PDA

View Full Version : RFQ: anyone wanna quote me to cut some ally?! and....



robmurf
31-08-2010, 09:58 PM
hi folks :wave:

i'm a total cnc/cad/cam newb but need to get some small machined parts from aluminium for a product idea i have.

i'm looking at maybe learning about setting up my own mill/router to make em at home but at this stage i wanted to find a small friendly machine shop or perhaps a home hobbyist who might be interested in quoting a price to make my first batch.

in first instance i'd really appreciate advice on how to present the details of the parts to a machine shop to make it as easy as possible for them to quote me.

i think the pieces awill be a pretty simple 2d cut from approx 6mm ally sheet/plate. i've designed the parts in sketchup and have exported the drawing as a DXF file. see links to pics below. but i read somewhere that DXF is not ideal?

http://picasaweb.google.com/118229989803820225871/CadCamStuff#5511670682948550354

http://picasaweb.google.com/118229989803820225871/CadCamStuff#5511670678214665986

i've read a LOT about how to get from sketchup to CAM and to G-code but i've only succeeded in totally confusing myself. i guess i'll have to work it out at some point if i want to design AND make my own parts.

anyway sorry if post is a bit long but ANY advice/quotes would be really great!

OH, i've used emachineshop and think the site/software is really cool but the price they're quoting for the part seems very high and i have some concerns about quality of finish going that route too.

Many thanks!!! :smile:

Rob

Robin Hewitt
01-09-2010, 11:48 AM
Tips for getting a quote...

You have a rectangular pocket with rectangular bulges inside it.

The gap between bulge and pocket sets the maximum tool size.

Suggest you make the gap as big as you can and then radius the pocket corners to fit that tool.

Should have a tolerance. I suggest your best tolerance for a quote off a hobby site is... "How close could you cut it without making it expensive?".

Aluminium bar comes in 4 metre lengths so if you only want one you may want to supply the material. Add an allowance so there is somthing to hold on to.

Robin

robmurf
01-09-2010, 01:16 PM
Robin

MANY thanks for the reply, really helpful, I appreciate it.

Those bulges don't need to be rectangle they could be any shape, e.g. I guess round following the shape of the holes? I just need something to give the holes a wall thickness, you know what I mean? I drew them as rectangles because I sort of assumed it's be simpler to machine, probably completely wrong!

I'm also re-doing the drawing to make the pocket corners a radius rather than square which i assumed would also get the drawing thrown back?

Thanks for advice on tolerances too. I don't really know yet what tolerance I need! I know that's the WRONG thing to say but I am going to work it out somehow before submitting drawings/files for quote...

I'm working on re-doing the drawings now will post asap, if you get a chance to look again, that'd be really cool!

Thanks again :o)