Hi team
See pic, the first part I’d like to replicate in wet lay CF laminate. My problem - how to reproduce the clips that hold it onto the adjoining part:
The clips don’t have to be in carbon, I’m quite happy to bond in some plastic clips… but can’t find a source of any.
Any ideas?
Your only option is to either overlay that piece in carbon fiber, or make a mold off of the back side and make the tabs thick enough to carve into the proper shape with a dremel or file. You’ll also want a jig to join the two pieces together.
Ignore the clips on the back at first and make a mold for the front side then make your part. After that 3D print some new clips and bond them on. Printed(plastic) parts are not expensive these days. Heck even 3D printers are not expensive anymore.
http://cubify.com/cube/printers.aspx?hp_bn_printers
http://www.makerbot.com/
Right, so I’d build out the tabs with plasticine or similar and cast the tabs into the lay as monoliths, or perhaps use some 3 x 12 mm CF rigid section, then shape to purpose after casting.
Skinning seems a bit too much like the easy option and the 3D printing idea while neat is a bit pricey for what at this stage is hobbyist activity.
Cheers, and any other ideas still very much welcome
you could take a mold of a tab with some kind of silicone rubber/latex (i’m not sure how these products are called in english) and then duplicate the tabs by pouring into the mold only resin. i don’t know if it will be appropriate method due to the small size of the tabs but the cost will be low so you could try it.
I have tried what jimff1 said. I have a MUCH larger and complicated clip for Mini sideview mirror covers. I did a 2 part molding of the clips with silicone, and then injected epoxy with a syringe into one side of it. It kind of worked. It was a really complicated clip, and i ran out of silicone…but for that clip, you can make a 1 piece mold easily. As for the resin, you can used a toughened epoxy, or filled even. Something that can flex if it will be taken on and off. After that, just glue it on the part using a template to locate them.
Also, what you can do, is build up the silicone flange area, after the main mold is cured, to almost make a clip WITH a flange. THen you have something to bond to the part.
How about just bend up some thin gauge steel and bond it to the back of your part?
Make border around the back side and create mold through silicone resin. After cure you will have excellent mold that give you very good copy and very easy to take the copy from the mold.
This could work too. These clips are simple enough!
Yeah, I go for simple when I can. Earlier today I posted in another thread that sometimes we use high tech solutions for low tech problems. I see it a lot. We like a material or process so much we lose the forest for the trees. Trying to mold a net shape like this from a pourable resin system is probably not going to work long term even if you could fill well. The original part is thermoplastic with particular properties that make it work well. I think using a thermoset in this manner is less likely to succeed for any length of time.
I suppose an alternate, if you really want a molded part, would be to lay up a piece of flat stock and a 90° laminate that will create an “L” shaped piece. Bond the flat to the 90 where the bottom of the flat is at the appropriate height to form the bottom of the clip. Grind the resulting assembly to form the agular face of the clip. Bond to the part.
Cheers for all your helpful comments guys. I’ve found a different solution, which is to disregard the original tabs altogether and form a new tab as a flange on one end of the part. I can slot this into the adjoining part (a rear bumper) by cutting a small, discrete slot. The part should then be held securely in place and I’ll use some sticky foam pads to make sure, underneath.
First lay up didn’t work well but I think my mold was unnecessarily complicated, so try again…