New Avant Slot 2024 Chassis

[big dennis]

I have been following the progress of some of the 2024 releases from Avant Slot, and recently bought one of the new Kremer Porsches.
Prior to my purchase I was enthusiastic about some of the new features, including :                                                                                                                                                                        
1. 'Softer' motor rated at 21,000 RPM compared to the 23K, 25K and 35K motors that have been supplied in other Avant Slot cars that I have purchased. (The higher RPM motors have often proved to be over-powered for the tracks that I usually race on).
2. A revised chassis with wider side-pans that allow the body to sit on top of the chassis, which minimises the side-to-side 'body-rocking' motion that occurs on the older chassis because of the 2-point body-mounting  set-up.
3. A coil-spring rear suspension that might improve handling on certain track surfaces.
4. Installation of a 'hard' green motor pod with a separate motor-carrier that enables the motor position to be adjusted to assist with setting up a proper gear mesh.                                  
When discussing 'point 4' on a recent edition of the Worldwide Slot Car Chat it was pointed out by two of the other Zoom participants that there was a potential problem with a pod design that included a separate motor-carrier. Unlike the one-piece standard pod there is not a solid connection between the rear of the motor-mount and the axle bearing holder.        
And when putting the car on the track for the first time the problem became obvious. There was severe 'axle tramp' immediately when power was applied, and it was near impossible to drive the car slowly enough to prevent the violent shuddering. It would seem that the chassis is flexing between the main pod and the motor-carrier causing the motor pinion and the spur gear to move 'out of mesh'.
To try and fix this problem I have glued the  motor-carrier and main pod together, making sure that there is a solid connection between the rear of the motor mount and the gear-side axle bearing holder. I will be unable check whether the problem is fixed until the next time I visit my local track.

Curiously there wasn't any mention of such a problem in a recent YouTube review of another of the Avant Slot 2024 cars that uses the same type of chassis.                                            

Den

[charlesx]

Hi Big Dennis.

That sounds like a fairly serious problem. Hard to believe a company like AVANT would have such an issue. Hope your fix works. Can you perhaps fit a Slot-it or NSR motor mount. That might be better still. AVANT are not generally raced in NZ so no other suggestions. Not sure about Thunderslot mount but another possibility. MIght depend on your class rules of course.

Regards Charles Le Breton (charlesx)

Edited August 18 by charlesx

[big dennis]

Yes Charles, it is a bit strange that the 'axle tramp' problem wasn't detected in testing. It's similar to the legendary 'Ninco Hop'.

The pod mounting points on Avant Slot chassis are not compatible with those other brands that you mentioned. However, over the years I have accumulated quite a collection of Avant chassis parts and if need be I will just install a (solid) one-piece pod from my supply of spares.

The LMP/GT1  class at my local track has fairly liberal rules with only the NSR Mosler 'banned' from racing so far. The most popular car is the Revoslot Toyota  GTOne.

I have had some podium success with Avant Slot inline-chassis cars (Porsche Spyder and  Kremer Porsche).

While the Avant Slot cars may not be renowned as a leading performance brand they do turn out some very attractive LMP cars, and that is what inspires me to race them.

Den

[charlesx]

Fair enough Big Dennis.

I am a great improviser so your fix should work. Could not get an NSR SW chassis recently so turned AW one into SW. A very easy fix. Also made Slot-it FC130 motor mount into a slim-line motor mount but think Slot-it may make one now anyway. I know Mr.Slotcar do. All I did was cut standard one in half, remove fillet and glue back together. I wanted to fit in Tasman Cup car but later found this was not allowed (brass only) so it has never raced in anger.

Seem to recall Avant Slot have produced some really good cars in past. As an aside seeing as you mentioned Mosler, we have an open GT class/ now completely open but all our members race NSR Moslers. I refuse to follow suit (in other classes as well)) and have had fun at times racing other cars against them. My current model is an NSR Corvette but I am also trialling my NSR Classic Porsche with an up-graded motor. It is fun trying which is what slot car racing is about.

Slotting since 1960 and for the rest of my life on this planet. Regards Charles Le Breton (charlesx)

[Chrisguyw]

18 hours ago, charlesx said:

 

. Also made Slot-it FC130 motor mount into a slim-line motor mount but think Slot-it may make one now anyway. I know Mr.Slotcar do.

CG Slotcars also make a sidewinder (050) motor mount,......(same screw pattern as Slot-it)

Scaleauto have an inline 050 mount.

