Making pattern for mould

Bitza · 02-11-2024, 05:19 PM

OK hi all, so winter is on its way and once salt gets spread I take the heap off the road and the winter projects begin. So in preparation for one of my projects I'm doing a bit of research. The project is to lop off the tail end of the bike, junk all the number plate carrier, undersea splash guard etc. Then to make a new carbon tail unit. So my question is what material to use to make the pattern from which to make the mould. I was going to model the pattern actually on the bike to ensure it's going to fit, I'm not aiming for a high gloss finish as the final item will be painted. Any suggestions?

Mr Gazza · 02-11-2024, 07:33 PM

The under seat tray is already a great material to take a mould off. It'll be polypropylene based which releases really well.
I've recently taken a mould off a number plate mount and it pops off a treat with just release wax.

Easy composites do a range of excellent mould making products. https://www.easycomposites.co.uk/mould-making

There's polypropylene sheet in there which is great for flat surfaces and single plane curves.
A hot glue gun is handy for sticking it together, especially if you're trying to extend a mould from something you want to keep afterwards, as it just peels off.

There's sheet wax, plasticine, soft wax for filleting and all sorts.

I favour using rigid foams, preferably the yellow stuff in the middle of Cellotex, with the ally foil peeled off. I sculpt this and then sheath it with a thin layer of 18gm woven glass cloth in resin. (epoxy or poly.) I've also used water based polyurethane varnish which works well if you're painting the object, but no good for a mould.
I'll then coat the sheathed foam with gel or epoxy and rub it back to a dead smooth finish for polishing and waxing for release. The woven rovings and resin sheathing are great to unify the surface if you've used several different porous materials like foam, MDF and ply for instance, or just stick to polypropylene, plasticine and wax which always release.

I think East Coast Plastics also sell the same products. https://www.ecfibreglasssupplies.co....Khsx8-BseLL2Mw

02-11-2024, 05:19 PM	#1
Bitza Silver Member Join Date: Jul 2006 Location: Poole Bike: M900ie Posts: 513	Making pattern for mould OK hi all, so winter is on its way and once salt gets spread I take the heap off the road and the winter projects begin. So in preparation for one of my projects I'm doing a bit of research. The project is to lop off the tail end of the bike, junk all the number plate carrier, undersea splash guard etc. Then to make a new carbon tail unit. So my question is what material to use to make the pattern from which to make the mould. I was going to model the pattern actually on the bike to ensure it's going to fit, I'm not aiming for a high gloss finish as the final item will be painted. Any suggestions? __________________ Bitza

02-11-2024, 07:33 PM	#2
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,981	The under seat tray is already a great material to take a mould off. It'll be polypropylene based which releases really well. I've recently taken a mould off a number plate mount and it pops off a treat with just release wax. Easy composites do a range of excellent mould making products. https://www.easycomposites.co.uk/mould-making There's polypropylene sheet in there which is great for flat surfaces and single plane curves. A hot glue gun is handy for sticking it together, especially if you're trying to extend a mould from something you want to keep afterwards, as it just peels off. There's sheet wax, plasticine, soft wax for filleting and all sorts. I favour using rigid foams, preferably the yellow stuff in the middle of Cellotex, with the ally foil peeled off. I sculpt this and then sheath it with a thin layer of 18gm woven glass cloth in resin. (epoxy or poly.) I've also used water based polyurethane varnish which works well if you're painting the object, but no good for a mould. I'll then coat the sheathed foam with gel or epoxy and rub it back to a dead smooth finish for polishing and waxing for release. The woven rovings and resin sheathing are great to unify the surface if you've used several different porous materials like foam, MDF and ply for instance, or just stick to polypropylene, plasticine and wax which always release. I think East Coast Plastics also sell the same products. https://www.ecfibreglasssupplies.co....Khsx8-BseLL2Mw __________________ Last edited by Mr Gazza; 02-11-2024 at 07:35 PM..