56 replies to this topic

[Pablo]

It scares me just looking at it 

[dc-65x]

I've got the motor in the chassis:

 

 

I had to modify the Weldun spur gear by counterboring a .050" deep pocket:

 

 

That allowed the track to be narrowed .100" to better fit the body:

 

 

The lead wires are Cox Superflex, the guide is a Cox quick change, axles are Koford, ball bearings are from Boca Bearings and the Weldun gearing is 19T/62T which mesh smooth as silk:

 

 

 

Time for a track test:

 

[Isaac S.]

Looks good!

[don.siegel]

Beautiful work Rick - as usual. 

 

Nice detail on the gear; maybe you could start producing replacement gears for the Russkit Carrera sidewinder chassis... Kind of the same principle, eh? 

 

Very interested to see how this runs. The couple I've used have had decent speed and a very smooth torque curve... they probably need a rezap after 50 odd years too... Have you ever tried one of these with Arco magnets? Wondering if the arm would match those... 

 

Don 

[dc-65x]

Thanks Isaac.    
 
This works for a spur gear attached to a set screw wheel hub Don. I first saw master builder Pete Hagenbuch do it in a 1960's build article:
 

I wanted to run a full size 16D Mabuchi motor, no shortened cans or axle clearance ground into the magnet. That meant a spur gear at least 7/8" in diameter. The rear tires would have to be slightly larger diameter at 1" instead of 15/16" the R&C rules allowed.
 
The next problem was rear track width. How do you fit a full size Mabuchi, 2 Russkit extra wide rear wheels and a Weldun set screw spur gear under a 2.83" wide Carrera 6 body . You don't without some fiddling.
 
So maybe Mike took the wheel and gear to the Russkit tool room and asked their Duffy (tool and die master machinist) to hook him up. Get rid of the Weldun set screw hub and attach the gear directly to the wheel. This is same concept used in the Russkit Carrera series cars molded wheel-gear. Here's my "what if" wheel-gear:
 

 
Here it is all screwed together. It worked out pretty slick:
 

 
Time for the chassis...

The problem with using Champion magnets with the shim Don, is the RAM armature is bigger in diameter than the Mabuchi. I also tried using these RonCo magnets and shims which are about 20% stronger than the Mabuchi's:

 

 

With the shims the air gap is too small and the arm won't fit. Without the shim, fitting them in the can is a problem. Of course I could monkey around and epoxy them in the can but I'm trying the Mabuchi magnets first. They have worked well in the 2 other Ram-Boochie's I've built so we'll see.  

[don.siegel]

Thanks for the explanations Rick - clear as usual! 

 

I do know about Pete's old gear trick because I have a couple cars using that very system! They could be called anglewinders, since they have about a 2° angle, but because the gear is screwed into the wheel, we know the builder was trying to make it narrower, and so it's a real sidewinder (I've run the MkIV at Bordo, where anglewinders are not allowed...). 

 

Let me see if I can find a couple pix. I've posted a bottom shot below, but don't think you can see the gear too well... 

Don 

 

 

Hmm, it wasn't actually on this car, but one of its sisters, a McLaren... 

 

[Slot Car Rod]

Great build Rick.  Rick and I had the same discussion regarding Champion magnets.  I have one car with a 36D Ram-Buchi set-up.  The car is geared 3 to 1 and could use more brakes. 

Here is a car that has a 16D shortened motor from Rick.

 

[dc-65x]

TRACK TEST REPORT

 

This car is very fast.  

 

It's geared 3.26:1 and it's still accelerating like gangbusters before I have to clutch for the bank. I'm glad I have that big banked turn at the end of my straight. I can use almost the entire straight for speed and not waste 1/3 of it for a braking zone on my little track. 

 

Speaking of braking, this car could use more brakes too Rodney. My track is kind of a "momentum track" so it's not that big a problem. 

 

OK, so it's geared a bit to low (numerically) for my track and it could use more brakes. But you know what, it's also the fastest car on urethane tires I've tested so far by almost 1/2 second per lap.     WOWZERS!  

 

But I'm getting ahead of myself. My first test session was with the 3 different Cox repop urethanes from Canada, France and Ortmann's I pictured earlier. They all were close to or just beat my previous lap record. But they all seemed a bit squirrely and the lap time increased very quickly from when freshly cleaned.

 

Below is a fastest lap with the tires tested. The Ortmann's were on top and about a tenth better than the previous lap record but look at the last timed lap. It's almost a second slower than with them freshly cleaned.

 

 

The car just asked for more bite. I love the way the repop Cox tires look but I had to try a bigger tire. Luckily I built the car as narrow as I could and I could just barely fit these big dogs.

 

 

Those are Ortmann Monogram Slicks compared to the narrower (but more realistic looking) Ortmann Cox Firestones:

 

 

Here's my lap time with the Ortmann Monogram slicks. And check out how little they times dropped off from freshly cleaned:

 

 

I really like the way the car drives with these tires and that's what I'm keeping on this car:

 

 

 

Here's a link to the other urethane tire equipped cars I've tested so far:

 

Track test lap times

[Pablo]

     I have advice - if it's fun to drive and stays in the slot, it's done 

[don.siegel]

Excellent news Rick, and very interesting seeing all the times. 

 

FWIW, I've never had good luck with the Ortmann Cox repros, whereas the Monogram repros were my go-to tire for many years (I now use mostly Paul Gage tires for various reasons). Never could figure out how two tires with theoretically the same formulation could be different... 

