welding steel base or just getting aluminium extrusion

got quoted £2080 to supply and weld this table which a abit on the high price tbh :( i know most of you prefer steel due to it being alot cheaper but surely making the table out of aluminium extrusion isn't going to cost me £2080. if it wasn't such a large table i would try myself but i just aint got the confidence on welding such a large frame.

Looking at video's of people putting aluminium frames together just looks like fun and easy enough to do but then i have no idea on what methods they took to make sure they had fully flat extrusions for the rails to go on. i know on steel i was going to use epoxy resin but what do you do on aluminium?

sorry for the questions guy's i just need to start cracking on now otherwise i will just keep listening to my partner nagging telling me its just another fantasy isn't it :sorrow:

Attachment 23314

Quote:

---

sorry for the questions guy's i just need to start cracking on now otherwise i will just keep listening to my partner nagging telling me its just another fantasy isn't it

---

No prob with the questions but I might be a good idea to keep them all in one place. ie in the same thread:cower:

noted Clive :)

I would get another quote on the welding reefy, but it could be that half the price is for lifting and transporting :dejection:

well to be fair he has been the only one to actually get back to me with a quote lol, the minute i mention it needs to be perfectly square and properly made they run lol.

would it be justifiable to use heavy extrusions for a more rigid strong frame? the price difference is huge but dont mind paying for it if its a plus side for the machine.

90x90 10mm slot light version
£122.85 18.9kg

90x90 10mm slot heavy version
£198.75 31.5kg

both 3000mm long

Quote:

---

Originally Posted by reefy86

would it be justifiable to use heavy extrusions for a more rigid strong frame? the price difference is huge but dont mind paying for it if its a plus side for the machine.

90x90 10mm slot light version
£122.85 18.9kg

90x90 10mm slot heavy version
£198.75 31.5kg

both 3000mm long

---

In one of your other posts did not you say you would be happy with a 4' x 4' machine!! or are you set on a 8 x 4?

bigger machines are generally much more difficult to build and thus more expensive.

Have a read through some of the very good build logs on here as that might help.

doesn't seam a bad price to me when you consider the time and material costs. There has to be 500+ in materials and if you want it perfect then your going to need to pay for skilled labour. using 90x90 ali its going to be at least that maybe more!

forgot to mention about that clive, im sticking with the 8x4 because either way it was the width i was having a problem with not length so even if i went 4x4 i would still have the same problem but thats all sorted now and i am sticking with a 8x4.

Removed.

well considering at the moment so far its at £2600 and thats without the bits and bobs to connect it all so i am looking at £3k for 90x90 heavy. And clive i have seen some builds but nobody mentions what sort of extrusion they use in the build. i have even googled it but i am struggling with so many different types to choose from. it looks as if Bosch Rexroth are the best quality but not sure about the ITM range. the ITM only goes up to 8mm t slots where as the BR does 10mm and then there is the light or heavy.

on the cncrouter.com they do the 8x4 pro kits and you can buy the bed frame only for £600 and that machine seems to have good feedback for quality so my guess for that price they have used the lighter extrusions and looks as if they are using the 45x90 but then 45mm seems flimsy.

are most of you bald by any chance? its very stressful lol.

ill keep scrolling the forums and see if i can find anymore info and idea's :)

Quote:

---

Originally Posted by spluppit

I have not seen other threads on this but what is the overall size and the size of the box? Is there any reason you have made this frame in a format which is basically 2 squares/rectangles joined in the middle?

In this one i produced some years ago you will see the box runs full length then all cross members and infills added after. This is the standard format used in industry and how designers would produce a frame. I have made many like this the years on a slab (large surface plate, not a welding table) This ensures the best flatness possible within the constraints of the material.

Attachment 23320

If your frame is as big as it looks and they have a slab that big, then its a fair price in my view if those boxes are as big as they look. Also the way you have designed it as mentioned as 2 squares joined has not helped the costs, it makes it harder to keep it as flat as possible as apposed to having the box run full length,

---

No reason other then recommendations which proves to be very strong and sturdy, but for those who can weld its not so much of a trouble with mild steel being very cheap but for me having to find someone to weld it for me then all those pieces to weld is costing a fortune.

I see good old Dean is famous in the united states too :)

Attachment 23322

Removed

I'm going to go down the aluminium extrusion route after all and for a few reasons, the obvious one is i aint welding all that steel and i defiantly haven't got the funds to pay someone that amount as well as having the funds to pay 3 months upfront deposit on a new workshop unit and then the frame on top lol. I know its worth the price what the guy offered but i just can't afford it on top of everything else.

