Hello
Time to install the hopper extension for the Harman P-61a. This hopper extension was not purchased thru a Harman Dealer and certainly may not be made by Harman.
There were no holes drilled in the extension and no bolts or screws provided.
My question is:
Should nuts and bolts be used or are self tappers strong enough?
I do like the nuts and bolts because I could tighten them down on the RTV and make a good air tight seal!
Here is what I did.
The original hopper lid has a piano hindge and was riveted into the top of the hopper. It took a 1/8" titanium drill bit to drill out the rivets. I placed paper towel in the bottom or the hopper to catch the rivets as they fell. Falling in pellets is like falling in quick sand! I drilled out the rivets in the hindge and removed the lid. Because of other rivets in in the top, the extension did not sit as flush as I liked. So I drilled out the rest of the rivets and the two back corner reinforcement plates fell out. I also banged down the back corners with a hammer to make them flatter.
At this point I decided to use nuts and bolts. I found that 6-32 bolts would fit into the small holes the rivets came out of. Those bolts are tiny, so I got an 11/64" drill bit and reamed the holes so the heaftier 8/32" bolts would fit. I put the extension on the hopper making sure the latch tab was in front. Then using a felt pen I marked all the existing holes. Any holes I could not find could be measured and marked with the measure tape. I also decided not to use the holes in the two front corners because they would go thru the seam in the extension. So I measured an inch from the corner and made 2 new holes for the front.
Continued
Time to install the hopper extension for the Harman P-61a. This hopper extension was not purchased thru a Harman Dealer and certainly may not be made by Harman.
There were no holes drilled in the extension and no bolts or screws provided.
My question is:
Should nuts and bolts be used or are self tappers strong enough?
I do like the nuts and bolts because I could tighten them down on the RTV and make a good air tight seal!
Here is what I did.
The original hopper lid has a piano hindge and was riveted into the top of the hopper. It took a 1/8" titanium drill bit to drill out the rivets. I placed paper towel in the bottom or the hopper to catch the rivets as they fell. Falling in pellets is like falling in quick sand! I drilled out the rivets in the hindge and removed the lid. Because of other rivets in in the top, the extension did not sit as flush as I liked. So I drilled out the rest of the rivets and the two back corner reinforcement plates fell out. I also banged down the back corners with a hammer to make them flatter.
At this point I decided to use nuts and bolts. I found that 6-32 bolts would fit into the small holes the rivets came out of. Those bolts are tiny, so I got an 11/64" drill bit and reamed the holes so the heaftier 8/32" bolts would fit. I put the extension on the hopper making sure the latch tab was in front. Then using a felt pen I marked all the existing holes. Any holes I could not find could be measured and marked with the measure tape. I also decided not to use the holes in the two front corners because they would go thru the seam in the extension. So I measured an inch from the corner and made 2 new holes for the front.
Continued
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