Superfeet design

B

Boyd Allen

Active member
I have three 1/8" aluminum discs, that are 3 1/2" in diameter, that I am replacing the bottom facings on. (They are to be used under the points of my rifle rest.) What materials have you used, and what glue did you use? Do you think that this is too much area for a 10 1/2# rifle on a Hart rest. If it is, I have considered three equidistant patches of some material, instead of covering the whole bottom. How do you think that that will work?
 
You know,

Dave Dohrman was a hell of a good guy, but has anyone proven beyond a shadow of a doubt that superfeet are really all that super? I used them for a year and my rest seemed to like to wander around on the benchtop as I shot it. When I went back to the Hard .30 cal AP tips, all was better.

Paul
 

Attachments

  • Good Tip.jpg
    Good Tip.jpg
    11.4 KB · Views: 277
  • feet2.jpg
    feet2.jpg
    27.4 KB · Views: 322
Does anyone make those carbide points for sale?

When I built my rest I used 1/2 - 20 for the adjustment bolts, but I would like to drill them and put in points like you have.

Thanks Gary

On the superfeet I would think the main advantage would be that it keeps the bench top from getting all chipped up.
 
What was the goal(s) of the superfeet? Is it solely to keep a concrete bench from getting chewed up? Do some feel there is an isolation issue? I would imagine the best material to use for superfeet would depend on that.

If vibration plays no part, then we have a situation where the competitor wants a rest that won't move. The club wants a bench top that doesn't have to be repaired. The quick solution is to clamp the rest to the top, but the rules prohibit this. Always ways around the rules, and 100-pound rests might be just the ticket to bring more young people to benchrest . . .

If vibration control is a goal, then you need something like rubber for that, and maybe a course sandpaper for contact with the bench top. Rubber alone picks up dirt & dust & quickly becomes slippery. Guess I'd use a good layer of vibration-absorbing material, with an easily replaceable piece of anti-slip material.

Pointed cones have a long history of minimizing the transmission of vibrations. They are used in high-end audio installations. Except for marring the bench tops, the carbide tips are, perhaps, the best solution.

Question is, is isolation from vibration needed?
 
You see people hammering on the bench top to place their rest in place so that it doesn't move. With these Hard tips, there is no need for that, just place the rest on the bench and all the weight is divided on three very small points. No movement no hammering.

I put those tips in my rest legs. They are .30 cal AP penetrators. (Black Tip .30-06 military) You can find them at gunshows now and then.

Paul
 
I'm very happy with my superfeet, as a matter of fact, yesterday I spent about 6 hours with my rail gun. It never moved all day.
 
The only time my superfeet failed to hold was when the shooter I was sharing a bench with spilled a whole bottle of talcum powder all over the concrete bench top . I had to wash the baby powder off the superfeet and the bench top with water before they would take hold again.

Rodney
 
Thanks for the input everyone. As I am sure he did with many of you, Dave and I discussed products and ideas at length, on the phone, dating back to when I used to do product articles for Shooters News. During one of those conversations he mentioned that the first superfeet that he had made had thicker rubber on the bottom, and that testing showed that this had a negative impact at the target. Given this information, my plan is to keep what ever I use as thin as possible. One thought was double faced tape, and just replacing it as needed. Opinions?
 
My rest feet are made from a hard plastic furniture pad with a cast-in steel washer and self adjesive furniture pads about the same od as the hard pad. Simple and cheap. Easy to lose.

The rest doesn't move on a concrete bench top. I'm not sure either one of the guns I shoot off them are accurate enough to discriminate whether they hurt or help.
 
Boyd,

I come back to the question of what problem(s) are superfeet designed to solve. Movement of the rest alone? Then the tape is worth a try. Vibration control? Then no. If thick rubber had a negative impact, It does sound as if dampening (vibration control) is not much of an issue -- unless the thick rubber tried was also flexible enough to cause movement issues.
 
