great for those that are new or just not as honed in building skills as you are. Just an example, I just got this e-mail from a new racer. Although there may not be many posts on your threads, there are a lot of hits. I think this e-mail will make you smile and just see how much you help out. TYVM!

 

Thanks!  I just wanted to share how important I see your kits and Jim's tutorials are to helping grow retro. I race with 3 young guys that each built one of your kits because of the accessibility of Jim's instruction getting ready for this coming retro weekend at our track.  They specifically chose Rgeo because they had the confidence to complete the project. Brass and piano wire are foreign and new to them. 
 
I shared with them the ease I had putting together my DS 7.5. And the great results. This is the way retro might have a future beyond all us 60's generation guys. 
 
Thanks for the thoughtful and well made products you offer. 
 
Best regards,

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#12 Dennis David

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Posted 16 April 2016 - 12:58 PM

Fantastic and well deserved!


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#13 Tim Neja

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Posted 16 April 2016 - 03:54 PM

Nobody documents his builds better than Jim!  He also gives us the "simple" way to do things and not complicated!! Heck--even I can copy his builds pretty well!  And his photo documentation and set up tips are the BEST too!! Love to see your work Jim--you've helped me and all others immensely!! Hope to see you here at the Zimmerman>   :)


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She's real fine, my 409!!!

#14 JimF

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Posted 16 April 2016 - 10:29 PM

Thanks to all for the extra kind words........it absolutely does put up a smile for me.

 

I tested again today on the little 90' Korkscrew at Motown raceway. I had made the changes that I mentioned in the prior post and this car leapfrogged to the top of the pack. The KS is a very different track than the ML and the conditions were a little loose for all these cars that were set up for higher bite. Still.....really good. As can be seen, this nose can be used about any which way you want and I even took a "blem" sample that I had and used it as an ingredient to startup an anglewinder.

 

Tomorrow is race day at Eddies and this will go to the track with the expectation of being one of two that I'll choose to race. Conditions there can be like a box-o-chocolates so anything can happen. I've done enough flat trackin' with this one now and hope to do the soldered vs. unsoldered test on a speedway soon. (I have a hunch.....but we'll see)


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#15 JimF

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Posted 22 April 2016 - 01:04 AM

Soooo...........this morning, I had finished up a couple of customer cars and plunked 'em in the tumbler. As I sat there, I started to think...........so.........geeze..........what am I gonnado while those things tumble? The answer was..........build another Shark for myself. So, I fired up the iron and got to work and a little over 3 hrs later, I had a new F-1 to play with. The Shark nose combined with Ricks F-1 pans make it so quick and easy that I can almost sit down without any forethought and put something together in almost no time.

 

This one is the classic "Samson" rail configuration, unsoldered. The Shark nose and the angled face bracket are .050. The pans and center weight are .062. This is one of those combos that always works. The complete car w/out center weight will go about 102 gr. and with the center weight in place, about 116 (ish).

 

I expect to do the soldered vs. unsoldered test on the original version this weekend. I'll test this at the same time although I doubt that I'll full solder the rails.

 

1-shark2%20001_zpsl0lkfy3v.jpg

 

1-shark2%20002_zpslxnrolzw.jpg


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#16 mgerbetz

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Posted 22 April 2016 - 11:31 AM

Jim, I just want you to know; Rick is right. I dont post much but I watch and read your every build and it helps me very much as I am starting to build. Many guys my age (45) and younger are paying attention to what you 60's guys are doing. It interests us greatly so we can continue to enjoy the hobby and pass it along.
Thanks!
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#17 JimF

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Posted 22 April 2016 - 02:19 PM

Michael, thank you very much. I do know that a lot of folks look/watch but don't comment, that all good. When I go to races or just visit tracks to test, guys are always asking...."hey, can I take a look at that (whatever) chassis that you just posted on?"

 

Still......it's nice to hear that it serves the general good.


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#18 Dennis David

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Posted 22 April 2016 - 03:29 PM

All good Karma Jim!

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#19 JimF

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Posted 22 April 2016 - 04:34 PM

Wellllll............just boxed up four customer cars for shipping and was feeling good about that so I was gonna go fishing.

