VEXpro 2015 Product line launch

[AdamHeard]

Originally Posted by Mr V

Yup we will just have to switch to 1/4-20, if our coach decides to buy some. The bolt all the way through isn't practical for a lot of our applications, we would need to stock a number of different fairly long lengths. The other issue is that I like having the "other" end of the shaft retained which would not happen with a through bolt.

For stand offs where we do run a through bolt it will be convient but in many of those applications we still did the tap both ends for #10 so that one side, again so that one side will be retained when doing repairs.

I'm not against the hole in the middle, in fact I think it is great as it will help teams that don't have a lathe. I'd just prefer that it was sized to tap for #10 or for a #10 thread forming bolt, since that is what we use everywhere and we haven't used 1/4-20 in a while.

I'm Mr #10. It's my favorite fastener, and we've used it forever.

That being said, the more COTS teams are in 1/4-20 land. This makes sense.

Being Mr #10, I'm STOKED about the hole as we'd never use a bolt to retain the items on a shaft... but these will make great heavy duty standoffs with the hole already drilled.

ThunderHex is my favorite new product, and I think they did it perfectly. Now time for 3/8" thunderhex next year

[Nemo]

Originally Posted by AdamHeard

I'm Mr #10. It's my favorite fastener, and we've used it forever.

That being said, the more COTS teams are in 1/4-20 land. This makes sense.

Being Mr #10, I'm STOKED about the hole as we'd never use a bolt to retain the items on a shaft... but these will make great heavy duty standoffs with the hole already drilled.

ThunderHex is my favorite new product, and I think they did it perfectly. Now time for 3/8" thunderhex next year

I'm glad other people also have nerdy feelings for their fasteners.

Those heavy duty standoffs could also be dead axles used with ThunderHex bearings. That could be pretty sweet in some situations.

[Mr V]

Originally Posted by AdamHeard

I'm Mr #10. It's my favorite fastener, and we've used it forever.

That being said, the more COTS teams are in 1/4-20 land. This makes sense.

Being Mr #10, I'm STOKED about the hole as we'd never use a bolt to retain the items on a shaft... but these will make great heavy duty standoffs with the hole already drilled.

ThunderHex is my favorite new product, and I think they did it perfectly. Now time for 3/8" thunderhex next year

I'm curious as to why you'd never use a bolt to retain items on the end of a shaft? A big reason is that it is easier to get students competent in using a bolt and Allen wrench that using snap rings and e-clips. It is also easier to get students competent in tapping the end of a shaft than cutting a groove for an e-clip or snap ring on the lathe. I don't like shaft collars because they are more expensive to purchase and add length/width that you don't need with a bolt in the end.

I'm also not a big fan of the though hole for stand offs and prefer a bolt in each end. If you have to remove what ever the stand off is holding you often just need to remove one side. So if one side is still bolted then you just place the removed piece back on and bolt it on. With a through bolt the stand offs are then loose and you have to put align them all when putting it back in place and you need two tools to reassemble. Yes during initial assembly you'll need two tools but in repairs during the heat of competition putting a bolt back in one side is quicker.

[AllenGregoryIV]

Originally Posted by Mr V

I'm also not a big fan of the though hole for stand offs and prefer a bolt in each end. If you have to remove what ever the stand off is holding you often just need to remove one side. So if one side is still bolted then you just place the removed piece back on and bolt it on. With a through bolt the stand offs are then loose and you have to put align them all when putting it back in place and you need two tools to reassemble. Yes during initial assembly you'll need two tools but in repairs during the heat of competition putting a bolt back in one side is quicker.

When you bolt all the way through a spacer you're able to make a much stiffer assembly since you can preload the bolt.

Here is a good description the concept.

You're right that a bolt on each end is often more convenient and it really just depends on what your goals are.

[AdamHeard]

Originally Posted by Mr V

I'm curious as to why you'd never use a bolt to retain items on the end of a shaft? A big reason is that it is easier to get students competent in using a bolt and Allen wrench that using snap rings and e-clips. It is also easier to get students competent in tapping the end of a shaft than cutting a groove for an e-clip or snap ring on the lathe. I don't like shaft collars because they are more expensive to purchase and add length/width that you don't need with a bolt in the end.

We have no issues teaching kids to do either of these... It's standard practice on our team and kids do both all the time.

I'm also not a big fan of the though hole for stand offs and prefer a bolt in each end. If you have to remove what ever the stand off is holding you often just need to remove one side. So if one side is still bolted then you just place the removed piece back on and bolt it on. With a through bolt the stand offs are then loose and you have to put align them all when putting it back in place and you need two tools to reassemble. Yes during initial assembly you'll need two tools but in repairs during the heat of competition putting a bolt back in one side is quicker.

