Talk:Paintball gun

From DDL Wiki

We received your report, and we are impressed with your findings. Detailed comments follow:

• Please include a picture of the product
• Executive summary okay, but more conclusions up front would be helpful in understanding your findings
• Nice overview of user needs
• Very clear verbal description of functionality, and the figure helps with geometry; however, a picture of the gun with the housing removed would make the descriptions much easier to understand physically.
• Very clear explanation of trigger.
• Great component list. Do you think that reaming is required for the barrel? Is the QTY correct for all parts? (o-rings, for example)
• Great DFMA observations - looks like the design is in good shape.
• Good observations for FMEA - we will consider pursuing an analysis of a factor of safety to plastic deformation on the spring catch, as you recommend
• The LCA is interesting. We noticed that you did not consider the use phase. Does the gun manufacturing impact dominate impact from use of paintballs and compressed gas?
• The suggestions for returning the product at end of life is interesting - aluminum has enough value for recycling that it may be worth our while to pursue design of recycling collection logistics.
• Your improvement opportunities are interesting - we look forward to seeing your next report
• Does the current product work well for left-handed users or dominant left-eye users?
• Your analysis predicts a range of 41m at 5.5 ft off the ground before the paintball hits the ground. This ballistic analysis is interesting, although users could simply aim the gun slightly up to increase this range. But for measuring effective range for a game, it seems also important to know how far the paintball will travel before the velocity is too slow to break the paintball shell on contact. Do you have a feeling for this range? How do your calculations compare to reported ranges for this and/or other paintball markers? Is this a good range? What can you conclude from your analysis.

Response

Elaborated on Excutive Summary.

• Please include a picture of the product.

Photo added to page.

• Very clear verbal description of functionality, and the figure helps with geometry; however, a picture of the gun with the housing removed would make the descriptions much easier to understand physically.

Unfortunately the main housing of the gun is one peice, so an internal view of the housing can not be seen. However, all parts used in the description can be seen in the components list. Also, a video of the gun being cocked and the trigger being pulled can be seen here[1]. In this video, you can see the venturi bolt moving out of the way of the feed hole to allow a paintball to drop in. When the trigger is pulled, the venturi bolt is released. It first strikes the paintball then accelerates it out of the barrel using a burst of compressed air.

• Great component list. Do you think that reaming is required for the barrel? Is the QTY correct for all parts? (o-rings, for example)

Yes, the barrel probably needs to be reamed as part of the finishing after being cast. QTY of parts (specifically o-rings) has been adjusted.

• Your analysis predicts a range of 41m at 5.5 ft off the ground before the paintball hits the ground. This ballistic analysis is interesting, although users could simply aim the gun slightly up to increase this range. But for measuring effective range for a game, it seems also important to know how far the paintball will travel before the velocity is too slow to break the paintball shell on contact. Do you have a feeling for this range? How do your calculations compare to reported ranges for this and/or other paintball markers? Is this a good range? What can you conclude from your analysis.

The velocity of the paintball gun after 0.58s has not slowed down enough to affect the paintball breaking on contact. The range and velocity of this paintball gun is on par with other lowend commercial paintball guns (average range for other paintball guns ~130ft). From this analysis you can see that because of the muzzle velocity restriction, most paintball guns have similar ranges. An opportunity for improvement to give the user an edge over the competition would be to increase the range of the paintball gun.

• The LCA is interesting. We noticed that you did not consider the use phase. Does the gun manufacturing impact dominate impact from use of paintballs and compressed gas?

Use phase added to Design For Environment heading, under subheading CO₂ Emissions During Use. We decided this was more of a concern than environmental contamination from paintballs.

• Does the current product work well for left-handed users or dominant left-eye users?

The gun's hopper feed neck and hopper are currently angled off to the right side of the gun. This would pose a problem for a player trying to use their left eye to aim down the barrel of the gun. Alternatives to the current hopper position could be an opportunity for improvement.