 

But.........top pic is 1 hr. ago, bottom pic is right now.....

 

a763d5b1-2970-475f-a2ad-a5271d3ee71e_zps

 

504a343c-d79c-4a48-8ff6-7368acc60829_zps

 

So............I guess I gots to start something new.....don't even know what but I'll think of something.....................


Jim Fowler

#20 JimF

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Posted 27 April 2016 - 12:56 AM

Well, did the comparison Sunday and it was a split decision. The car was better on the speedway unsoldered and better on the flat track soldered. Interestingly there was almost no difference in times but in each case, there was a difference in how the car "felt" and drove. The test was done at Motown Raceway in Modesto Ca. and the two tracks used were their 155' tucked engleman/hillclimb and their 90' Korkscrew flat track.

 

What I did was took off all the weight and set the car up with a JK 8713 PP @ .795. I ran it on the speedway with a moderate Retro Hawk @ 9-28 & 112 gr. Then, changed out the RH for a Mini Brute @ 8-28 and left all the other running gear the same and tested it on the flat track. Then, I soldered it up and repeated the same tests. This took tuning with tires and weight out of the mix and just tested the car as built and totally stock.  

 

 

Unsoldered:

 

Speedway:

 

Really good, planted, easy to drive and fast (within one tenth of a good Can Am) If we ran these cars with this motor, I would leave it just like it was or maybe try to get a little weight out. Able to drive very hard. Best lap - 4.94,  avg = 4.96-5.0

 

Flat Track:

 

Good, fast, but felt jumpy and hard to be as consistent as I'd like. As my earlier tests suggested, this frame needed weight for the flat track. Best lap 4.54, avg = 4.59-4.67

 

Soldered:

 

Speedway:

 

Still very fast and consistent but now, it came off the corners a bit loose. Fastest time was actually marginally faster this way but I felt closer to the edge. It was a little harder to keep it in hand. best lap - 4.91 avg = 4.98 - 5.05

 

Flat Track:

 

Car was smoother and easier to drive this way. Ultimate lap was indentical but this way, I could run laps close to the max more easily. This way, the car felt more settled and didn't feel nearly as much in need of weight. Best -4.54, avg = 4.57-4.62

 

So...........

 

I honestly thought going in that it would be better soldered up on both tracks but I was wrong. This was a dream to drive on the speedway unsoldered and if we ran 'em this way, I'd leave it just the way it is. Tuning with weight can get the unsoldered version very good on flat tracks. Reflecting on the hybrid rail car and this one cause me to think that I'm going to rebuild this one with three rails of .047 brass flanked by one of .047 wire on each side but not soldered to the brass. OR......5 rails unsoldered, OR.....maybe the two inner ones soldered and the three outer ones not, OR................ :crazy:

 


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#21 Rick

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Posted 27 April 2016 - 11:44 AM

Great report , as always Jim! Now the watchers have some info to base their own build on. We don't have many flat tracks or technical tracks out in the East and even where they do have them, they don't get much action for retro racing.

 

Now we wait for the next chapter and what you do........................  


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#22 JimF

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Posted 27 April 2016 - 03:42 PM

Won't be a long wait, the existing nose and bracket are all decked out in a new rail configuration. In the tumbler now & will post a pic tonight.


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#23 JimF

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Posted 28 April 2016 - 02:21 AM

Here the latest. Same nosepiece, pans and bracket from the original but changed out the frame rails for a different configuration. This is 5 rails/side total. There are 2 X .047 wire surrounding 3 X .047 brass down the middle. The inner wire rail is inside the perimeter of the bracket and the rear tail drops right into the little notch in the bracket. At the nose, I cut a small additional notch for the front of that innermost rail. This rail setup is soldered at the ends only with a little bit under the cross bar in the middle, the rest is unsoldered.

 

This is intended (hoped) to combine some of the characteristics of the original 4 rail Shark with the Samson Rail version and maybe a bit of the hybrid rail version. However, this has a TON of flex so I'm unsure what it will do.

