[Tony_Stark]

It travelled very fast peter.

[peteeng]

Hi tony - Yes much faster then the first lot, plus they sent it free freight! Peter

[peteeng]

Morning All - Been working on the workshop. Painting the floor.... also the Mens Shed opens this week so can get back into YaGs build. Need to get the metal parts on order. I've decided to pull down BrevisNo2 and use its electronics for Yag No1. Got to get the floor finished then can start on the shelves and then a BIG machine...Peter

[peteeng]

Evening All - Today I levelled the top of the walls to the best I could do with the lap and engineers level, quite good I think. Checked for wind with string and did the best I could with straight edges and levels. Happy its about as good as I can get with the tools I have. I received another quote for a laser geometric measurement system today and it was $42,000 AUD. Must be something out there <$5k ?? I started getting the workshop organised and turned on the laser. It manually does everything but have not turned on the laser yet till I get the chiller functioning.... get some plumbing tomorrow... connected the smoke extractor to the wrong side and blew crap everywhere from within the machine...

So much to do. Now to get serious with YaGs metalwork... got to get it on order Peter

[peteeng]

Hi All - Got back from a short trip and my main computer won't boot!! Have to take it to the tech. It has my CAD system on it and project data so a bit stalled at the moment. Peter

[peteeng]

Evening all - Turns out the motherboard has died so they ordered in a similar one. When rebuilt the USB ports didn't work proper and it had trouble turning off and on. So they are reinstalling windows... More news tomorrow. Then I can get back to YaG. I have started migrating software over to the new workstation. Have to deactivate and reactivate stuff and get new software keys. Takes a while to get everything in order... Peter

[klaas123]

With Windows 10 you can you can put the old SSD or HDD in a new computer, it will boot. After this you use a free program called Driver Booster from Iobit.com, it will install all drivers for you..

[peteeng]

Hi Klaas - Thanks for that but its all done. I expect the tech uses something like that. I picked the machine up and I'm setting up the programs etc now. Your cnczone mail is the top one through... aren't you lucky? Peter

while the tech was at it today I cast some epoxy alox. This is the way I want to go in future machine parts. Or alox/UHPC.. I'm very happy with the cast. In theory its 99GPa modulus & same density as aluminium....will test it to see.

Now I have to put in a big effort to get YaG rolling again...

[Zorbit]

Does mixing grit and aggregate with the epoxy add much air ? I'm thinking of micro-bubbles on / in the surface irregularities released into the resin.

If so, how will this affect the mechanical properties ? Is it worth comparing two pieces, one vacuum degassed after mixing ?

[peteeng]

Hi Zorbit - The usual approach of mixing epoxy and aggregate includes a lot of air during mixing. Degassing laminating resins is very difficult. Degassing aggregate mixtures is very difficult due to the long pathway for the air and the hydrostatic pressure gradient. So DIY EG people usually do not degas. My approach using infusion self degasses. The approach of dry stacking and pouring thin epoxy in, self degasses. On the point of does entrained air reduce mechanical properties, yes it does by a small amount. There are two sources of gas in epoxy 1) mechanically introduce air due to mixing and transport 2) saturated gases. You need very deep vacuum to remove saturated gases and you need special techniques (thin film, stream droppng are a couple). Degassing in a bucket will remove most of the mechanically introduced air. Typically I'd degas the warm Epoxide not the hardener then mixing carefully after the epoxide has cooled. For the DIYer I'd not bother with degassing it won't change the material stiffness significantly and the strength delta is not enough to worry about in machine parts. I have been involved in high voltage insulator parts and those required very good degassing to meet the strength and insulation requirements not easy to do in your garage.... Peter

[peteeng]

Morning all - so here are two "cups". The RHS is 58% by volume alox the LHS is 51% alox 11% aluminium and 39% epoxy. ie 62% solids. Which is 18% epoxy by weight addition rate to solids for both casts. Both were achieved by placing dry material in the mould then pouring very thin epoxy into the cup until filled. The LHS with the aluminium grit shows the grit has segregated. The AL is the grey patches. The LHS epoxy is clear, I added white pigment to the RHS cast. From this I'm not inclined to try to make a graded batch. The simple one grade is the go. You can do the same thing with sand, much easier I think then mixing sand and epoxy... then shovelling into a mould... Peter

beware weight ratio comparisons as they depend on the densities of the aggregate. The most quoted "10%" usually is too dry and the maker accepts the resulting porosity as a cost down strategy.

