I'm still getting the best part of 7 teeth engaged and 5 fully. According to Jonathan this should be sufficient. I'll have a think...🤔 as always - appreciate the critique even if it does mean more redrawing (again and again!!)
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I'm still getting the best part of 7 teeth engaged and 5 fully. According to Jonathan this should be sufficient. I'll have a think...🤔 as always - appreciate the critique even if it does mean more redrawing (again and again!!)
Hmmmmm.......Quote:
Originally Posted by JoeHarris
Haha like your confidenceQuote:
Originally Posted by njhussey
Attachment 17555
That's how I've bodged mine in, at some stage I'll design a neat back plate and use the machine to cut it.....a bit Heath Robinson, but it works :thumsup:
Attachment 17561Attachment 17562If at first you don't succeed... be glad you modeled it first!
That looks loads better Joe n1!
Cheers Lee!
That looks good Joe :)
New you would get there in the end Joe its tons better now:applouse:
That's it Joe.:thumsup:
Cheers guys. When measuring the belt to order a bespoke length, do you measure one side or the centreline or what? Won't make a big difference I guess but if there is a right way I'd like to know.
You build it then you get a piece of string and rap around pulleys and take to belt place and say I want one that long.!!:encouragement: (or then measure it's length.)
Ha ha. Love it. Yes ok it's not like me to over complicate things!Quote:
Originally Posted by JAZZCNC
Z axis progress pictures. Attachment 17826Attachment 17827Attachment 17828Attachment 17829
Very nice as always Joe. Great idea on the spacer plates to save pocketing the ball screw BK mounts although it does push the spindle further out slightly. :thumsup:
hopefully be starting my own build shortly ,capable of holding an 8*4 sheet.,,,,,,thinking of going with rack and pinion,,,,i am looking on the net for extrusion suppliers in the uk,,,does anyone have any recomendations on material suppliers..i am located in n.ireland.
Hi and welcome to the forum it would be better to start your own thread so as to keep all the questions you might have in one place.Quote:
Originally Posted by voyager1972
Have you built a machine before? and have you decided what you need to cut?
Why not put a design up of what you would like to do. Good luck with the build.
I have finally levelled the frame as best I can - in its "final" position. I decided to tack weld the beams which will support the x rails (now I know they are as parallel as they ever will be) prior to pouring the epoxy and most significantly I have started to make the mdf channels in which to pour it.
I still need to grind the mill scale of the top surface and for the weather to warm up! Attachment 18353
Btw I have decided on 1no 30mm wide bridge and the channels for the rails will be 40mm wide (for 20mm rails) I hope this will be wide enough to avoid meniscus problems - I'm trying to get the most out of my tin of west system!
Watch for shrinkage at the ends of the rails, mine were slightly lower at the home ends...dunno why! Also double and triple check the seal between the MDF moat and your rails, leaks are a bugger to stop! If possible line the MDF with packing tape as it'll make getting them off so much easier...much less work with a file :)
Thanks for the tips!
Joe I did not have any shrink problems at the ends on mine but do put the effort in to stop any leaks you will be surprised how easy it is to get one, a small bead of silicone is the key
I sealed my moats by running a small amount of epoxy along the gap first. Small amount and it doesn't run through but will cure in the gap and stop it leaking when the full depth goes in a day or two later.
been looking at nema 34 stepper motors online,,,,,would they be suitable ?,,,,,i plan to be machining sheet material like mdf,,,melamine,,,oak and ash ect.. also i see the motors are avalable with differant holding torque......would the higher values be advisable.
It is impossible to say what size of motors you require without giving details re your machine. It might be a good idea to start your own build log to keep all the questions in one place.Quote:
Originally Posted by voyager1972
Clives 100% correct but it's also 95% chance they won't be suitable for few reasons. First reason high chance they will be high inductance motors which mean you'll need expensive high voltage drives.Quote:
Originally Posted by Clive S
Second reason is they'll be all wrong for your machine unless large or heavy load to move.
Jo be careful you have enough epoxy because it's proper ball ache if you run short. However I know 1ltr should be enough for machine your size so shouldn't have any trouble.
Really make sure you seal it well because it's amazing how epoxy finds leaks and they don't always appear instantly so keep checking and be ready to make repairs. Putty is handy stuff to seal quickly.
Attachment 18386
Surface ground and scored with sandpaper. Dams almost complete... Attachment 18387
Looking good Joe....looking forward to seeing the pour!
Me too. Bought some silicone sealant and found an oil radiator donor! Nearly ready...Quote:
Originally Posted by njhussey
What's the oil radiator donating?Quote:
Originally Posted by JoeHarris
To heat my workshop... Someone is lending me a couple of them. A minimum of 16 deg C as a constant temp is recommended and West System state: "As the temperature drops, epoxy becomes proportionally thicker, reducing its ability to flow out." They also state that air bubbles are more of an issue at lower temperatures.
Hi Joe
If you have a vacuum pump you could knock up a degassing pot, i use an old pressure cooker.
Regards
Mike
Hot air gun across surface would usually deal with any bubbles.
Ready to pour! Attachment 18429 I made some little brackets to hold the mdf in place Attachment 18430 sealed both sides with silicone so hopefully no leaks! Attachment 18431 and heat gun and Vaseline at the ready! Attachment 18432
Best of luck, looks like you've got everything prepared though so I'm sure it'll go fine.
careful with the heat gun joe you can easily cause hot spots which harden at different rate. Only a quick flash is needed and only if really needed. Few air pockets won't hurt anything.
Not quite sure what the vasoline is for thou.?
Vaselines for the same as heat gun apparently "Some like it Hot!"Quote:
Originally Posted by JAZZCNC
Cheers Dean, I will take it easy on the heat. The Vaseline was for the mdf sides to act as a release agent... I think Clive suggested it?Quote:
Originally Posted by JAZZCNC
This is why you want slow cure epoxy - this a time lapse- https://vimeo.com/166112200 the movement is barely perceivable in real time. Attachment 18448 well it's done. Now we wait... Attachment 18449
Great stuff especially the time lapse video. It might be worth keeping the bridge between the 2 rails in place during initial setting up if you need a datum to DTI off to align the gantry Y rails - depending on the gantry rail design you've decided on