Tiddy CNC.

**CraftyGeek** · 26-09-2013

Tony - it may be worth seeing if you have another local steel yard near you. My local supplier charge £4.1 +VAT per meter for 50x50x3 (£147.60 for 30m) as a base price & charge less than that if you order a reasonable quantity. I also get them to cut some of it to size for me - depending on quantities, they charge 50p per cut or less...this means I can fit it in my car & pick it up myself removing the delivery charge as well as saving me time cutting stock to size.

**Boyan Silyavski** · 26-09-2013

You guys are lucky to live in UK. Here in Spain i think in kg. Roughly any profile costs 1kg=1euro at the big warehouses. Unfortunately no near where i live and they don't cut to size. As i don't have a band saw i have to order from the local metal shop. If you befriend them they cut to size and sell it for 1.50 the kg with the work. if you don't know them they sell it for 2euro per kg and you pay the cut extra and that if you are lucky that they pay you any attention...

Hence my designs are influenced by the KG and by the 6 meters length. Guess who i will be bringing some beer tomorrow

**TonyD** · 26-09-2013

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I've been caught by the CNC bug again :)
Silyavski emailed me a model in Sketchup to play with which convinced me to ditch Visio for my drawing and start again in Sketchup. As I tried to explain to my wife "the guys on the forum made it stronger, cheaper and lighter", which is I guess the power of good design. Trying to manage the constraints of cost and size I ended up going for 80x80x3 due to an inherent constraint with my Y Axis (which is built), which then left me trying to get the frame out of only two lengths of 7.5M stock, which led me in the end to cut the legs down to 350MM from 500MM. I phoned around today and a local Steel supplier quoted me £50 ex Vat per 7.5M length of stock. Now that its down to just £138 with VAT and delivery I'm happy. Bonus is the machine can be carried through a doorway so no bolting. So thats my current plan. Thanks for all the input, any other comments welcome.

**Boyan Silyavski** · 26-09-2013

Hi Tony,
i forgot to tell you but you went to exactly the same conclusion like me. The 80x80x3 is the size of profile that is at the golden middle point for weight and strength and value, also permitting this type of design. Great that you figured it on your own.

Today i went after work to the lazy guys at the metal shop and urged them for my profile. After helping them to cut i figured one point more. Its not a real necessity though. As i have ordered 1x 6m new profile and used some scrap they had, there was i piece of 100x100x4. So i figured at the last moment that the 80mm pieces could be even stronger if made from that. Ask them if they have by chance some scrap 80x80x4 just for the 80mm pieces. It will not raise the price. Just give it a try.

Hey, now i want small legs for the machine i am building

**JAZZCNC** · 26-09-2013

Tony The design would benefit from one more support for bed has the centre distance is on the wide side and could cause bed flex.
It also definitely needs some triangle braces in the corners to help hold frame square.

**TonyD** · 27-09-2013

Thanks Jazz. I skimped on the extra rail in the design to keep the Steel costs down to two lengths. What I'll do is find some smaller sized box section for the central bed support, put two or three support rails in there (depending on size) and use the existing single span of 80x80x3 to create the support triangles at one end. I guess at this point I could go for triangles on the 'fixed' end or just move the central bed support rail to the same height as the top rails to create a U shape. I'll draw them up shortly and ask for comments.

**TonyD** · 01-10-2013

I have to admit that I'm not planning on cutting or welding the frame for my machine myself. I dont have the kit, or a suitable space to make the frame. So I'm off to see a recommended chap locally who has agreed to cut, weld and paint as per the attached. Not sure when it will be done yet, should confirm things by the end of the week then its just a matter of hauling 136KG's of frame to my study up the stairs.. :)

**Boyan Silyavski** · 01-10-2013

Wise decision if you don't have the means. I welded mine with my new welder this weekend. I fiddled a lot, as my first real weld and had to wait for a friend to take it of the welding supports and bring it inside the garage. You will be surprised of the robustness of the design. Dont forget what i suggested you in the email, spend 5-10 pounds more and weld vertically a 5mm or similar whatever flat bar plate at least along the middle profile of the table bed for vertical reinforcement. If it was me, i would weld on the 3 of them. Just for the sake of extreme robustness. Of course, depends whatever you intend to use as table bed. Also these bars can be bolted later if needed. However with them you will have astonishingly minimal overall deflection/less than 0.05mm i believe/

I don't know about your gantry and Z but with this you can do aluminum on the breeze

Whatever, looks very nice!

**Stupoty** · 31-12-2014

Originally Posted by CraftyGeek

Tony - it may be worth seeing if you have another local steel yard near you. My local supplier charge £4.1 +VAT per meter for 50x50x3 (£147.60 for 30m) as a base price & charge less than that if you order a reasonable quantity. I also get them to cut some of it to size for me - depending on quantities, they charge 50p per cut or less...this means I can fit it in my car & pick it up myself removing the delivery charge as well as saving me time cutting stock to size.

Do you have the name of the stockist, thats a fairly good price :)

i always check metals4u.co.uk for steel and their about £60 + vat for 6m

stuart