TOPIC:

I'm working on my Williams FW11, in the manual is says to glue the two large flat parts of the chassis together with "synthetic rubber cement". In the past I've used Evostick "Impact" & that works fine, but I'm not sure that's what Tamiya had in mind... that seems to be what the previous owner of the FW11 had used, and it was difficult to separate the halves & clean it up.

I'm thinking the "rubber solution" in cycle tube puncture repair kits might be more like it - I think Tamiya must be suggesting creating a flexible & firm but impermanent bond.

Anyone have any experience of using this on GRP parts, or any other suggestions?

I don't have any experience with GPR parts, but when I need a flexible semi permanent bond on my foamies or in leather work I use UHU POR or EPP Quick grip. Both a rubber type contact cement.

Dasbeermeister wrote:

I don't have any experience with GPR parts, but when I need a flexible semi permanent bond on my foamies or in leather work I use UHU POR or EPP Quick grip. Both a rubber type contact cement.

Thanks

I decided to try the glue in my puncture repair kit (I thought I might as well, it's been years since I acutally owned a bicycle) - it's all clamped up & curing as I type

Only a guess, but "Rubber solution" (For fixing bike tyres) is an impact adhesive -the type of glue where you apply thinly to both surfaces, let it dry out, then bring both surfaces together & apply pressure to bond - perhaps that's what Tamiya are trying to say/point you at?
As far as I know, most adhesives will join GRP, as long as it's properly cured (Poor curing will cause styrene-based bleeding, which will go for paint, glue etc). For a hard/strong bond, I'd suggest roughing up the GRP & using 2-pack resin of some kind (Isopon P40 resin, slow-cure epoxy etc), but I suspect you want a flexible bond, in which case EvoStick Impact would be best for strength & still have some flex. With a bit of degreasing, you might find silicone would also do it if the GRP surface is shiny enough

The bicycle "rubber solution" worked ok - I just put a fat bead near the edge & a couple more to fill the gap down the middle & squidged the two bits together straight away - I must have judged it fairly well as I could see through the "white" (or "natural"?) GRP that I got full coverage, with very little coming out the side.


The big question is what Tamiya actually intended the joint to be - rock solid, flexible, or just enough to stop fretting, who knows? I suspect what i've achieved is the latter, as peeling off what had escaped once it had set showed the bond was pretty weak. The chassis & subchassis are held together by 5 screws anyway, so I think most of the strength/rigidity would come from that - and the strength of the "glue" bond would be trivial in relation.

Step 4 says to remove the screws after the cement has cured though.
I think they intended to make a flexible joint there, probably for the driving characteristics.
Giving too much oversteer otherwise...

I googled the question a bit but nobody seems to have a straight answer.
Especially tank builders are wondering...
I did see some alternative pop up a few times but I'd have to take a look again what that was.

The manual does say to take 3 of the 5 out, but all of the 3 holes get clamped up by other bits - the front by the nose/front suspension assembly, the rear two by the battery cage.

Yeah, you're right. I was trying to add that bit of into simultaneously with your previous post.
That would actually be an improvement of the software, when it would detect that and ask if you'd like to alter your post...
But that put aside.

Trying to visualise if there's any flex left when the upperdeck is mounted...
Haven't really decided yet.

Going through the manual, I now think it's actually the other way around. Can't imagine it's not functional.
Guess it's meant to stiffen up the main chassis and "separate" it from the flex in the rear end.
Solved with a T-bar on younger cars...