Sturdy and Fast all Steel CNC , my first build

**Boyan Silyavski** · 02-09-2013

Waiting for the square rails and ballscrews purchace, made me play again with the design. Decided to stuff all the electronics inside the body. Due to various reasons like avoiding
10 Neutric connectors sticking out at the back, cables, enclosure and so on. mainly because i live at the seaside so connections always give me trouble and i have to glue my connections with hot glue.

Decided also to make the structure from 60x60 4mm at the important places and 3mm at the no so important. But what ever i did i couldn't figure placing diagonals so i finished with rigid square design and 100kg structure. more or less 18meters of steel. I think i overbuild it a bit.

Another decision was to make the bed deep enough so there is no need to change spindle position. Instead a wood bed would be fitted so the spindle works at normal position and only when necessary to remove the wood bed, not move the bed of the machine or anything.

Hope that structure is strong enough, cause tomorrow will order the steel.

If somebody sees something wrong, please tell me until is time, he he.

**Boyan Silyavski** · 20-09-2013

Everything ordered including the steel for the structure. Still have not ordered the laser cut parts. Untill i have the rails and ball screws at hand.

And here comes the first major problem. The place where i found the 140x80 profile for the gantry refuses to sell me 1m even they have promised me before.

. Now i have to buy 6m , or change the design.

At the other place where i would buy the rest of the steel, i found some pieces of 100x100x4 box profile. And generally they will sell me everything cheaper and help me in their machine shop. So now i am contemplating soldering 2 pieces of 100x100 and making the gantry 100x200mm. That would change the design of the gantry widening 2cm, one at each side and making it higher by 6 cm.

What is your opinion about this change? The ball screws will be further 2 cm from the z plate. And the upper bearing slides and rail will go 6 cm higher.

**Boyan Silyavski** · 25-09-2013

No body says nothing, may be the thread is not so interesting as it seems to me or i am doing it right

Soon will make it more interesting with pictures of the process. Now everything is ordered including the steel profile. Will have to pick it tomorrow and solder it this weekend.

At the end i used only 100x100x3mm steel box for everything. The 4mm seemed very heavy and overkill for the 0.8kw spindle .
I still have doubts for the threads on the rails so most possibly will solder additional plates for the threads of the rails. Anyways they will be covered by epoxy.

Here is the final design , its lighter and stronger than the 60x60x4 and also another point is that less cutting and soldering is needed.

400x1000 x Z 170/up to 200/ working area, gantry ~35-40kg with everything mounted, profile structure and gantry with plates = ~ 100kg

**WandrinAndy** · 25-09-2013

Originally Posted by silyavski

No body says nothing, may be the thread is not so interesting as it seems to me or i am doing it right

Hi silyavski,
There may be another explanation and that is maybe something wrong with the forum...... I have been lurking recently and don't recall your post #25? Although individual posts may sometimes get lost in a rush of posts!
Cheers,
Andy

**JAZZCNC** · 25-09-2013

Originally Posted by silyavski

No body says nothing, may be the thread is not so interesting as it seems to me or i am doing it right :hysterical

I didn't see these post's either.!

Anyway it's looking good. The 3mm wall thickness will be fine for the rails holes but don't drill them until you have epoxy on the rails. If you do it before then you'll create your self more work.

**HoGo** · 25-09-2013

This provoked my first post here...
I'm in the middle of my own build (quite similar to yours) and I'm using 100x100x10 so I'd throw in a few words... Don't overlook the edge radius of your SHS. I got unpleasantly surprised when I was supplied with 100x100 SHS that has 35mm (or perhaps even more) diameter at edges... I was counting with 25mm diameter I found in tables of SHS somewhere but the supplied steel was cold rolled with much larger edge radius. My rails will be right at the edge of square so I added thick plate on top of SHS to support the rails. You may not have this problem with 3mm wall but I'd check at the supplier and verify the design with that in mind.
Good luck!
Adrian

**JAZZCNC** · 25-09-2013

Originally Posted by HoGo

Don't overlook the edge radius of your SHS. I got unpleasantly surprised when I was supplied with 100x100 SHS that has 35mm (or perhaps even more) diameter at edges... I was counting with 25mm diameter I found in tables of SHS somewhere but the supplied steel was cold rolled with much larger edge radius.

That 35mm is very large Diameter and your correct it should be more like 25mm, I have some 200x100x10 here and that is only 22mm Dia. I would have took it back.!!

The Dia on 100 x 100 x 3 will be roughly 8mm, I've got some 150 x 150 x 5 here and the Dia is 12-14mm.

**Boyan Silyavski** · 25-09-2013

Thanks for the advice. I just came from the metal shop, but they still have not cut it. However the profile seemed normal squarish, nothing unusual, so i believe that will not be a problem.

I wonder guys what are you constructing with 100x100x10

?

**ImanGH** · 11-08-2016

Originally Posted by Boyan Silyavski

Waiting for the square rails and ballscrews purchace, made me play again with the design. Decided to stuff all the electronics inside the body. Due to various reasons like avoiding
10 Neutric connectors sticking out at the back, cables, enclosure and so on. mainly because i live at the seaside so connections always give me trouble and i have to glue my connections with hot glue.

Decided also to make the structure from 60x60 4mm at the important places and 3mm at the no so important. But what ever i did i couldn't figure placing diagonals so i finished with rigid square design and 100kg structure. more or less 18meters of steel. I think i overbuild it a bit.

Another decision was to make the bed deep enough so there is no need to change spindle position. Instead a wood bed would be fitted so the spindle works at normal position and only when necessary to remove the wood bed, not move the bed of the machine or anything.

Hope that structure is strong enough, cause tomorrow will order the steel.

If somebody sees something wrong, please tell me until is time, he he.

Hi Boyan
My name is Iman and I want to design a gantry CNC. but i dont have enough data. is it possible to send me your cad design? and introduse some reference about design cnc gantry?
Thanks

**Boyan Silyavski** · 11-08-2016

Originally Posted by ImanGH

Hi Boyan
My name is Iman and I want to design a gantry CNC. but i dont have enough data. is it possible to send me your cad design? and introduse some reference about design cnc gantry?
Thanks

the design is free in the open source section of forum

http://www.mycncuk.com/threads/6979-...Machine-Design

About reference? Start your own build log thread, ask there questions, people will help you. Without knowing what you need, seeing your particular design drawing, working area, materials to be used, what is the main purpose of machine, knowing how much money you are going to spend, nobody could give you a good advice