Charles,
They protect the bench, bridge over the gaps (allowing more latitude of placement on a damaged bench), keep one from unknowingly having a unlimited base leveling point fall into a hole while running a group, and locate a rail or rest on the bench with precision. An example of the last item can be seen in these two pictures. A while back Gary Ocock shot a potential record 5-5 unlimited agg, at Visalia. I guess I should ask Gary what is on the bottom of his disks, since they seem to work so well.
Boyd

Visalia10-18-09fiveshotunlim015.jpg

Visalia10-18-09fiveshotunlim017.jpg
 
Boyd ...

Boyd Allen said:
I have three 1/8" aluminum discs, that are 3 1/2" in diameter, that I am replacing the bottom facings on. (They are to be used under the points of my rifle rest.) What materials have you used, and what glue did you use? Do you think that this is too much area for a 10 1/2# rifle on a Hart rest. If it is, I have considered three equidistant patches of some material, instead of covering the whole bottom. How do you think that that will work?
Click to expand...

Give John Loh a call at 562-602-5553. He's got a new product for use under his front rest legs that makes it extremely stationary. I've got both [rest and base] and could never be more pleased. Little known fact, John has over 100 products in his benchrest lineup that I wish he would take pictures of and then post at his internet site. :)
 
If you look in either MSC or McMaster Carr, they have sheet neoprene with an adhesive backing. It comes in various thicknesses and different elasticity. Get the softest most flexible to get the "grip" on the bench. Making the "feet" is not a big issue.
 
I have been using some that I made out of a few die slugs #10 gauge steel 3.125 OD that i used just ordinary contact cement and some leftover rubber roofing that is approx. .062 thick. I just spread the contact cement on each and let set a few minutes then repeated that again and put them together, then set 10# weight on top of them and let them dry then painted them. They have lasted for two seasons now and same for the sets I made for friends and theirs are still ok.
Denton Smith
 
Last edited by a moderator:
Feet

A friend loaned me his Bald Eagle rest and suggested I needed to make super feet and ground feet to use with it. I bought aluminum scrap at the salvage yard for $1/lb. and 1-1/2" self-stick grippers (furniture pads) at the hardware store. I recessed the bottom of the aluminum disks to accept the textured rubber pads and used a 90 deg countersink for the rest feet. I've used them on our ranges concrete benches and can't see that they move. The bench tops are pocked up from rest feet and the pads aren't affected by that. - nhk
 

Attachments

  • Bench rest feet.jpg
    Bench rest feet.jpg
    26.3 KB · Views: 275
I finally got to the range, and tested one answer to what to put on the bottom of the 1/8" x 3 1/2" aluminum disks.

To review, my wife had picked up some give-aways at a safety fair at her work, including a .040 thick x approx. 6" dia, jar opener. It is made of recycled tires, and was designed as a grip aid.

Previously I had considered that if I covered the entire bottom of the disks, that the unit loading might be too small, for whatever material I chose to get a grip on a bench top. To get around this, I decided to try three quarter sized pads, evenly spaced, around the edge of each disk. The adhesive was superglue.

Bottom line, they seemed to work very well, although I have to admit that since it had been a long time since my last range visit, that I was not as sharp on a few of the small details as I might have been. Nevertheless, I had a good time, and learned a thing or two. In the last hour, before it got too dark to shoot, it got amazingly still. I think that I need to plan my next trip so as to be able to take maximum advantage of this phenomenon. The surveyor's tape didn't even twitch for long periods of time.
 
Go to Wally world, electronics section, and pickup the cheapest mouse pad they have. Glue to bottom of disks with contact cement, after dry trim to size. Works great. Cost less then $2.00 the last that I bought.
Jerry
 
Boyd, If you want an adhesives backed product as Wayne says www.Mcmaster.com has what you need.
They have with and without adhesive back material. If you get the non-adhesive backed material you will have to buff the side the glue goes on. Comes in 12" x 12" sheets, 1/16" (8456k11), 3/32" (8456k22), 1/8" (8456k13) etc., and larger sizes.
You have to pick the Hardness from 30A soft, 40A medium soft, 50A medium, 60A medium hard, 70A hard, 80A harder.
I bought some awhile back and use it under my rear bag.
Centerfire
 
You must log in or register to reply here.
Back
Top