Now there is 2 options and option 2 does have diagonal support i just couldn't be bothered to add them in lol

option 1

copy the cnc pro kit 4896 from cncrouter.com (frame bed only) costing me just under £1k which is using the 40x80 profiles but the heavier ones

option 2

80x120 with less profiles then the 40x80 costing just over £1k but these are the light profiles not the heavy ones

i know its way more expensive then steel but i am not as lucky as most of you with welding skills and i can always add to the frame once more funds come in. personally i prefer option 2 as it looks way more solid but would like your opinion and if and where i should add extra support.

Appreciate the help guy's


Attachment 23323
Attachment 23324
Attachment 23325

I look after a machine that is built similar to option 2 built by a company with initials like MD:miserable: and it does work and cuts 8x4 sheets of 6mm MDF all day.

the rack & pinion seems to be fine and the rack is mounted inside the slot on the side of the top rail.

Have you thought how you are going to drive it and what motors etc.

Quote:

---

Originally Posted by spluppit

I know you are going on other designs but all this generally means is.... someone that isn't an Engineer or a fabricator came up with a design, made it and it worked, and that then sets a president others follow. That does mean mean its good design all it means is someone proved it worked. In the same breath if that design had been done by someone with a lot of experience then that would have been the president and far easier to get a lot better result.

---

You'll not last long in the DIY CNC world with sensical observations and comments like that ;-)



Listen to what sluppit has said.
I took one look at your design last night, and immediately wondered how many tonnes you were planning on having on it, and why it wasn't using full length sections on the long edges. It looks to me like you've just kept adding bits, without really thinking about why you would need to add them, and ended up with an over complicated design.

Quote:

---

Originally Posted by Clive S

I look after a machine that is built similar to option 2 built by a company with initials like MD:miserable: and it does work and cuts 8x4 sheets of 6mm MDF all day.

the rack & pinion seems to be fine and the rack is mounted inside the slot on the side of the top rail.

Have you thought how you are going to drive it and what motors etc.

---

yeah i already have 90% of the electronics planned out with the help from Dean using high quality ballscrews/hiwin rails/rotating ballnuts for the long y axis. even though i said i was going to copy of cncrouter.com that was just for the bed but everything else will be better and defiantly will be wanting to cut thicker then 6mm all day lol :)

Quote:

---

Originally Posted by m_c

You'll not last long in the DIY CNC world with sensical observations and comments like that ;-)



Listen to what sluppit has said.
I took one look at your design last night, and immediately wondered how many tonnes you were planning on having on it, and why it wasn't using full length sections on the long edges. It looks to me like you've just kept adding bits, without really thinking about why you would need to add them, and ended up with an over complicated design.

---

it wasn't complicated until i finished in solidworks and then reality hit :)

Removed.

if it was cheap enough to make mistakes then sometimes its good to make them before getting the right advice from here, That way you get to learn what works and what dont work but unfortunately this is a hobby that is just too expensive to just ignore good advice. I don't think dean realises just how much i appreciated all his help from emails out of his own time which i have kept and still read them :)

Removed

£1580 for the one you have provided mate so still expensive

Removed

Whats with the attitude you keep giving me? don't want to sound like like a twat to you and i do appreciate the time you are giving to help but i didnt ask you to make or do anything for me. i have said many times i am going the aluminium profile route because either way its going to cost me around £500 for the material and then there is no way someone will do that frame for me for under £500 and i don't blame them. the design you shown me looks alot more simple then mine and you said to use 80mm instead of 90mm so that should of been cheaper. The guy who has quoted me is off facebook that got recommended to me, so i sent him that as a rough example and he quoted me £1580 without the extra bits i would of added on. like i said earlier because im not as skilled as most of you by the time ive payed someone to do it and bought all the material its going to cost me almost as much as what the aluminium profiles is costing. the whole point of going steel is because its cheaper and i know its more rigid but the aluminium also has an advantage for resonance so either way i choose its going to cost me the same or maybe a little more.

again i don't mean to sound harsh but i didnt ask you to send me any files or do any work and i already said a few times im going with aluminium but you keep posting with more steel advice :)

My mistake. Offending posts removed. I wish you luck with your build.

I wasn't offended and you are all more then welcome to give any criticism, i was just trying to explain that i didn't expect the cost of welding to be so expensive as i know nothing about welding. my budget for the frame is £1100 and it would of been more if i didnt need to look for a new workshop. I also understand what you mean about why i don't get replies back from companies with an over the top frame on top of asking for perfection and i didn't ask any more companies for a quote because i had already decided to go the aluminium route but i was curious to see what the guy would charge for your frame you sent me. so i do apologise for any confusion in any of this and i really do appreciate what ever advice good or bad.

