welding steel base or just getting aluminium extrusion

[EddyCurrent]

Similar here, I used a sabre saw to rough cut the parts out of a large piece, then used a pin router with templates and finally a belt sander to smooth the edges.
Slow but achievable.

[reefy86]

I know i must be doing your lots head in asking all the time and i apologise for this, are the aluminium extrusions straight enough for the gantry beam rails? I am using resin for the steal beams along the x asis and if i was also using steel for the y axis gantry then i would use resin there too but what about the aluminium extrusions?

[Desertboy]

Easiest solution for your plates is to get a fellow member to make them for you on their router (This is what I did). In which case it's probably cheaper to find someone to make your plates and have them sent directly to them than send them to you and then on again.

If you design your plates so they only need to be milled on one side you will make the job a lot easier.

If you do make them yourself then make them from ply/mdf/wood first before you attempt to make them from aluminium, it's a good idea to prototype in wood first anyway I didn't and in the end I had to do some post processing work because of it. My Z axis plate was catching the BK fittings limiting my travel a simple mistake due to using wrong carriage model for my Hiwin's and making last minute changes before cutting without noticing the Z.

[reefy86]

Don't want to be insulting to anyone regarding price but personally i think this is disgusting but then i am no expert on whats worth what when it comes to stuff like this. i have been quoted just under £2k just for 4 pieces and 2 of those pieces are only small plates for the rails

[Desertboy]

Don't want to be insulting to anyone regarding price but personally i think this is disgusting but then i am no expert on whats worth what when it comes to stuff like this. i have been quoted just under £2k just for 4 pieces and 2 of those pieces are only small plates for the rails

I think 1 or 2 guys on here might be able to beat that quote lol.

You're not the only person on here to get crazy quotes for simple jobs Alex was quoted crazy prices to.

It might be an area thing because I got much more reasonable quotes in Leicester ranging from £200 (If I supplied material) to £400.

[reefy86]

i'm going to order the plates and practice on a spare piece and see how i go first. would defiantly need the z axis plates being machined though as that has grooves cut out for the ballscrew mounts.

[cropwell]

Don't want to be insulting to anyone regarding price but personally i think this is disgusting but then i am no expert on whats worth what when it comes to stuff like this. i have been quoted just under £2k just for 4 pieces and 2 of those pieces are only small plates for the rails

I feel I have said this before, but Reefy, there may be two factors at work here :-
1. The company has enough on their order books to put them in a position where they can issue F**k Off quotes to one off machining.
2. They are cynically set up to cream off the desparate.

The price per unit if you were ordering 1000 off each would be a lot lot lower.

I would advise you to keep looking

Edit: Having looked at their website, I go for option 2.

[reefy86]

True but me personally would not be issuing F**k Off quotes when that person would potentially spread the work and bring me more custom regardless if i have mass companies ordering from me, I would just simply say to them i can but its months waiting list because obviously bigger orders are a priority in business :)

What F**ks me off the most though is they buy materials in bulk and have the machine to make these parts as if they are butter so more then likely it cost them hardly nothing for the material due to bulk buy and charge me almost £2k and thats not even half of the plates i need doing. on their behalf i bet its a good thing but for poor old me it bloody aint lol

[m_c]

They won't save that much in material by buying bulk.

People think that just because it's a flat bit plate, that it's easy to machine, but it's rarely the case. Taking your end plates for example, how would you hold them down?
On a router table, you could just screw the plate to the bed, or rely on a vacuum table, but I'd doubt they'd be using a router to machine them.
On a mill, you could clamp to the bed, but then you have to work around the clamps. You could use some form of low profile vice fixture, but you're still looking at two setups. Other option is to make a fixture plate, but that's additional cost and machine time.
Even your small plates, if you've specified tight tolerances around the full perimeter, instead of just using a bit suitably wide bar in a vice, milling both ends flat, maybe surfacing the top face, and drilling/tapping the holes, you now need to have two setups so all edges can be machined. Every time you have to do a setup, is time that has to be paid for by someone.

Plus you've specified a blasted finish, so that's more cost.

The quotes do seem high, but when you actually breakdown the time involved, they're probably not that high for a professional machine shop doing a one off job.

[mekanik]

Could be wrong but i think you will find the +/- .5mm will be on cut length,so all you have to do is group your sections together with all of one end flush lightly clamp them together, call the longest your master rail and measure the difference of the others (shims/vernier) if you recess your end plates these can be done to the same depth and on assembly put appropriate packing into the end plate(simples)