Member postings for HomeUse

Following on from Neil’s post I can confirm that for one off castings a core of 3D printed PLA will “burn out” satisfactory for casting purposes, but if the 3D print is ABS then the “burn out” leaves a residue which creates faults in the casting - I have not cast in Brass, using mainly Aluminium and occasionally Silver

Hi Neil - What is the finished scale you are looked for.

If you wish to wash out (Water Soluble Plastics) from the mould then it will need the mould to be made from a material that is stable in water and also in high temperatures - Normally for us model engineers the moulds would be smaller and made from a material such as “Investment Plaster” (A gypsum with additives) or a build up of ceramic slurries (China clay with additives) nether of which are really suitable for washing out (The china clay would be ok after firing but by then the wax would be burnt out)

Myself I use PLA filament in the printer and invest in “Plaster” then burn out in the furnace at the same tine as melting the metal (Usually Aluminium but also Brass/Bronze)

Water soluble filament is used in printing support structures and then dissolved out of the main strucure

Used to use one very similar in design but built in the early/mid 40’s to turn skittle balls out of “lignum vitae” on a peddle driven lathe (lathe later fitted with electric motor)

Yes 5/32 x 40TPI (ME) Thread

Have been using TurboCad MacOS Version 7 and currently 8 for a few years now (Originally used Windows but new machine dictated the change)

Once you get used to it, it is a very powerful drawing system both for Architecture and Engineering Design - My hardest part was trying to forget the operating commands used in the windows versions as they are totally different.

Now I have got the hang of it, I could say that it could be slightly quicker to operate than the windows versions, but there is not a lot to chose between the two.

The principal of variable speed pullies is described in the attached link - years ago there was articles on how to build one - can’t remember the magazine - link http://www.berges.de/download/e/11_03_23_BERG_DA_RD%20b_E6.pdf

At least you know the quality of the one you built, and not hoping that the eBay cheepy will live up a “fit for purpose” usage

There is a company on model engineers Facebook pages that specialise in lost wax casting ( 3D Printed wax ) - his email contact is [email protected] - the company is Crow Fittings Engineering Services

If you have not used the stripper yet - make sure you soak the stripped boiler in warm soapy water after using the “mors” and then washing well in clean water

Have used this controller for 12 & 24v motors Brushed and brushless - Am using 4 to control the motors in 5” gauge loco. Also on lathe feed screw.

DCM DC MOTOR CONTROLLER MODULE - Farnell

You will need to type into search engine as does not work as link

Thanks Dean - “I had vision of massive calculations to adjust the weight of each piston “ - But I really knew that it was a stupid question.

Hope the final lapping goes well

Regards Mike

This may be a stupid question but is there any reason for some of the pistons having a domed recess in the bottom of the bore and other do not (8 do 4 do not)

Keep up the good work

Seem to get good results with cutting/tapping aluminium by using WD40 as a lubricant

Trouble is the “Departments have not got joined up office communications” 👉 Diane you’ve been sacked 😢

I am using 4no 12V 100W (ex kids scooters) on a 5inch gauge Scratch built (American looking loco) - One fitted to each axle and driven by toothed belt geared to give top speed of 10MPH - Each motor is protected by a 10amp fuse and speed control is by a scratch built system. The power source is my caravan leisure battery - its on the heavy side but that helps to keep it on the track .

The loco pulls well and has ample power - although the next one will have 6 axles with 6no 12V 130W motors.

Hi Dean - Glad to see the update - keep them coming as it is a great project

The “one to be obeyed” is now complaining that the updated version iOS has changed the operation of the tablet for the apps she uses - Cant win can we

“O SO RIGHT” Neil

Updated iOS on wife’s pad - Works ok now - She’s not to happy about me using it when on holiday