167 replies to this topic

[Alan Draht]

The front end of the lower cross-bace incorporates a bracket and hinge pin for the chassis' guide flag drop arm.

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[Alan Draht]

Upper braces have body-mount holes pre-drilled.  Hole locations match the Maldonado dragster's body-mount attachment points.

 

The same is true for main rail cross-brace attachment locations.  With a couple of exceptions, they match Maldonado's side rail attachment points.

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[Alan Draht]

The frame's front end required special attention.

 

The nose plate incorporates a system for attaching the dropped axle mechanically instead of soldering in order to avoid exposing magnesium frame components to soldering flux and acid fumes.

 

The brass dropped axle pictured here is one that typically comes packaged with the K&B Model-Rama wheels.  It is not suitable for this project.

 

Imagine sawing a correctly sized/ shaped dropped axle in half.

 

Each half, left and right, will be inserted through the main rail's 1/8" hole into the nose assembly's 5/32" brass tube at the correct rake angle and through-bolted to the magnesium nose piece, locking it into position.

 

Assembly, disassembly, re-assembly of the entire frame is easy using mechanical fasteners.

 

Typically, fasteners will consist of 00-90 brass hex head bolts, washers, and sometimes, nuts.  If a threaded hole is stripped, it can be re-drilled and tapped fro the next size up, 0-80.

 

Contrast that approach to frame construction with Manuel Maldonado's assembly method 55 years ago which consisted of epoxying everything together with 1/16" aluminum tubes and straight pins.  

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[Alan Draht]

Maldonado's magwinder has a number of what I'll call "ornamental" lightening holes carved out of the rear ends of the main rails.  The weight savings is negligible but stylistically they look cool.

 

I will create some but not all of these openings -- for the triangular armature-carriers and the main rails -- once I have the gear guard attachment points established.

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[Alan Draht]

Since my last post, work progressed on the front end and the dropped axle assembly.

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[Alan Draht]

At this point in time, my Maldonado - styled dragster is mostly complete.

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[Alan Draht]

Details of the front end, dropped axle and outriggers.

 

(Ignore the modern guide flag.  A vintage Cor-Ben guide will be used in the car's final assembly).

 

 

 

 

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[Alan Draht]

All holes were drilled and tapped for 00-90 size brass hex head bolts, washers, and sometimes, nuts.

 

If, over time, a 00-90 hole's threads strip out, the hole can be drilled and tapped for the next size up, 0-80.

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[Alan Draht]

The top rear cross brace hinges up to allow access to and clearance for the top brush assembly.

 

It's also handy for installing/ removing the driver figure.

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[SpeedyNH]

that's truly artistic. 

[Alan Draht]

A true magwinder, this dragster, like Maldondo's, does away entirely with the stock Ram motor's endplates.

 

It uses the the magnesium frame's left side rail to carry the brush assemblies.  The armature is carried by a pair of triangular-shaped magnesium plates bolted to the side rails.

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[SpeedyNH]

do you have a place to test it? 

[Alan Draht]

Thanks, Steve!  It's true.  For me, this is art.

[Alan Draht]

Yes, I can test it at Mike Swiss's Chicagoland Raceway.

[SpeedyNH]

excellent.  and i'll bet he'll be really glad to see all that fine work. 

[Alan Draht]

I've got two dragsters to test at Mike's drag strip.

 

I did not test my Husting replica because I needed to re-magnetize the motor's original Alnico magnet.

 

I did use the magnet zapper at Mike's track to zap the motor's magnet, but was not fully prepared to run the car that day.

 

For one thing I only had/ have one decent set of Graupners mounted on Russkit dragster wheels to use on that car.  The other tire sets wobble badly and are unusable.

 

That's one of the things I have yet to do, for both dragsters:  soak the badly-mounted tires off of their rims and do over again, this time with more care.

[Alan Draht]

To finish the Maldonado dragster, fabricating and painting the body is at the top of the list.

 

 

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[Alan Draht]

Other items on the "to do" list include grinding the motor's field laminations to reduce weight and optimize magnetic force...

 

**  Fabricate and install a gear guard

**  Drill an eight-hole pattern in the 69-tooth spur gear to reduce weight

**  Replace the existing guide with a vintage Cor-Ben guide flag

**  Power wiring between the guide flag and the motor

**  Pour/ install lead nose weight (1 oz. +/-)

**  Replace existing drop arm's spring with a heavier-gauge spring

**  Mount and true new tires

**  Polish magnesium side rails and apply clear coat

[Alan Draht]

This dragster's weight, minus the body, gear guard and power wiring, is  6.7 oz.

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[Alan Draht]

Also, after weeks of waiting, I acquired a new magnet zapper -- a "self-contained magnetizer" as the industry terms it -- so now I am able to re-magnetize any Alnico magnet to full strength.

 

It's also good for re-magnetizing "C" and "D" can motor magnets, using correctly-sized steel slugs in place of armatures.

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[Alan Draht]

One of the things I forgot to include in the list of tasks remaining to complete this project is fabricating and installing a gear guard.

 

Fortunately, I machined two gear guards in tandem when I built the Gene Husting replica R&C dragster.  This saves me the time and effort involved with fabricating these parts from scratch.

 

Two 0.100" thick magnesium plates were bolted and machined together to create the slender "ring" surrounding the spur gear.  Then, the plates were unbolted, so that the front end of the gear guards could be machined separately from one another, since the Husting and Maldonado magwinders are configured differently.

 

 

 

 

 

 

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[don.siegel]

Beautiful work Alan, very inspiring. 

 

Where did you find the rezapper and how much was it? Not that I'm going to import one to France, but wondering about ballpark prices. 

 

Do you, or anybody else, know how that weight compares to other magwinder dragsters? 

 

Don 

[Phloidboy1]

Any testing time trial results of the Husting & Manuel dragsters ?

[MSwiss]

No, not yet.

He or I would of posted, if he had.

Alan seems to do things in spurts.

[Alan Draht]

No, not yet.

He or I would of posted, if he had.

Alan seems to do things in spurts.

 

Actually, I've been working almost continuously on slot car stuff this past year, but I did take a break from my Maldonado dragster project in the Fall of 2020 to work on a couple of other projects as well.

 

For example, I rebuilt a vintage K&B kit dragster using a lightened 6 volt Pittman DC-84/85 motor.  I made some improvements to the chassis, mainly replacing the stock stamp aluminum drop arm with an arm that functions better.  I also added a new aluminum body with fold-down tabs a la Gene Husting's 1966 R&C dragster for attachment to the aluminum frame rails.  This stiffens the frame considerably.  I also installed a 1 oz nose weight cast with low-temp lead alloy.

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