We like through hole for high load standoffs, and using a nut. The chance of stripping aluminum threads out, or wearing them out through reuse, bugs us. I know that's not the greatest reasoning. Also, it's usually easier for really buried things to get a wrench in from the side on the nut, rather than a tool in on a bolt head.

You also get better clamping force, and to be honest I like reducing the number of tapped holes as, "Aint nobody got time for that" when you build in the qty we do.

Vex clearly is supporting 1/4-20 as they had to pick a size... I totally agree with that decision for the kind of teams that need this stuff most.

[Taylor]

Sorry, uninformed NEM question here:
What does the ThunderHex do that Churro doesn't? I see that the aluminum is 7075 rather than 6005, which I presume makes it stiffer. But why is it 2x the price? Is that just the nature of the alloy?

[FrankJ]

Originally Posted by Taylor

Sorry, uninformed NEM question here:
What does the ThunderHex do that Churro doesn't? I see that the aluminum is 7075 rather than 6005, which I presume makes it stiffer. But why is it 2x the price? Is that just the nature of the alloy?

As far as stiffness goes, All aluminum has pretty much the same stiffness. Stiffness is based on Young's modulus, shape & doesn't change much with alloying & heat treatment. Strength is a completely different story.

The concern I would have would be the difference in torque transfer of a rounded off hex & would the shape spin in a round bearing, making it a bushing. I have not looked very closely at this so it is just a concern, not an known issue.

[AllenGregoryIV]

Originally Posted by Taylor

Sorry, uninformed NEM question here:
What does the ThunderHex do that Churro doesn't? I see that the aluminum is 7075 rather than 6005, which I presume makes it stiffer. But why is it 2x the price? Is that just the nature of the alloy?

Churro tubes aren't designed to be used as axles. I've seen a few teams do it but they often bend them. Thunderhex has the strength of the VEXpro hex shaft but also have the through-hole and rounded corners to be used in a specific round bearing (13mm).

We used VEXpro tube axles last year for through-bolted spacers and Churro tubes for tapped standoffs. A few times we had to drill and tap hex shaft when the churro tubes weren't strong enough for our application. The thunderhex should fix this. We can also use #10 through bolts with the Thunderhex and since we are also a #!0 team that will make some things easier.

[Taylor]

Originally Posted by AllenGregoryIV

Churro tubes aren't designed to be used as axles. I've seen a few teams do it but they often bend them. Thunderhex has the strength of the VEXpro hex shaft but also have the through-hole and rounded corners to be used in a specific round bearing (13mm).

Cool. What about it gives it the added strength? Is it the cross-section geometry? The alloy? The black anodizing?

[AllenGregoryIV]

Originally Posted by Taylor

Cool. What about it gives it the added strength? Is it the cross-section geometry? The alloy? The black anodizing?

The alloy, 7705 is a zinc alloy and in general 7xxx series aluminum (zinc alloys) will be stronger than the 6xxx series which are magnesium - silicon alloys.

[Joey Milia]

Originally Posted by Taylor

Cool. What about it gives it the added strength? Is it the cross-section geometry? The alloy? The black anodizing?

It's definitely the black ano!

No jk. It's mostly the alloy. 7075 has over twice the tensile strength of 6005. (Based off of strengths I found here http://alcobrametals.com/guides/aluminum) I think the cross-section of the thunderhex is also stronger but that probably has a smaller impact than the alloy.

(And Allen beat me to it...)

[Mr V]

Originally Posted by AdamHeard

We have no issues teaching kids to do either of these... It's standard practice on our team and kids do both all the time.

I guess it must be the students on our team but we don't haven't had that many that are interested in using the lathe let alone becoming competent in using it. We do however typically have one student that quickly decides it is his or her favorite machine and does become quite competent. Of course when you need something right now that student seems to be absent that day.

[tim-tim]

You can always tap for a #10-32 heli-coil, threaded insert. I'm a #10 and #8 guy. If I had to use 1/4", it would be 1/4-28.

Originally Posted by AdamHeard

I'm Mr #10. It's my favorite fastener, and we've used it forever.

That being said, the more COTS teams are in 1/4-20 land. This makes sense.

Being Mr #10, I'm STOKED about the hole as we'd never use a bolt to retain the items on a shaft... but these will make great heavy duty standoffs with the hole already drilled.

ThunderHex is my favorite new product, and I think they did it perfectly. Now time for 3/8" thunderhex next year

[AllenGregoryIV]

Originally Posted by tim-tim

You can always tap for a #10-32 heli-coil, threaded insert. I'm a #10 and #8 guy. If I had to use 1/4", it would be 1/4-28.

Why the fine threads?

[Lil' Lavery]

Originally Posted by Andrew Lawrence

I would say that the original aluminum would be better for drivetrain and other high load applications. These new plastic ones would work well in things like intakes where there isn't a lot of torque trying to break the hub apart.

Personally, I'd be less worried about breaking the hub apart and more worried about gradual wear along the corners of the hubs leading to backlash.