Welding and all measurable physical work is going through the roof price-wise, £10 per inch is not now uncommon.
I was quoted £200 for a small (40mm x 200mm) welded patch on the inner sill of my wife's 20 year old Mk1 MX-5, as soon as I started talking about job quality and "semi-restoration standards" i.e. not just welding a patch across everything visible the guy looked a bit ill - I did it myself as in a previous life I was a panel beater and worked in classic car restoration (photos on request).
I'd suggest buying a welding set and learning to weld, then doing it yourself, that way you'll have the equipment and the skills, if you pay someone else all you have is their invoice. ;-)

ill try and look for a frame that is more suited and price it up and see if its worth while just risking it. Dont blame me when im posting on here every single time i press that trigger lmao :)

Can you not see this as an opportunity to gain equipment and a skill set and still spend less money?
I've taught 3 of my friends to MIG weld to a good standard and to understand how to set up the machine for a variety of jobs in the last 2 months, one is doing a very nice job of customising a motorcycle frame, his welding is now very good,
Regards,
Nick

if you was to ask me to weld a steel shelf up or repair a car exhaust then id happily try learning it but its getting the frame squared perfectly and then making sure the steel that the rail goes on is welded down with no twist ect that scares the shit out of me. i see these sort of comments that makes me understand and feel better

"Clamp your work to a surface that will keep it square, use plenty of tack welds, and dont weld opposite corners because it will tend to push your square into a paralellogram."

and then this straight after that buts me back to square one lol

"if you have a part that must be square, simply make a lighter root pass to hold everything in place, then fill the joint up to a level that is nessecary.

Also if you are welding thick metal, pre heat it, it will prevent cracking of your welds, and it will prevent "pulling" by the weldments."

would this be useful i just heard of it watching a video but not sure of the accuracy

Attachment 23333

So design your base so that the two rails which must be in the horizontal plane bolt to it!
Hey Presto!
No machining!
No Epoxy!

If you pay for fuel I'll provide use of my Optical Clinometer which is good for ridiculous tolerance when you level the feet for the base and then set the rails.

appreciate that mate ill get back to you on that one once i have the frame partially built. ive just come across this and would like to know if that frame is capable of doing what he says he is doing? ive never seen a table like this before what do you think. also would 80x80x4mm be thick enough or does it need to be 5mm

http://www.oneoceankayaks.com/madvac/madvac_index.htm

Quote:

---

Originally Posted by reefy86

if you was to ask me to weld a steel shelf up or repair a car exhaust then id happily try learning it but its getting the frame squared perfectly and then making sure the steel that the rail goes on is welded down with no twist ect that scares the shit out of me. i see these sort of comments that makes me understand and feel better

"Clamp your work to a surface that will keep it square, use plenty of tack welds, and dont weld opposite corners because it will tend to push your square into a paralellogram."

and then this straight after that buts me back to square one lol

"if you have a part that must be square, simply make a lighter root pass to hold everything in place, then fill the joint up to a level that is nessecary.

Also if you are welding thick metal, pre heat it, it will prevent cracking of your welds, and it will prevent "pulling" by the weldments."

---

One suggestion why not buy a 2nd hand machine and do it up, then you haven't got to make a frame.

ive tried looking mate but cant find any

The key to welding something well, is preparation.
All bits have to be a good fit before welding, it's then a case of tacking, and alternating where you weld to balance out any twisting.

Something you really have to appreciate, is just how much weld beads will shrink/pull when cooled, which is why you want a good fit, and do alternate welds to balance any pulling.

Alternatively, you could just bolt it all together, however you run the risk of knocking it out of square.

well after watching a lot of youtube video's i am starting to come up with a method and feel a little better however after getting the materials and all necessary equipment/tools then its still going to cost me £1k+ anyway but i suppose i learn a new skill trade in the process.

anything wrong with this frame and is the diagonal supports ott? i will be adding adjustable feet on aswell

cheers

Attachment 23334
Attachment 23335

For what's it's worth I was not confident welding either, so made mine in several welded parts which where more manageable then used bolted connections to fix them together and finally tacked it together once it was all squared up. It is actually not that critical to have the frame perfect as you will most likely need to level it with epoxy anyway and so long as the rails are parallel the support under them does not need to be perfect. Basically what I'm saying is I'd have a go yourself and spend the money you save on the other parts!


Sent from my iPhone using Tapatalk