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Hopefully this will work. I hoping to have the Y axis 1500mm long and the x 850mm, this will help with the space i have available and will make it easy with placing the work material. i have 16mm rails,16mm screw on the x. 20mm screw and 25mm rails on the Y axis and i was thinking 16mm screw and 16mm rails on the x axis. This will sit on a steel box section frame. Have i got it right or wrong:confused:. Also going to use belts and pulleys, that's 45x 45 ali profile and 20mm ali plate as well
Hi Deanos,
Looks like a 'landscape' format machine with such a long Y axis gantry. 1500mm is quite a long span for a pair of 45mm profile sections. You could double the (torsional) stiffness if you go for 'portrait' format and have an 850mm gantry, although you do mention that you want to make it easy to load material.
If you want to continue with this style then here's Joe's cnc in case you haven't seen it, which is very popular:
http://www.joescnc.com/themachines-hybrid.php
Any thoughts on how you will attach the X axis drive system (pair of leadscrews I assume) to the gantry sides?
yes it will be a pair of leadscrews on the x axis, not sue on how to attach them yet.
Hi Dean,
There's pro's and cons to both portrait and landscape designs. Landscape is good for reasons like only having one long screw on Y axis rather than 2 long screws on X axis which is a problem with large format machines, space saving and easy loading are just a bonus IMO.
The down side is that you need to really beef up the gantry and your choice of 45mm profile fastened to a single plate will leave the machine very weak IMO.
Nothing wrong with the format great for light duty wood use but I would seriously look to beef up the gantry.
If you must use profile then why not use 45x90 sandwiched between 2 plates like the pics below.
The wider profile helps with ridgidity and mixed with the extra plate it would be very strong. Plus It has the advantage of protecting the screw with just a slot for the Y aixs ball nut mount bracket which is covered with simple brush draft excluders but still allowing ballnut bracket to slip by.Access is simple by unscrewing the rear plate.
The slot is easy cut into the plate by drilling hole either end then simply running circular saw up each side.
Keep up the good work. .:toot:
Jazz,
Is the plate with the slot still ali or wood, i'm confused with cutting with a circular saw. If i did beef the gantry up this way would i then be able to cut anything other than light wood, would it be able to mill aluminium if required
Dean,
From what I know of that design it is aluminum plate and you can cut it wit a circular saw blade for metal cutting. As far as cutting heavier materials, I don't know but have seen set ups like this used to cut metal, so depending on a few issues of torsion it should be possible. The question comes in how much twist or flex you will get while doing so and how that will limit you cutting depth.
Michael
Yes it's Ali plate and yes it cuts very easy using hand held circular saw used for cutting wood so long as it has a TCT tipped blade, preferably with a thin curf.Quote:
Originally Posted by deannos
There are purpose metal cutting blades as well but can be expensive and not required if just doing the odd bit of Ali cutting.
You could use a jigsaw but the hand held makes quick work of it and cuts a nice straight line.(Better if you use a guide or piece of wood to run against)
The hand held will cut 10mm plate in one pass just lower the blade in nice and slow and push at a slow feed. Make sure you use goggles and long length sleeves because the chips burn like crazy.
You can even cut Ali with hand held router if you take shallow depth pass's. Thats how my first machines gantry sides and Z axis where cut, I made a MDF template then used TC 6mm straight top bearing guided wood bit and cut around the templates in 0.25 pass's.!! . . . Scarey shit at first and took awhile to do but it worked ok.
With this setup you'll be ok for anywoods really so long as your not expecting to cut 20mm in one pass.!! and my comment about light wood use was aimed at your first design mostly.Quote:
Originally Posted by deannos
Regards cutting Aluminium then yes it will but you'll need to be sensible, don't expect it to take 2-3mm depth pass's or even 1-2mm. You'll be in 0.25-0.75mm Max area for acceptable results. That said this is still usable thou and if your realistic with DOC/FEED rates etc then it'll be ok.
My advice on sketchup, I see you are scaling the supported rail and the mounting blocks as one,
If you double click the entity, then you will be able to select them separately and then select the rail and press "S" then drag it to the length needed.
If you must use profile then why not use 45x90 sandwiched between 2 plates like the pics below.
The wider profile helps with ridgidity and mixed with the extra plate it would be very strong.
Jazz,
I don't mind whether i use profile or not is there something else i could use
Thanks for that tip, i thought it didn't look right but couldn't put my finger on itQuote:
Originally Posted by jcb121