[peteeng]

Hi Zorbit - The real killer for mechanical properties with this sort of thing is the moisture layer around the aggregate. When I started infusing boat laminates we achieved significantly stronger laminates then we ever had achieved before using std vac bag methods. Took me years to figure out why they were 3x stronger. Under vacuum the water was being boiled off the fibre surfaces so the resins could stick to the materials very well. EG has quite damp materials so I expect the bond is poor but good enough. If your really chasing strength then you need to go to vacuum processes to remove all moisture and air from the job before you introduce resin.... Peter

[kinghong1970]

Awesome build log Peter!

[peteeng]

Hi KingH - Thanks for the support. Been checking the metal bits and getting the structural parts order underway. Have to do this pronto as I have sold a router off the plans and they are ordering the machine base material next week. So I'll have to stay ahead of them!! Peter

[peteeng]

Hi All - A good day for Yag. I checked the gantry foundation parts and the motor mounts etc and placed the order for the top plate and spacer that transitions the timber base to the metal gantry. Now need to work through the structural parts and check all the holes agree!! Originally the top plate was timber but the potential forces in this area are large so I decided to go aluminium. They will be nicely anodised so will be a good looking foundation for the machine.. Onto the pressed metal parts. Peter

[peteeng]

Hi All & Sundry - Well the machinist didn't like the odd size of the foundation plate. Would have to have it cut from plate somewhere else and it got sticky. Its 2mm oversize off the wall to create a shadowline and to provide some wiggle room for assembly. Hmmmm so I rang the machinists Al supplier and they had 100x12mm 6061-T6 extrusion, which would sit on the wall exactly (no shadow line or wiggle room) So I shuffled the parts around and fitted onto that. A better solution into the future, updated the wall dwg with notes about important dimensions and sent the updated dwgs to the machinist. So they are on their way!! Yeh, now onto the checking gantry parts, mainly that the holes agree, so many holes...... Peter

[peteeng]

Hi All - started setting up the controller for testing but it has "gnd" and 36V rather then + and -. Looked in the manual no luck, are PCBs negative ground? I'll track the pcb and look at the diodes... I have let the smoke out at this point before don't want to do it with this one....Peter

[peteeng]

Hi All- I looked at some other wiring diagrams and connected it GRD negative and no smoke!! Now sorting out the pins... Peter

[peteeng]

Hi All - I set up a simple square program and ran the system for a while. I set the controllers at 25% current, 1/16 usteps and all looked good running some NEMA17's I had. Then the Y axis stopped working, that's odd. Could jog it around under manual but would not run in a program. So I left it for a while came back and started running again but Y got noisy and unreliable then POP and the smoke escaped... bummer. Plus the PS died ... So I sent a note to the board suppler and the PS supplier requesting replacements, shall see what transpires. I shall use the board and set the B axis as a slave Y axis and see if I can use the board that way... But I think in future I'll go the separate parts route. Peter

[mactec54]

Hi All - I set up a simple square program and ran the system for a while. I set the controllers at 25% current, 1/16 usteps and all looked good running some NEMA17's I had. Then the Y axis stopped working, that's odd. Could jog it around under manual but would not run in a program. So I left it for a while came back and started running again but Y got noisy and unreliable then POP and the smoke escaped... bummer. Plus the PS died ... So I sent a note to the board suppler and the PS supplier requesting replacements, shall see what transpires. I shall use the board and set the B axis as a slave Y axis and see if I can use the board that way... But I think in future I'll go the separate parts route. Peter

The power supply may just be a fuse, lift the cover they usually have a fuse

What is that Motor Driver Board you have