It depends on the size of the heli and how you’re mounting it.
Vehicle mounting: Generally four clamps per heli, though with 500 size and smaller, you can get by with two clamps—one on each skid placed at opposite corners.
Trailer mounting: Definitely four clamps per heli. And if you want to be really safe, mount a 1x2 block with some cushioning material (rubber weather stripping works well) under the rear end of the skids for extra support and to absorb some of the up and down shock trailers are known for. This is especially important for models with CF skids like the SAB Goblins.
Wall mounting (static display, hanging tail down): Two clamps, one on each skid, placed just behind the forward skid strut is fine for 500 size and smaller helis. But for helis larger than 500 size we recommend using four clamps per heli and placing them so that each Clamp is just below the skid strut. The idea is for both the upper and lower Clamps to carry some of the weight. Also definitely check the fit of the Clamps when wall mounting helis 600 size and up. If the Clamps are tight and the heli will be wall mounted for extended periods, the stress on the Clamp could lead to failure. Recommended practice is to remove some or all of the 1mm high rib between the 'grippers' in the Clamp base so they'll be easier to open and close and to relieve the stress on the Clamps.
Wall or ceiling mounting (static display, angled): Generally four Clamps per heli on any model larger than a 500 size.
Why are skid clamps packed as a pair when I need four to mount a heli?
At a minimum you need two Skid Clamps for securing a helicopter. While we recommend four Clamps for transporting anything larger than a 500 size heli, it's up to you. Some people want to save money and find two Clamps sufficient. So it makes sense for the standard kit be two Clamps plus hardware. The only cost savings in a 4 pack would be the plastic bag and bag label—just pennies. It wouldn't be worth the extra complexity in keeping 2-packs and 4-packs in inventory.
Can I use other hollow wall/drywall anchors instead of the ones Random RC sells?
Sure. You may even be able to buy the same
Snap-Skru ‘Toggler’ anchors we sell. But there are two benefits to buying the ones we sell. 1) Convenience—if you don’t already have them in hand, it saves a trip to the store. 2) The screws we include in our kits have truss heads. The diameter of the truss head is larger than standard heads so it the spreads the holding force over a larger area and does a better job of anchoring your Skid Clamp to the mounting surface.
Where can I get the parts for that sliding track set up I saw you demo?
A ton of guys kept asking us to sell the track system. So we invested in the tooling and we're extruding the T-Track in rigid PVC (like they use to make schedule 40 pipe) right here in the USA! We've got the thumbscrews and track nuts to go with them. The T-Track and hardware are compatible with ALL Skid Clamp models. Links to the product pages are below.
Is my Skid Clamp defective? What's the warranty policy?
All of our Skid Clamp models are quite strong and very durable. Despite that, we do hear from a few pilots who have had a problem. Don’t worry, we’ll fix you up. Just send an email to
email@example.com, tell us what happened and include a picture of the broken part. We’ll replace the broken parts at no charge and give you some tips about how to avoid breakage in the future. Bottom line, we want you to be totally happy with your Skid Clamps.
My Skid Clamps are too tight. What's wrong?
First, check to see that you've got the right Skid Clamps for your particular skids. There are two ways to do this. First, have a look at the
"What size Fits My Heli page." Second, you can measure your skids and see if the diameter (or Nominal Height, in the case of Goblin-style CF skids) is near the dimensions shown on the Tech Specs page. If your skids are a close match for the nominal dimensions, but the Clamps just feel too tight, here's a trick. Back off the mounting screws 1/4 turn. See if that helps. Loosening the mounting screws a small amount lets the Clamp base flex and makes opening and closing much easier. Conversely, if you want to tighten them up a bit, increase the tightness of the mounting screws. The second adjustment you can make it to remove some or all of the 1mm high rib between the grippers in the Clamp base. It'll make a huge difference and make 'too tight' Clamps easier top open and close.
My Skid Clamps seem too loose.
The first thing to check is the mounting screws. Fully tightening the mounting screws will make the Clamp tighter. If the Clamp is still too loose you can add a 'shim' to the underside of the latch (see the video below: "How to Tighten Up Your Random RC Skid Clamps") or to the 'ramp' feature on the base of the Goblin-style Clamps. For the shim material you can use a small piece of adhesive backed gyro tape or the grip discs that are included with Goblin-style Clamps.
The data in our skid size list are based on the skid parts specified in the manufacturer’s manual for each model. The majority of the dimensions were confirmed with physical measurements. Of course there could still be errors and if you believe you found one, please send an email to
firstname.lastname@example.org and let us know. But usually when a pilot has this issue it’s because he’s installed upgraded or after market landing gear and forget that they’re not the ’stock’ skids the model came with. By the way, if you have a heli model that's not shown in our database, we'd love to add it. We'll send you a $10 OFF coupon for sharing the size data and helping us build the best skid size database on the web.
What does *USER MOD in the Skid Size data table mean?
Original Skid Clamp models can be modified to accommodate skid pipes up to 1mm larger than their nominal design diameter. Using a hobby knife, remove all or a portion of the center rib in the clamp base. Have a
look at this drawing and see the note on the left side of the page.
What about Skid Clamps for small helis?
The STC5565 Skid Clamp is designed for a nominal skid pipe diameter of 5.5mm-6.5mm. It is the smallest Clamp we make. But guys have come up with some very clever mods to accommodate much smaller skid diameters using shim and nitro fuel tubing. Have a look at these videos from two Skid Clamp users for ideas. (Thanks Hal. Thanks Mark.)
Why is the cost for shipping outside the U.S. so high?
We use USPS Priority International and the base rates are between $24 and $36 depending on the destination country. That's the amount we pay to ship internationally. To make it a bit less expensive for customers outside the US we actually subsidize the cost of international shipping. Here's the
table of international shipping charges currently in effect. You can see that as your order size increases your shipping cost goes down. If you live outside the US and your planned order is small, we encourage you to check out our list of international dealers to see if you can get what you need closer to home and for less money.
Man, these things seem really expensive for just a couple pieces of plastic!
We invented Skid Clamps to offer RC Heli pilots a simple, convenient, reliable way to secure their models for transport and for storage when they're not flying. Like most pilots, we rigged up velcro, bungees, wing nuts, towel rods, and broken main blades to do the job. But they were cumbersome, unreliable, and a hassle to build and use. So the
value of Skid Clamps is what they do for pilots not just what they are made from.
Secondly, injection molding tools are expensive (think small car expensive). Part of the selling price of each product goes toward recovering the cost of the tools. Because the RC helicopter market is really quite small that cost is actually greater than the cost of the raw material! This is not unusual with molded parts.
Finally, we could sell Skid Clamps for less if we made them in Asia. But making our stuff in the US is a core value of our business and the couple of bucks more we need to charge to create some jobs in America is a tradeoff we think is worth it. We hope you agree.