[andre acker]

I decided to modify a Scalex Brabham bt44 after looking at the beautiful examples showed here.
It seems that the 1/1 car had a 2413 mm wheelbase, which means 75.40 mm in our 1/32 money.
According to Tamiya designs, the car was 1992 mm wide at rear (from the external side of the left wheel to the external side of the right wheel).
That means 62.25 mm in 1/32.

I will build a narrow chassis with piano wire and use a mild motor.

Now, the wheels and tires.
I think that 20 mm (diam.) x 14.5 mm (wide) tires on 11 mm wheels at the rear will be ok.
At the front, 16 mm (diam.) x 8.5 mm (wide) tires on 11 mm wheels.
As I normally run on a "wood track", I can make the sponge tires.

But for a "plastic track" or for these events on wood tracks, where sponge tires are not allowed, which wheels and tires do I have to use to have
good results ?

Are there rubber or silicone (if allowed) tires with similar sizes ?
NSR ? Slot-it ? Ortmann ? Any other maker ?
Are there 11 mm (diam) wheels where to use such tires ?

I have no idea about what to use.

Many thanks for your help !

André Acker.

 

[Mick Kerr]

Hi Andre,
13inch wheels are actually about 11.5mm over the rims in 1/32 scale.

You best options for rear wheels and tyres are;
NSR F1 wheels (these are about 12mm dia) fitted with their F1 tyres. These tyres are a copy of Ninco's F1 tyres and 'only' about 12.5mm wide.
Slot.It F1 wheels (these are also 12mm dia) fitted with NSR F1 tyres. (Slot.It don't make F1 size tyres to fit these wheels).
Obviously the Ninco F1 tyres will also fit these wheels.
Ortmann also make Ninco F1 size tyres and you might find them better than NSR on plastic track.

Penelope Pitlane make an F1 wheel which is a copy of the '70s Scalextric wheels (as fitted to your Brabham) and there are Ortmann replica tyres for these cars.

For the fronts there are two choices:
Slot.It wheels and tyres as fitted to their Ferrari 312PB and Alfa.
Penelope Pitlane make a replica Scalextric F1 front wheel (again as fitted to your Brabham) and Ortmann have the correct Scalextric replica tyres for them.

NSR and Slot.It wheels should be easy enough to find almost anywhere.
I can't see the Penelope Pitlane F1 wheels on their site but you can find them on the Pendle site under Spares/Scratch Build Spares/Penelope Pitlane.

Hope that helps.
Cheers.
Mick.

 

[Fastjet57]

For what it is worth.

I have numerous plans for 70's F1 cars, BT44 included. I plan a more ''off the shelf'' approach with my starting point a Fly March 761 (just raided ebay for a few). Rear wheels and track about right already (slightly wide (65mm+) but could narrow axle a bit if required). Front suspension a bit wobbly and slightly narrow for a BT44. So what I did last time (Lotus 72E) was to replace front end with Scalex M23 wheels/axle and narrowed to required front track dimension.

As I just run on a Scalex Sport track, with a bit of gluing, truing and oiling, I get performance enough for me with basic Fly/ Scalex wheels/tyres.

Original Scalex BT44 looks very short wheelbase (agree with your 2.413 - from Ultimatecar page.com) - so some chopping to fit to the Fly chassis probably required, but not too difficult stuff. I googled Brabham BT44/44b and got a good Tamiya side and plan view (guess you did the same).

Good luck.

Not started my conversion yet - on a list of 12 to do.

Phil.

 

[andre acker]

Thank you very much, Mick !

I will try to find these wheels and tires.
It seems that the best idea is to combine Ortmann tires with Penelope Pitlane wheels.

The Scalextric McLaren M23 front tires can be bought (with the rear tires) from Pendle but I
wonder if they will fit the Penelope Pitlane front wheels.

Will the Ortmann tires be competitive on wood tracks ?

Best regards !

André Acker.

 

[ferraif40]

Hi Andre

Slot.it do an F1 tyre in the F22 compound, which will also fit on the Penelope Pitlane 70s replica rear wheels that Mick talks about.

