how do you attach bumper spikes?

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dmitrym

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I feel kinda dumb asking this question but here it goes anyway. I ordered a set of bumper spikes for my poulan pro 4218. They seem to match up fine to the holes. But when I go to screw them into the body there's no thread there.... how is it supposed to work? What am I missing?

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No, the holes/screws do not go all the way thru. 1" length MAX.... Probably get away with using 3/4"...... I have done this 9 times this past summer with no ill effects at all. Factory screws do the same thing. The holes have no threads at all from factory unless someone added a dog at one time.

Just remember, don't crank down on them too tight.... holes just plastic......they will strip.
 
These holes would take self tapping screws made just for plastic
 
If you measure the hole and compare it to the tap drill size for say a 6mm or 1/4-20 bolt, you can run a taper and bottom tap in and use machine screws with lock washers. Works the same as a self tapping screw, but is an additional step in manufacturing, so the manufacturer uses self tapping screws.
 
I feel kinda dumb asking this question but here it goes anyway. I ordered a set of bumper spikes for my poulan pro 4218. They seem to match up fine to the holes. But when I go to screw them into the body there's no thread there.... how is it supposed to work? What am I missing?

View attachment 951117

View attachment 951118
I have put these on 2 poulan saws with the screws mentioned and they
have not loosened or fallen off. Screws cut threads into the plastic.
 
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