 

Don 

[dc-65x]

I agree Pablo.     I'm moving on to the body.  

 

Thanks Don. Paul Gage tires used to by my go to for urethanes. But he's decided not to ship to the the US anymore. Says he's had it with people bitching about the shipping time. I know Rodney and I never bitched, we bought lots of his tires and I promoted his tires and eBay store here on Slotblog. But he's still refused to sell to us. So even though I have a pretty good inventory of his tires I'm not using them as long as I can get Ortmanns and the French tires. 

[dc-65x]

This is the Hamill sports racer I'm using as inspiration for my version:

 

 

Not only is purple but check out those white 5-spoke mag wheels  

 

Since I've settled on the wheels and tires it's time for some cool 5-spoke mag wheel inserts. I'm using wheels from an AMT 289 Cobra model kit shown on the left below. It was easily held in my hobby lathe 3/16" collet shown in the back. In the center and on the right is the wheel turned down to 1/2":

 

 

Here's the work in progress:

 

 

All that's left is to part off the little hub on the wheel that the lathe collet was holding on to. The "pot chuck" bored out to 1/2" works great to hold on to the insert to work on the back side of it:

 

 

[dc-65x]

Here's the Lancer #149 Hamill SR3 body I'm using:

 

 

The body is a little yellowed but it shouldn't be a problem with the color I'm using:

 

 

I've seen pictures of Hamill's in both right and left hand drive and even some that look almost centered. I decided to use this Lancer Porsche Carrera 6 interior because it fit the body really well so my car is left hand drive:

 

 

Here are all the goodies for the body. A set of Detail Master velocity stacks, Russkit Chaparral exhaust pipes, a roll bar of 1/16" aluminum rod and the wheel inserts:

 

 

Time to paint if the weather will let me..........

[chrisguyw]

Outstanding as usual Rick !!...........I am sure you already know this, but, just in case..........if you place a "yellowed" Butyrate body on the sunniest widow sill in your house for a couple of days, a lot of the "yellow" will be bleached out.

 

Cheers

Chris Walker

[MattD]

If you have been getting tir4s from Bruno (slotcartyres) in France, he has passed away and that source is gone.   I got a lot of his tires and was always happy with them.

[dc-65x]

Matt, SlotCarTyres is back and running again. I just bought from them and the tires, service and shipping time was excellent.

 

Here's a few lines from their website:

 

Dear customers and slotting friends,
It is with great pleasure that I announce the reopening of SLOTCARSTYRES.

 

Here's a link:

 

Welcome to our vintage and modern slotcar tire shop.

 

 

[don.siegel]

Yes, it's been taken over by  William Ingelbrecht, who's an old slotter and has built a number of tracks, hundreds of chassis, etc. He's now bringing production back up to speed. 

 

Don 

[dc-65x]

I got the body painted.......sort of.  

 

I love the color. It has a nice amount of metallic and it even "flops" a bit as the light changes. I used discontinued Testors Model Master Plum Crazy rattle can:

  

 

The "sort of" is due to the fact that the paint is SO translucent and needs to be backed up. But I have small areas along sharp corners where there is no coverage.      I can't back it up like this.

 

I kept adding coat after coat trying to get complete coverage. I shook up the spray can like crazy and heated it in hot water to get it to spray finer. I let the paint skin over between coats. I tried different spraying distances and angles but I still have some small areas without coverage.  

 

I'd rather be soldering.........

 

OK, my plan is to let this slow drying enamel dry for at least a week or two and mask off the body again. I found a bottle of Plum Crazy brush paint at a hobby shop in Montana and it's on the way. I'll break out the air brush and try to use its fine control to fill in the offending areas.

 

While I wait I'll be working on my "99-cent Ferrari" thread.......

 

 

[Martin]

Sounds like you have this under control.

Before I saw you were going to brake out the air brush, I was wondering if backing the purple up with black might be a good option? Just a thought.

Great looking color BTW.

[dc-65x]

I thought about black too Martin. I'm hoping to get full coverage with the air brush and go from there......

[dc-65x]

On this particular paint job, with this particular spray can I had trouble getting even coverage and worse, any coverage at all in the bodies sharp corners.  

 

What a mess:  

 

 

I used so much paint trying to get coverage the masking starting lifting off the windscreen:  

 

 

I finally got the air brush and compressor setup on a cart so I can roll it out my garage "man door" and spray into my trash can spray booth. With the air brush my paint coverage was much better and more even. The paint still didn't like the bodies sharp corners but it was good enough to let me back up the purple with gold rattle can and be done with it.

 

This is shining light through the body from underneath. With the body on the chassis it looks great......

 

 

 

I've got the dreaded brush painting done and it's ready for final assembly and decals:

 

 

 

[Pablo]

   

[dc-65x]

My Ram-Boochie powered Hamill SR3 is all finished. I thought I'd show this quickie picture I took of the car in the sun to try and better show the beautiful Plum Crazy color. It really is a PURPLE color with lots of metallic. 

 

 

The rest of my picture taken in artificial light look blue to me.   

 

 

 

 

Lots of "pipes and stacks".....

 

 

......and big bore power:

 

 

 

[Bill from NH]

The sunlight really enhances the vibrancy of the purple. Another great build Rick! 

[don.siegel]

That looks great Rick - and fast! 

 

Don