 

1-shark3%20003_zpsy3hnvaho.jpg


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#24 Tim Neja

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Posted 28 April 2016 - 10:39 AM

It will make a LOT of bite!! Looks good Jim!!  :)


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#25 John Streisguth

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Posted 28 April 2016 - 10:45 AM

Very interesting design.  I'm thinking maybe replacing one of the brass rails with a steel one and then soldering them all up might work nice.  If I may ask, where did you get the 047 brass?  

 

Looking forward to seeing how the testing goes on this one...


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#26 Cap Henry

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Posted 28 April 2016 - 11:14 AM

You can get .047 brass from K&S

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#27 JimF

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Posted 28 April 2016 - 11:39 AM

Very interesting design.  I'm thinking maybe replacing one of the brass rails with a steel one and then soldering them all up might work nice.  If I may ask, where did you get the 047 brass?  

 

Looking forward to seeing how the testing goes on this one...

 

Yeah......me too.......I'm thinkin' could go either way. I suspect that I may be working toward more of the rails soldered up as I go along with it.  BTW, as Cap mentioned, .047 brass is a stock size for K & S (labeled as 3/64").


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#28 Rick

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Posted 28 April 2016 - 12:14 PM

Are you installing center pan ? That would stiffen it up some? Maybe? I think its going to good....I have ideas too but don't want to change your thought process on this.


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#29 JimF

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Posted 28 April 2016 - 12:52 PM

Yep, center pan is made up and ready. The way I build 'em, I don't think the center pan stiffens it up much because the center crosspiece is free floating. If I soldered that up.....then it would be stiffer fershure.


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#30 JimF

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Posted 28 April 2016 - 12:59 PM

A little more on what I was thinkin' here. The Samson rail configuration was a fantastic innovation from Dennis. It always works and the combo of brass/bronze and steel unsoldered is great. However, it is pretty stiff. So......if the damping properties of the brass can be preserved while getting a more flexible/bitey frame......maybe all to the better.......Uhhhhh.....Maybe.


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#31 JimF

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Posted 05 May 2016 - 01:27 AM

First tests on the latest version shown in post #23.................

 

Test venue this day was Fast Track Hobbies in Rocklin Ca. I didn't have time to get to Motown in Modesto to recreate the first test and besides, the tracks at FTH offer their own sets of different challenges. Here are the two test tracks.........................

 

Speedway track is the "Purple Angel" this is about 165' lap length and is (I think) unique. Most of the turny section is interconnected so the car is more or less continually changing direction. The high bank is at the beginning of the main straight and direction of travel is right to left down the main straight. FTMP this drives like a very fast flat track and it is faster in lap times than both of the King tracks in our area.

 

c6a0e0bc-3a34-4f21-958a-fdb4e2b08d12_zps

 

Flat Track is the "Yellow Dragon" and as can be seen here, this is a technical challenge for driver and car. This track is about 135' in lap length.

 

aeb2715e-8e8b-4e07-9439-146bc7aacff8_zps

 

I started on the Purple Angel intending to test with a Retro Hawk. However, conditions were very dry and loose. I took a flexi car and glued the tires and ran it, glued and ran, glued and ran, glued and.......well you get the picture. Eventually, I got a lane to sort of work with the RH but it was still hard to tell what the car was doing so I put in a Mini Brute and the slower motor allowed the car to work pretty well. I took the three cars shown below and tested each car with the same motor, tires, gear set and body. We have raced F-1 with Mini Brutes on this track in the past and the best race time that I recall was about 5.38 sec. with good track conditions.

 

Test cars...............All cars tested in light configuration with center weights out as shown. Mini Brute motor, 9-28, JK 8703 PP tires, Parma Matra body.

 

1-new%20shark%20test%20001_zpszjhqqd93.j

 

Left = R-Geo "Toronto" concept car.

 

This is a multiple winner on speedway tracks. Best time here in past was 5.38. Weight 96 gr all up.

Best time = 5.48, best 5 lap sequence = 5.50 - 5.60. Good, considering conditions but a little twitchy and hard to hold on to.

 

Middle = Shark  "Hybrid Rail #1".