Cheers

Chris Walker

[charlesx]

Thanks Chrisguyw.

Not aware of CG or my brain is not working. Used Mr. Slotcar AW 050 in Lotus 30 in USA. Pretty basic car but went ok.

Good to hear from you Chris. Always enjoy your builds. Regards Charles Le Breton (charlesx)

 

[Vinno]

Olifer do a slimline motor mount with adjustable axle bush posts that take the Slot.it spherical bushes. They used to be a little loose but the last batch I bought are nice and tight. You can alter axle height to your hearts content depending on wheel tyre diameter and use offset pinion gears for a good mesh. 

[charlesx]

Thanks Vinno.

I am not doing much scratch building these days but currently in progress of extending my track.

Regards Charles Le Breton (charlesx)

[big dennis]

Kremer Porsche adjustable chassis update :

Tried using Superglue to solidify the connection between the motor-carrier and the rear axle uprights, and it quickly broke away due to the torque of the motor.

Have now used Araldite epoxy  to stiffen the chassis and will have to wait until my next race-meet to see if this latest fix works.

Of possible interest to other Avant Slot owners is that the new wide 'outer chassis' will be available as spares, namely part numbers 25069a and 25069b. These should suit any Avant car with an 85mm wheelbase, including Kremer Porsche, Pescarolo LMP and Lotus Elise GT1. Note that the detachable front 'pan' may differ between various body styles.

If you wish to obtain the chassis spares you may have to arrange a special order with your preferred retailer.

Den.

[Chrisguyw]

On 8/27/2024 at 11:45 AM, big dennis said:

Kremer Porsche adjustable chassis update :

Tried using Superglue to solidify the connection between the motor-carrier and the rear axle uprights, and it quickly broke away due to the torque of the motor.

Have now used Araldite epoxy  to stiffen the chassis and will have to wait until my next race-meet to see if this latest fix works.

 

Den.

Hello Dennis, as you have discovered, Superglue is far from the best adhesive to use in your situation, as it has very little shear strength, and even low strength motors will "crack" the join. While epoxy is certainly better, you could get a Sloting Plus axle tube/bushing assembly, and once installed make a "V" shaped brace out of piano wire (.055) and epoxy this to both the axle tube, and, the rear of the motor case.

The axle tube will eliminate the independent flexing of the rear axle uprights (which causes axle binding/bushing wear) and the brace between the tube and the motor will eliminate the flex in this area which results in,...wheel hop and mesh issues.

The Sloting Plus "Combi" axle tubes come in 3 various lengths,.......you will need to measure from the center of each rear axle upright to determine the length you need.

Cheers

Chris Walker

Here is a pic. of the Sloting Plus axle tube installed in an NSR chassis,.....I do not have a handy pic of a chassis with the piano wire "V" installed, but a narrow "U" or "v" epoxied to both the axle tube and rear motor case is the ticket.

 

 

[kalbfellp]

I even know where Dennis can get some Slotting Plus axle tubes close to home!

[big dennis]

I'll be in touch with you soon Phil.

Thanks for the advice Chris.

[big dennis]

Unfortunately due to severe weather in my local area I haven't yet been able to re-test my Avant Slot Kremer Porsche after making changes to the set-up, namely replacing the adjustable motor-pod with a fixed pod.

Firstly, the owner of my local track was without power for several days, and has since been cleaning fallen trees in the aftermath of that severe weather.

However, I have now watched two (2) video reviews of the Kremer Porsche  and in my opinion both demonstrate the problem that I have mentioned in earlier posts.

In the first video there is noticeable 'wheel hop' as the car leaves the start line at the beginning of the track test. That problem may have occurred on other occasions during the track test but the 'ambient noise' of running on a plastic track makes it difficult to verify.

In the second video the reviewer demonstrates the spring suspension by pushing down on the bar that holds the suspension components. The spur gear can be seen moving away from the pinion due to the flexing between the adjustable motor-carrier and the main part of the motor-pod. This flexing is likely to cause 'wheel hop'.

Den

[Chrisguyw]

On 9/18/2024 at 10:07 AM, big dennis said:

 

 The spur gear can be seen moving away from the pinion due to the flexing between the adjustable motor-carrier and the main part of the motor-pod. This flexing is likely to cause 'wheel hop'.

Den

More than "Likely" Den,........the flexing IS causing the wheel hop!!.............additionally, the flexing causes mesh issues, and, the independent flexing of the rear uprights, results in alignment issues of the bushings/axle binding.

Cheers

Chris Walker