DCC Supplies Digi-Hat Convert Graham-Farish chassis safely to DCC in minutes!
Q&A Q. So, the spring is a fuse?
A. No. The spring is made from 0.32mm (28awg) Beryllium copper wire, which has a capacity of 1.4 amps. Or, put another way, most 'N' gauge decoders provide 0.8 -1 amps. The current draw of an average Farish motor is 0.3 - 0.4 Amps. Q. OK then, will heat draw the temper of the spring?
A. No. Beryllium copper is tempered at 460° C for an hour. With a loading of 1 amp the temperature increase of the spring is negligible. (see below) Q. Does the spring get hot?
A. No. At 1amp heat generation is 0.003 W/second (per 1000m of wire!), heat dissipation is 105 W/m*k, again, well within tolerances! Q. Will the DiGi-Hat melt?
A. No. The material has a melting point of 140°C. Q. Is it true the DiGi-Hat absorbs water, expands, and splits?
A. No! The material used (a copolymer of Polyoxymethylene) is designed for use as a bushing material, and is specified at less than 0.5% absorption at 100% immersion. (measured by ISO 62-Sat/23C) - and after all, we're not discussing submarines here! Q. What makes this the best solution?
A. DiGi-Hat is a designed and engineered solution. It uses high quality materials chosen specifically for the task, and engineered by a specialist company with over 35 years of experience, under compliance with BS EN ISO 9001 : 2000
Now Supplied with Kynar®
heat shrink tube. Tougher than standard tubing, and half the thickness!
Designed by DCC Supplies.
The DiGi-Hat We've worked on hundreds of Graham Farish locomotives for our customers, and, depending on the chassis, each loco can take between 45 minutes and an hour to convert. This is purely down to the difficulty in insulating the motor components from the chassis.
Typical chassis are the old 'Poole' built diesel's, and most steam locos (No special kits are required for modern diesel chassis) and the challenge to a DCC conversion is the fact that the motor brush is built into the live chassis. A brass 'top hat' provides the housing for the carbon brush, and in turn is held in place by a sprung brass clip, providing electrical connectivity to the brush, from the chassis.
There have been a number of attempts in the past to solve this problem, different methods for steam and diesel chassis, but all involving a major strip down, machining and the application of easily damaged or degradable insulation materials, or application of paint as an insulator.
Ultimately, with these kits, success is dependent on the skill of the fitter, and the amount of care, and time that is able to be invested as once drilled, a chassis can easily be damaged beyond repair.
SO After considerable thought and research, we designed our own modification, which is now available for sale - the DiGi-Hat is a carefully thought out solution, fully researched, from the careful, informed choice of materials, to precision engineering tolerances in production. Our manufacturer is an industry leader in insulation and plastics engineering, and have been fully involved in the project from the start. Using the spring as a conductor is quite within its current carrying capacity (see sidebar), also worth noting is that some decoder manufactures use 28AWG wire for motor and accessory connections on some decoders rated over 1amp.
Improved: We now use only Kynar® sleeving, which being a mere 0.5mm thick, avoids the problem found on certain steam locomotives where standard tubing fouls the wheels, and therefore removes the need for filing. Amazingly this material has more abrasion resistance than standard heat-shrink, so is more resistant to tearing during assembly.
No major disassembly, no risk, 100% retrofittable, no drilling, no painting, and easy conversion back to DC. (keep the value of your loco!) Full pictorial instructions provided
The DiGi-Hat is a direct replacement for the existing brass guide, and with the provided heat-shrink sleeve enables you to make an extremely professional job of a DCC conversion, better still, it takes 5, rather than 45 minutes to convert a loco, and there is no drilling, additional materials, or irreversible modifications required!
By simply removing the 'old' brass brush guide, inserting the insulating DiGi-Hat and adding the heat shrink sleeve to the clip, all that is then needed, is a wire soldered to the exposed section of the clip, and fed through to the decoder. We can provide a modified clip for those who wish to save even more time!
The DIGI-HAT fits all Poole style chassis, which are most of the range steam and diesel locomotives (newer Diesels do not need this kit), if the motor brush is held in place by a brass clip, then this kit is required.
Upgrade of many Graham-Farish Diesels will be eased by the use of a pair of DiGi-Hat, as the top guide also requires insulating from the conductive brass strip, The DiGi-Hat has been designed to work here as well, in this case, no additional insulation of the clip is required, although a wire must be soldered to the top, and connected to the decoder.
The Digi-Hat is available as an individual component, with Kynar® heat shrink sleeve included to insulate the clip, or in a kit, with a modified clip (with attached wire, either orange or grey to NMRA Standard)
Of course, all our Farish conversions now use this system, and whomever converts it, you can be assured that you've fitted a quality product from DCC Supplies.
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