Hi guys!

I started making mold for mudguard and I  have now couple of questions.

1. can i use hammerite appliance paint on my plug? Becouse I did it and now it looks little bit like orange skin. Can i sand it to get smoother finnish?
2. can I apply Polarshine T10 before waxing on plug and later on mold?

Thanks

Hi Andris,

I think you might really struggle to get a decent release off Hammerite paint. If it's a spray-can then there will be solvent in the paint that will be leaching out of the paint for a long time to come. Often we hear of customers having lots of problems when trying to get a release off a pattern coated with rattle-can paint and I suspect that Hammerite will be at least as bad.

Regarding the finish, that's another problem with Hammerite - it does actually have that textured 'eggshell' finish which is not going to help when it comes to a decent finish on your mould.

If you want to persevere then the only think I can suggest would be to cure the paint as fully as you possibly can (i.e. leave it somewhere very warm for as long as possible). When the paint has properly hardened then you might be able to flat it (with a medim grit abrasive) and then possibly even polish that up to a decent finish but I really don't know and I would imagine that the Hammerite will make life pretty difficult. If it sands and polishes then there is a chance it will release from OK but I would test a small area first or at least prepare yourself for the likelyhood of the mould sticking to the pattern.

I hope this helps.

Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

Hi, again

Idea about Hammerite was very bad, because after two days I tried to clean it with acetone and its simply washed off.
So I sanded surface with 60 grit paper and paint it over with polyester resin. Sand it up to 1200 grit, but when i put on masking tape to make flanges, polyester cout came off with tape.

Its old Honda CF70 mudguard, so lot of dents and scratches, thats mean I need for filler to get nice shape.
Can somebody recomend whitch filler to use and what to paint over it to get nice surface?

And can I use fiberglass laminate sheets for flanges instread of sign board or something like that.

Thanks
Andris

p.s sorry about my bad english.

Hi,

Mmm, it doesn't seem like anything wants to bond to the plastic - it could be a plastic that's really difficult to bond to like ABS or polypropylene - in which case you have a couple of options. Option one is that you key the surface really heavily with a coarse abrasive paper and then use epoxy resin to coat the part - epoxy will bond better than paint or polyester resin - this might give you a good enough bond to do your surface prep and then pull the mould. Option two, if you really can't bond to the plastic surface is to use this to your advantage and pull a quick mould straight off the plastic surface. You can then use the quick mould to make a fibreglass mudguard (with all the surface defects still there) but then repair the fibreglass mudguard and polish that up to the final finish before taking your proper, final mould off that fibreglass mudguard.

And can I use fiberglass laminate sheets for flanges instread of sign board or something like that.

Yes, that would be fine.

I hope this helps.

Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

Or if the part does not have to be perfect, I would doctor it up with some body filler, make a mold from that and just do a bit of prep workin to the mold itself. then make you new part with CF, and I did see  they have a flexible resin just for this.

It skips a step but is not as clean of a result "but close" Make sure your tooling gel is thick enough to sand into if needed.



If Brute Force Isn''''t working your not using enough...

remember also that dents and scratches will come out as raised bits on the mould, so you could use a nice and thick layer of tooling gel to give you enough thickness to sand smooth.

Any sharp dents or creases you can probably fill with filleting wax on the part to make the job easier. Filleting wax when warm will also fill in deeper scratches.  Means less material to remove on the mould.

If the part is a mess, then do as matt suggests as ultimately you can do more with a new plug to get it perfect.