Sci fi backpack PEP WIP

[Harry Pepper]

Hi Guys
First ever pep project just need some advice, I have built the below very hard mount board and I was wondering when it comes to the resin/matting stage is it ok to tape the sides together with masking tape? will the resin still bond to that? also how much bondo would you need to cover this? I can only seem to find small amounts on amazon.co.uk, not sure which brand is any good either anyone have any recommendations of products used? any help much appreciated
Cheers guys!

 

[Blaxmyth]

I'm pretty sure that polyester resin will dissolve the adhesive on tape. At least, it did when I tried it some time ago...

Not sure about epoxy resin, though.

 

[Harry Pepper]

Yeah I thought it might exposy is a good way to go i think
Cheers!

 

[Harry Pepper]

Also how about hot glue? would the fibreglass resin melt that?

 

[Contec]

If you use superglue for the edges it will hold. Tape will dissolve Bondo is a brand name and there are other automotive body filler that works the same, It just have become synonym for all body fillers. So use what ever you can find at your local car tool shop.

 

[Harry Pepper]

Thanks Contec! how much coverage do you get I want a thinnish layer that will have a little strutural strength but they all look very small from what I've seen?

 

[Contec]

Thanks Contec! how much coverage do you get I want a thinnish layer that will have a little strutural strength but they all look very small from what I've seen?

What you want to get is a can, and not from a tube as that will not last very long (tubes are for smaller holes in the car body). Body filler is suppose to be used sparingly. It's a bitch to sand if you apply too much at once, Better to apply a little and then sand, and repeat until you have built up the layer you want.

 

[Harry Pepper]

Legend. Thanks

 

[Harry Pepper]

Hi Guys
Another query, regarding fibre glassing. I have just gotten a fibre glass kit and I was wondering if it will bond to almost anything? I am using a very strong card with an almost gloss finish, should I sand it before putting the resin on?, or will it just harden around what you apply it too? Also there is expoy resin from where I stuck the side together will that effect it?
Thanks!

 

[Blaxmyth]

I've used high-gloss card for pepping and found that the resin will stick to it, but it can be a bit patchy. A light sand might help the resin to soak into the card before it hardens. I don't think the epoxy will be too much of a problem.

One thing that surprised me - polyester resin does not have a strong bond to polyester resin that is well cured. I thought it would grip really well, but I found it will come apart under stress or flexing. Just add second or third coats onto the resin when it has hardened, but not cured completely.

 

[Harry Pepper]

Thanks Blax! thats really helpful, interesting about the resin too, I think your right about sanding it slightly. I need to start thinking about bonbo too but I can only seem to find this body filler called P.38 and I have no idea wheather thats what I need?
Thanks again!

 

[Blaxmyth]

I'm in New Zealand and we don't have P38 or Bondo - but anything that is used for repairing cars will do. It's all pretty much the same - a mix of polyester resin thickened with talcum powder.

We also have the same product sold cheaper for the building trade. Here it is called Builder's Bog. Check out a local panel beater (car body repair, or whatever you call it where you are) and they will tell you the best/cheapest place to get it from.

 

[Uridium]

Harry are you in the UK?

Isopon P38, is the stuff you want. I use it on my pep work.

As someone said earlier in the thread, make sure you put it on thinly, it takes a lot of work to sand it down. That is a mistake I learnt from on my first project.

My only other suggestion would be an electric 'mouse sander'..... trust me, your arms will thank you for buying one.

 

[Blaxmyth]

My only other suggestion would be an electric 'mouse sander'..... trust me, your arms will thank you for buying one.

Brilliant suggestion! I always thought they were a gimmick until I tried one. Use a really coarse paper - I usually use 40 grit - for rough shaping of cured bog. Wait till it is properly cured, otherwise it clogs the paper. Let the sander do the work - in other words, do not press hard on the surface, just hold the sander lightly against the bog so the abrasive can cut easily.

 

[Harry Pepper]

Hey Uridium I am indeed in the UK I think Ive got the right stuff, will definitely get a sander too as that seems to be the cry of the masses! Ill be posting some updated pics asap, thanks for all the help guys!

 

[Harry Pepper]

Got some isopon p.38 it even sees easy sand although from what I have heard there bending the truth slightly lol

 

[Blaxmyth]

Got some isopon p.38 it even sees easy sand although from what I have heard there bending the truth slightly lol

Not really - it's just that until the full cure happens, some of the solvent remains in the mixture and causes the sandpaper to clog. I have a curing cupboard with a 75 watt light bulb inside, and most bondo will cure OK overnight to the stage where it sands easily.

 

[Harry Pepper]

Hey I've used this stuff before called apoxie sculpt which is awesome however its also quite expensive for the amount you get does anyone know of anything thats a similar effect for a little cheaper?
Thanks Harry