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V8
The V8 is installed
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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22nd December 2010
Dragsters and racers

Dragster
The finished dragster - it is a bit too heavy for the pull-back motor as it will only make a sedate 'taxi' along the drag strip!

With little activity on the Meccano front and a period of really cold weather here in London, it has been good building time. If you have been following the picture progress at the bottom of the home page you will have seen some progress pictures of a dragster I have been building.

The new Xtreme Dragster set got us thinking about building more realistic looking dragsters and we are not alone. Deep in the depths of Meccanopeople's model rooms the faint sound of tinkering can be heard. E-mails have been exchanged and the design and construction has begun. No-nuts has been banned (no it's not an insult, it is the selling point of the Xtreme kits - no nuts). The new pull-back motor is being extricated from its chassis and transplanted into a custom frame, or two.

I started building the first model for a proposed club challenge but it got a bit out of hand and far too heavy for the pull-back motor hidden under the V8. Instead I decided to build it for looks using only 100% Meccano parts. The only things that don't work for me are the back wheels. I am going to use something non-Meccano, me thinks...
...but here it is in it's current form - 100% Meccano parts.

Rod
The hot rod with driver - I think he might need a roll cage...

While messing around I thought it would be fun to have a go at building a dragster hot rod. This one has a slightly smaller V6 engine and again is built entirely from Meccano parts. Too heavy to be a contender in any speed race but it is a bit of fun. Now I must start thinking about building one for speed…

Quad bike racers

The other project that has been giving me some trouble is our version of the pre-war race game that incorporated governors to disengage the drive if the crank is wound too fast. Initial attempts have been disappointing and after a lit of adjusting here and fiddling there I decided that a clean start would be the best course of action. With spanner in hand the whole front end was demolished. In order for the mechanism to work efficiently it must be free moving and set in a very rigid frame. No amount of tweaking will rectify the models shortcomings if these two conditions do not exist.

Raceway
The first attempt worked well enough to prove the principle but needed a rethink as far as the drive was concerned

mockup

First the governors were redesigned to minimise the drag on the rod. In the original design a three-hole coupling (P/N 63) was secured into one end of a socket coupling (P/N 171) and a ½inch wide, ¾inh diameter pinion (P/N 25a) is secured at the other. Meccano tolerances being what they are it is almost impossible to get this combination to slide freely on a standard rod. Drive detailTry as I might, with lots of different combinations, it would not run freely when the grub screws in the socket coupling were tightened. If they were left a little slack I could get it to work but prolonged use would result in the assembly shaking itself loose and the component parts becoming detached.

Drive
After building a mock-up the new arrangement for the governor and drive was proven. The main difference is the drive shafts are inline. As can be seen from the pictures the final version has the step-up speed drive over the input shaft in order to make a neater job. the three drives are colour coded for clarity and to add a bit more visual interest

The new design has been prototyped and modified slightly in order to keep the whole mechanism in line. Angle girders have been bolted across the large flanged plate (P/N 236) to prevent it flexing in the middle. The addition of these parts made a huge difference to the smooth running of the mechanism. I was surprised how much those large plates will distort if they are not well supported.

New drive

The model is well on its way to completion again and I am hoping to take it to the SELMEC meeting in London on the 15th January 2011 and TIMS in Telford on the 12th February 2011. I will add articles about the building the racer and the dragster models to the website over the next few weeks.

Ralph.

 

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V6
A V6 engine for the Hot-Rod
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
gov
The redesigned Governor without the coupling fitted into the top of the socket coupling
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ews