Hytech2k published a new build:

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LOL, I think Openrail is the way to go, less issues with with sawdust.. I'm thinking the side plates might be 1/2 plate and 3/8 for the x axis... The HUGE improvement will be the true rack and pinion, eliminate the problems with stretch, deflection and debris fouling the belt. The rack and spur gears I ordered came in today but were the wrong ones, looked like they would be for a toy, reordered and hopefully have a working prototype plate put together soon. Did get some proper shoulder bolts and 2 different bushings (Oilite and Super Oilite) for the stepper drive plates. I'm getting ready to cut out the side plates and the X gantry carriage plates tonight... I'll post some photos when I get the done..

 

I'm just using the phenolic to prototype my plates, these won't be on a cutting machine, just to check fit and operation. I brown plates are a CE (Canvas laced) Phenolic and the green is G10. I get it from here:

http://stores.ebay.com/norvaplastics?_trksid=p2047675.l2563

Good prices I think and they combine shipping...

I believe I paid $12.00 for a 12x12 .375 CE and $10 for the 12x12 G10

 

I get alot from McMasters, good selection but wow G10 1/4 12x12 sheet 36.75 lol, i'll stick with 12.00 for my Ebay guy... I don't mind offcuts... But the XX Garolite wasn't too bad...

**edit.... sorry I miss spoke, the CE grade i'm using is 32.51 at McMaster, 10 bucks on Ebay.....

 

McMaster Carr, I'll have to fashion a mount for them but it shouldn't be to hard... The spur gears are the hard part to find in sizes for my steppers.. Misumi came through for those..

 

CNC router parts has rack clamps that are pretty neat, i'm just not sure they will fit the vslot extrusions....

 

I'm going in about the same direction, I'm using 1/4" x 1/4" 24 pitch 14.5 degree pressure rack for the gantry and 1/2" x 1/2" 20 pitch 20 degree pressure rack for the Y. I'm also attaching them to backers but 3/4" wide 1/8" thick steel. My attachment method is to drill 7/16" holes every 6" through the backer directly behind where the rack will be placed, i'm having a local welding shop MIG weld the rack to the backer from the backside through the hole. So basically it will be spot welded every 6" along it's length with no welds showing from the front. Then have a second set of holes drilled to mount to the extrusion via bolts and t-nuts. Hopefully, that's the plan.

 

Don't go accusing me of be inventive. I'm not too worried about distortion too much, they can put a wet rag on either side of the weld to keep it cool. The large rack is .5 x .5 so I think it could handle the heat, but the little one might need to be tig'ed...

 

LOL when you click the link to read the PDF it kicks you over to cncrouterparts and opens.... Fineline either distributes for cncrouterparts or is another branch. But looking over the PDF dimensions they won't fit, the tab that locks in the extrusion is .320 wide, I put the calipers on mine and come up with .2455... BUT a crafty fellow could resize that clamp to fit a .25 wide slot, incorporate the 60 degree V to match the v-slot profile, and make the holes smaller for M5 hardware.

 

Now looking over their site it's mostly all cncrouterparts products, must be a distributor or something...

 

They used to offer that same rack, back when I bought my drives from them they carried it, but now have changed to rack mounted on a pre drilled backer... They change quite often, I'm probably on REV 4 or 5 of the Pro Drives....

 

I looks alot like Fineline has alot of the older products cncrouterparts used to carry... It's like the outlet store for cncrouterparts older discontinued items..

 

Whipped these prototypes up real quick, they fit the Misumi extrusion just fine but the locating tabs are to tight for the 8020 metric extrusions and I still have to add a chamfer and fool with the depths to adjust it to fit the V slot extrusions... But coming right along, probably have it worked out by the end of the day... Oh and this one is designed for 1/4 x 1/4 rack... I'm using them on my gantry to hold the 24 pitch rack I have on hand.. I'll be doing another for 1/2 x 1/2.

 

Ebay usually, I have a few people who sell remnants with free shipping...

 

http://stores.ebay.com/metalremnantsinc?_trksid=p2047675.l2563

 

I'm using a good dust shoe and large dust collector now so debris is not so much of an issue anymore. At the price point I sell my signs, HDU isn't really an option. Plus my customers are looking for that rustic country look, hard to get from signboard. I cut at good speeds and feeds on my bigger machine, the little one needs to keep up otherwise I'll have to do custom toolpaths for every sign I make, and that just won't work.