 

Proven flat track winner, never tested here before. Test weight 104 all up.

Best time = 5.53, best 5 lap sequence = 5.53 - 5.58. Not quite as fast as Toronto but better race car.

 

Right = New Shark (Hybrid Rail #2?)

 

Never tested anywhere. Test weight 100 all up.

Best time = 5.42, best 5 lap sequence 5.43 - 5.48. Easiest to drive of all three and fastest. Most stable of all cars in bad conditions.

Retested with center weight in - 112 gr all up. Best lap 5.48, best sequence 5.48 - 5.55. Slightly slower but still second best car.

 

----------------------------------------------------------------------------------------------

 

Flat track testing: If the conditions on the Angel were uhhhhh.......challenging, the conditions on the Dragon were great. This is a fairly new track to me and I've only raced on it once but I've worked on it pretty hard. My best race time with an F-1 in the past is 6.08 sec. I wanted to test three cars but time wasn't there so I only did two. Test cars as shown below with center weights in place. Same running gear as above except 9t pinion swapped out for an 8t.

 

1-new%20shark%20test%20002_zpsaxlgl5zh.j

 

Left: Shark Hybrid rail #1. Test weight 118 gr.

 

My most recent flat track winner. Very good on technical type tracks, never tested here before.

Best time 6.08, best 5 lap sequence 6.08 - 6.14. After testing this for 30 laps, I thought "Wow, I couldn't ask for better"

 

Right: Shark Hybrid rail #2. Test weight with center weight, no lead 113 gr.

 

Brand new car, first laps on a flat track.

Best time 6.04, best sequence 6.07 - 6.13. Easier to drive and more stable than Hybrid #1

 

Added lead on the center plate to get weight up to the 118 (same as Hybrid #1)

Best time 5.98, best 5 lap sequence 6.03-6.04

 

Obviously, this car needs more testing and tuning but for first go out of the gate....excellent. We have an F-1 race on a speedway track in a bit over a week. This car along with the Toronto will get set up in speedway trim for that race. I don't plan to full solder any of the rails until I've tested this car on other tracks

 

1-001_zps20lugh9v.jpg

 

 


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#32 Rick

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Posted 05 May 2016 - 10:13 PM

JIm, excellent report! The Hybrid#2 with the brass/wire combo is coming along nicely. IMO I was thinking the 2 brass rails soldered and wire rails open, but now I am second guessing that thought. Now you have more wondering if more rails will be better still? but I think you may be maxed out, maybe could squeeze one more .039 rail inside?..............


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#33 JimF

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Posted 05 May 2016 - 11:49 PM

There is no more room inboard for even an .039. My micro rail car has two inboard of .039 and the motor just fits. One of .039 and one of .047 won't make it. Of course, for more rails, one could go outboard and narrow the pans, but keeping the pans stock.....5 of .047 or 7 of .039 is max.

 

I'm interested in more rails as well. I immediately started thinking about more rails in a Can Am configuration. Possibly 7-8 rails/side of .047...........say a 3/4" bracket, then......two wire--three or four brass--two wire. All open for starts, then maybe solder the wire pairs leaving the brass open.......or???

 

As far as this one goes, there's more to do yet. With three middle rails of brass, one (center) could be replaced with wire. (wire-brass-wire-brass-wire) (or), the inboard wire rail could be soldered to the inner brass rail, (or) outboard wire to outer brass. Before I start messing with it though, I want to test it with a stronger motor and on a faster track.  


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#34 rodslot53

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Posted 06 May 2016 - 08:39 AM

Jim,

 

What is the rail build up of the Hybrid rail 2 chassis. In your opinion is this the better configuration for a flat track?

 

Rod.


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#35 JimF

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Posted 06 May 2016 - 11:48 AM

Rod:

 

If you mean what is the rail size, it is 5 X .047/side. Counting from the inside out, it is one of piano wire, three of brass, one more of wire. So far this rail configuration on this particular car, has proven very good on the one flat track tested on that particular day. However, I have several others that are excellent as well so saying it's better sort of depends upon the individual track on that day and also what you are comparing it to.


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