Regards
Jon

 

[andre acker]

Hi Phil,

Thanks for the info.
The "French" Scalex version of the Brabham bt44 (# C122) seems to have the correct wheelbase,
but I am still waiting for confirmation on this.
If so, I will try to get one.

The Tamiya plans are very good !

And do not forget to consult Indycals ( http://www.indycals.net/index.html ) for the decals.
I consulted them about 1/32 scale decals for the bt44, lets see.

Best regards.

André Acker.

 

[andre acker]

Thanks Jon !

Which model or # are these tires ?

André Acker.

 

[ferraif40]

Hi Andre,

SIPT29-20x12 F22 F1 Tyres

Regards
Jon

 

[conti_rowland]

All my builds of this period receive Ostorero wheels and tyres which they originally made for their Lotus 79 model.
They are nice soft rubber and grip real well on the Ninco track we use here.
They have an OD of about 21,5mm which I believe is closer than 20mm to scale.
Be aware that their front wheels have a 1,5mm hole rather than 2.38 or whatever....
Check the Brabham or Surtees links below to see how they look.

Cheers

Andi

 

[andre acker]

Thank you, Jon and Andi, for the info !

André Acker.

 

[TheCuckoo]

Looking forward to seeing this build

 

[andre acker]

Calm down !
I am still negotiating the bt44 and buying parts, decals etc.
Then I have to make the chassis.
But it will arrive !

André Acker.

 

[Mick Kerr]

QUOTE Slot.it do an F1 tyre in the F22 compound, which will also fit on the Penelope Pitlane 70s replica rear wheels that Mick talks about.
Sorry I had not noticed the introduction of these tyres.
However, I'm sure they are made to fit Slot.It F1 wheels.
The central rib on the PP wheels is very narrow and will not correctly locate these tyres.
I'm sure you can come up with a way of gluing them on centrally though.

QUOTE Will the Ortmann tires be competitive on wood tracks ?
Depends on the track and surface.
On some tracks they're very good on others NSR will be much better.
I find it's worthwhile having both available.
Cheers.
Mick.

 

[ferraif40]

Hi Mick,

The Lotus 72 I raced at the Wolves Half Tonners and 3ltr's last year ran on PP wheels, with the Slot.it F22 F1 tyres on, and I didnt have a problem with locating them on the wheels. Probably the only bit on the car that worked all weekend!

Regards
Jon

 

[andre acker]

I've sent mails to Pendle and RSSlotracing but no replies so far ...

RS has the Ortmann tires ; Pendle has the Scalextric original tires for the McLaren M23 and the PP wheels.

I've also contacted BWA about wheels for these Ortmann rear tires and maybe for the Scalex fronts.

Maybe the solution is to get the Slot-it rear wheels (SiPA20ALS) and tires (the above mentioned SiPT29) as I can
not find the number of the NSR products.

And use the Scalex fronts with some improvised wheels ...

André Acker.

 

[Mick Kerr]

Hi Andre,
NSR Formula 1 Ultragrip tyres Part No 5221 available from Pendle.
These are grooved tyres but by the time you've trued them to the correct diameter the grooves will have gone.

Ortmann rear tyres to fit PP wheels are 36a ribbed or 36c slicks.
Ortmann front tyres to fit PP wheels are 37c ribbed or 37 slicks.
All from the RS Slotracing lists.
These tyres will match the original tyres on the Brabham BT44.

The modern McLaren M23 and Ferrari 312t front tyres do fit the PP front wheels and will be 15.6mm diameter when fitted.

Cheers.
Mick.

 

[andre acker]

Hi Mick The Encyclopaedia !

Many, many thanks for you help !

Now I am ready for shopping.

By, the way, have you seen or heard about these ones ?

http://www.ebay.com/itm/150660063933?ssPag...48#ht_500wt_922

Take care !

André Acker.

 

[Ian H]

I've had some for another car.

Not too impressed really.

They run very round and concentric but don't grind them, just clean them with tape of rubbing alcohol.

I prefer good old fashioned rubber!

 

[andre acker]

Hi Ian,

Are you talking about the Canadian tires ?

André Acker.

 

[Phil Kalbfell]

Here is my version built on a Fly Chassis from a US resin.